The prolongation of waiting times and the increasing disparity between organ demand and supply have resulted in a greater reliance on live kidney donors. Increased utilization of live donors represents the most immediately available way to augment organ supply. With the liberalization of donor acceptance criteria and the more aggressive encouragement of live donors, United Network for Organ Sharing (UNOS) reported that live donors outnumbered cadaveric donors in 2001 for the first time (1). However, it is important that live kidney donors and their prospective recipients are given an accurate portrayal of the risks, both short- and long-term, that donors will face. The changing trends in live kidney donation having resulted in the liberalization of donor acceptance criteria in some centers, and the introduction of new surgical techniques such as laparoscopic, hand-assisted laparoscopic and minimal incision open surgical approaches, make it is high time to take a fresh look at the risks associated with live kidney donation. Thus, Drs Matas, Bartlett, Leichtman and Delmonico should be commended for their efforts and the valuable new information that they provide (2).
Although a study based on a retrospective survey has inherent limitations, Matas et al. have collected data from 10 828 live donor nephrectomies that were performed at 234 centers. They have been able to demonstrate that the peri-operative mortality and morbidity are low. Previous series from the early 1990s demonstrated that live donor nephrectomy had a mortality of 0.03% (3). The current series has a 0.02% mortality, which is on the same order of magnitude as the annual rate of ∼ 0.015% for vehicular fatalities in the United States (4). Similarly, the incidence rates of peri-operative complications, re-operation, and re-admission are also low. Although some complications, such as the need for readmission due to gastrointestinal complaints or bleeding, occurred more frequently following a laparoscopic approach than an open approach, these comparisons should be taken with a grain of salt, since the criteria used to define a bleeding complication or what symptoms prompted readmission rather than outpatient management or delayed discharge are not defined, and likely represent a highly heterogeneous mixture. However, the two fatalities in the current series were both in patients undergoing laparoscopic donor nephrectomy and had occurred in centers that had performed fewer than 25 laparoscopic donor nephrectomies. Additionally, the unusual complication of rhabdomyolysis was also seen exclusively in the laparoscopic cohort.
Laparoscopic live donor nephrectomy was introduced clinically in 1995 (5), with the goal of decreasing the financial and logistical disincentives to live kidney donation. Multiple single center reports have demonstrated advantages in terms of decreased pain, shortened hospitalization, quicker recuperation and earlier return to work (5–7). The hand-assisted laparoscopic approach was devised in part to minimize the learning curve for surgeons with limited laparoscopic expertise. Patient demand coupled with competitive and financial pressures has caused many programs to adopt some form of the laparoscopic donor operation (8). The authors report that laparoscopic approaches accounted for 47% of live donor nephrectomies performed from January 1999 to July 2001. However, open conversion rates and whether or not differential acceptance criteria are applied for the laparoscopic vs. open techniques are not addressed. It is important that surgeons who begin performing this operation appreciate its technical difficulty. It is my opinion that, in rare instances, surgeons have attempted to perform this operation despite being ill-equipped, either because of insufficient laparoscopic skills, or because they did not learn the fine points of the operation from those who preceded them. However, the consequences of these premature efforts are unknown. Laparoscopic donor nephrectomy is now a mature operation, and the learning curve inherent in the development of any new procedure has been overcome. Yet, for any individual surgeon first learning the operation, a separate learning curve exists. And, although an institution may have considerable experience with the operation, some elements of the learning curve will need to be overcome anew with each new surgeon performing the operation. Although the authors have attempted to quantify the institutional experience with laparoscopic donor nephrectomy, they did not examine the number of cases of laparoscopic donor nephrectomy or the overall laparoscopic expertise of the individual surgeons performing this operation. Thus, no reliable conclusions can be drawn about the inherent safety of this operation vs. the impact of the learning curve on its safety.
In response to the introduction of laparoscopic live donor nephrectomy, some centers have championed alternative approaches to open donor nephrectomies, such as those performed through a minimal flank incision, a dorsal lumbotomy incision, or an anterior retroperitoneal approach. The authors do not provide any data on the frequency with which these alternative open approaches are performed, or whether or not these newer approaches have any impact on morbidity.
Although, Matas et al. have demonstrated that in general live kidney donation is very safe, it is incumbent upon us to improve donor safety. Thus the questions we must ask are: (i) How can both open and laparoscopic operations be improved, not only to shorten recuperation, but also to reduce the risk of complications or death? (ii) Is there something inherently unsafe about the laparoscopic donor operation (as some surgeons believe)? (iii) Has the learning curve been minimized both for the laparoscopic operation itself and for any individual surgeon? (iv) Does the surgeon performing this operation have sufficient skills and expertise? (v) How should surgeons be credentialed for live donor operations? To date, there are no standard recommendations for how an individual surgeon should be trained or what criteria are used to judge their competency in regard to either open or laparoscopic live donor nephrectomy. Currently, UNOS is formulating minimal experience criteria for surgeons at centers performing either open or laparoscopic live donor nephrectomies.
Concomitant with the development of new surgical techniques for donor nephrectomy has been a liberalization of donor acceptance criteria at many institutions. Obese, elderly, mildly hypertensive individuals or those with substantial family histories of diabetes and hypertension are frequently being utilized as live donors at many centers. The impact that these relaxed acceptance criteria will have on long-term donor health is unknown. Matas and colleagues also advocate a donor registry, and this laudable and important goal should be supported. Ideally, for the greatest scientific accuracy and statistical significance a mandatory rather than a voluntary registry is most desirable, but this is likely to be formidable task. One should not overlook the logistical difficulties in tracking healthy individuals, many of whom may be geographically remote from their transplant center, over long periods of time. Additionally, data collection and reporting of this sort are unlikely to be reimbursed activities, and can potentially put additional manpower and fiscal pressure on transplant centers already operating under tight financial constraints. Alternatively, a voluntary web-based registry where patients enter their data directly may be feasible, although only incomplete reporting could be expected. Thus, these issues will need to be addressed during the planning of such a registry.
In summary, Matas and colleagues have demonstrated that, despite a variety of changes in clinical practice, live donor nephrectomy is a very safe operation. However, there is certainly room for improvement in clinical outcomes. This may require the more rigorous training and credentialing of surgeons. Additionally, long-term data need to be obtained in a systematic fashion. Given the recent advances in live donor transplantation across the ABO barriers (9) and despite positive cross-matches (10) and the insufficient supply of cadaver donor organs, live kidney donation will continue to increase in prominence for the foreseeable future. Scientifically sound and compelling data pertaining to the safety and the benefits of live kidney donation are likely to be the best tool in the recruitment of live kidney donors. However, we must also continue to remove the remaining financial and logistical disincentives to live donation that many donors still encounter.