Department of Surgery, Leicester General Hospital, Leicester, UK
Keywords: kidney transplantation; laparoscopy; live-; donor nephrectomy
Introduction
The demand for kidney transplantation continues to outstrip the supply, with the inevitable consequence that kidney transplant waiting lists lengthen each year. One of the potential solutions to this problem is to increase the use of live donors, a policy that has been particularly successful in Norway [1]. Although living kidney donation has many advantages, including the best graft survival results, these benefits carry a unique price in that an otherwise healthy individual must be exposed to all the risks of major surgery for the benefit of another person. A traditional open nephrectomy, whether performed through an extraperitoneal loin approach or a transperitoneal anterior approach, leaves a formidable wound. There is no doubt that this is one of the main disincentives to potential live donors who may express concerns about wound pain, poor cosmetic results and the need for a prolonged recovery period. The advent of laparoscopic live-donor nephrectomy has the potential to overcome many of these disincentives but there is a need to define the place of this new procedure before it becomes widely adopted.
Surgical technique
Laparoscopic nephrectomy was first performed for neoplasms and other pathologies in 1990 [2] and the techniques used were subsequently applied to live-donor nephrectomy. The first laparoscopic live-donor nephrectomy was performed by Dr Louis Kavoussi and Dr Lloyd Ratner at the Johns Hopkins Bayview Medical Center, Baltimore, USA on 8 February 1995 [3]. The 40-year-old donor gave his left kidney to his 41-year-old sister in an operation that lasted 3 h. The donor was discharged on the morning of the first post-operative day and returned to work, as a welder, 2 weeks later. Since then a number of centres in the USA and Europe have adopted the laparoscopic technique.
The operation is performed under general anaesthetic using a transperitoneal approach to the kidney. The donor is placed in a modified lateral decubitus position and a pneumoperitoneum is established using a Veress needle. In general, four laparoscopic ports are required: the video laparoscope is introduced through a 12-mm infra-umbilical port and two further 12-mm ports in the epigastrium and the left iliac fossa are used for the main dissecting instruments. A 5-mm port can be placed in the mid-axillary line in order to introduce an instrument for retraction of the colon or spleen. The operation begins with mobilization of the colon by incising the lateral peritoneal reflection from the splenic flexure to the pelvic inlet. The kidney is then identified by opening the overlying Gerota's fascia. The renal vein is dissected to display its adrenal and gonadal tributaries, which are divided between metal clips. The renal artery is then gently dissected free to demonstrate its origin from the aorta.
The ureter is mobilized with a generous amount of meso-ureteric tissue down to the level of the pelvic inlet. The ureter is clipped and divided at this point and then the remaining lateral, posterior and superior fascial attachments of the kidney are divided to leave the kidney attached only by its vascular pedicle. At this stage a 56 cm kidney retrieval incision is made either in the midline below the umbilicus or transversely just above the pubis. A purse-string suture is placed in the peritoneum, which is then incised to allow the introduction of a plastic kidney-retrieval bag without loss of the pneumoperitoneum. The renal artery is double-clipped flush with the aorta and divided distally with scissors and the renal vein is divided using an endovascular stapler placed proximal to the adrenal tributary. The kidney is then placed in the retrieval bag and removed through the midline or Pfannenstiel incision.
In general, the left kidney is removed as its vessels are longer than those on the right. The right renal vein may be particularly short and if it is necessary to perform a right donor nephrectomy, the safest access for kidney retrieval is through a 56 cm transverse incision in the right upper quadrant. The inferior vena cava can then be partially occluded with a vascular clamp so that the full length of the renal vein is taken. After removal, the kidney is immediately placed into ice and perfused with cold preservation fluid ready for transplantation into the recipient.
The technical success rate of laparoscopic live-donor nephrectomy is very high when the operation is performed by experienced surgeons. The Johns Hopkins University Hospital group has not needed to convert the laparoscopic procedure to an open laparotomy in a series of more than 130 cases [L. Ratner, personal communication, 1998]. The open conversion rate in the largest series (193 nephrectomies) reported in the literature so far was only 2.6% [7]. Nonetheless, the laparoscopic technique is technically difficult and this factor has probably limited its use so far. A recently described modification of technique is the use of hand-assisted laparoscopy in which the surgeon introduces one hand into the abdominal cavity through a sleeve device. This gives the surgeon an improved tactile sense, which may facilitate the identification and dissection of important structures such as the renal vessels and so reduce the total operating time [8].
The recent development of spiral CT angiography, which provides accurate 3-D reconstructions of the renal anatomy, has also proved to be an important aid for the laparoscopic surgeon. The definition of renal arterial anatomy by this new technique is at least as accurate as, and possibly even superior to, that of conventional intra-arterial digital subtraction angiography [9]. Moreover, spiral CT angiography provides detailed information about the venous and ureteric morphology. By carefully studying the computerized 3-D reconstructions, the surgeon can build up a pre-operative picture of the vascular anatomy in his mind's eye. This is invaluable in planning the operation and avoiding damage to the more difficult venous tributaries such as a short lumbar vein arising from the posterior aspect of the renal vein.
Comparisons of laparoscopic and conventional open nephrectomy
Although there have not been any randomized trials of open vs laparoscopic live-donor nephrectomy, a number of comparisons using historical controls are now available [47]. These studies suggest that blood loss, length of hospital stay, time to resumption of diet and post-operative analgesic requirements are all reduced when laparoscopic live-donor nephrectomy is compared to the traditional open operation. Moreover, return to normal activities such as driving, exercising, and caring for the home appears to be significantly quicker in patients undergoing a laparoscopic procedure. Laparoscopic donors felt able to return to work and actually did return to work sooner than donors undergoing open surgery. To give some typical figures, patients undergoing laparoscopic nephrectomy started driving and caring for the home after 2 weeks, resumed exercise and felt ready for work after 3 weeks, and returned to work 46 weeks after surgery. These recuperation times are between one-third and two-thirds shorter than the equivalent times for traditional open nephrectomy. The laparoscopic operation produces particularly good cosmetic results, especially if a Pfannenstiel incision is used for kidney retrieval. The hope is that, in removing some of the disincentives to donor nephrectomy, the laparoscopic approach will increase the transplant rate. This has certainly proved to be the case in Baltimore where the live-donor transplant rate has increased by more than 100% since the introduction of the laparoscopic procedure [L. Ratner, personal communication, 1998].
The great concern with laparoscopic live-donor nephrectomy is that the procedure may damage the transplant kidney and so transfer morbidity from the donor to the recipient. Renal warm ischaemic times of approximately 5 min during laparoscopic nephrectomy are of some concern but are likely to prove to be acceptable as the available evidence suggests that significant renal injury only occurs when warm ischaemia is prolonged [10]. The delayed graft function rates reported for transplants performed after laparoscopic nephrectomy range from 0 to 6.2% [4,6,7] and this would not appear to be significantly different from the reported rates following open live-donor nephrectomy [7,11]. The available graft survival data is relatively limited but suggests that laparoscopic and open nephrectomy are equally good with 12 year graft survival figures in the region of 9698% [47]. Despite this, a recent report has introduced a note of caution by describing a ureteric complication rate of 7.7% in recipients of transplants from laparoscopic donors compared to only 0.6% in transplant recipients where the kidney was removed at open operation [7]. The authors of this report did, however, find that the ureteral complication rate fell to zero in the laparoscopic group after a modification of their dissection technique to make sure that sufficient peri-ureteral tissues were mobilized.
Prospects
Enthusiasm for the use of laparoscopic live-donor nephrectomy is increasing around the world, but the introduction of this procedure cannot be supported purely by audit data and comparison with historical groups. Laparoscopic donor nephrectomy has been shown to be technically feasible and as with other types of minimal access surgery it is not surprising that there are advantages in terms of less pain, earlier mobilization, shorter hospital stay, earlier return to work, and improved long-term cosmetic results. Although the early results have been good, there is a need for much more data relating to the outcome of the recipient transplant operation after laparoscopic nephrectomy. It is timely, therefore, to consider performing a carefully designed randomized clinical trial which examines the safety, efficacy and cost of the laparoscopic and open operations.
Notes
Correspondence and offprint requests to: M. L. Nicholson, Department of Surgery, Leicester General Hospital, Leicester LE5 4PW, UK.
References