Improved cardiac preservation by the addition of nitroglycerine to colloid-free University of Wisconsin solution (MUW).

BACKGROUND: This study examines whether the addition of nitroglycerine, a known coronary vasodilator and nitric oxide donor, to colloid-free University of Wisconsin solution will improve and extend cardiac preservation. METHODS: Rat hearts were flushed and stored in colloid-free University of Wisconsin solution with or without the addition of nitroglycerine for 12, 16 or 20 hours at 0 degrees C before heterotopic transplantation with an indwelling externalized intraventricular balloon-tipped catheter. One and 7 days after transplantation of the heart the catheter was connected to a pressure transducer and quantitative functional studies were performed. RESULTS: After 12 hours preservation with nitroglycerine in colloid-free University of Wisconsin solution 6/6 grafts continued to beat for 7 days compared to 3/6 without nitroglycerine. After 16 hours preservation the addition of nitroglycerine 5/7 hearts continued to beat for 7 days compared to 0/6 without nitroglycerine (p < .05). Only 1/6 hearts beat for 7 days after 20 hours preservation with nitroglycerine. On Days 1 and 7, the left ventricular developed pressure (LVDP), contractility (max dP/dt) and rate of relaxation (peak -dP/dt) of 12 hour preserved hearts was better (p < .05) when nitroglycerine was present. The function of hearts preserved with the addition of nitroglycerine was similar after 12 and 16 hours preservation. CONCLUSION: Nitroglycerine is a valuable additive to colloid-free University of Wisconsin solution, extending effective preservation of the rat heart to 16 hours and significantly improving left ventricular function after 12 and 16 hours preservation. The addition of nitroglycerine, however, did not extend preservation to 20 hours.

Modified technique of abdominal heart transplantation in the rat.

BACKGROUND: A rapid, reproducible screening model is essential for evaluation of novel preservation regimens. This study describes a modification of the abdominal rat heart transplantation model reducing anastomosis time and allowing quantitative assessment for 7 days. METHODS: Hearts, obtained from inbred Dark Agouti rats, were arrested and stored in cold colloid-free University of Wisconsin solution until transplantation. The Dark Agouti recipient underwent a left nephrectomy. The donor left common carotid artery was anastomosed to the recipient left renal artery with a "sleeve" anastomosis. The "cuffed" donor left pulmonary artery was inserted into the left renal vein. Study 1 examined continuing viability by daily palpation and morphologic study by examination of hematoxylin and eosin-stained sections on days 4 or 90. Study 2 examined quantitative assessment of cardiac function in the anesthetized recipient. The model was further modified by introducing an externalized, fluid-filled, balloon-tipped catheter into the left ventricle. RESULTS: The new technique allowed vascular anastomoses to be completed in 5 to 12 minutes, minimizing rewarming of the graft. Most (25 of 28) grafts beat for 90 days, and 80% of these showed normal structure. There was evidence of myocyte damage or arteriosclerosis in 5 of 25 at 90 days and in 4 of 17 at 4 days. Cardiac function parameters were similar in consecutive runs and did not change between days 1 and 7. CONCLUSION: This abdominal rat heart transplant model is quick and easy to perform, minimizes warm ischemia, and is suitable for both short- and long-term studies. Quantitative parameters, assessed by use of an in situ intraventricular balloon-tipped catheter, are reproducible and maintained for 7 days.

Implementation and learning of laproscopic donor nephrectomy by a non-transplant general surgeon with advanced laparoscopic skills.

INTRODUCTION: Traditionally performed by vascular surgeons or urologists, laparoscopic nephrectomy for live kidney donor transplantation has emerged as a new effective and safe technique. This study examines the implementation of this technique at our centre, as performed by a single general surgeon with expertise in advanced laparoscopic surgery. METHODS: Patient records for 78 live donor transplants performed between February 2002 and September 2008 were divided into two groups (with 39 patients each) analyzed. A variety of outcome variables were compared. The same individual surgeon performed all laparoscopic donor nephrectomy (LDN) procedures. RESULTS: A significant advantage was noted for LDN with respect to hospital stay (LDN 5.1 ± 1.1 days vs open donor nephrectomy [ODN] 6.4 ± 2.6 days, P=0.01) while ODN had a significant advantage with respect to operative time (LDN 241.1 ± 55.7 min vs ODN 152.0 ± 27.7 min, P<0.01). Within the LDN group, we noted a significant shortening in the operation time with each case as experience increased (see graph; P<0.01). The total postoperative complication rate was similar in both groups (LDN: 31% vs ODN: 44%, P=0.25). There was a trend towards more respiratory complications in ODN (ODN 11/39 [28%] vs LDN 5/39 [13%], P=0.09). CONCLUSION: While implementing a new procedure may result in longer operative times initially, these improve with time, and our data demonstrates no compromise in patient safety or outcomes. The LDN procedure proved to be a desirable alternative to ODN, with shorter hospital stay and improved operator skills with each case, and without significant compromise in allograft recovery.

Abdominal surgery in HIV/AIDS patients: indications, operative management, pathology and outcome.

Despite the increasing number of patients with the human immunodeficiency virus (HIV) infection, surgical experience with these patients remains limited. A retrospective review over a 9 year period (January 1985 to December 1993) was undertaken to determine the indications, operative management, pathologic findings and outcome of major abdominal surgery in these patients. A total of 51 procedures were performed in 45 patients; 30 patients had acquired immunodeficiency syndrome (AIDS) and 15 patients had asymptomatic HIV infection. Indications included gastrointestinal bleeding, complicated pancreatic pseudocysts, cholelithiasis, bowel obstruction, immune disorders, acute abdomens, elective laparotomy, colostomy formation, menorrhagia and Caesarean section. Pathologic findings directly related to the HIV infection were found in 81% of the AIDS patients and 35% of the asymptomatic HIV infected patients (P < 0.05). These included opportunistic infections, non-Hodgkin's lymphoma, Kaposi's sarcoma, immune disorders, lymphadenopathy and pancreatic pseudocysts. It was noted that AIDS patients had more complications than asymptomatic HIV infected patients with most complications related to chest problems and sepsis (61 vs 7%; P < 0.01). Emergency operations carried a higher complication rate than elective operations though this was not significant. The hospital mortality was 12%. On follow up, 13 of the 25 AIDS patients had died with the median survival of 7 months, while three of the 14 asymptomatic HIV infected patients had died with the median survival of 40 months. Of the remaining patients, the 12 AIDS patients had a median postoperative follow up of 7 months and the 11 asymptomatic HIV infected patients had a median postoperative follow up of 29.5 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Cytoprotective effect of glycine in cold stored canine renal tubules.

Reperfusion injury has been suggested to cause delayed graft function in renal transplantation. Methods to reduce reperfusion injury could lead to improved clinical renal transplantation. Glycine has been shown to suppress reperfusion injury in rabbit renal tubules and rat hepatocytes. In this study we have determined the effects of glycine on viability of isolated canine renal tubules. Renal tubules were cold stored at 4 degrees C under hypoxic conditions for up to 96 h in the UW solution and rewarmed to 37 degrees C for up to 2 h under oxygenated conditions to simulate reperfusion of an organ after cold static storage. Short-term storage (24 to 48 h) did not cause membrane injury (leakage of lactate dehydrogenase (LDH)) on rewarming. However, after 72 and 96 h cold storage reperfusion injury was evident and LDH leakage increased from about 25% to 59 +/- 3% and 71 +/- 2% at 72 and 96 h cold storage, respectively. The presence of 3 mM glycine in the reperfusion medium suppressed injury to cold-stored renal tubules. After cold storage for 72 and 96 h LDH leakage was reduced to control concentrations (31 +/- 3% and 29 +/- 1%, respectively). After cold storage for 72 h there was a reduction in ATP concentration in rewarmed renal tubules (3 nmol/mg protein at 48 h to 1.25 nmol/mg protein at 72 h). Also, there was a loss of mitochondrial functions including decreased stimulation of oxygen consumption by uncoupling of oxidative phosphorylation. Although glycine suppressed LDH leakage in renal tubules cold stored for 72 h it had no effect on the regeneration of ATP or mitochondrial functions, which remained depressed.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of solutions for preservation of the rabbit liver as tested by isolated perfusion.

The University of Wisconsin (UW) solution consists of a relatively complex mixture of agents. In this study we compared simpler preservation solutions, namely, histidine-tryptophan-ketoglutarate (HTK) and phosphate-buffered sucrose (PBS) with different compositions of UW solution in the isolated perfused rabbit liver model. Livers were stored cold for 24 and 48 h. After 24 h of preservation, the amount of bile produced in UW-preserved livers was significantly greater (P < 0.05) than that in HTK-preserved livers. Also, there was less LDH released into the perfusate in UW-preserved livers. There was more edema and lower K +/Na+rations in HTK-preserved livers than in UW-preserved livers (all data P < 0.05). After 48 h of preservation, the differences between livers preserved in UW or HTK solution were less noticeable than at 24 h and bile production was similar. LDH and AST release were greater in HTK-preserved livers than in UW livers, but these differences were not statistically significant. Preservation in PBS for 48 h was worse than in either UW or HTK solution. Substitution of polyethylene glycol (PEG) for hydroxyethyl starch (HES) in 48-h UW-preserved livers was not effective. We conclude that solutions simpler in composition than UW solution may be effective in kidney transplantation but do not appear suitable for successful liver preservation.

Long-term renal preservation and prevention of acute tubular necrosis by inhibition of arachidonate metabolism.

Experimental preservation time for pulsatile perfused dog kidneys was extended from three to five days by phospholipase A2 inhibition suggesting a pathomechanical role of products of phospholipolysis like thromboxane and leukotrienes in the development of acute graft failure after renal transplantation. We therefore investigated the effects of thromboxane- and leukotriene synthase inhibitors on postoperative renal transplant function in a model of pulsatile perfusion preservation as well as a cold storage preservation of dog kidneys. Addition of a thromboxane-synthase-inhibitor to the perfusion medium in pulsatile perfused kidneys and the combined application of a thromboxane-synthase-inhibitor and a leukotriene-synthase-inhibitor to the recipient of a cold storage preserved graft, improved graft function and reduced the incidence of delayed graft function as well as histopathological features of acute tubular necrosis.