Liver transplantation from non-heart-beating donors: current status and future prospects in an experimental model.

The widening gap between supply and demand for liver transplantation has prompted many transplant centers to use donors after cardiac death or non-heart-beating donors. These livers--contrary to "classical" brain-dead donors--are exposed to an unavoidable period of warm ischemia, jeopardizing graft function post-transplantation. In a newly developed preclinical model of liver transplantation, we studied--in a biologically unmodified environment--the exact tolerance of the liver to warm ischemia. Following the evidence that liver transplantation from non-heart-beating donors is feasible and safe, provided that warm and cold ischemia are kept short, a clinical programme of liver transplantation from non-heart-beating donors was successfully initiated in our and other Belgian centers. Recently, we demonstrated that the tolerance of such livers to warm ischemia could be substantially improved when some of the previously identified mechanisms leading to graft non-function were tackled by a multi-factorial pharmacological strategy. Meanwhile, cold storage has proven to be insufficient to optimally preserve organs from non-heart-beating donors. As an alternative, machine perfusion preservation was found to consistently improve outcome in kidney transplantation from non-heart-beating donors. Similarly, machine perfusion preservation could improve the preservation of livers, allowing to predict viability prior to transplantation and to ameliorate tolerance to warm ischemia. At present, the definition and development of optimal machine perfusion settings are under investigation at our institution.

Presumed and actual concentrations of reduced glutathione in preservation solutions.

Reduced glutathione (GSH), an important radical scavenger, has been added to various organ preservation solutions. Because GSH oxidizes into oxidized glutathione (GSSG) and only GSH has scavenging capacity, only GSH in the solution at the time of clinical use is relevant. The concentrations of GSH (GSH(conc)) and GSSG(conc) were determined in 2 static preservation solutions--University of Wisconsin (UW) and Celsior--and in 1 machine preservation solution--Kidney Preservation Solution 1 (KPS-1). We determined the half-life (T(1/2)) of freshly added GSH. The GSH(conc) in UW and KPS-1 was 0.006 ± 0.0018 mmol/L and 0.13 ± 0.30 mmol/L, respectively. The GSH(conc) in Celsior was 2.7 ± 0.17 mmol/L. The manufacturers of these solutions reported 3 mmol/L GSH. GSSG(conc) in UW, KPS-1, and Celsior was 1.58 ± 0.61 mmol/L, 1.13 ± 0.16 mmol/L, and 0.24 ± 0.01 mmol/L, respectively. T(1/2) of GSH in UW, KPS-1, and Celsior was 18 days, 86 days, and 83 days, respectively. The actual GSH(conc) in UW and KPS-1 at the time of clinical use was substantially lower than reported by the manufacturer, owing to the relatively short T(1/2) of GSH. For Celsior, the GSH(conc) was maintained. Therefore, addition of fresh GSH to UW and KPS-1 before clinical use is recommended.

Ethylene oxide allergy in patients on hemodialysis waiting for kidney transplantation: logistical nightmare or challenge? A case report.

Ethylene oxide (EO) is widely used as a sterilization gas for heat-sensitive devices. In EO-sensitized patients, this type of sterilization can cause rare but major allergic reactions such as hives, rash, asthma, or anaphylactic shock. Hemodialysis patients in particular are at risk of developing hypersensitivity to EO. In these patients, surgical interventions should be planned far in advance allowing a thorough EO-free preparation of all equipment needed for the surgery as well as for the pre-, peri-, and postoperative care. In contrast to elective surgery, kidney transplantation with allografts from deceased donors cannot be planned; exact timing is unpredictable. Furthermore, transplantation may take place years after patients have been put on the waiting list. Listing of patients sensitive for EO is therefore a logistical and medical challenge for all health care professionals involved in the patient's care (eg, surgeons, nephrologists, anesthetists, nurses, pharmacists, and sterilization specialists). This case report describes a patient with chronic kidney disease stage V who developed EO allergy during hemodialysis while waiting for a kidney transplantation. Diagnosis was made based on clinical signs and confirmed biochemically (including a positive radioallergosorbent test). Because the only treatment is avoidance of contact with EO-sterilized materials, a strict EO-free protocol was developed to allow an uneventful transplantation thereafter. Subsequently, 4 newly diagnosed EO-sensitive patients on the active kidney transplantation waiting list were diagnosed, and 1 of these patients has been transplanted successfully. EO allergy in patients on the waiting list for kidney transplantation is a unique challenging situation which, to the best of our knowledge, has not been reported yet for kidney transplantation. This report further highlights the logistical preparation of a renal transplantation, including anesthesiologic, surgical, and postoperative care.