Clinical use of the Bretschneider HTK cardioplegic solution for in situ protection of the kidney

The first clinical use of Bretschneider's HTK-solution for in-situ-protection of the kidney in mild hypothermia is reported. By means of this protective method renal surgery can be performed in a bloodless field without permanent loss of renal function. After initial protective perfusion of the kidney no repeated perfusions or additional surface cooling must be done. There are no systemic side effects when the HTK-solution is applied appropriately.     

Morphological investigation of the porcine liver directly following preservation with Euro-Collins,University of Wisconsin and Bretschneider's HTK solution

Zusammenfassung Zur Klärung der Frage, ob unter der Anwendung verschiedener Verfahren zur Leberkonservierung strukturell nachweisbare perfusionsbedingte Schäden auftreten können, wurden Lebern von Schweinen mit a) HTK-Lösung nach Bretschneider (Histidin-Tryptophan-Ketoglutarat), b) Euro-Collins-Lösung (EC), c) University of Wisconsin-Lösung (UW) entsprechend den Anweisungen des Herstellers perfundiert. Anschließend wurden alle Organe zusammen mit unprotelctionierten Lebern licht- und elektronenmikroskopisch unter Einschluß computergestutzter morphometrischer Analysen untersucht. Die Kontinuität der Sinusendothelzellen, die Weite des Disseschen Raumes sowie die Ultrastruktur der Hepatozyten wurden primär durch keines der protektiven Verfahren beeintrdchtigt. Beträchtliche Unterschiede wurden aber hinsichtlich der Ausspülung des Blutes festgestellt. Die mit der HTK-Lösung perfundierten lebern waren mit Abstand am besten von korpuskulären Blutbestandteilen befreit, gefolgt von EC-und UW-Lebern. Mittels eines computerunterstützten Morphometrieverfahrens konnten keine signifikanten Größenunterschiede zwischen den Hepatozyten der EC-, UW- and HTK-Gruppe festgestellt wurden. Lediglich die Hepatozyten der normothermen Kontrollebern waren um 10% größer als diejenigen in den mit den 3 protektiven Lösungen perfundierten Organen. Es ergaben sich unter keinem der drei Protektionsverfahren strukturelle Anhaltspunkte für einen Perfusionsschaden.Supported by the Deutsche Forschungsgemeinschaft, SFB 330 -Organprotektion     

Lowering the calcium concentration in St. Thomas' Hospital cardioplegic solution improves protection during hypothermic ischemia

The concentration of calcium (1.2 mmol/L) in clinical St. Thomas' Hospital cardioplegic solution was chosen several years ago after dose-response studies in the normothermic isolated heart. However, recent studies with creatine phosphate in St. Thomas' Hospital solution demonstrated that additional myocardial protection during hypothermia resulted principally from its calcium-lowering effect in the solution. The isolated working rat heart model was therefore used to establish the optimal calcium concentration in St. Thomas' Hospital solution during lengthy hypothermic ischemia (20 degrees C, 300 minutes). The calcium content of standard St. Thomas' Hospital solution was varied from 0.0 to 1.5 mmol/L in eight treatment groups (n = 6 for each group). During ischemia, hearts were exposed to multidose cardioplegia (3 minutes every 30 minutes). Postischemic recovery of function was expressed as a percentage of preischemic control values. Release of creatine kinase and the time to return of sinus rhythm during the reperfusion period were also measured. These dose-response studies during hypothermic ischemia revealed a broad range of acceptable calcium concentrations (0.3 to 0.9 mmol/L), which appear optimal in St. Thomas' Hospital solution at 0.6 mmol/L. This concentration improved the postischemic recovery of aortic flow from 22.0% +/- 5.9% with control St. Thomas' Hospital solution (calcium concentration 1.2 mmol/L) to 86.0% +/- 4.0% (p less than 0.001). Other indices of functional recovery showed similar dramatic results. Creatine kinase release was reduced 84% (p less than 0.01) in the optimal calcium group. Postischemic reperfusion arrhythmias were diminished with the loser calcium concentration, with a significant decrease in the time between initial reperfusion until the return of sinus rhythm. In contrast, acalcemic St. Thomas' Hospital solution precipitated the calcium paradox with massive enzyme release and no functional recovery. Unlike prior published calcium dose-response studies at normothermia, these results demonstrate that the optimal calcium concentration during clinically relevant hypothermic ischemia is considerably lower than that of normal serum ionized calcium (1.2 mmol/L) and appears ideal at 0.6 mmol/L to realize even greater cardioprotective and antiarrhythmic effects with St. Thomas' Hospital solution.     

Minimal amounts of hyaluronidase in HTK or UW solution substantially improve the recovery of preserved hearts

Abstract  Rat hearts were preserved by simple storage for 18 h at 0–1 °C and reperfused parabiotically with whole blood from a host rat. The preservation solutions used for flush perfusion and storage were the commercial solutions EuroCollins, HTK, or UW with or without adding 40 mg/l hyaluronidase or Euro-Flush-Glutathione (EFG) solution, especially designed for prolonged heart storage. All solutions were filtered (0.45 pm) before use. The functional recovery was measured using a latex balloon in the left ventricle for LVP, dp/dt, and isotonic stroke volume. The metabolic recovery as well as the edema formation was determined from freeze-clamped myocardium at the end of reperfusion. In hearts preserved with hyaluronidase-containing solutions, the edema formation during reperfusion was reduced combined with an improvement in the coronary flow. Functional and metabolic recovery were improved in these hearts with significant increase in the stroke volume and ECP in all groups versus hearts preserved in the hyaluronidase-free basic solutions. The effectiveness of HTK preservation was significantly improved by hyaluronidase in all parameters measured in our study. The best functional and metabolic recovery was found in hearts preserved by HTK + H- or EFG-solu-tion. Thus, preservation solutions containing hyaluronidase, especially HTK + H and EFG, seem best suited for the prolonged storage preservation of the heart.     

Effect of Euro-Collins' or UW solution on the early graft function following cadaveric kidney transplantation

From November 1985 to March 1990, 55 cadaveric kidney transplants were performed under cyclosporine therapy. All kidneys were harvested from non-heart beating donors and cold stored after being flushed with EC solution (Group I, n = 27) or UW solution (Group II, n = 28). Warm ischemic time (min) in groups I and II were 7.1 +/- 3.3 and 6.9 +/- 2.3, respectively. Cold ischemic times (hr) in groups I and II were 6.9 +/- 2.4 and 8.4 +/- 2.8, respectively. Mean numbers of days for postoperative dialysis were 14.0 +/- 7.9 in group I and 7.9 +/- 5.8 in group II (p less than 0.05). One-month creatinine (mg/dl) was 2.9 +/- 2.8 in group I and 1.75 +/- 1.0 in group II (NS). One-month graft survivals (%) in groups I and II were 81.4% and 92.8%, respectively. In conclusion, UW solution has provided beneficial effect of preservation on ischemic damaged kidney and appears to be method of choice in non-heart beating cadaveric kidney transplantation.     

Myocardial high-energy phosphates, lactate and pyruvate during moderate or severe normothermic ischemia in rat hearts perfused with phosphoenolpyruvate and ATP in cardioplegic solution

Rat hearts were subjected to normothermic ischemia for 15 min (group I) or 30 min (group II). During the ischemic period the hearts were perfused twice with cardioplegic solution supplemented with 14.4 mM phosphoenolpyruvate (PEP) and/or 0.067 mM adenosine triphosphate (ATP), and at the end of ischemia they were freeze-clamped. The myocardial ATP content in group I fell to about 55% of normal values except in hearts supplemented with only PEP, which showed greater reduction. In group II the ATP fell to only about 5% of normal values, without significant differences between the subgroups Hearts supplemented with PEP alone or with combined PEP-ATP showed significantly higher levels of pyruvate than in hearts with only ATP supplementation or control hearts. The study thus demonstrated clear difference in ATP content between moderate and severe ischemic trauma. The high pyruvate levels after PEP supplementation indicate formation of pyruvate without concomitant lactate increase.     

Successful heart transplantation after 13 hours of donor heart ischemia with the use of HTK solution: a case report

INTRODUCTION: For heart transplantation (HTx), the recommended ischemic time (IT) for donor heart is not to exceed 6 hours. Though Dr Christiaan Barnard used a donor heart with IT of 16 hours, 50 minutes with a portable hypothermic perfusion system in 1981, the recorded IT of donor hearts reported recently is 8 hours, with no adverse effects. CASE REPORT: The patient, a 14-year-old boy of blood type O, was diagnosed with cardiomyopathy at age 12. In early September 2003, the patient was recommended for HTx. His condition deteriorated 18 days later with low CO, elevated pulmonary vascular resistance, and frequent ventricular tachycardia, further complicated by pneumonia and multiorganism infections, which were contraindications for HTx. On September 22, 2003, a donor heart of blood type O was available 370 km away. Another patient of blood type B with severe heart failure was matched for the HTx. During the intervening time, another donor heart of blood type B became available locally. We matched the type B donor heart to the type B recipient. Since the type O donor heart seemed to be wasted, we performed HTx for the boy. Though preserved for 12 hours in cold cardioplegia, the donor heart was implanted with biatrial anastomosis that took 1 hour. The total IT of this donor heart was 13 hours. The recipient recovered and was discharged 3 months later. CONCLUSIONS: The IT of 13 hours for this donor heart is believed to be a world record. Our experience demonstrates that preservation time of donor heart may exceed 6 hours.     

Response of the hypertrophied left ventricle to global ischemia. Comparison of hyperkalemic cardioplegic solution with and without verapamil.

The hypertrophied left ventricle is at considerably greater risk for injury when subjected to global ischemia than is an otherwise normal heart. We evaluated the efficacy of verapamil, a calcium-channel blocking agent, as an adjunct to standard crystalloid cardioplegic solution in animals with left ventricular hypertrophy subjected to myocardial ischemia during cardiopulmonary bypass. Infracoronary aortic stenosis was produced in 15 mongrel puppies by plication of the noncoronary cusp of the aortic valve. Studies were conducted 3 to 4 months later. Left ventricular catheter-tip pressure transducers and major and minor axis ultrasonic dimension crystals were inserted, and the animals were then supported by cardiopulmonary bypass with 30 minutes of normothermic ischemia. Animals were randomized to receive either standard hyperkalemic crystalloid cardioplegic solution (n = 8) or the same solution with verapamil, 0.1 mg/kg (n = 7). After the 30 minutes of ischemia, the animals were supported on cardiopulmonary bypass for an additional 30 minutes and then separated from bypass. They were then studied for another 2 hours by measurement of myocardial adenosine triphosphate content, myocardial blood flow, systolic function with use of the end-systolic pressure/volume ratio, and compliance with use of the natural strain coefficient of the minor axis at 15 mm Hg end-diastolic pressure. There was a better recovery of systolic function in the animals treated with verapamil (89.2% versus 63.3%). The compliance as measured with use of the minor axis natural strain coefficient returned essentially to baseline in the group of animals treated with verapamil (0.236 +/- 0.038 before ischemia and 0.254 +/- 0.043 2 hours after ischemia), but it fell markedly in the control animals (0.219 +/- 0.027 before ischemia and 0.153 +/- 0.016 2 hours after ischemia). Myocardial adenosine triphosphate levels were not significantly different at any time during the study. Likewise, myocardial blood flow was not significantly different between groups. We conclude that the addition of verapamil to hyperkalemic cardioplegic solution improves recovery of both systolic and diastolic function after global ischemia in dogs with left ventricular hypertrophy resulting from aortic stenosis. The precise mechanism for this is unknown.     

Oxidant stress following renal ischemia: changes in the glutathione redox ratio

Pretreatment of animals with certain antioxidant enzymes and substances decreases renal damage following ischemia and reperfusion. The hypothesis that reoxygenation imposes an oxidant stress has been used to explain this. The present study has directly assessed oxidant stress under these conditions by measuring the glutathione redox ratio ([GSSG/(GSH + GSSG)] x 100) in freeze-clamped kidney. The glutathione peroxidase system plays a role in removing peroxides which result from oxidant stress, generating GSSG from GSH in the process. The selenium-dependent glutathione peroxidase can metabolize H2O2 and other hydroperoxides. A non-selenium-dependent glutathione peroxidase activity is present and can metabolize organic hydroperoxides, but it cannot metabolize H2O2. Under anesthesia, the left renal artery was occluded for 40 minutes and then reflow was allowed. Kidneys were freeze clamped before reflow and after 5, 10, and 15 minutes of reflow. The contralateral kidney was freeze clamped and used as a control. The control value for the glutathione redox ratio was 1.09 +/- 0.05. This fell during ischemia to 0.67 +/- 0.22 and increased significantly to 1.66 +/- 0.29 after five minutes of reperfusion. By 15 minutes it had returned to 1.09 +/- 0.22. Treatment of rats with diquat, which causes a severe oxidant stress, raised the glutathione redox ratio from 0.88 +/- 0.12 to 1.89 +/- 0.15. Thus, reperfusion was concluded to cause a large but transient oxidant stress. Selenium-deficient rats were used to examine the nature of the oxidant stress. Activity of the selenoenzyme glutathione peroxidase was depressed to 2% of control in the kidneys of these rats.(ABSTRACT TRUNCATED AT 250 WORDS)     

Preservation of renal function following partial or radical nephrectomy using 24-hour creatinine clearance

OBJECTIVE: To compare the effect on renal function of partial and radical nephrectomy using creatinine clearance measurements from 24-hr urine collection. METHODS: All patients with a solid enhancing renal mass suspicious for renal cell carcinoma, a normal contralateral kidney, and not dialysis dependent were enrolled in this prospective cohort study. Patients were treated with partial or radical nephrectomy by one urologist. Creatinine clearance (CrCl) measurements were prospectively obtained by 24-hr urine collection preoperatively, and at 3, 6, and 12 mo postoperatively. Mean change in creatinine clearance from baseline was compared at 3, 6, and 12 mo. Serum creatinine and Cockcroft-Gault calculations were also performed for comparison. Mixed model analysis incorporating patient and tumor characteristics and the procedure type was performed in SAS Version 9.1. RESULTS: Sixty-three consecutive patients were enrolled in this study. The partial nephrectomy (n=26) and radical nephrectomy (n=37) groups were similar with respect to age, sex, presence of hypertension, vascular disease, diabetes mellitus, and angiotensin converting enzyme inhibitor or receptor blocker use. The postoperative change in creatinine clearance was significantly less (p-value < 0.0001) in the partial nephrectomy group (-0.09mL/s, -6.1%) compared to the radical nephrectomy group (-0.56mL/s, -31.6%). Linear regression analysis showed intervention type (partial vs. radical nephrectomy) was the most significant predictor of change in creatinine clearance (p-value < 0.0001). CONCLUSIONS: There is significantly less deterioration in the overall renal function of patients who are treated with partial nephrectomy compared to radical nephrectomy. This highlights the importance of performing nephron-sparing surgery on appropriate patients.     

The use of a nondepolarizing cardioplegic solution for cardiac preservation has a beneficial effect on the left ventricular diastolic function

We have developed a nondepolarizing solution (NDS) that retards myocardial calcium accumulation during cardioplegia. This study compares 1) the membrane resting potential (Em) in Purkinje fibers during cardioplegia induced by NDS or University of Wisconsin solution (UW) at normothermia and hypothermia for 6 h, 2) left ventricular (LV) diastolic function of isolated canine hearts preserved with NDS or UW for 6- and 12 h in hypothermia to elucidate the relationship between diastolic function and myocyte physiology (n = 8, each group), and 3) the effect of Non-depolarizing solution (NDS) compared with Bretschneider's HTK solution on LV diastolic function in isolated rabbit hearts using the Langendorff model in normothermia (n = 10, each group). The membrane resting potential (Em) was as follows: NDS in normothermia, –71 mV (2 min), –65 mV (30 min), and –52 mV (60 min); NDS in hypothermia, –40 mV (1 h) and –32 mV (6 h), while UW in hypothermia 0 mV (6 h). Myocardial calcium accumulation during reperfusion in the NDS groups was minimal and significantly lower than in the UW groups after the 6- and 12 h preservations. Postreperfusion myocardial cyclic adenosin monophosphate (cAMP) and adenosin tri-phosphate (ATP) concentrations in the NDS groups were closer to normal than in the UW groups after the 6- and 12 h preservations. The postreperfusion myocardial Ca concentration correlated with the cAMP (r = –0.68, n = 25, P = 0003) and cyclic guanosine monophosphate (cGMP) concentrations (r = –0.69, n = 25, P = 0.003). The left ventricular end-diastolic pressure (LVEDP) after reperfusion correlated with myocardial ATP (r = –0.65, n = 25, P = 0.003) and Ca concentrations (r = –0.68, n = 25, P = 0005). However, the parameter indicating LV elasticity (max LV –dp/dt) correlated with neither the Ca or ATP concentration following reperfusion. NDS prevented stiffness (increased LVEDP) better than HTK during normethermic cardioplegia for 30 min. These results in vitro suggest that NDS prevents myocardial Ca accumulation, depletion of ATP and cAMP, and preserves LV diastolic function, particularly stiffness after reperfusion, for up to 12 h. Furthermore, the mycoardial Ca concentration is inversely correlated with the cAMP and cGMP concentrations. Received: 14 October 1999 Revised: 30 October 2000 Accepted: 21 December 2000     

Evaluation of decapsulation of the canine kidney on renal function following acute ischemia.

Previous reports have suggested that the ischemic kidney develops a compression syndrome due to intracapsular edema and that decapsulation may improve function. This report evaluates renal function in ischemic kidneys with and without decapsulation. Thirteen dogs underwent creation of a split urinary bladder and the formation of bilateral cystocutaneous fistulas for measurement of split renal function. After systemic heparinization the suprarenal aorta was crossclamped for $\text{1}\text{1}\text{2}$ hr. One kidney underwent removal of the anterior aspect of the capsule and the other intact kidney served as the control. The animals received 1000 ml/24 hr, 0.15 N NaCl solution IV postoperatively. Urine volume, osmolarity, creatinine, and sodium were quantitated during three consecutive 24-hr periods. Seventy-two hours following the ischemic injury, the dogs were reexplored. Renal interstitial pressures were measured and renal biopsies and an intravenous pyelogram performed prior to sacrifice. Significantly greater urine volume was produced by the decapsulated kidney (302 ± 35 ml/24 hr) than by the nondecapsulated kidney (173 ± 39 ml/24 hr). Urine sodium excretion/24 hr was consistently greater from the decapsulated kidney than from the intact kidney while urine osmolarity at 72 hr from the decapsulated kidney was 584 ± 76 and from the intact kidney was 325 ± 76 mosmole/liter (P < 0.05). Renal interstitial pressures were significantly greater in the intact kidney than in the decapsulated kidney. These data suggest that release of intercapsular compression can improve renal function in the ischemic canine kidney.