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  • 1990 - 1994  (512,869)
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  • 1
    ISSN: 0370-2693
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0370-2693
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
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  • 3
    Electronic Resource
    Amsterdam : Elsevier
    Physics Letters B 341 (1994), S. 109-122 
    ISSN: 0370-2693
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
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  • 4
    Electronic Resource
    Amsterdam : Elsevier
    Physics Letters B 341 (1994), S. 245-256 
    ISSN: 0370-2693
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
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  • 5
    Electronic Resource
    Amsterdam : Elsevier
    Physics Letters B 324 (1994), S. 500-508 
    ISSN: 0370-2693
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
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  • 6
    ISSN: 1435-1803
    Keywords: Echocardiography ; blood volume ; vascular filling state
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary To assess the hypothesis that echocardiographic variables vary as a function of baseline blood volume and change in response to changes in vascular filling state, we evaluated the relationship between the atrial and ventricular dimensions and left ventricular function, as measured by combined Doppler and M-mode echocardiography on the one hand, and blood volume as measured by a standard radioactive isotope technique on the other. Furthermore, we determined the effect of an increment in vascular filling state induced by plasma volume expansion. Test subjects were ten male and six female volunteers. Blood volume/kg was the only factor not different between male and female subjects and therefore suitable for our study. None of the echocardiographic variables correlated with blood volume/kg. Volume loading increased stroke volume, left atrial diameter, right atrial area, left ventricular enddiastolic dimension, mean velocity of circumferential fiber shortening and left ventricular ejection time. It is concluded that echocardiographic variables are unsuitable for estimating blood volume. Serial measurements of atrial dimensions and left ventricular dimensions are useful for detecting rapid changes in vascular filling state.
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  • 7
    ISSN: 1435-1803
    Keywords: Myocardial ischemia ; coronary reperfusion ; stunned myocardium ; postischemic dysfunction ; oxygen consumption
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Despite apparently depressed function, stunned myocardium maintains oxygen consumption and has the capacity to increase contractility with inotropic stimulation. We hypothesized that during stunning, O2 demand is maintained because regional segment work is performed, but is asynchronous with global left ventricular contraction, and that inotropic stimulation would restore regional work and synchrony. Thirteen open-chest anesthetized dogs were subjected to three left anterior descending (LAD) coronary artery occlusions (10 min) and reperfusions (15 min) to produce regional myocardial stunning. Segment shortening and force development were measured independently and simultaneously in the LAD (experimental) region and circumflex (control) regions. Regional myocardial work was calculated as the integrated product of instantaneous force and shortening, during two periods: 1) over the entire cardiac cycle (Positive Work), and 2) limited to the systolic portion of the cardiac cycle (Systolic Work). Regional myocardial O2 consumption (MVO2) was calculated from regional blood flow (radiolabeled microspheres) and O2 saturation data (microspectrophotometry). Occlusion of the LAD produced a delay in onset of segment shortening in the ischemic region, but not in regional force development. A time delay of 67–81 ms persisted through the three stages of occlusions and reperfusion. Systolic regional work was depressed to a greater extent (924±182 to 149±118 g*mm*min−1) than total positive regional work (1437±337 to 857±174 g*mm*min−1). Regional subepicardial MVO2 in the stunned region was not different than in the control region (7.3±1.5 vs. 6.9±1.4 ml O2*min−1*100 g−1). Local infusion of isoproterenol reversed the delay in regional shortening from 73±7 to 21±8 ms, thereby augmenting systolic work (298%) more than positive work (60%), without a significant increase in MVO2 (7.3±1.5 to 10.5±3.2 ml O2*min−1*100 g−1). It is concluded that myocardial stunning decreases regional systolic work due to regional mechanical asynchrony, while MVO2 is used supported total positive work which was not significantly reduced. Isoproterenol restores regional work by restoring synchrony, without greatly affecting regional MVO2.
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  • 8
    ISSN: 1435-1803
    Keywords: 81Rubidium/81mkrypton ; myocardial perfusion ; myocardial perfusion reserve ; isolated rabbit heart ; Langendorff preparation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Purpose The purpose of the study was to verify that the81Rubidium/81mkrypton (81Rb/81mKr) method allows the quantitative measurement of myocardial perfusion. Principle The potassium analogous cation81Rb is accumulated in the myocardium by the cell membrane-bound Na−K-ATPase. After accumulation an intracellular equilibrium establishes between81Rb and its radioactive daughter nuclide81mKr. The flow-sensitive method evaluates the disturbance of this equilibrium by perfusion which washes out the short-lived diffusable daughter nuclide81mKr while the mother nuclide81Rb remains cell-bound. Methods Isolated rabbit hearts were prepared in a modified Langendorff technique which allowed quantitative collection of the coronary sinus efflux. The myocardium was labeled with pure81Rb by bolus injection into the aortic cannula. Spectroscopic measurements of81Rb and81mKr gamma radiation were performed using a germanium detector. Perfusion was varied in the range between 0 and 4 ml/min/g. The activity ratio81Rb/81mKr was determined and compared with coronary sinus effusion. Results 81Rb/81mKr activity ratio was closely related (r=0.98) to perfusion as described by the predicted equation Rb/Kr=(F/2.96 P)+1. (Rb/Kr=activity ratio between81Rb and81mKr in the myocardium; F=myocardial perfusion (ml/min/g); P=partition coefficient (myocardium/perfusate) for Krypton gas.) The constant P was found to be 1.14±0.06 (mean±SEM). No saturation of this ratio at high flow rates was observed. Conclusion The activity ratio81Rb/81mKr is a valid quantitative measure for myocardial perfusion in isolated hearts. The main limitation of the method before application in man is the correction of the different gamma ray tissue absorption of both nuclides.
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  • 9
    ISSN: 1435-1803
    Keywords: Coronary blood flow ; myogenic responses ; coronary transmural pressure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effects of transient changes in coronary transmural pressure on the coronary vasomotor tone was studied in 23 anesthetized dogs. Increases and decreases of the coronary transmural pressure were obtained by constrictions of various duration (2 to 20 s) of the descending thoracic aorta. The maneuvers were performed in animals with intact cardiac innervation, with the vagi sectioned and with vagal section together with β-blockade. In the absence of β-blockade the increase in the transmural pressure caused a transient increase in the coronary vasomotor tone attributable to a myogenic contractile response and the extravascular compression. This contractile response was not observed when the transmural pressure was increased in the presence of high vasomotor tone after β-blockade. In all animals a transient hyperemia was seen with its peak 8 to 12 s after the release of the aortic constriction. Since its timing and amplitude were independent of the duration of the constriction, the metabolic effect of the increased ventricular afterload, although it may have contributed to the decrease of the coronary resistance, cannot be considered entirely responsible for the hyperemia, which was otherwise compatible with a myogenic vasodilatory response triggered by the sudden fall of the transmural pressure at the release of the constriction. It is concluded that, in the coronary circulation of the intact dog, transient changes in transmural pressure can induce vasomotor responses in which myogenic and metabolic mechanisms combine together in regulating the coronary flow. Changes in extravascular compression can also affect the flow when the experimental maneuver implies changes in the diastolic left ventricular pressure and volume. With the present experimental procedure the myogenic responses have been evidenced when the metabolic factors would have been expected to produce opposite changes in the vasomotor tone.
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  • 10
    ISSN: 1435-1803
    Keywords: Magnesium ; metabolism ; fatty acid ; glucose ; reperfusion ; rat heart
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary To determine the effect of magnesium on myocardial function and oxidative metabolism after reperfusion, isolated rat hearts perfused retrogradely with erythrocyte-enriched medium (0.4 mM palmitate bound to 0.4 mM albumin, 11 mM glucose) were subjected to 60 minutes of no-flow ischemia followed by 60 minutes of reperfusion. Untreated postischemic hearts exhibited after 15 minutes of reperfusion recovery of myocardial oxygen consumption to 65% of the preischemic value despite persistent depression of left ventricular isovolumic pressure development to 21%. Magnesium (15 mM) administered during the initial 30 minutes of reperfusion reduced myocardial oxygen consumption of reperfuse myocardium by 35%. Oxidation of [1-14C]palmitate was slightly more reduced (−55%) than oxidation of [U-14C]glucose(−42%). Magnesium did not influence ultimate recovery of contractile function and cumulative myocardial release of creatine kinase. Thus, 15 mM magnesium administered during reperfusion elicited a reduction of oxidative metabolism. However, magnesium did not modify myocardial injury.
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  • 11
    ISSN: 1435-1803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 12
    ISSN: 1435-1803
    Keywords: Colored microspheres ; borderzones ; coronary microcirculation ; coronary occlusion ; extended perfusion boundaries ; regional myocardial differences
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Simultaneous in vivo infusions of two different colored 10 μm microsphere suspensions into the left anterior descending (LAD; red spheres) and left circumflex (LCx; blue spheres) coronary arteries of nine anesthetized dogs identified a specific region of canine myocardium perfused by both arterial branches. Subsequently, the LAD was ligated and a third (green) set of micropheres was infused into the patent LCx artery. Analysis of 40 μm serial sections of tissue revealed interface zones with capillaries perfused by both arteries. The first zone, defined as the Interface Transistion Zone (ITZ) was formed by an intermingling of microvessels supplied by the parent arteries of the adjacent perfusion territories; it separated tissue containing only one or the other colored microspheres. Another zone, defined as the Boundary Watershed Zone was located within the ITZ and had capillaries containing both red and blue microspheres. The width of ITZ was 53377±817 μm (mean±SD), and the width of the BWZ was 3358±618 μm. Green microspheres, infused into the LCx following coronary occlusion were also found in the ITZ and BWZ. Furthermore, capillaries perfused exclusively by the LAD before occlusion (tissue with red but not blue microspheres) adjacent to the perfusion interface contained green microscpheres as well as red/green aggregates, indicating lateral extension of the LCx perfusion territory. This extension of the LCx territory was quantitated by comparing the location at which densities of green microspheres or green/red aggregates decreased abruptly compared to the location of the original ITZ and BWZ boundaries, respectively. Results showed that LAD occlusion caused a 24% expansion of the ITZ and a 48% expansion of the BWZ. In addition, all expansions were significantly greater in subepicardial compared to subendocardial regions (p<0.001). These results clearly demonstrate the capability of microvascular anastomoses in providing blood flow to the periphery of an ischemic region. Furthermore, the perfusion interface is labile and might be amenable to manipulation.
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  • 13
    ISSN: 1435-1803
    Keywords: Collagen ; heart ; histology ; polarized light microscopy ; stains and staining
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Collagen plays a major role in the structural organization of the heart and therefore direct visualization of collagen fibers is a crucial component of cardiac analysis. Although linearly polarized light has proven an effective tool for the examination of myocardial collagen in histologic sections, the use of circularly polarized light may offer advantages and additional possibilities. We examined the potential enhancement of collagen analysis using circularly polarized light in two ways. We first measured the brightness, and hence indirectly assessed the birefringence, of collagen fibers in scars examined at different times after myocardial infarction. Secondly, we measured collagen content in myocardial tissue and compared results obtained from brightfield analysis of trichrome stained sections with those obtained from circularly polarized light analysis of picrosirius red stained sections. We observed a progressive increase in the maximum brightness of collagen fibers in the scar with time, and a time-dependent shift in the relative distribution of collagen fiber brightness from lower to higher levels. We found consistently lower values of collagen content in trichrome stained versus picrosirius red stained tissue, and concluded that trichrome staining underestimated collagen content. The information provided by these studies could not be obtained by brightfield analysis and could be only partially obtained from linearly polarized light analysis. Thus, analysis using circularly polarized light has the ability to enhance histologic assessment of tissue and can provide additional insights into the composition and structure of myocardial collagen.
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  • 14
    ISSN: 1435-1803
    Keywords: Myocardial electrical anisotropy ; cardiac phase-excitation frequency ; epicardial sensor ; myocardial blood volume
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Knowledge of myocardial electrical resistivity is of interest because passive electrical properties govern the electrotonic spread of current through the myocardium and influence the shape and velocity of the excitation wave. In addition, measurements of myocardial resistivity may provide information about tissue structure and components. The aim of the present study was to determine the excitation frequency dependence and the changes during the cardiac cycle of anisotropic myocardial electrical resistivity. Longitudinal and transverse myocardial resistivity were measured using an epicardial sensor in four open-chest dogs with excitation frequencies in the range of 5–60 kHz. Mean longitudinal resistivity gradually decreased from 313±49 Ω·cm at 5 kHz to 212±32 Ω·cm at 60 kHz, transverse resistivity decreased from 487±49 to 378±53 Ω·cm. To analyze the phasic changes, we compared mean resistivity (averaged over the full cardiac cycle) with resistivity during four cardiac phases: pre-ejection, ejection, early diastole and late diastole. Longitudinal resistivity was significantly higher during the ejection phase (+9.6±4.1 Ω·cm) and lower during late diastole (−6.9±2.9 Ω·cm). Transverse resistivity was significantly higher during late diastole (+4.0±2.3 Ω·m). The values during the other cardiac phases were not significantly different from mean resistivity. The phasic changes in longitudinal and transverse resistivity during the cardiac cycle were independent of the excitation frequency. We speculate that these changes are related to geometrical changes, especially to changes in myocardial blood volume.
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  • 15
    ISSN: 1435-1803
    Keywords: Mechanical restitution ; postextrasystolic potentiation ; interval-force relationships ; transfer function modelling ; LVdP/dtmax
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Objectives The purpose of this study was to explore the physiology underlying the beat-to-beat variations of ventricular function during atrial fibrillation (AF). Methods Left ventricular pressure, and its first derivative (LVdP/dtmax, an index of contractility, and aortic blood velocity (and its integral AVI, an ejection index), were recorded using cathetermounted transducers in 15 patients with AF during cardiac catheterisation. Transfer function modelling was used to examine the influence of preceding intervals on LVdP/dtmax, and of LVdP/dtmax on AVI. The technique also allowed simulation of the behaviour of LVdP/dtmax in response to specific manipulations of interval. Results The variations in LVdP/dtmax recorded from the AF patients were shown to be dependent on up to six preceding intervals; a maximum of 91 % of the variation was explicable in this way. The influences of mechanical restitution (MR, the relationship between preceding interval and contractility), postextrasystolic potentiation (PESP, the inverse relationship between pre-preceding interval and contractility) and the decay of that potentiation were all demonstrated. These influences collectively appeared to be powerful determinants of AVI. Simulations of LVdP/dtmax, following single interval perturbations, were entirely consistent with these interval force effects. Conclusions The cardiac interval force relationship in man is an important determinant of the beat-to-beat variations of contractile and ejection function during AF: the beat-to-beat variations in contractile (or inotropic) function are independent of changes in ventricular filling or fibre-length.
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  • 16
    ISSN: 1435-1803
    Keywords: Heart failure ; tachycardia ; myocyte function ; myocyte structure ; rabbits
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Recent studies have shown that chronic pacing induced tachycardia in large animals such as dogs and pigs causes congestive heart failure accompanied by myocyte contractile abnormalities, neurohormonal activation, alterations in sarcolemmal receptor systems, and changes in myocardial structure. However, fundamental studies directed at identifying basic contributory mechanisms responsible for the development of this form of heart failure are problematic in these large animals. Accordingly, the present study examined the direct effects of pacing induced tachycardia upon LV and myocyte structure and function in the adult rabbit. Twelve adult rabbits (New Zealand White; 3.5–4.5 Kg) underwent 30 days of pacing induced ventricular tachycardia (VT; right ventricular paced, 400 bpm) and 12 additional age and weight matched rabbits served as controls. Echocardiography revealed increased LV end-diastolic dimension (1.92±0.04 vs 1.10±0.20 cm;p<0.05) and decreased fractional shortening (41.5±3 vas 22.3±4%;p<0.05) in the VT group compared to controls with no change in LV mass. Steadystate isolated myocyte contractile function was significantly reduced in the VT group compared to control. For example, isolated myocyte velocity of shortening was 41±2 μm/s in the VT group compared to 84±5 μm/s for controls (p<0.05). In the presence of 8 mM extracellular Ca2+, myocyte velocity of shortening was 40% lower in the VT group compared to controls. Finally, myocyte contractile responsiveness with β-adrenergic receptor stimulation was reduced by 52% in the VT group compared to controls. Isolated myocyte length significantly increased in the VT group compared to control (157±3 vs 128±2 μm;p<0.05) with a concomitant decrease in cross-sectional area (274±6 vs 400±31 μm2;p<0.05). Myocyte myofibril volume fell by 27% in the VT group compared to control with no change in mitochondrial percent volume. In summary, this study demonstrated that chronic pacing induced tachycardia in rabbits caused: 1) LV dilation and dysfunction, 2) depressed isolated myocyte contractile function and inotropic responsiveness, and 3) alterations in myocyte structure and composition. The changes in LV and myocyte function and structure following chronic tachycardia in rabbits are similar to that reported previously with tachycardia induced heart failure in larger animals. These findings suggest that this rabbit model of chronic tachycardia may provide a useful and practical means by which to examine basic mechanisms responsible for the development of congestive heart failure.
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  • 17
    ISSN: 1435-1803
    Keywords: Cardiac ; glycolysis ; heart ; myocardial ; metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The purpose of this investigation was to assess the effects of ischemia and reperfusion on the transmural levels of glucose and lactate in the interstitium in 11 open-chest swine. Microdialysis probes were used to estimate changes in interstitial metabolities across the ventricular wall. Probes were placed in the subepicardium and the subendocardium of the left anterior descending (LAD) coronary artery perfusion bed and in the midmyocardium of the circumflex (CFX) perfusion bed. The LAD coronary artery was cannulated and perfused with blood from the femoral artery through an extracorporal perfusion circuit. Ischemia was induced in the LAD perfusion bed by reducing the flow of the LAD perfusion pump by 60% for 50 min, and was followed by 30 min of reperfusion. Regional myocardial blood flow was assessed with fluorescent microspheres. Ischemia resulted in a transmural gradient in blood flow, with the most severe reduction in flow occurring in the subendocardium (p<0.05). We found a significant reduction in interstitial glucose in both the LAD subepicardium (1.26±0.24 mM) (p=0.0009) and subendocardium (0.89±0.21 mM) (p=0.0001) during ischemia compared to the aerobic (non-ischemic) period (1.97±0.25 mM, 2.03±0.29 mM for the subepicardium and subendocardium, respectively). This coincided with a significant reduction in glucose delivery (LAD pump flow* arterial glucose) to the LAD perfusion bed during ischemia (54.5±8.5 μmol/min) compared to aerobic values (182.1±25.3 μmol/min) (p<0.05). Interstitial lactate levels were significantly increased during ischemia in the LAD subendocardium (3.39±0.46 mM) compared to the aerobic values (1.73±0.46 mM) (p<0.0029). A transmural gradient in interstitial lactate levels was observed during ischemia: this gradient was not seen during the aerobic period and was negated upon reperfusion. In conclusion, ischemia resulted in a decrease in interstitial glucose in both the LAD subepicardium and subendocardium, and an increase in interstitial lactate in the LAD subendocardium. Further, a transmural gradient in interstitial lactate levels was observed during ischemia, with the highest lactate values appearing in the subendocardium.
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  • 18
    ISSN: 1435-1803
    Keywords: Bradykinin ; substance P ; histamine ; angiotensin I-converting enzyme ; neutral endopeptidase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The purpose of this study was to determine the effects of bradykinin (BK), substance P (SP) and histamine on plasma exudation in the skin of conscious dogs with and without pacing-induced heart failure. We also determined the role tissue angiotensin I-converting enzyme (ACE) and neutral endopeptidase (NEP) play in modulating these responses. We found that intradermal injection of BK, SP and histamine induced a significant, concentration-dependent Evans blue exudation in normal dogs (p<0.05). Bradykinin-induced responses were significantly potentiated by captopril (p<0.05). In contrast, phosphoramidon potentiated BK-induced responses only at low concentrations of BK. Both captopril and phosphoramidon had no significant effects on SP-and histamine-induced Evans blue exudation. BK- and SP-induced responses were significantly attenuated, whereas histamine-induced Evans blue exudation was significantly potentiated in dogs with heart failure. We conclude that heart failure is associated with attenuation of BK- and SP-, but not histamine-induced plasma exudation in the peripheral microcirculation and that these responses are not modulated by tissue ACE and NEP.
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  • 19
    ISSN: 1435-1803
    Keywords: Nitric oxide ; Polymorphonuclear neutrophils ; myocardial ischaemia ; reperfusion ; endothelial dysfunction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Nitric oxide (NO) exerts an inhibitory effect on polymorphonuclear neutrophil (PMN) function, via a cyclic GMP-mediated mechanism, while PMNs are known to play an important role in myocardial ischaemia-reperfusion injury (MI-R). Since the major source of NO, vascular endothelium, becomes functionally impaired during MI-R, it is attractive to hypothesize that it is this loss of endothelial nitric oxide production that allows PMN adherence and activation. The studies reviewed here add substance to this hypothesis. Authentic NO, administered during MI-R both reduces myocardial necrosis and PMN accumulation, while basal NO release, as estimated by coronary artery ring responses to L-NAME, an NO synthase inhibitor, declines during reperfusion with a time-course mirrored by PMN adherence in the same preparation. Reduction in infarct size and decreased PMN accumulation can also be demonstrated with L-arginine and NO donors. Since endothelial dysfunction leads to PMN adherence and PMNs have been shown to contribute to endothelial dysfunction, it seems probable that a positive feedback loop is generated during MI-R, leading to the amplification of PMN activity and subsequent myocardial damage.
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  • 20
    ISSN: 1435-1803
    Keywords: Anoxia ; cyanide ; exocytosis ; nonexocytotic release ; neuropeptide Y
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Nicotine-induced noradrenaline was investigated in perfused guinea pig hearts subjected to metabolic blockade that was caused either by anoxia or by cyanide intoxication. Noradrenaline, neuropeptide Y, and dihydroxyphenylethyleneglycol (DOPEG) were determined in the coronary venous overflow. Neuropeptide Y is a sympathetic cotransmitter of nordrenaline, and concomitant release of both transmitters indicates an exocytotic, calcium-dependent release mechanism, whereas neuropeptide Y overflow does not occur during nonexocytotic noradrenaline release. Nonexocytotic, calcium-independent noradrenaline release, however, is associated with an increase of DOPEG overflow, which is the main intraneuronal metabolite of noradrenaline formed by monoamine oxidase if oxygen is present. Anoxia per se caused a nonexocytotic release of noradrenaline starting after 10 min of anoxia and reaching peak levels at 30 min. During anoxia, nicotine (3 and 10 μmol/l) accelerated and enhanced noradrenaline overflow, i.e., the period between the onset of anoxia and the begin of noradrenaline release was shortened and peak levels were increased. Nicotine-induced noradrenaline release was accompanied by neuropeptide Y overflow. The action of nicotine was further evaluated during energy depletion caused by cyanide. As anoxia did, cyanide administration alone resulted in noradrenaline release. In accordance with a nonexocytotic mechanism and due to the presence of oxygen, this release of noradrenaline was accompanied by an increase of DOPEG. When added 10 min after the onset of energy depletion, nicotine (10 μmol/l) caused a brief but marked enhancement of exocytotic noradrenaline release, since this release was calcium-dependent and was accompanied by a significnat rise of neuropeptide Y overflow. In absence of extracellular calcium to avoid exocytosis, concomitant administration of nicotine (3–100 μmol/l) and cyanide caused a concentration- dependent acceleration of both the overflow of noradrenaline and DOPEG, whereas overflow of neuropeptide Y was not increased, thus indicating a nonexocytotic release mechanism. In conclusion, the application of nicotine during myocardial energy depletion increases overflow of noradrenaline by both calcium-dependent exocytotic release and calcium-independent nonexocytotic release mechanisms.
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  • 21
    ISSN: 1435-1803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 22
    ISSN: 1435-1803
    Keywords: isolated rat heart ; graded hypoxia ; heart function ; oxygen uptake ; glycolytic ATP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The aim of this study is to assess whether oxygen supply is sufficient to induce normoxic conditions in isolated rat hearts. Hearts are perfused with a Krebs medium supplemented with 11mM glucose, 0.6 mM lactate, 0.06 mM pyruvate, non delipidated albumin (0.1 mM fatty acids), and either 1.78 mM or 0.76 mM free calcium, at 10ml.min−1. Graded hypoxia is induced by a stepwise decrease of partial pressure of oxygen (PO2) from 660 to 52 mmHg. Contractile performance, oxygen uptake and lactate plus pyruvate balance are assessed. With high calcium, left ventricular developed pressure, dP/dt max and oxygen uptake increase linearly with PO2 up to 660 mmHg; heart rate increases with PO2 up to 250 mmHg and then tends to stabilize. With low calcium, all parameters reach a plateau over 400 mmHg. Lactate plus pyruvate production suggests a stimulation of glycolysis with high calcium, even at 660 mmHg; conversely, there is no lactate plus pyruvate production with low calcium over 250 mmHg. In conclusion, our results demonstrate that, under a high level of calcium at a constant flow of 10 ml.min−1, cardiac function is always limited by O2 supply, except for heart rate. This raises the question as to the definition of a normoxic state. The better preservation of heart rate during hypoxia, compared to other dynamic parameters, could be explained by a contribution of glycolytic ATP.
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  • 23
    ISSN: 1435-1803
    Keywords: SHR ; stress ; noise stress ; ethanol ; hypertensive heart disease ; histomorphometry ; automated image analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The pathogenesis and progression of hypertensive heart disease are unclear; however, both involve a genetic predisposition and environmental influences. To test the role of exogenous factors, we examined the hearts of spontaneously hypertensive rats (SHR) exposed to noise stress and ethanol intake. Twenty-two SHR and nine normotensive Wistar rats (NWR) were continuously exposed to a 65 db, 4 and 250 Hz tone for 52 weeks. Twelve of these SHR aged 20–22 weeks were concomitantly given 20% ethanol in their drinking water up to week 52. Eight SHR and 12 NWR served as controls. We examined hemodynamic parameters, the cardiac configuration, the cardiac microvasculature, interstitial tissue, and ischemic myocardial lesions. We found that noise stress significantly increased the microvessel wall area, the number of microvessels with an outer diameter >19 μm, the degree of cardiac fibrosis, and the extent of ischemic myocardial lesions in SHR, but not in NWR. These effects were all ameliorated and the diastolic blood pressure was lowered by the ingestion of ethanol. Cardiac weights and dimensions, heart rate and dp/dtmax were not influenced by either noise or ethanol intake. These results suggest that hypertensive heart disease in SHR can be aggravated by noise stress. Ethanol ameliorates these changes by mechanisms which remain to be explored.
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  • 24
    ISSN: 1435-1803
    Keywords: Stunning ; Ca++ sensitivity ; isolated heart ; rabbit ; oxygen consumption ; inotropic reserve
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A possible cause for the decreased function in postischemic reperfused (=stunned) myocardium could be a decrease in Ca++ sensitivity. To test this hypothesis, we used an agent with reportedly Ca++ sensitizing properties (EMD 57033) and performed experiments on a total of 17 isolated rabbit hearts that were perfused with an erythrocyte-containing medium in a modified Langendorff setting (hct=30%; Ca++=2.0 meq/l). The hearts were divided into two groups. In one group (n=9), the Ca++ sensitizer (30 μM) was administered to nonischemic myocardium, and in a second group (n=8), the Ca++ sensitizer was administered after 30 min of reperfusion that followed a period of 20 min normothermic, no-flow ischemia. In the nonischemic group, addition of the agent, improved left ventricular (LV) function significantly. In the ischemic group, LV-function was depressed at 30 min reperfusion compared to control. Again, the agent improved LV-function significantly. The increase in systolic and diastolic function was comparable in both groups as well as the oxygen consumption that was significantly increased after administration of the agent. In both groups, the agent neither exhibited significant, positive chronotropic nor arrhythmogenic effects. We summarize that the novel Ca++ sensitizer acts as a potent positive inotropic agent in the isolated blood-perfused rabbit heart. Because of the agent's properties to ameliorate postischemic contractile dysfunction, this general strategy may be useful for treating poorly functioning reperfused myocardium.
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  • 25
    ISSN: 1435-1803
    Keywords: Preconditioning ; stunning ; infarct size ; ATP-sensitive potassium channels ; glibenclamide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Single or multiple brief periods of ischemia (preconditioning, PC) have been shown to protect the myocardium from infarction during a subsequent more prolonged ischemic insult. To test the hypothesis that opening of ATP-sensitive potassium channels (KATP) is involved in this mechanism, either bimakalim, a KATP channel opener, or glibenclamide, a KATP channel blocker, were administered to mimic or to block preconditioning protection in barbital-anesthetized pigs. PC was elicited by a single period of 10 min left anterior descending coronary artery (LADCA) occlusion followed by 15 min of reperfusion before the LADCA was reoccluded for 60 min. Instead of PC, bimakalim infusion was started 15 min before the 60 min LADCA occlusion (TCO) and stopped with the onset of ischemia. Glibenclamide was administered either for 10 min prior to the PC protocol, before bimakakim infusion, or before TCO. Regional wall function was quantified with ultrasonic crystals aligned to measure wall thickening (%ΔWT). At the end of the protocol, infarct size was determined by incubating myocardium with p-nitrobluetetrazolium. In seven preconditioned pigs, infarct size was 9.9±5.1% of the risk region compared with 65.9±6.0% in the seven control pigs subjected to 60 min of ischemia only (p<0.001). In seven pigs treated with bimakalim, infarct size was reduced to 35.3±6.6 (p<0.05 vs. controls). Blocking ATP-sensitive potassium channels with glibenclamide prior to PC abolished its protective effect (infarct size, 62.2±4.5%;p<0.001 vs. PC alone). Glibenclamide also antagonized the protective effect of bimakalim (infarct size, 55.2±4.0%), but did not affect infarct size, when solely administered prior to the prolonged ischemic period (62.2±4.3%). We conclude that in swine myocardium KATP channels are involved in the protective effect of ischemic preconditioning, since glibenclamide completely abolished the protective effect of preconditioning, while bimakalim could — at least in part — mimic it.
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  • 26
    ISSN: 1435-2451
    Keywords: Wound drainage ; Wound secretion ; Wound infection ; Vacuum suction ; Postoperative care
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Vier Niedrigvakuumsysteme (maximaler Unterdruck 380 mbar) und 8 Hochvakuumflaschen (ca. 900 mbar Unterdruck) wurden hinsichtlich ihrer Unterdruck-Volumen-Relation untersucht. Das Volumen, welches noch einen Wundsekrettransport ermöglicht, wurde für jeden Typ bestimmt. Die Verwendung einer Wundsekretimitation als Volumenmedium ergab tendenziell ein geringeres Sogverm6gen als bei der Wasseraspiration. Die Sogleistung verschiedener Drainageschlauchdurchmesser wurde bestimmt. Herkömmliche Drainageschläuche wurden mil der “Ulmer Drainage” und weichen Silikonschläuchen verglichen. Die Ulmer Drainage erreichte eine größere Sogkapazität im distalen Schlauchbereich, was auf die stele Größenzunahme der Perforationen im distalen Bereich zurückzuführen ist. Herkömmliche und Silikondrainagen zeigten ein Sogvermögen, das auf die flaschennahen Perforationen beschränkt blieb.
    Notes: Abstract Four low-vacuum systems and eight high-vacuum systems were examined with special reference to the pressure-volume relations. The maximum filling volume for adequate transport of wound secretion was determined for each type. The use of a synthetic wound fluid instead of water resulted in a smaller aspiration volume. Enlargement of the tube diameter resulted in a reduced initial vacuum for the low-vacuum systems, whereas the high-vacuum systems were not affected. Normal drain tubes were compared with “Ulm drains” and silicon tubes for suction capacity. The suction maximum of normal tubes and silicon tubes was located at the proximal holes of the perforated tubes. The “Ulm drain,” with perforation diameter increasing continuously to the distal end of the tube, was found to exert suction even at the more distal part of the tube. It is estimated that this tube allows locally more balanced vacuum in the wound.
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  • 27
    ISSN: 1435-2451
    Keywords: Aortic aneurysms ; PTFE protheses ; Dacron graft dilatation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Aufgrund der postoperativen Dilatationsneigung von Dacronprothesen und ihren Folgen wie Aneurysmabildung oder Rupturen, die bis zum Prothesenwechsel führten, werden an der Chirurgischen Universitätsklinik Lübeck zwischen Januar und Dezember 1992 bei 15 Patienten als Alternative PTFE-Prothesen eingesetzt. In einem Nachuntersuchungszeitraum von 2 bis 12 Monaten betrug die sonographisch gemessene Dilatation bei Rohrprothesen durchschnittlich 11,6%, bei Y Prothesen im Bereich oberhalb der Bifurkation 11,5 % und in den Prothesenschenkeln 14,6% verglichen mit den in der Literatur beschriebenen wesentlich höheren Dilatationsraten von Dacronprothesen. Es konnten bisher weder die Ausbildung von Nahtaneurysmata, Prothesenverschlüssen noch weitere periphere Verschlüsse oder Perigraftreaktionen beobachtet werden. Die PTFE-Prothese kann nach unseren bisherigen Erfahrungen und den Ergebnissen der Literatur als sinnvolle Alternative zu Dacronprothesen bezeichnet werden.
    Notes: Abstract Postoperative dilatation of Dacron vascular grafts can lead to aneurysms and rupture of the prosthesis making it necessary to change the graft by operation. Therefore, 15 patients at Lubeck University Hospital underwent replacement of the aorta with PTFE prostheses due to infrarenal aortic aneurysms. Ultrasound measurements 2–12 months postoperatively revealed a dilatation of 11.6% concerning tubular grafts, 11.5% for the shafts and 14.6% for the limbs of bifurcation grafts compared to the higher dilatation rate of Dacron prostheses described in the literature. There was no evidence of anastomotic false aneurysms, thrombosis of the limbs of bifurcation grafts, peripheral embolization or perigraft reaction. In conclusion, PTFE prostheses seem to be a means of preventing patients from having secondary complications as a result of graft dilatation. Based on our early results and the results described in the literature, PTFE prostheses can be regarded as an alternative to dacron prostheses.
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  • 28
    ISSN: 1435-2451
    Keywords: Hepatic artery aneurysm ; Minimally invasive surgery ; Complications of cholecystectomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Im Rahmen der Verbreitung der laparoskopischen Cholezystektomie werden zunehmend postoperative Komplikationen beobachtet. Es wird erstmalig ein Aneurysma spurium der A. hepatic dextra nach laparoskopischer Cholezystektomie bei einer 55jährigen Patientin sowie dessen Therapie beschrieben. Im Rahmen des radiologischen Embolisationsversuches trat eine Aneurysmaruptur auf, so daß eine Notlaparotomie mit Ligatur der A. hepatica dextra erforderlich wurde. Der postoperative Verlauf über 6 Monate gestaltete sich komplikationslos.
    Notes: Abstract With the spread of laparoscopic cholecystectomy more and more complications are being reported. For the first time in this paper a pseudoaneurysm of the right hepatic artery as a complication of laparoscopic cholecystectomy in a 55 year old patient is described. During embolization the aneurysm ruptured and an emergency laparotomy was performed. The right hepatic artery was ligated. The postoperative course up to follow-up at 6 months was uncomplicated.
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  • 29
    ISSN: 1435-2451
    Keywords: Non-small-cell bronchogenic carcinoma ; Surgery ; Long-term results ; Tumour recurrence ; Follow-up programmes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Von 190 Patienten mit einem nichtkleinzelligen Bronchialkarzinom, die in der Zeit vom 1. 1. 1977 bis zum 31. 12. 1987 unter kurativer Zielsetzung in der Chirurgischen Universitätsklinik Köln operiert wurden, nahmen 67 (35%) regelmäßig, 64 (34%) unregelmäßig und 69 (31%) nicht an schematisierten Nachsorgeuntersuchungen teil. Bei 33 Patienten (25%) mit schematisierter Nachsorge wurden Tumorrezidive des Bronchialkarzinoms diagnostiziert, von denen 13 (39%) noch asymptomatisch waren. Drei Rezidive (9%) wurden erneut operativ, 7 (21%) strahlen-, 3 (9%) chemotherapeutisch und 20 (61%) ausschließlich symptomatisch behandelt. Die Prognose nach Diagnose des Rezidivs wurde weder durch das Vorliegen von Symptomen noch die Art der durchgeführten Behandlung beeinflußt. Die ermittelten Ergebnisse geben keinen Hinweis darauf, daß die Langzeitergebnisse durch die schematisierten Nachsorgeuntersuchungen verbessert werden können. Angesichts der relativ hohen Rate an behandlungsbedürftigen benignen pulmonalen Erkrankungen (15% der Patienten) und der großen Bedeutung, die die regelmäßige Tumornachsorge für die meisten Patienten (82%) hat, sollte nicht auf eine postoperative Nachsorge verzichtet werden. Außerhalb von klinischen Studien erscheint eine individuelle and symptomorientierte Nachsorge mit gelegentlichen Thoraxröntgenaufnahmen ausreichend.
    Notes: Abstract The outcomes of 190 patients in whom a non-small-cell bronchogenic carcinoma had been resected with curative intent in the Department of Surgery, University of Cologne, between 1. 1. 1977 and 31. 12. 1987 were analysed retrospectively. Sixty-seven (35%) of these patients underwent regular, 64 (34%) irregular, and 59 (31%) no standardized follow-up programmes. During follow-up procedures tumour recurrences were detected in 33 patients (25%). Thirteen (39%) of these recurrences were completely asymptomatic at the time of diagnosis. Three recurrences (9%) were resected with curative intent, but the patients died between 14 and 17 months later due to recurrent disease. Seven recurrences (21%) were treated by radiotherapy, three (9%) by chemotherapy, and 20 patients (61%) received no oncologic therapy. The survival rates after diagnosis of recurrence were not affected by the type of treatment or by the presence of clinical symptoms. There is no evidence that long-term results following resection of non-small-cell bronchogenic carcinoma can be improved by regular and standardized follow-up programmes. The observed incidence of postoperative pulmonary disorders and the patients' self-assessment underline the necessity for postoperative care after resection of bronchogenic carcinoma. Apart from clinical studies, follow-up should primarily focus on individual symptoms and should no longer include standardized investigations in asymptomatic patients except occasional X-ray checks of the thorax.
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  • 30
    ISSN: 1435-2451
    Keywords: Surgical sewing device ; Gastrointestinal anastomosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Eine neuartige chirurgische Nähmaschine für fortlaufende, mit Nadel und Faden ausgeführte, gastrointestinale Nahtverbindungen wurde erstmals zur Herstellung einer laterolateralen Enterostomie (funktionelle End-zu-End-Anastomose) am Schweinedünndarm eingesetzt. Bei 10 Tieren traten während des Beobachtungszeitraums von 10 Tagen keine wesentlichen Komplikationen auf. Bei einem Tier fand sich eine Nahtinsuffizienz. In 5 Fällen belegte die Sektion eine Deckung der Anastomosenregion mit Dünndarmschlingen, ohne daß sich jedoch ein eindeutiger Anhalt fur eine gedeckte Insuffizienz ergab. Die Nähmaschine arbeitete im wesentlichen fehlerfrei. Ein klinischer Einsatz erscheint derzeit z. B. bei der Fertigung langstreckiger und bei Handnaht zeitaufwendiger Nahtverbindungen zwar denkbar, ist aber aufgrund technischer Probleme noch verfrüht. Ein deutlicher Nachteil besteht u. a. in der Größe der Maschine und der daraus resultierenden Beschränkung auf extraabdominelle Anwendungen. Dennoch ist das Prinzip einer fortlaufenden Naht mittels Nähmaschine weiter zu verfolgen.
    Notes: Abstract A new surgical sewing device for continuous sutures of gastrointestinal anastomoses with needle and suture material was used for the first time to construct a latero-lateral enterostomy (functional end-to-end anastomosis) in the small intestine of pigs. In ten animals the course was mainly uneventful during the observation period of 10 days. One animal developed a postoperative anastomotic leakage. In five cases adhesions between the anastomotic region and the small intenstine were found on postmortem examination, but there was no evidence of any slight leakage. On the whole, the sewing device operated faultlessly. At present, clinical use seems possible for long sutures, which are time-consuming when sewn manually, but it is still premature. One major disadvantage of the device is its size, which restricts its application to extra-abdominal tasks. Nonetheless, the principle of a mechanical device for running sutures should be investigated further.
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  • 31
    ISSN: 1435-2451
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 32
    ISSN: 1435-2451
    Keywords: Benign pleural mesothelioma ; Localized ; Diagnosis ; Surgical management ; Prognosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Das benigne Pleuramesotheliom ist ein sehr seltener Tumor, für deren Ursprung die Mesothelien, aber auch das submesotheliale Bindegewebe diskutiert wird. Daher werden these Tumoren in der Literatur u. a. auch als Pleurafibrom, submesotheliales Fibrom, lokalisiertes fibröses Mesotheliom und monophasischer Spindelzelltumor beschrieben. Das Wachstum dieser Tumoren ist sehr langsam und geht über Jahre his Jahrzehnte. Im Gegensatz zum häufiger auftretenden malignen Pleuramesotheliom ist ein gehäuftes Auftreten nach Asbestex-position nicht zu beobachten. Wir berichten über eine 47jährige Patientin mit einem großen benignen Pleuramesotheliom im Bereich des rechten Thorax.
    Notes: Abstract Benign mesothelioma of the pleura is a very rare tumor. The cells responsible originate from either the mesothelium or the submesothelium. This is why such tumors are described in the literature as fibroma of the pleura, mesothelial fibroma, localized fibrous mesothelioma and monophasic spindle cell tumor. Their growth, is very slow taking several years or even decades. In contrast to the more common malignant mesothelioma of the pleura, it is not related to asbestos exposure. This report deals with a 47-year-old woman patient with a giant benign mesothelioma of the pleura in the region of the right thorax, which was completely removed by thoracotomy.
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  • 33
    ISSN: 1435-2451
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 34
    ISSN: 1435-2451
    Keywords: Liver transplantion ; Preservation ; Osmotic substances ; Preservation solutions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Zur Konservierung der Leber im Rahmen der Transplantation werden den Konservierungslösungen Osmotika zugesetzt. Diese sollen das hypoxisch bedingte Parenchymödem mit konsekutiven Mikrozirkulationsstörungen im Organ nach der Reperfusion verringern. Die Osmotika Mannit, Sucrose und Raffinose sowie das impermeable Laktobionatanion, die als Zusätke zu etablierten Leberkonservierungslösungen bereits klinische Anwendung finden, werden in einem In-vitro-Modell selektiv getestet. Isotone Konservierungslösungen mit unterschiedlich hohen Konzentrationen der Osmotika (60, 140, 260, 300 mmol/l) wurden verglichen. Die Lösungen wurden im Modell der Adhäsionskultur mit Hepatozyten aus Schweinelebern unter kalten hypoxischen Bedingungen (4°C; pO2< 0,1 mmHg) für 24 h inkubiert und über 3 h reoxygeniert. Zur Darstellung des Einflusses der verschiedenen Konservierungslösungen auf das Zellvolumen wurden die Lösungen im Modell der Suspensionskultur inkubiert und das Volumen der Zellzentrifugate nach 24 h kalter Hypoxie qualitativ verglichen. Die LDH- und GOT-Freisetzungsraten im Modell der Adhäsionskultur waren insgesamt mit aufsteigender Konzentration von Osmotika vermehrt. Die Ergebnisse bei Zusatz von 60 mmol/l Sucrose bzw. Raffinose waren mit den Konservierungsergebnissen bei Verwendung einer reinen extrazellulären Elektrolytlösung vergleichbar. Mannitzusatz zum Konservierungsmedium hatte einen deutlichen zellschädigenden Einfluß. Bei höheren Konzentrationen führte Sucrose zu einem geringeren Konservierungsschaden als Raffinose. Im Gegensatz zur Mannitlösung, die zu einer Zellschwellung führte, zeigten Sucrose und stärker noch Raffinose einen konzentrationsabhängigen volumenmindernden Effekt auf Hepatozyten in Suspension. Ein stark volumen-mindernder Effekt, beispielsweise durch hohe Sucroseoder Raffinosekonzentrationen, scheint eine zellschädogende Wirkung zu haben, so daß der Osmotikazusatz in Leberkonservierungslösungen entweder gering zu halten ist (≤60 mmol/l Sucrose bzw. Raffinose) oder vollständig durch ein Kolloid, das aufgrund seines Molekulargewichts nicht ins Intersitium gelangt, ersetzt werden könnte.
    Notes: Abstract To avoid hypoxic cell swelling during liver preservation followed by reduced perfusion in the reoxygenation period, osmotic substances such as mannitol, sucrose and raffinose, and the impermeant anion lactobionate are used in established liver preservation solutions. The various osmotic agents were investigated at concentrations of 60, 140, 260 and 300 mM, the solutions being kept isotonic by substitution with sodium and potassium chloride to 300 mosmol/l. Cultures of adherent pig hepatocytes were incubated in an in vitro model of cold hypoxia (4°C, PO2< 0.1 mmHg) for 24 h and reoxygenated with standard culture medium for 3 h. After each incubation period, light microscopy was performed to estimate cell viability and detachment rate. LDH and GOT liberation were also measured. To estimate the change in cell volume, isolated hepatocytes were incubated in suspension for 24 h of cold hypoxia. The cell volumes were compared after centrifugation and measurement of the pellet and the solute levels. Rising concentrations of osmotic substances resulted in increasing liberation of LDH and GOT. The levels of LDH and GOT release from cultures incubated with 60 mmol/l sucrose or raffinose were comparable to those in a preservation solution of “extracellular” ion composition. Addition of mannitol to the preservation solution resulted in cell damage. At high concentrations, sucrose did not affect the hepatocytes as much as raffinose. While mannitol can permeate the hepatocytes and lead to cell swelling, a cell-shrinking effect was observed when sucrose was used, and even more pronounced cell shrinking was seen with raffinose, to which the hepatocyte membrane is known to be permeable. With regard to the rise in enzyme release with increasing concentrations of osmotic agents, cell shrinking does not seem to correlate with better cell function or higher cell integrity. The content of investigated osmotic substances in liver preservation solutions should be less than 60 mM. Alternatively they could be substituted by a colloid, which cannot permeate the interstitial space.
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  • 35
    ISSN: 1435-2451
    Keywords: Liver metastases ; Liver resection ; Regional chemotherapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In einem Zeitraum von 7 Jahren wurden 151 Patienten mit Lebermetastasen verschiedener Primartumoren durch Leberresektion and/oder regionale Chemotherapie behandelt. Aufgrund der Heterogenität and geringen Zahl der übrigen Primartumoren wurden Patienten mit kolorektalem Karzinom gesondert betrachtet. Die beste Prognose wurde durch eine potentiell kurative Resektion mit einer 5-Jahres-Überlebensrate von 17% erzielt. Einziger signifikanter and unabhängiger Prognoseparameter war neben der Radikalität das Intervall zwischen Primärtumoroperation and Auftreten der Metastasierung. Durch eine adjuvante regionale Chemotherapie konme kein zusätzlicher Prognosegewinn nach kurativer Resektion erzielt werden. Die alleinige regionale Chemotherapie bei diffuser hepatischer Metastasierung führte ebenso wie die additive regionale oder systemdsche Chemotherapie nach palliativer Leberresektion zu keiner signifikanten Verlängerung der Überlebenszeiten.
    Notes: Abstract In a period of 7 years, 151 patients were treated by resection and/or regional chemotherapy after liver metastases from various primary tumours. The subgroup of patients with colorectal liver metastases was evaluated separately from the heterogeneous group with any other primaries. Radical resection of colorectal liver metastases was followed by a 5-year survival of 17%. The time from resection of the primary to development of the metastatic lesions was shown by univariate and multivariate analysis to be the most important prognostic factor. Adjuvant regional chemotherapy failed to improve outcome after curative resection of liver metastases. Neither palliative regional chemotherapy in cases of diffuse hepatic metastases nor the combination of palliative resection with regional or systemic chemotherapy significantly prolonged survival.
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  • 36
    ISSN: 1435-2451
    Keywords: Risk research ; Risk factors in surgery ; Elective surgery ; General surgery
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Seit 1988 wurden alle Patienten, welche einem elektiven viszeralchirurgischen Eingriff in Allgemeinnarkose oder rückenmarknaher Andsthesie unterzogen wurden in eine prospektive Studie aufgenommen, mit dem Ziel der praoperativen Risikoerfassung [5]. Das Risiko wurde in die folgenden Risikofaktorengruppen eingeteilt: Krankheit, Patient, Chirurg, operatives Umfeld, Operation per se. Vom 1.1.1990 bis 31.12.1990 wurden insgesamt 682 Patienten, 365 Manner and 317 Frauen in der Studie aufgenommen mit einem Durchschnittsalter von 59,1 Jahren (Bereich 14-90). Peri- oder postoperativ traten bei 63 Patienten (9,2%) allgemeine Komplikationen, bei 73 Patienten (10,7 %) lokale Komplikationen auf. Signifikante Risikoparameter fur allgemeine Komplikationen ware Alter ≥70 Jahre, arterielle Hypertonie, Hdmatokrit <40 % (bei Männern), maligne Grunderkrankung, eingeschrdnkte Leistungsfdhigkeit, pathologische kardiopulmonale Anamnese, pathologisches EKG, Alkoholabusus, Hepatosplenomegalie, ausländische Nationalität und ein Strömungsgeräusch der A. carotis. Die postoperative 30-Tageletalitdt betrug in unserem Krankengut 0,73%. Alle 5 Patienten litten an einer malignen Grundkrankheit, wobei 4mal palliativ und einmal in kurativer Absicht operiert wurde. Drei Todesfdlle wurden dem Hauptrisikofaktor “Krankheit”, je ein Todesfall dem Hauptrisikofaktor “Chirurg” “oder Patient” zugeordnet. Die vorliegende prospektive Risikoevaluation elektiver viszeralchirurgischer Eingriffe ist ein brauchbares Instrument zur Definition von praoperativen Riskofaktoren mit dem Ziel der Elimination der peri- and postoperativen Letalitdt.
    Notes: Abstract Since 1988 we have been analysing all our patients undergoing elective general surgery with general or spinal anaesthesia in a prospective study, with the aim of identifying and weighing up risk factors. The risk factors have been divided into the following groups: environment, surgeon, anaesthesia, operative intervention, disease and patient, regardless of the current illness. In 1990 a total of 682 patients (mean age 51.6 years, range 14–90), 365 male and 317 female, entered on study. General complications have been recorded in 63 patients (9.2%), whereas local complications occurred in 73 patients (10.7%). The following parameters were identified as risk factors for general complications: age >>-70 years, hypertensive blood pressure level, haemotocrit <40% (male patients), operative procedure for malignancies, reduced physical capacity, pathologic cardiac or lung history, pathologic ECG, excessive alcohol consumption, hepatosplenomegaly, foreign origin, carotid artery bruit. Five patients died within 30 days following surgery for a malignant disease. This ongoing prospective study is a valuable instrument for the definition of preoperative risk factors in elective general surgery with the objective of eliminating mortality by the end of the century.
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  • 37
    ISSN: 1435-2451
    Keywords: Appendicitis ; Ultrasound studies ; Diagnosis ; Prospective trial ; Laparotomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Am Departement Chirurgie des Universitätsspitals Zürich wurden zwischen 1. Dezember 1990 und 31 Dezember 1992 302 Patienten mit klinischer Verdachtsdiagnose “akute Appendizitis” ausschließlich von 7 Chirurgen sonographisch beurteilt, wobei der “Instruktor” ein Chirurg mit mehrjdhriger Erfahrung in sonographischen Untersuchungstechniken war. Von den untersuchten Patienten/innen wurden 139 (46%) laparotomiert. 119 (39,4%) zeigten intraoperativ und histologisch eine Appendizitis, wovon klinisch 87 (28,8%), sonographisch 119 (39,4%) in der Erstbeurteilung als eindeutig positiv beurteilt wurden. Sonographisch falsch-positive und falsch-negative stellten sich bei je 10 (3,3%) Patienten heraus. Bei den 163 Patienten die nicht operiert werden mußten, konnte 60mal (19,9%) sonographisch eine andere Diagnose gestellt wurden. Bei negativen Sonographien, negativer oder fraglicher Klinik führte die klinische Beurteilung des Stationsoberarztes zur Operationsindikation. Zu “Negativlaparotomien” kam es bei kombinierter Beurteilung bei 10 (7,2%) Patienten. Für das ganze Sonographieteam betrugen Sensitivität und Spezifität 92 bzw. 95% und für die Klinik alleine 81 bzw. 80%. Die absolute Trefferquote der Sonographie betrug 92%. Die Sensitivität und Spezifität der 6 angelermen Chirurgen betrug 87 und 93%. Die Sonographie erreichte in der Hand der Chirurgen somit vergleichbare Resultate mit denen der Sonographiespezialisten und hat in unserer Klinik deshalb ihren festen Platz in der Abkldrung der akuten Appendizitis eingenommen.
    Notes: Abstract A number of studies have shown that ultrasound has an advantage over physical examination in the diagnosis of acute appendicitis. Most of these studies were conducted by experts in the field of ultrasonography. In this study the influence of experience on the results of the sonography of actue appendicitis were evaluated. All 203 patients admitted to our unit between December 1990 and December 1992 were examined physically and sonographically by a team of surgeons consisting of one experienced sonographer and six inexperienced surgical trainees. Laparotomy was performed in 136 patients (46%). Appendicitis was demonstrated histologically in 119 cases (39.4%). Initial clinical findings were positive in 87 (28.8%). Sonography was positive in 119 patients (39.4%). The 163 patients not operated on demonstrated other pathology on ultrasound in 60 cases (19.9%). The rate of negative laparotomies amounted to 7.2% in our study. Sensitivity and specificity for the sonographic diagnosis were 92% and 95%, respectively. They were only 81% and 80% for physical examination. Overall accuracy was 92% for sonography. Sensitivity and specificity for the inexperienced surgeons were 87% and 93%, respectively, while the experienced surgeon reached values of 97% and 98%, respectively. The results of both groups are comparable with values in the literature, suggesting that ultrasound evaluation of appendicitis is not a diagnostic tool limited to a few experienced sonographers.
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  • 38
    ISSN: 1435-2451
    Keywords: Peritonitis ; Prognosis ; Mannheim Peritonitis-Index ; APACHE II ; Validation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Zur Beurteilung des Schweregrads und der Prognose einer Peritonitis werden objektive Scores gefordert. Der Mannheimer Peritonitis-Index ist ein krankheitsspezifischer Score, der auf einfach zu erhebenden klinischen Parametern beruht. Der APACHE 11 ist ein allgemeiner intensivmedizinischer Score, der aufwendige akute physiologische und chronische Parameter beruücksichtigt. Der Wert der beiden Systeme im Hinblick auf ihre Fähigkeit zur Risikoklassifikation und Prognosevorhersage sollte in der klinischen Anwendung gepruft werden. Hierzu werden 108 Patienten mit schwerer abdominaler Infektion und offener Abdomenbehandlung im Elahmen einer prospektiven Studie ausgewertet. 32 Patienten (29,6%) starben, davon 23 an der Sepsis, 9 aus anderer Ursache. Sowohl der MPI als auch der APACHE II zeigten eine enge Korrelation mit der Letalitat, dabei konnten jeweils 3 bzw. 2 signifikant verschiedene Punktegruppen abgegrenzt werden. Beim MP1 betrug die Sensitivitat 93%, die Spezifitat 16%, die Richtigkeit 71%, beim APACHE II entsprechend 89%, 25% und 71%. Die ROC-Kurven der Scores verliefen dementsprechend fast parallel. Zusammenfassend ergaben sich zwischen dem einfach zu erhebenden MPI und dem wesentlich aufwendigeren APACHE II keine wesentlichen Unterschiede im Hinblick auf die Fähigkeit zur Risikoklassifikation und Prognosevorhersage.
    Notes: Abstract Scoring systems are mandatory to quantify the severity of abdominal sepsis on the basis of objective criteria. The Mannheim Peritonitis Index (MPI) is a disease-specific score based on easy to handle clinical parameters. APACHE II is a large-scale general scoring system with acute physiological and chronic health parameters. To evaluate the prognostic value of both systems 108 patients with severe abdominal infection managed by open treatment entered a prospective study. 32 patients (29.6%) died, 23 of them due to sepsis and 9 from other causes. Both MPI and APACHE II scores correlated closely with mortality, with three and two significantly different classes, respectively. Statistical validation showed a sensitivity of 93% and a specificity of 16% for MPI, and 89% and 25% for the APACHE 11. ROC curves were nearly parallel for both scores. In conclusion there was no significant difference in prognostic value between the scoring systems.
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  • 39
    Electronic Resource
    Springer
    Langenbeck's archives of surgery 379 (1994), S. 358-360 
    ISSN: 1435-2451
    Keywords: Alimentary tract duplication ; Diagnosis ; Laparoscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Gastrointestinale Duplikaturen sind seltene Erkrankungen, die meist im Kindesalter symptomatisch werden. Häufig werden sie durch den palpablen Tumor diagnostiziert. Hauptkomplikationen sind Blutung, Perforation, Ileus oder Pankreatitis. Meist sind die Duplikaturen im Dünndarm lokalisiert. Eine eindeutige Diagnosestellung ist mittels bildgebender Verfahren kaum möglich. Eine maligne Entartung ist nicht bekannt. Die Indikation zur Resektion ergibt sick bei Vorliegen von Symptomen der Duplikaturen.
    Notes: Abstract Duplications of the alimentary tract are rare. Most of them are diagnosed during infancy or childhood, when they become symptomatic and a palpable mass is found. Major complications are bleeding, perforation, ileus and pancreatitis. In the majority of cases the gastrointestinal duplication is localized in the small bowel. Correct preoperative diagnosis by means of imaging techniques is rare. Because there is no malignancy surgery is only necessary in symptomatic cases.
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  • 40
    ISSN: 1435-2451
    Keywords: Colorectal carcinoma ; Adjuvant chemotherapy ; Adjuvant radiotherapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In der Arbeit werden bisherige und aktuelle Konzepte der adjuvanten Chemo- und Radiotherapie in einer Übersicht dargestellt. Nach frühen Chemotherapiestudien mit systemischem Einsatz verschiedener Einzelsubstanzen folgten Versuche, die therapeutische Effizienz durch Wirkstoffkombinationen zu steigern. 5-FU erwies sich als relativ wirkungsvollste Einzelsubstanz, 5-FU/MeCCNU/Vincristin als wirksamste Kombination. Verbesserungen der Fünfjahresüberlebensraten konnten nur vereinzelt erzielt werden. Einen deuthchen Fortschritt erbrachte die Modulation der 5-FU-Wirkung durch Levamisol (LEV). Hierdurch wurde fur Kolonkarzinome im Stadium Dukes C eine Verbesserung der Fünfjahres-überlebensrate um 33% erzielt. Basierend auf diesen Daten wird empfohlen, alle Kolonkarzinompatienten im Stadium III mit 5-FU/LEV zu behandeln, soweit sie nicht einer aktuellen Adjuvansstudie zugeführt werden können. Der Empfehlung kann his heute noch keine weitere allgemeine Richtlinie hinzugefügt werden. Beim Rektumkarzinom kann durch prdoperative Radiotherapie ein Down-Staging nach Dosen von 35-45 Gy erzielt werden. Eine signifikant positive Beeinflussung der Überlebens-prognose ist jedoch weder durch eine alleinige prä- noch postoperative adjuvante Bestrahlung überzeugend dokumentiert. Demgegenüber konnten durch kombinierte postoperative Radio-Chemo-Therapien (5-FU/MeCCNU) sowohl verbesserte Überlebensraten als auch eine verbesserte lokale Tumorkontrolle im Vergleich mit der alleinigen Resektion aufgezeigt werden. Es besteht die Empfehlung, alle Rektumkarzinompatienten im Stadium II und III einer kombinierten Radio-Chemo-Therapie unter Studienbedingungen zuzuführen. Als effektivste Chemotherapie in Verbindung mit Radiatio gilt 5-FU/MeCCNU. Interimsergebnisse deuten jedoch darauf hin, daß MeCCNU verzichtbar ist. Die intraoperative Radiatio (IORT) erlaubt eine Dosiseskalation zur Optimierung der lokalen Tumorkontrolle bei maximaler Schonung strahlensensibler Strukturen. Bisher liegen noch wenig Ergebnisse vor. Eine generelle Wertung der IORT im Rahmen adjuvanter Konzepte ist noch nicht möglich. Die bisherigen Daten sind jedoch erfolgversprechend.
    Notes: Abstract A review is given of the historical and current concepts of adjuvant chemo- and radiotherapy of colorectal cancer. Early studies analyzing the use of single drug regimens were followed by a second study generation investigating adjuvant chemotherapeutic combinations. 5-FU proved to be the most efficient single drug investigated and 5-FU/MeCCNU/vincristin the most efficient chemotherapeutic combination, but no significant improvement in 5-year survival rates was achieved. Clear progress was noted with the introduction of levamisol (LEV) for modulation of 5-FU. A 33% improval in the 5-year survival rate in patients with stage III colon carcinoma was documented. It was therefore recommended (NIH consensus conference 1990) that all patients with stage III colon carcinoma be treated with this regimen unless admitted to other trials of adjuvant therapy. Preoperative radiotherapy with a dosage of 35–45 Gy can lead to downstaging of rectal cancer. Nevertheless, significant improvement in patient survival has not been proved convincingly using either isolated pre- or postoperative adjuvant radiotherapy. However, combined radiochemotherapy has been shown to improve both patient survival and local tumor control compared to surgical resection alone. It is therefore recommended that all stage II and III rectal cancer patients be treated with adjuvant combined radiochemotherapy. 5-FU/MeCCNU is currently expected to be the most efficient chemotherapy in combination with radiotherapy. Early data point out that MeCCNU could possibly be omitted. Intraoperative radiotherapy (IORT) allows further dosage escalation in order to improve local tumor control without affecting radiosensitive structures. Available data are still sparse and mostly based on the treatment of advanced carcinoma. A general validation of IORT is not yet possible, but current data are promising.
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  • 41
    ISSN: 1435-2451
    Keywords: Primary sarcoma of the liver ; Surgical therapy ; Prognostic factors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Im Zeitraum von 1985 bis Januar 1994 wurden an der Chirurgischen Universitätsklinik Hamburg-Eppendorf 11 erwachsene Patienten mit primären Sarkomen der Leber operiert. Achtmal konnte der Tumor R0 reseziert werden, davon einmal im Rahmen einer Lebertransplantation. Drei Patienten wurden primär R1-reseziert. Zum Abschluß der Untersuchungen leben nach im Mittel 57 (5–104) Monaten 7 R0-resezierte Patienten tumorfrei. Bei der lebertransplantierten Patientin traten 31 Monate nach Diagnosestellung Metastasen auf. Zwei der Patienten mit primärer R1-Resektion starben nach 30 bzw. 35 Monaten, einer lebt 7 Monate nach Diagnosestellung tumorfrei. Patienten mit nichtmetastasierten, primären Lebersarkomen können einen langfristigen Verlauf erwarten, wenn der Tumor im Rahmen einer anatomischen Leberresektion mit weitem Sicherheitsabstand entfernt wird. Bei multifokalem Befall der Leber kann eine Lebertransplantation erwogen werden.
    Notes: Abstract Eleven adult patients with primary sarcoma of the liver underwent surgery at the University Hospital of Hamburg-Eppendorf between 1985 and January 1994. In 8 cases it was possible to resect the tumor with wide margins (R0), in 1 of these in the course of orthotopic liver transplantation. Three patients had primarily marginal resection (R1). By the end of the study period 7 of the patients who underwent initial RO resection are tumor-free, with a mean survival time of 57 (5–104) months. The patient with orthotopic liver transplantation developed metastases 31 months after primary surgery. At 7 months after initial R1 resection, 1 patient is alive with no evidence of disease while 2 others died after 30 and 35 months, respectively. Patients with non-metastasized, primary sarcomas of the liver can expect long-term survival if the tumor is resected with wide margins in an anatomical hepatectomy. In the case of multifocal growth in the liver transplantation can be considered.
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  • 42
    ISSN: 1435-2451
    Keywords: Intestinal ecology ; Muscular sphincter-replacement ; Ultrasonic tissue fragmentation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Experimentell wurde em intestinaler Neosphinkter (INS) aus 3 Muskelschichten konstruiert. Dazu wurde das Prinzip der ileokolischen Nippel-Valve-Anastomose dahingehend abgewandelt. daß die kontaktierende Serosa des Ileums und die korrespondierende Mukosa von Ileum und Kolon durch Ultraschallfragmentation entfernt werden. Die dadurch beabsichtigte kompakte Verheilung der Muskelschichten wurde histomorphologisch kontrolliert. Die Funktion des intestinalen Neosphinkters als Ileozäkalklappenersatz wurde im intraindividuellen Vergleich bei 6 Hunden überprüft. Morphologisch waren die Neosphinkteren nach 3 Monaten ohne verstärkte Fibrosebildung stabil verheilt. Die Referenzwerte der Keimbesiedlung im terminalen Ileum lagen bei der physiologischen Ileozäkalklappe für aerobe und anaerobe Keime im Median deutlich um mehr als 2 Zehnerpotenzen niedriger als im Kolon, wobei dieser Unterschied nur bei den anaeroben Keimzahlen statistisch signifikant war (p<0,05). Während nach Resektion der Ileozäkalklappe und Anlage einer End-zu-End-Anastomose qualitativ und quantitativ die bakterielle Kolonisation des Ileums nachgewiesen wurde, führte die danach erfolgte Interposition des Neosphinkters wieder zur mikrobiellen Clearance des terminalen Ileums. Die medianen aeroben Keimzahlen sanken um 6 Zehnerpotenzen gegenüber dem Kolon, die anaeroben um 3 Zehnerpotenzen. Obwohl die mediane Keimreduzierung im terminalen Ileum beim Neosphinkter damit besser war als bei der physiologischen Ileozäkalklappe, konnte eine statistische Signifikanz wegen großer Streubreiten der Einzelwerte nicht gesichert werden. Die trotzdem nachweisbare Clearance des terminalen Ileums wird durch die absolut stagnationsfreie orthograde Durchgängigkeit und die relative (his 100 cm Bariumsäule) retrograde Druckkompetenz des Neosphinkters erklärt. Mit Hilfe der Ultraschallfragmentation von Serosa und Mukosa des Darmes läßt sich ein mehrschichtiger muskulärer intestinaler Neosphinkter herstellen, der eine bakterielle Milieutrennung zwischen verschiedenen Darmabschnitten erzeugt. Vor klinischer Einführung als Ileozäkalklappenersatz bei Kurzdarmsyndrom sollte die Integration in die intestinale Motilität durch weitere experimentelle Studien erhärtet werden.
    Notes: Abstract In an experimental study an intestinal neosphincter (INS) was constructed by modifying the principle of the ileocolic nipple-valve anastomosis by means of ultrasonic tissue fragmentation of the contacting serosa of the ileum and the corresponding mucosa of the ileum and colon. The healing of the muscle layers was studied histologically. The function of the INS was investigated in six dogs and compared intraindividually with that of the ileocecal valve and conventional end-to-end anastomosis. Morphologically the neospincters healed within 3 months without major fibrosis. The reference values of the aerobic and anaerobic bacterial counts in the terminal ileum were more than 2 logs lower than in the colon with the normal ileocecal valve, and after ileo-colonic end-to-end anastomosis bacterial colonization of the terminal ileum was found both qualitatively and quantitatively. Subsequent interposition of the INS led to bacterial clearance of the terminal ileum. The median aerobic bacterial counts were lower by six logs and the an aerobic bacterial counts by 3 logs than in the colon. However, differences were not statistically significant owing to the wide variation in the individual values. Nevertheless, the demonstrable clearance of the terminal ileum could be explained by the orthograde passage with absolutely no stagnation and the relative competence of the INS in resisting retrograde pressure competence. In conclusion, ultrasonic fragmentation of the serosa and mucosa of the bowel allows construction of an INS from three muscle layers, which acts as a bacteriological barrier. Before it is introduced into the clinical setting its integration into the intestinal motility should be evaluated by further studies.
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  • 43
    ISSN: 1435-2451
    Keywords: Lebertransplantation-Infektion-Pilze ; Aspergillus ; Candida
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Abstract A retrospective analysis of 462 consecutive orthotopic liver transplantations was undertaken to evaluate incidence, risk factors, clinical course, and outcome of fungal infections. Infections involving Aspergillus (6 cases), Candida (5 cases), Mucor (1 case), and Cryptococcus (1 case) were observed in 2.8% (13/462) of our patients. Twelve of the 13 episodes developed during the first 2 postoperative months. None of the potential risk factors for fungal infections described by other authors (i.e., age, rejection treatment, dialysis, mechanical ventilation, graft failure, long operation time, second transplant, serious nonfungal infection) correlated significantly with the episodes in our patients. However, in patients who exhibited three or more of these potential risk factors the incidence of fungal infections was elevated (P<0.001). Six of seven exogenous infections (Aspergillus, Mucor) began before July 1991 when our department moved from Charlottenburg to Wedding, thus indicating that the incidence of these infections is highly influenced by exposure (P=0.01). Exposure prophylaxis should therefore by meticulously followed, particularly when severely compromised patients are involved, in order to prevent exogenous infections (i.e., Aspergillus/Mucor). Infections involving such patients are combined with a very high mortality (57%). We observed Candida infection as a pathological overgrowth of physiological oropharynx flora into the esophagus and/or trachea in five patients. In each case treatment led to full recovery.
    Notes: Zusammenfassung Um Inzidenz, Risikofaktoren, klinischen Verlauf und Prognose von Pilzinfektionen nach Lebertransplantation zu klären, wurden die Verläufe von 462 Patienten retrospektiv untersucht, die zwischen Oktober 1988 und Februar 1994 konsekutiv transplantiert wurden. Bei 13 unserer Patienten (2,8%) beobachteten wir Infektionen mit Aspergillus (6mal), Candida (5mal), Mucor (1mal) und Cryptococcus (1mal) Dabei trat die Infektion bei 12 der 13 Patienten bereits während der ersten 2 postoperativen Monate auf. Von den von anderen Autoren beschriebenen potentiellen Risikofaktoren (Alter, Abstoßungsbehandlung, Dialyse, maschinelle Beatmung, Graftversagen, lange Operationszeit, Retransplantation, schwere Allgemeininfektion) korrelierte bei unseren Patienten keine einzige mit den Infektionen. Allerdings war die Inzidenz der Pilzinfektionen bei Patienten, die 3 oder mehr dieser Risikofaktoren zeigten, signifikant erhöht (p<0,001). Ferner traten 6 von 7 exogenen Infektionen (Aspergillus, Mucor) vor dem Umzug unserer Transplantationsstation aus dem 1. Stock eines alten, efeubewachsenen Ziegelbaus in den 7. Stock eines Neubaus im Juli 1991 auf (p=0,01). Dies zeigt, daß die Exposition die Inzidenz von Pilzinfektionen nach Lebertransplantation wesentlich beeinflußt. Daraus folgt, daß insbesondere schwer kompromittierte Patienten einer strengen Expositionsprophylaxe unterzogen wurden müssen, um Infektionen mit Aspelgillus/Mucor zu vermeiden, die bei unseren Patienten eine Letalität von 57% aufwiesen. Bei 5 Patienten beobachteten wir Candidainfektionen als pathologisches Überwuchern der oralen Standortflora in Trachea und/oder Speiseröhre, die unter Therapie ausnahmslos ausheilten.
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  • 44
    ISSN: 1435-2451
    Keywords: Mechanical stapling ; Absorbable staples ; Partial gastrectomy ; Duodenal stump
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Im Rahmen eines Tierexperiments wurden resorbierbare Laktomerklammern (Polyester auf Polyglykol/Polylaktatsäurebasis) bzgl. ihrer Sicherheit und Gewebeverträglichkeit bei Magenresektionen untersucht. Bei Hausschweinen erfolgten Magenresektionen nach Billroth I (n = 10) sowie Roux-Y (n = 12) unter Einsatz resorbierbarer Klammern zum partiellen Verschluß des Magens sowie zum Duodenalstumpfverschluß. Die Nachbeobachtungszeit betrug 12 Monate. In ihrer Anwendung erwiesen sich die mit resorbierbaren Klammern bestückten Nahtgeräte bzw. die resultierenden linearen Nahtreihen als technisch unproblematisch und sicher. Bei einem von 22 Tieren (4,5%) trat früh-postoperativ eine Insuffizienz im Bereich der kleinen Magenkurvatur auf. Makroskopisch verursachte das eingesetzte Klammermaterial keine übermäßige Umgebungsreaktion. Mikroskopisch ließ sich nach 12 Monaten die komplette Resorption des Klammermaterials nachweisen, ohne daß eine stärker ausgeprägte Narbenbildung zu verzeichnen war. Die erhobenen experimentellen Befunde ergaben keine Kontraindikation zur klinischen Anwendung resorbierbarer Klammernähte im Bereich des Gastrointestinaltraktes, wobei die vom Hersteller angekündigte Verkleinerung der Klammern vorteilhaft sein dürfte.
    Notes: Abstract In animal experiments with a 12-month follow-up, the safety and compatibility of absorbable staple lines following gastrointestinal surgery were analysed. In two groups of pigs, partial gastrectomies with gastroduodenostomy (Billroth I, n = 10) or gastrojejunostomy (Roux-en-Y, n = 12) were performed, and Lactomer — a copolymer of glycolic acid and lactic acid — staple lines were used for closure of the lesser curvature of the stomach and the duodenal stump. Application of the staple lines caused no problems and was safe. In 1 of the 22 pigs, which died of an ileus 9 days postoperatively a suture dehiscence (4.5 %) at the lesser curvature of the stomach was observed. Macroscopic examination showed no major inflammation around the staples. Microscopically complete absorption of the Lactomer staples without extensive scarification in the gastrointestinal wall could be demonstrated 12 months postoperatively. Our results yielded no contraindications for the clinical use of absorbable staple lines in gastrointestinal surgery. The manufacturer has given advance notice of smaller staples, which it is considered will be an advantage.
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  • 45
    ISSN: 1435-2451
    Keywords: Duplex Doppler ultrasound ; Liver transplantation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In einer prospektiven Untersuchung wurde an 44 Patienten (33 Männer, 11 Frauen) riach einer elektiven orthotopen Lebertransplantation die Duplexsonographie 196ma1 angewendet. Ziel der Untersuchung war es festzustellen, inwieweit and in welchem zeitlichen Zusammenhang sich die Parameter pulsatiler FluBindex (PFI) und Dämpfungsindex (DI) bei Komplikationen wie Abstoβung und Cholangitis verändern. Der Duplex-Doppler-Ultraschall wurde im Mittel 5mal pro Patient durchgeführt. Die letzte Sonographie erfolgte am Entlassungstag. Bei den Messungen fiber der Leberarterie, der Pfortader und den Lebervenen wurden jeweils der PFI und der DI bestimmt. Die Ergebnisse der Indexuntersuchungen wurden mit dem klinischen Verlauf (Abstoβung, Cholangitis) sowie mit den Resultaten von 88 Biopsiepräparaten der Lebertransplantate in Beziehung gesetzt. Bezüglich einer histologisch gesicherten AbstoBung ergab der PFI (über der Leberarterie gemessen) eine Sensitivität von 69,4 % and eine Spezifitdt von 72,2 %, der DI (über den Lebervenen gemessen) eine Sensitivität von 89,4% und eine Spezifitdt von 89,1 %. Wenn auch die einfach und beliebig oft anwendbare Untersuchungstechnik die bioptische Sicherung einer Rejektion nicht ersetzen kann, so ist sie in hohem Maβe in der Lage, Indikationen zur Biopsie frühzeitig stellen zu lassen und ein Ansprechen auf eine Therapie kurzfristig und mit holier Genauigkeit anzuzeigen.
    Notes: Abstract In a prospective study, 44 patients (11 women, 33 men) who had received orthotopic liver transplants underwent a total of 196 consecutive duplex Doppler ultrasound examinations. The aim of the study was to evaluate the correlation between the pulsatile flow index (PFI) and the damping index (DI) as far as complications as rejection or cholangitis were concerned. The patients were examined five times each on average. The PFI and DI were measured in the hepatic artery, the portal vein and the hepatic veins. The findings were compared with the clinical course (cholangitis, rejection) and the histomorphological diagnosis as determined in biopsy specimens. In biopsy-proven rejection episodes, the sensitivity of the PFI in the hepatic artery was 69.4%, the specificity 72.2%. The sensitivity of the DI in the hepatic vein was 89.4%, the specificity 89.1 %. Combining the two, specificity was more than 90%. PFI and DI in the portal vein bore no apparent relation to clinical course or histomorphological diagnosis. We found duplex Doppler ultrasound extremely beneficial in determining the timing and indication for liver biopsy. In addition, this simple examination, which can be performed as often as desired, accurately shows the transplanted liver's response to measures taken to counter rejection.
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  • 46
    ISSN: 1435-2451
    Keywords: Abdominal wall defect ; Skin plasty technique ; Morphology ; Wound healing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In einer tierexperimentellen Untersuchung wurde die Einheilung und Morphologie der Kutisplastik nach Loewe [11] und Rehn [17] unter verschiedenen Einheilungsbedingungen geprüft. Untersucht werden sollten der Mechanismus and Ablauf der Revaskularisation und die Phasen der Einheilung. Ergebnisse: Die Einheilung erfolgt über die Ausbildung einer fibrinösen Einscheidung der Kutisplastik mit nachfolgender Entwicklung eines Granulationsgewebe. Zwei Mechanismen laufen anschlieβend parallel nebeneinander ab. Zunächst kommt es zur Revaskularisation von alien Seiten der Plastik über Kapillaren and Gefäβe in die Netzmatrix des Koriums. An dieser Stelle könntn sich die Gefäβe parallel der Fasern schnell ausbreiten oder erhalten Anschluβ an das vorhandene Gefäβsystem. Kapillaren sind innerhalb von 3 bis 4 Tagen nachzuweisen. Nach 14 Tagen ist die Gefäβversorgung des Transplantats abgeschlossen. Im weiteren wandern Granulozyten und Makrophagen in das Transplantat ein. Diese lösen alle Bestandteile der Kutis, zuerst Epidermis and Hautanhangsgebilde später das Netzwerk des Koriums, auf. Es folgt die Neuentwicklung eines kollagenen Fasersystems entsprechend der funktionellen Beanspruchung iiber ein gerichtetes Granulations- und Narbengewebe. In diesem bilden Fibroblasten erneut kollagene Fasern aus. Die Kutisplastik wird mit der Epidermisseite zum Peritoneum eingebracht und unter maximaler Zugspannung an der Faszie befestigt. Nur unter der angelegten Spannung — so konnte tierexperimentell nachgewiesen werden — erfolgt die Einheilung regelrecht. Im Gegensatz zu alien anderen Nahttechniken in der Chirurgie ist die Spannung des Transplantats notwendige Voraussetzung.
    Notes: Abstract The aim of the experimental study was to investigate morphology and wound healing following the skin plasty (“Kutisplastik”) technique originally introduced by Loewe [11] and Rehn [17] under different conditions. We wanted to clarify the mechanism and development of revascularisation. Results: The familiar phases of wound healing take the usual course after a skin plasty. In the exsudative reaction the cutis is covered with fibrin fibres. This leads to the development of granulation tissue. The cellular reaction takes place in two parts: first comes the ingrowth of capillary bundles and vessels in the collagen network of corium; revascularization is complete within 14 days after the operation. This is followed by the immigration of granulocytes and macrophages into the graft. The release of enzymes leads to the lysis of epidermal structures, cutaneous appendages and ultimately to collagen fibres of corium. There is also proliferation from fibroblasts. Genesis from new collagen fibres is then observed as scar tissue. The skin plasty technique involves turning the epidermal side of the graft to the peritoneum and suturing it under the highest tension possible to the surrounding healthy fascia. This course of healing is seen only with such high-tension suturing. Experimental nontension suturing has led to failure of skin plasty for abdominal wall defects.
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  • 47
    ISSN: 1435-2451
    Keywords: Lower leg fracture ; Unreamed tibial nail (UTN)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Der unaufgebohrte Tibiamarknagel (UTN) vereinigt die Vorteile des Fixateur externe mit denen des Marknagels in der Behandlung der Unterschenkelfraktur [5]. In der Zeit von März 1992 bis März 1993 wurden 33 Frakturen (31 geschlossene and 2 offene) mit dem UTN stabilisiert. In 67% (22 Patienten) bestanden A1-, A2- and A3-Brüche gemäß der AO-Klassifikation. Sechsmal lag eine Mitbeteiligung des oberen Sprunggelenks vor. 27 Personen konnten durchschnittlich 6 Monate postoperativ nachuntersucht werden; 26 erzielten ein ausgezeichnetes klinisches Ergebnis. Die mittlere Konsolidierungszeit lag bei 12 bis 14 Wochen.
    Notes: Abstract The unreamed tibial nail (UTN) combines the advantages of the external fixator (preservation of the cortical blood supply) with that of conventional intramedullary nailing (closed system, high patient comfort, no pin problems) in the treatment of the lower leg fracture [5]. Within 1 year (III/92 to III/93) 31 closed and 2 open fractures were stabilised with UTN. In 67% (22 persons) we found fractures of the A1, A2 and A3 types according to the AO classification. In 6 patients there was a combined lesion with involvement of the ankle joint. A follow-up of 27 patients was done, extending to an average of 6 months postoperatively. The clinical and radiological results were excellent in 26; average fracture healing time was about 12–14 weeks.
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  • 48
    ISSN: 1435-2451
    Keywords: Congenital duodenal stenosis ; Adults ; Operative treatment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Eine hochgradige Duodenalstenose im Erwachsenenalter kann in seltenen Fällen angeboren sein und findet ihre Ursache in einer intraduodenal gelegenen Membran. Die Anamnese zeigt Wachstumsstörungen mit Erbrechen und Meteorismus und abdominelle Beschwerden. Eine Perforationsöffnung in dieser Membran ist die Ursache fur ein Überleben bis ins Erwachsenenalter. Die Röntgendarstellung und die tiefe Duodenoskopie lassen auf einfache Weise die Diagnose stellen. Differentialdiagnostisch müssen der Volvulus bei Malrotation, Ladd-Bänder und das Pancreas anulare, sowie die Kompression des Duodenums durch Mesenterialgefäße erwogen werden. Das operative Verfahren der Wahl ist die Resektion der intraduodenalen Membran. Dabei ist v. a. die Papilla Vateri darzustellen, da diese nicht selten im Bereich des Septums mündet. Das längs eröffnete Duodenum wird quer verschlossen. Bei der Wind-Sock-Web-Anomalie sollte das Duodenum an der Ansatzstelle des Diaphragmas eröffnet werden. Die Anlage einer Gastrojejunostomie ist inadäquat und zu vermeiden.
    Notes: Abstract A high-grade duodenal stenosis in adults can, in rare cases, be congenital, and its cause is found in an intraduodenally sited membrane. The anamnesis reveals growth disorders with vomiting and meteorism and abdominal complaints. A perforation opening in this membrane is the reason for survival into adulthood. The X-ray appearance and deep duodenoscopy make the diagnosis easy. Volvulus in cases of malrotation, Ladd's ligaments, anular pancreas, and compression of the duodenum by mesenteric vessels must be considered in the differential diagnosis. When the intraduodenal membrane is resected it is most important to expose the papilla Vateri, since this not uncommonly ends in the area of the septum. If necessary, a duodenoduodenostomy is performed. If the windsock web abnormality is present the duodenum should be opened at the point of attachment of the diaphragm. The construction of a gastrojejunostomy should be avoided.
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  • 49
    ISSN: 1435-2451
    Keywords: Primärer Hyperparathyreoidismus ; Chirurgie ; PTH (Parathormon)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die intraoperative Differentialdiagnose zwischen Adenom und Hyperplasie bereitet bei Eingriffen wegen primarem Hyperparathyreoidismus (pHPT) gelegentlich Schwierigkeiten. Es wurden verschiedene Methoden vorgeschlagen, nach denen der Chirurg entscheiden kann, wieviel parathyreoides Gewebe zu resezieren ist. Wir untersuchten bei 47 Patienten, die wegen pHPT operiert wurden, die Anwendung des intraoperativen Monitoring der intakten PTH-Sekretion. Der entsprechende hochsensitive PTH-Assay wurde modifiziert, damit ein komplettes Resultat von der Exzision an über 60 min zu erzielen war. Die Korrelation r zwischen den Ergebnissen nach modifizierter und konventioneller Methode (die eine 24-h-Inkubation erfordert) betrug 0,98. Die intakte PTH-Sekretion verringerte sich 15 min nach Entfernung des parathyreoiden Adenoms um 85 (11)% [Mittelwert (SD)]. Die Patienten mit parathyreoidem Adenom wiesen eine PTH-Verringerung von 63% auf; dies ließ bei den 4 Patienten mit primärer Hyperplasie zu 95% zuverlässig erkennen, daß sie kein parathyreoides Adenom hatten. Wir folgern daraus, daß die intraoperative Messung der PTH-Sekretion ein wichtiges chirurgisches Hilfsmittel (insbesondere bei Reoperationen) sein kann.
    Notes: Abstract The intraoperative differential diagnosis between adenoma and hyperplasia during surgery for primary hyperparathyroidism (pHPT) is sometimes difficult. Several methods have been proposed to aid the surgeon in deciding on the amount of parathyroid tissue to be resected. We examined the use of intraoperative monitoring of intact PTH in 47 patients operated upon for pHPT. The highly sensitive assay for intact PTH was modified to permit a total turn-around time from gland excision to obtained result of about 60 min. The correlation (r) between the results of the modified and the conventional method; which requires 24 h of incubation, was 0.98. At 15 min after removal of the parathyroid adenoma the levels of intact PTH had decreased by [mean (SD)] 85 (11)%. A decrease of 63% in intact PTH in patients with parathyroid adenoma predicted with 95% confidence the 4 patients with primary hyperplasia as not having parathyroid adenoma. We conclude that intraoperative measurement of intact PTH could be a valuable adjunct to surgical skill, especially for reoperative parathyroid surgery.
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  • 50
    ISSN: 1435-2451
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 51
    ISSN: 1435-2451
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 52
    ISSN: 1435-2451
    Keywords: Fracture of the head of radius ; Functional treatment ; Early results ; Computed tomography ; Treatment protocol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Den Vorteilen einer osteosynthetischen Versorgung einer Fraktur mit sofortiger Aufnahme seiner Funktion, stehen die aus der Literatur bekannten Komplikationen gegenüber. Diese und unsere eigenen unbefriedigenden Ergebnisse nach der operativen Versorgung von Radiusköpfchenfrakturen ließen uns zu einer prospektiven randomisierten Studie einer primär funktionellen Behandlung unter Verzicht auf eine äußere oder innere Stabilisierung greifen. Seit Dezember 1991 haben wir im UKH-Graz bis einschließlich Dezember 1992 insgesamt 70 Patienten nach einem strikten Behandlungskonzept, unter Zuhilfenahme der Computertomographie zur Verlaufsbeobachtung versorgt. Die in 91% der Fälle als sehr gut and gut einzustufenden Frühergebnisse sowie das fehlende Auftreten einer, wie bei operativer Versorgung möglichen Komplikation, ebenso die zusätzlich deutlich frühere Arbeitsfähigkeit bzw. deutlich kürzere, wenn auch aufwendigere Behandlungszeit, lassen uns diese Verfahren nicht nur in unserem Hans weiterführen, sondern können wir auch weiter empfehlen.
    Notes: Abstract The advantages of internal fixation of fractures, with the possibility of immediate resumption of the function of the fractured bone, are in contrast to the well-known complications described in the literature. These complications and our own unsatisfactory results after surgical treatment of fractures of the head of the radius induced us to carry out a randomized prospective study of primary functional treatment of such fractures without external or internal stabilization. From December 1991 through December 1992, a total of 70 patients were treated according to a strict treatment protocol at the Graz Hospital for Accident Surgery, and CT was used for observation of the healing process. The positive early results, which in 91% of all cases were classified as very good or good, the lack of complications that sometimes follow surgical treatment, the markedly earlier recovery of the patient's working capacity, and the clearly shorter — albeit somewhat more expensive — treatment period required have led us to continue using this method at our hospital and also to recommend its use elsewhere.
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  • 53
    ISSN: 1435-2451
    Keywords: Osteoarthrosis ; Rabbits ; Knee joint ; Holmium:YAG laser ; Laser surgery
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Das Ziel dieser Arbeit war, an einem Kaninchenarthrosemodell die Gewebereaktionen infolge einer Holmiumlaser-Knorpelabtragung, konventionellmechanischer Therapie und einer Scheinoperation nach unterschiedlichen postoperativen Zeiten zu untersuchen und vergleichend zu bewerten. Bei 27 Kaninchen wurde durch Implantation einer Polyäthylenfolie in ein Kniegelenk eine Arthrose induziert. Nach 5 Monaten hatten sich deutliche arthrotische Veränderungen entwickelt. Jeweils 9 Tiere wurden einer Scheinoperation, der konventionell-mechanischen Therapie oder der Holmiumlasertherapie unterzogen. Ein Tag, ein Monat und 3 Monate postoperativ wurden jeweils 3 Tiere aus jeder Gruppe getötet und die Gelenke makroskopisch und histologisch untersucht. Drei Monate nach der konventionell-mechanischen Therapie waren die Knorpeloberflächen relativ glatt und Einrisse und Defekte weitgehend durch Faserknorpel ersetzt. Im Gegensatz dazu zeigten sich nach der Lasertherapie regelmäßig deutliche Knorpelnekrosen, z. T. Deckplatteneinbrüche und entzündliche Veränderungen bis in den Markraum hinein. Die Gelenkflächen blieben aufgerauht und weitgehend uneben. Aufgrund dieser bisherigen Ergebnisse erscheint der Einsatz des Holmiumlasers zum flächenhaften Glätten, Versiegeln oder Modellieren von Knorpelarealen der konventionell-mechanischen Therapie nicht überlegen.
    Notes: Abstract The aim of this work was to investigate and evaluate the tissue reactions after sham operation and after mechanical and holmium laser chondral debridement in a rabbit model at different postoperative intervals. In 27 rabbits an arthrosis was induced by implantation of a piece of polyethylene sheeting in one knee joint. After 5 months, distinct arthritic changes had developed. Nine animals each were randomized for sham operation, mechanical debridement, and holmium laser chondral debridement. At 1 day, 1 month, and 3 months postoperatively, three animals in each group were sacrificed and their joints examined grossly and microscopically. At 3 months after mechanical debridement the articular surface was relatively smooth, and tears and defects were filled with fibrous repair tissue. After holmium laser debridement chondral necroses were regularly found, occasionally with damage to the subchondral bone and distinct inflammation in the marrow space. The articular surface remained rough and uneven. These preliminary results suggest that use of the holmium laser is not superior to mechanical methods for remodelling and smoothing of fairly large chondral areas.
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  • 54
    ISSN: 1435-2451
    Keywords: Adhesions ; Laparoscopy ; Laparotomy ; Cecal resection ; Animal study
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung An Hunden wurden laparoskopisch (n = 7) bzw. per Laparotomie (n = 7) nach Exploration des Dünndarms eine Zäkalpolresektion mit Endo-GIA bzw. TA-30 durchgeführt, 2 cm2 der lateralen Bauchwand deserosiert und ein Netzzipfel reseziert. Am B. postoperativen Tag wurden alle Tiere relaparotomiert und die entstandenen Adhäsionen rechnergestützt vermessen. Das Ausmaß der Adhäsionen nach laparoskopischen Eingriffen war signifikant (P < 0,01) geringer. Ausgedehnte Adhäsionen zur Laparotomiewunde und zwischen den Darmschlingen bedingten größere Adhäsionsflächen nach Laparotomie. Konglomeratadhäsionen, adhäsionsbedingte Darmabknickungen und Briden fanden sich häufiger nach konventionellen Operationen. Identische Manipulationen wie Zäkalresektion und Deserosierung der lateralen Bauchwand führten nach laparoskopischen und konventionellen Eingriffen zum gleichen Adhäsionsausmaß. Aufgrund unserer Ergebnisse ist das Risiko adhäsionsbedingter Komplikationen nach laparoskopischen Operationen insgesamt geringer als nach identischen konventionellen Eingriffen einzuschätzen.
    Notes: Abstract We performed laparoscopy (n = 7) or laparotomy (n = 7) for exploration of the small intestine, cecal resection with Endo-GIA or TA-30, deserosation of 2 cm2 of the abdominal wall and resection of the omenturn majus in dogs. After 8 days all dogs were re-examined and the adhesions were quantified by computer-aided measurement. Laparoscopic operations were followed by significantly (P < 0.001) fewer adhesions. After conventional operations extensive adhesions to the abdominal incision and interenteric adhesions were found, together with frequent conglomerates of adhesions, intestinal kinkings or adhesive bands. Identical manipulations, such as cecal resection or deserosation of the lateral abdominal wall, led to the same frequency and severity of adhesions in both groups. Based on our results, the risk of adhesion-related complications may be reduced by the laparoscopic approach.
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  • 55
    ISSN: 1435-2451
    Keywords: Superior vena cava syndrome ; Femoral vein transplantation ; Bypass material
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei einem 52jährigen, männlichen Patienten trat nach Implantation einer Insulinpumpe als Spätkomplikation eine Thrombose der Vena cava superior auf. Nach erfolgloser Lysetherapie wurde ein Venajugularis-rechtsatrialer-Venenbypass mit autologer Vena femoralis durchgeführt. Der postoperative Heilungsverlauf war sowohl von Seiten des gefäßrekonstruktiven Eingriffs, als auch von Seiten der Venenentnahmestelle komplikationslos. Der Bypass ist 7 Monate postoperativ offen und der Patient beschwerdefrei. Die autologe Vena femoralis eignet sich zur Rekonstruktion großer venöser Gefäße ausgezeichnet. Sie sollte v. a. bei benignen Prozessen und jüngeren Patienten als autologes Bypassmaterial dem Kunststoff vorgezogen werden. Das Ergebnis wird mit verschiedenen Gefäßsubstituten, die bei Verschluß der oberen Hohlvene verwendet werden, verglichen.
    Notes: Abstract We report on a 52-year old male patient who underwent implantation of an insulin pump because he had diabetes and in whom superior vena cava syndrome developed as a long-term complication. After unsuccessful lysis therapy superficial femoral vein was implanted to form a bypass from the internal jugular vein to the right atrium. The postoperative course was uneventful from the aspects of both the bypass and the leg after explantation of the superficial femoral vein. The bypass is still patent 7 months after the operation, and the patient has no symptoms. Autogenous superficial femoral vein can be used successfully in the reconstruction of large venous vessels. It should be the graft of choice for young patients with benign diseases. We compare our result and those obtained with different substitutes described in the literature that have been used for reconstruction in superior vena cava syndrome.
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  • 56
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    Langenbeck's archives of surgery 379 (1994), S. 129-130 
    ISSN: 1435-2451
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 57
    ISSN: 1435-2451
    Keywords: Peritonitis ; Prognosis ; Mannheim Peritonitis-Index ; Validation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Einfache klinische Parameter, wie sie im Mannheimer Peritonitis-Index (MPI) verwendet werden, wurden auf ihre Aussagekraft zur Prognose der Peritonitis (Hospitalletalität) geprüft und eine Validierung des MPI durch Bestimmung der Spezifität, Sensitivität und Richtigkeit durchgeführt. Das Therapiekonzept bei 438 prospektiv erfaßten Patienten (66% Perforationsperitonitis, 32% postoperative Peritonitis, 2% unklare Peritonitis) bestand bei 300 in der geschlossenen Behandlung mit Drainage, bei 138 in der programmierten Reintervention/Lavage. 64 Patienten (14,4%) verstarben, davon 34 an der Sepsis, 29 aus anderer Ursache. In der univariaten Analyse ergaben sich unterschiedliche Einflüsse der verschiedenen Parameter auf die Letalität. In der multivariaten Analyse (logistische Regression) erwies sich der präoperative Schockzustand als entscheidender unabhängiger Prognosefaktur, gefolgt mit deutlich abnehmender Wertigkeit von Begleiterkrankungen und präoperativen Sepsiszeichen. Ohne Einfluß waren die lokalen Befunde im Abdomen (auslösendes Organ, Ausdehnung der Infektion usw.). Der aus den Parametern einfach zu errechnende MPI zeigt eine enge Korrelation zwischen Punktescore und Letalität. Bei dem kritischen Index von 26 Punkten war die Spezifität 88%, die Sensitivität 78% und die Richtigkeit 78%. Der MPI eignet sich somit gut zur Definition und Klassifikation eines Krankenguts mit Peritonitis. Genauere Aussagen in Therapiestudien werden dadurch möglich.
    Notes: Abstract In order to evaluate the prognostic value of simple clinical parameters and the Mannheim PeritonitisIndex (MPI) 438 patients with abdominal infection entered a prospective study. 300 of them were managed by closed treatment with drainage, 138 by open treatment with planned relaparotomy. 63 patients (14.4%) died, 34 of them due to sepsis, 29 due to another cause. Stepwise logistic regression analysis showed only preoperative shock, concomitant disease and sepsis to be significant and independent factors leading to death. MPI had a strong correlation to mortality. Statistical validation showed a sensitivity of 88 % and a specifity of 78 % at the critical score of 26 points. The MPI is an easily documentated prognostic index for peritonitis with high accuracy in individual prognosis.
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  • 58
    ISSN: 1435-2451
    Keywords: Intra-abdominal lymphangioma ; Mesenteric cysts ; Abdominal symptoms
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Intraabdominelle Lymphangiome und Mesenterialzysten sind benigne zystische Tumoren, die, obwohl sie selten vorkommen, in der Differential-diagnose abdomineller Beschwerden berücksichtigt werden müssen. Vor allem aufgrund ihres unterschiedlichen biologischen Wachstumsverhaltens ist es wichtig, beide Läsionen voneinander abzugrenzen. In unserer Chirurgischen Klinik wurden zwischen 1979 und 1993 4 Patienten mit intraabdominellen zystischen Lymphangiomen und 2 Patienten mit Mesenterialzysten operiert. Von diesen 6 Patienten waren 5 klinisch auffällig. Die Symptomatik reichte von unspezifischen Abdominalbeschwerden bis zum akuten Abdomen. Die endgültige Diagnose konnte bei allen Patienten erst nach der Laparotomie und feingeweblicher Untersuchung der exzidierten Zysten gestellt werden.
    Notes: Abstract Although intra-abdominal lymphangioma and mesenteric cysts are rare benign tumours, they have to be considerated in the differential diagnosis of abdominal pain. Differentiation of these lesions is important, because lymphangiomas may follow a proliferative and invasive course. From 1979 to 1993 four patients with intra-abdominal cystic lymphangiomas and two with mesenteric cysts underwent operations in our surgical department. Five of these six patients had abdominal symptoms, ranging from unspecific abdominal pain to acute clinical abdomen. In all cases surgical enucleation or resection and histological classification were necessary before final diagnosis was possible.
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  • 59
    Electronic Resource
    Springer
    Langenbeck's archives of surgery 379 (1994), S. 193-194 
    ISSN: 1435-2451
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 60
    ISSN: 1435-2451
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 61
    ISSN: 1435-2451
    Keywords: Defecation disorder ; Pressure ratio ; EMG ; Puborectal muscle ; External anal sphincter muscle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In einer prospektiven elektromyographischen und manometrischen Studie wurde die Aktivität des M. sphincter ani externus und M. puborectalis bei Ruhe, Kontraktion und Pressen bei 23 Frauen (Durchschnittsalter 52 Jahre) mit obstruktiven Defäkationsstörungen untersucht. Als Kontrollgruppe dienten 22 gesunde Frauen mit einem durchschnittlichen Alter von 53 Jahren. In erster Linie sollte überprüft werden, wie die beiden Muskeln sich bei einer simulierten Defäkation (maximales Pressen) funktionell verhalten, und wie die Druckverhältnisse sich im Rektum und Analkanal dabei ändern. Ruhe-, Kontraktions- und Preßdruck (Rektum und Analkanal) zeigten zwischen den beiden Gruppen keine signifikanten Unterschiede. Puborectalis und Externus zeigten weitgehend sowohl in der Patienten- als auch in der Kontrollgruppe ein identisches Verhalten. Bis auf die Kontraktionsamplitude des M. puborectalis konnte man keine weitere statistischen Unterschiede zwischen den beiden Gruppen nachweisen. Beim Versuch, die veränderte Aktivität als Anismusindex zu erfassen, konnte eine solche Veränderung weder für den M. sphincter ani externus noch für den M. puborectalis objektiviert werden. Daraus folgern wir, daß eine elektromyographisch nachgewiesene Aktivitätszunahme der willkürlichen Beckenbodenmuskulatur während der Defäkation weniger eine pathologische Situation, sondern vielmehr einen Funktionszustand repräsentiert.
    Notes: Abstract In a prospective electromyographic and manometric study on 23 women (average age 52 years) with obstructive defecation disorder the activity of the external anal sphincter muscle and the puborectal muscle was investigated at rest and during contraction and straining. The control group consisted of 22 healthy women with an average age of 53 years. The main aim of the study was to investigate the functioning of the two muscles during simulated defecation (maximum strain) and to examine any changes in the pressure ratio in the rectum and the anal canal during this stimulation. There were no significant differences in the resting pressure, the contraction pressure and the straining pressure (in the rectum and the anal canal) between the two groups. The functioning of the puborectal muscle and the external anal sphincter muscle was largely the same in both the study group and the control group. No statistically significant differences were found between the two groups except in the amplitude of contraction. When we tried to list the change in the activity of the muscle as an index of anism, we were not able to objectify such a change for either the external anal sphincter muscle or the puborectal muscle. We there