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The widening gap between supply and demand for renal transplantation has prompted many centers to use donors after cardiac death. Some of these donors exhibit signs of acute renal failure (ARF) prior to cardiac arrest. Concern has been expressed about poor quality of graft function from such donors. In response to this perception, we reviewed 49 single renal transplant recipients from category III donors after cardiac death between 1998 and 2005, at our center. All kidneys but one had hypothermic machine perfusion and viability testing prior to transplantation. According to the RIFLE criteria, nine recipients had kidneys from donors with "low severity pre-arrest ARF". The remainder of the recipients were used as control group. There was no statistical significant difference in delayed graft function and rejection rates between these two groups. Recipients GFR at 12 months was 44.4 +/- 17.1 and 45.2 +/- 14.7 (mL/min/1.73m(2)) from donors with ARF and without ARF, respectively (p = 0.96). In conclusion, low severity ARF in kidneys from controlled after cardiac death donors can be a reversible condition after transplantation. Short-term results are comparable to the kidneys from same category donors without renal failure, providing that some form of viability assessment is implemented prior to transplantation.

Intraarterial cooling (IAC) of non-heart-beating donors (NHBD) for renal donation requires a cheap, low-viscosity solution. HTK contains a high hydrogen ion buffer level that theoretically should reduce the observable acidosis associated with ongoing anaerobic metabolism. A retrospective comparison of all retrieved NHBD kidneys as well as of viability on the Organ Recovery Systems Lifeporter machine perfusion circuit was performed with respect to the preservation solution HTK or Marshall's HOC. Forty-two NHBD kidneys (19 HTK and 23 HOC) were machine perfused between February 2004 and May 2005. Most of the HTK kidneys were obtained from uncontrolled donors (12 vs 5; Fisher exact test, P = .01). As a consequence, the glutathione-s-transferase viability assay (411 vs 292 IU/L, P = .12) and the lactate concentrations (2.33 vs 1.94 mmol/L, P = .13) were higher among the HTK cohort. There was evidence of greater buffering capacity in HTK, since the lactate:hydrogen ion ratios were consistently lower during the first 2 perfusion hours (1 hour P = .03, 2 hour P = .02). A linear regression analysis confirmed that this was related to the IAC solution (ANCOVA, P < .001). All controlled donor kidneys passed viability testing and were transplanted. In contrast, 83% (10/12) of the uncontrolled donor kidneys preserved with HTK passed the viability test and were transplanted, compared with only 20% (1/5) of the HOC-treated comparators (Fisher exact test, P = .03). It may be concluded that the postulated advantages of improved pH buffering with HTK appear to have clinical relevance.

Kidneys transplanted from non-heart-beating donors (NHBDs) have been exposed to varying degrees of ischemic damage after death. Category III donors have invariably been managed, treated, and investigated in a hospital setting prior to arrest and death. Some therefore exhibit evidence of renal dysfunction and even acute renal failure (ARF) before death. Many surgeons would regard a NHBD with pre-arrest evidence of ARF as too marginal for renal transplantation. This retrospective study examines five Maastricht category III NHBD donors with evidence of pre-arrest ARF. We compare 3- and 12-month GFR outcome data from the nine resulting transplants with 40 category III NHBD transplants with normal pre-arrest renal function. The mean GFR at 3 months was 45.4 and 43.8 for the ARF and normal group, respectively. At 12 months the GFR was 42.2 and 44.7 in the ARF and normal groups, respectively. Thus evidence of ARF pre-arrest does not preclude successful category III NHBD renal transplantation.

The shortage of donor kidneys for renal transplantation is becoming more severe as the gap between the number of patients waiting for renal transplantation and the number of cadaveric organs available continues to widen. Therefore, many centres have started using non-heart-beating (NHB) donors. There was no clear plan for maximal duration of agonal period in Maastricht category NHB donors after withdrawal of treatment in Newcastle. This withdrawal has been audited in retrospect. Our current wait time is now a maximum of 5 hours; however, previously there have been some considerably longer periods. Concern has always been expressed about poor quality with protracted periods. Nonuse in this review of 58 kidneys can be expressed against time: 0 to 2 hours 13%, 2 to 5 hours 33%, and >5 hours 45%. Therefore, though the nonuse rate was significantly different between 0 to 2 hours and >5 hours (P < .05, chi-square), there were 16 transplants performed with kidneys >2 hours and 12 transplanted >5 hours. In conclusion, although good usable kidneys can still be used with protracted withdrawal, there are considerable logistical difficulties with our 5-hour cut-off, which means that one third of potential kidneys will not be utilized.

Kidneys transplanted from non-heart-beating donors (NHBD) are generally regarded as marginal or extended criteria grafts due to the associated period of warm ischemia. The most prolonged periods occurring in the category II (uncontrolled) donor. This potential for injury can adversely affect the glomular filtration rate (GFR), which in severe cases results in primary nonfunction. Viability testing can identify a group of kidneys that, although unsuitable for solitary transplantation, may be considered for dual transplant. This retrospective study examined a series of 11 dual renal transplants, comparing 3- and 12-month GFR outcome data with 81 single NHBD transplants. The mean GFR at 3 months in the dual group was 47.6 and at 12 months was 48.6. In the single group the GFR at 3 months was 40.6 and at 12 months was 41.9. Thus using viability testing to identify NHBD kidneys suitable for dual transplant appears reliable and predictable.

Uncontrolled non-heart-beating donors offer the opportunity to significantly expand the potential pool of kidney donors but are associated with a variable duration of cardiopulmonary resuscitation (CPR), where cardiac output is only 30% to 40% of normal. We were concerned that prolonged CPR would adversely affect the function of transplanted kidneys. In our series of 46 uncontrolled donors the mean duration of CPR was 60 minutes, which also represents a realistic cutoff point for CPR duration. Taking a cutoff point of 60 minutes, we found no differences in kidney discard rates following viability assessment, primary nonfunction rate, or duration of delayed graft function. We therefore conclude that if formal viability assessment is performed, kidneys may be retrieved from uncontrolled non-heart-beating donors irrespective of duration of CPR.

Comparison of reperfusion injury in kidneys transplanted from LD, HBD or NHBD donors is presented in the paper. Central venous blood samples (taken during perioperative period) was assessed for free radicals, total antioxidant activity and various markers of tissue injury. There was demonstrable ischemia reperfusion injury occurring at the time of revascularization, which was particularly notable in kidneys transplanted from NHBD donors.

Purpose: Ischemia-reperfusion injury is gaining importance in transplantation as being responsible for allograft dysfunction. Ischemia occurs during kidney procurement, which is shortest in LDs, and prolonged in cadaveric HBDs and NHBDs. Materials and Methods: Renal transplants from 17 LDs, 15 HBDs and 19 NHBDs were assessed during reperfusion for biochemical markers of ischemia-reperfusion injury and assessed clinically. Central venous blood sampling was assayed for free radicals using electron spin resonance and tissue injury biomarkers, namely lactate dehydrogenase, fatty acid binding protein, alanine aminopeptidase, lactate and total antioxidants. Results: The return to stable renal function was more rapid in LD renal transplants, while recovery continued from 3 months after hospital discharge in NHBD renal transplants. Injury markers, such as lactate dehydrogenase, fatty acid binding protein, alanine aminopeptidase and lactate, were raised at the time of reperfusion, especially in NHBD renal transplants. Free radical release measured by electron spin resonance showed 2 phase release, that is early (0 to 10-minute) and late (20 to 40-minute) release. In NHBD, HBD and LD renal transplants the index of free radical release in the early phase was 1.43, 1.36 and 1.20, and in the late phase it was 1.43, 1.38 and 0.97, respectively (each ANOVA p <0.05). Conclusions: NHBD renal transplants were accompanied by a greater release of free radicals at reperfusion (NHBD > HBD > LD), which was associated with an increase in tissue injury markers at reperfusion. This was reflected in a slower return to stable renal function in NHBD compared to HBD and LD renal transplants. [Copyright &y& Elsevier]