Organ bath in detecting the effect of one-hour warm ischemia on pulmonic arteries and bronchi from non-heart-beating donor lungs

Background Non-heart-beating donor lung has been a promising source of lung transplantation. Many studies on non-heart-beating donor lungs are based on animal lung transplantation. In this study, we assessed by organ bath the effect of one-hour warm ischemia on the non-heart-beating donor lung in terms of the integrity of contractile and relaxant functions and tissue structures of pulmonic arteries and bronchi. Methods Sixteen Swedish pigs were randomly classified into two groups： heart-beating donor group and 1-hour warm ischemia non-heart-beating donor group. Pulmonic and bronchial rings were taken from the isolated left lungs of the pigs. The pulmonic rings were stimulated by U-46619 （5.7 mol/L） and acetylcholine （104 mmol/L） to assess the contractile abilities of smooth muscle and the endothelium-dependent relaxation response, respectively. As such, acetylcholine （10^-5 mmol/L） and natrium arachidonic acid （0.01%） were used to detect the contraction of bronchial smooth muscle and epithelium-dependent relaxation response. Meanwhile, the variances of precontraction tension of control groups were recorded to measure whether there was spontaneous relaxation during endothelium/epithelium-dependent relaxation course. Finally, papaverine solution （10.4 mmol/L） was used to detect the non-endothelium/epithelium-dependent relaxant abilities of pulmonic and bronchial smooth muscles. Results There was no significant difference in the tension values of precontraction of pulmonic rings （P 〉0.05）, endothelium-dependent relaxation （P 〉0.05）, precontraction of bronchial rings （P 〉0.05） and epithelium-dependent relaxation （P 〉0.05） between the heart-beating donor group and the 1-hour warm ischemia non-heart-beating donor group. And the pulmonic and bronchial rings of each subgroup B had no spontaneous relaxation. Finally, papaverine solution relaxed the smooth muscle of all the rings completely. Conclusions The results of this experiment suggest that the contractile and relaxant functions and tissue structures of pulmonic arteries and bronchi are not damaged after warm ischemia for 1 hour, and support the further study of non-heart-beating donor lung.

Can the rat donor liver tolerate prolonged warm ischemia?

The last two decades of the twentieth century have witnessed increasingly successful rates of liver transplantation. The number of liver transplantations has increased steadily while the number of organ donors has remained relatively constant. Thus a great disparity has developed between the demand and supply of donor organs and remains a major limiting factor for further expansion of liver transplantation. Although many procedures, such as split liver[1] , living-related transplantation[2] , and xenotransplantation[3], have been attempted clinically to overcome the shortage, it is hoped that livers harvested from non-heart-beating donors (NHBDs) would alleviatethe problem of organ shortage, which again becomes the focus of attention[4-9]. However, sensitivity of the liver to warm ischemia remains a major worry for use of theNHBDs. The aim of this animal study was to assess if murine liver could tolerate prolonged period of warm ischemia and to determine the optimum timing of intervention in the cadaver donor in order to preserve liver viability.

Donation after cardio-circulatory death liver transplantation

The renewed interest in donation after cardio-circulatory death (DCD) started in the 1990s following the limited success of the transplant community to expand the donation after brain-death (DBD) organ supply and following the request of potential DCD families. Since then, DCD organ procurement and transplantation activities have rapidly expanded, particularly for nonvital organs, like kidneys. In liver transplantation (LT), DCD donors are a valuable organ source that helps to decrease the mortality rate on the waiting lists and to increase the availability of organs for transplantation despite a higher risk of early graft dysfunction, more frequent vascular and ischemia-type biliary lesions, higher rates of re-listing and re-transplantation and lower graft survival, which are obviously due to theinevitable warm ischemia occurring during the declaration of death and organ retrieval process. Experimental strategies intervening in both donors and recipients at different phases of the transplantation process have focused on the attenuation of ischemia-reperfusion injury and already gained encouraging results, and some of them have found their way from pre-clinical success into clinical reality. The future of DCD-LT is promising. Concerted efforts should concentrate on the identification of suitable donors (probably Maastricht category Ⅲ DCD donors), better donor and recipient matching (high risk donors to low risk recipients), use of advanced organ preservation techniques (oxygenated hypothermic machine perfusion, normothermic machine perfusion, venous systemic oxygen persufflation), and pharmacological modulation (probably a multi-factorial biologic modulation strategy) so that DCD liver allografts could be safely utilized and attain equivalent results as DBD-LT.

Detection of Bronchial Function of NHBD Lung Following One-h Warm Ischemia by Organ Bath Model

This study investigated the feasibility and effects of organ bath to be used for detection of bronchial function of non-heart-beating donor （NHBD） lung after 1-h warm ischemia. Sixteen Swedish pigs were divided into two groups randomly： heart-beating donor （HBD） group and NHBD with 1-h warm ischemia （NHBD-1 h） group. The bronchial rings whose lengths and inner diameters were both 1.5 mm were obtained from isolated left lungs of all the pigs. Acetylcholine, arachidonic acid natrium and papaverine were used to test and compare the contractile and relaxant function of bron- chial smooth muscles and epithelium-dependent relaxation （EpiDR） response between HBD and NHBD-1 h groups. The results showed that there was no significant difference in the values of bronchial precontraction between HBD and NHBD-1 h groups （5.18±0.07 vs 5.10±0.11 mN, P〉0.05）. No significant difference in the values of EpiDR responses between HBD and NHBD-1 h groups （1.26±0.05 vs 1.23±0.07 mN, P〉0.05） was observed either. During the process of EpiDR induction, the tings had no spontaneous relaxation in two groups. In addition, papaverine solution completely relaxed the bronchial smooth muscles of all bronchial tings. It was concluded that after warm ischemla for 1 h, the contractile and relaxant abilities of bronchial smooth muscles, and the epithelium-dependent adjustment both kept intact. Organ bath model could be a liable and scientific way to evaluate the bronchial function of NHBD lung.

Outcome of kidney transplantation between controlled cardiac death and brain death donors： a meta-analysis

Background Our goal was to evaluate the outcomes of kidney transplants from controlled cardiac death donors compared with brain death donors by conducting a meta-analysis of cohort studies.Methods The PubMed database and EMBASE were searched from January 1980 to July 2013 to identify studies that met pre-stated inclusion criteria.Reference lists of retrieved articles were also reviewed.Two authors independently extracted information on the designs of the studies,the characteristics of the study participants,and outcome assessments.Results Nine cohort studies involving 84 398 participants were included in this meta-analysis; 3 014 received kidneys from controlled cardiac death donors and 80 684 from brain death donors.Warm ischemia time was significantly longer for the controlled cardiac death donor group.The incidence of delayed graft function was 2.74 times （P 〈0.001） greater in the controlled cardiac death donor group.The results are in favor of the brain death donor group on short-term patient and graft survival while this difference became nonsignificant at mid-term and long term.Sensitivity analysis yielded similar results.No evidence of publication bias was observed.Conclusion This meta-analysis of retrospective cohort studies suggests that the outcome after controlled cardiac death donors is comparable with that obtained using kidneys from brain death donors.