The Isolated Perfused Kidney of the Pig: New Model to Evaluate Shock Wave-Induced Lesions

Abstract

Little is known about the mechanisms and determining factors of shock wave-induced kidney trauma. After classification of the renal lesion in a canine model, we attempted to establish an ex vivo model using the isolated kidney of the pig perfused by Tyrode's solution under physiologic conditions. After shock wave application on the Modulith SL 20, vessel lesions were evaluated by microangiography to determine the size and frequency of dye extravasation in the different areas of the organ. Variation of the focus localization caused different patterns of lesions that characterized the pathway of the shock wave. In particular, constant petechial extravasation in the cortex was observed. The generator voltage correlated with the diameter and the frequency of the lesion area. The number of shock waves primarily affected the incidence of vessel rupture in the regions adjacent to the focal zone. Light microscopy revealed dose-dependent necrosis of tubular cells up to gap-like parenchymal defects. Even after application of the minimal shock wave doses, electron microscopy demonstrated vacuolization of tubular cells in the shock wave focus. Traumatic junctions between capillaries and the tubulur system can explain clinically observed macrohematuria without renal hematomas. With this model, it was possible to evaluate localization and dose dependence of shock wave-induced kidney trauma with high sensitivity and reproducibility. Further advantages of the model were easy availability and the fact that studies on living animals were not necessary. Therefore, standardization and comparison of different lithotripters becomes possible.

The Hemostatic Properties of Transurethral Plasmakinetic Resection of the Prostate: Comparison with Conventional Resectoscope in an ex vivo Study

“…The present ex vivo model enables bleeding to be monitored and measured, and allows a direct comparison of the hemostatic properties of different techniques. Because heparinized blood has little function in blood coagulation and we focused on the vessel-sealing effects produced by different devices, unlike Koehrmann et al [9] and Michel et al [10] , whose experiments were carried out strictly with the corresponding autologous blood of each pair of kidneys, we applied NS instead of heparinized blood to facilitate the experiments since they both effused from the ruptured vessels. Following one of the principles of electrosurgery, namely using the lowest appropriate power setting to achieve the desired effect, we adopted the modes and watt values recommended by the device producer (160 W in mode PK3 and 120 W in mode URO, respectively).…”

“…We modified an ex vivo model of isolated blood-perfused porcine kidney introduced by Koehrmann et al [9] and Michel et al [10] . Their experiments were carried out strictly with the corresponding autologous blood of each pair of kidneys.…”

Extracorporeal perfusion of isolated organs of large animals – Bridging the gap between in vitro and in vivo studies

“…Two different blood preparations were used and weight gain was reported to be under 20% (Waugh and Kubo, 1969). Use of Tyrode or barium sulfate (BaSO 4 ) solutions for perfusion were associated with well-preserved histological morphology in experiments in which shockwave-induced lesions were investigated (Köhrmann et al, 1994). Perfusion with cell free Tyrode solution was on a par with autologous blood preparations in terms of reperfusion injury but was inferior in preserving renal function (Höchel et al, 2003).…”

Resuscitation of warm ischaemia predamaged porcine kidneys by fibrinolytic preflush with streptokinase: reduction of animal experiments

“…This procedure simulates the situation of WI in the slaughterhouse where explantation of kidney is usually performed within 8-30 min after stunning of the animal. 8,9,14 After nephrectomy the renal artery, the vein and the ureter of the kidneys were cannulated. The organs of group A (control) and B (WI) were subsequently rinsed with 500 mL of room temperature (RT, 228C) isotonic NaCl solution (B Braun Melsungen AG, Melsungen, Germany), transferred on ice and infused with 250 mL 48C histidine-tryptophan-alpha-ketoglutarate (HTK, Custodiol; Koehler Chemie, Alsbach, Germany) solution.…”