Comparison of laparoscopic and mini incision open donor nephrectomy: single blind, randomised controlled clinical trial

Participants and methods

We recruited to our study living kidney donors at the university medical centres in Rotterdam and Nijmegen. Eligible donors were informed about the surgical approaches and invited to participate in the study. Screening of donors included preoperative examination by a nephrologist, renal ultrasonography, and magnetic resonance angiography or computed tomography-angiography to evaluate the arterial and venous anatomy of the kidneys. If both kidneys were suitable for transplantation the right kidney was preferred.6 Exclusion criteria were bilateral abnormalities of the renal arteries (origin stenosis), previous operations of the kidney or adrenal gland, radiological abnormalities necessitating a modified approach (for example, solid tumours requiring frozen sections), and the inability to read Dutch. Patients were not excluded because of age, multiple arteries, obesity, or previous abdominal surgery other than adrenal or renal surgery. The day before surgery the surgeon confirmed that the patient had given informed consent.

Randomisation

The surgeon telephoned the study coordinator after informed consent had been confirmed, who opened the next numbered sealed opaque envelope provided by the trial statistician. Randomisation was carried out according to a computer generated list using a hidden block size of four. Stratification was not by centre. Donors were randomised less than 12 hours before surgery. All healthcare professionals except the surgical team were unaware of the allocated procedure. At the end of the operation the abdomen of all donors was covered with a standard pattern of dressings stained with one or two drops of blood to simulate real wound dressings. In case of an emergency, a sealed envelope detailing the procedure was left in the patient's notes.

Anaesthesia and analgesia

Donors were prehydrated with intravenous crystalloids. Antithrombotic stockings were used routinely. After endotracheal intubation, anaesthesia was carried out according to a strict protocol for drugs, ventilation, and fluid regimens. One hour after the start of surgery the donors received 20 mg mannitol. Except for one donor who required endocarditis prophylaxis, no antibiotics were given. At the end of surgery donors received patient controlled analgesia using intravenous morphine. They were also offered two 500 mg paracetamol tablets four times daily until discharge. The device for patient controlled analgesia was removed when morphine had not been required for at least six hours.

Surgical procedures

The surgical procedures were carried out by one of four surgeons skilled in both techniques. The trial coordinator in each centre attended the operations to document blood loss, operation time, use of instruments, and complications. Complications were defined as events necessitating intraoperative or postoperative interventions or that prolonged hospital stay.

Both techniques were carried out as described previously,5 with the donor in a lateral decubitus position. Briefly, during laparoscopic nephrectomy the camera and three or four additional trocars were introduced under vision. After dissection of the kidney, ureter, and vascular structures, an endobag (Endo-catch; US Surgical, Norwalk, CT, USA) was introduced. The renal artery and vein were divided with linear stapling devices (Endo GIA; US Surgical), and the kidney was extracted through a pfannenstiel incision. The skin wounds were sutured intracutaneously

To enable mini incision open nephrectomy a horizontal skin incision 10-12 cm long was made anterior to the 11th rib. The fascia and muscles of the abdominal wall were split using a mechanical retractor (Omnitract surgical, St Paul, USA). Gerota's fascia was opened on the lateral side of the kidney. After dissection of the kidney the surgeon clamped, cut, and ligated the ureter, renal artery, and vein. The kidney was extracted. The fascias of the abdominal muscles were closed, the subcutaneous fascia was approximated, and the skin was sutured intracutaneously.

Postoperative data and quality of life

The donor determined timing of discharge on the basis of tolerance to a normal diet and ability to use stairs. We calculated postoperative hospital stay with and without correction for time spent in hospital as a result of non-medical reasons (lack of care at home). Donors were seen at the outpatient clinic at three weeks, three months, and one year postoperatively. They were asked to complete forms related to pain, nausea, body image, fatigue, and quality of life. Preoperatively and at days 1, 3, 7, and 14 the donors scored pain and nausea on a visual analogue scale from 0 (none) to 10 (severe).

Body image was assessed at one year postoperatively using the body image questionnaire,7 which consists of two scales: the body image scale, which assesses attitudes to bodily appearance and consists of five questions (score 5-20), and the cosmetic scale, which assesses degree of satisfaction with the appearance of the scar and consists of three questions (score 3-24). Higher scores on both scales indicate greater satisfaction.

To assess whether laparoscopic nephrectomy and open nephrectomy differentially affected health related quality of life and fatigue, we administered the SF-36 and the multidimensional fatigue inventory 20 (MFI-20) preoperatively and at 1, 3, 6, and 12 months postoperatively. The SF-36 includes one multi-item scale measuring each of eight health concepts: physical function, role limitations due to physical health problems, bodily pain, general health, vitality, social functioning, role limitations due to emotional problems, and mental health.8 Scores per dimension of the SF-36 ranged from 0 to 100, with higher scores indicating better quality of life. We considered a five point difference between laparoscopic nephrectomy and open nephrectomy on a dimension as minimally clinically relevant.8

We determined levels of fatigue using the MFI-20,9 which consists of 20 items divided into five scales: general fatigue, physical fatigue, reduced activity, reduced motivation, and mental fatigue. Scores per item ranged from 1 to 5: total score per scale ranged from 4 (no fatigue) to 20 (exhausted).

Recipients

Recipients were admitted to a surgical ward separated from that of the donor to minimise influence on the donor's recovery. Renal transplantation was carried out using the standard technique of preperitoneal placement in the iliac fossa. The immunosuppressive regimen included mycophenolate mofetil, tacrolimus, and prednisone. During the first year postoperatively we recorded survival rates of recipients and grafts, acute rejection rates (histologically proved), venous thrombosis, and ureteral complications as defined as the need for a percutaneous nephrostomy, ureter reconstructions, and renal function.

Statistical analysis

Fatigue and quality of life are closely related. However, fatigue as an outcome of the intervention might be more suitable for indicating the effect of a surgical approach than the quality of life test. The quality of life test may be influenced by other factors, such as satisfaction after donor nephrectomy. The primary outcome was therefore physical fatigue on the MFI-20 and the secondary outcome was physical function on the SF-36. Other secondary end points were postoperative hospital stay, pain, operating times, recipient graft function, and graft survival. Power calculations were based on physical fatigue. Fifty donors had to be included in each arm to establish a moderate significant difference of 0.6 standard deviations in physical fatigue with a power of 80% and an α of 0.05. We used the χ² test to compare categorical variables and the Mann-Whitney U test to compare continuous variables. Repeated measurement of analysis of covariance was used to compare repeated continuous variables. We adjusted repeated measures for baseline values, donor's sex, and age. Analyses were carried out using SPSS version 11.0. We analysed data according to the intention to treat principle. P values less than 0.05 (two sided) were considered statistically significant.

Surgery

The procedures were all carried out as planned without conversion to open or formal lumbotomy (table 2). In the laparoscopic group skin to skin time and warm ischaemia time were significantly longer and blood loss was less. Intraoperative complications occurred in six patients (12%) during laparoscopic nephrectomy, which were bleeding in three (total blood loss 400-860 ml), a serosal lesion of the colon, a bladder lesion, and a small capsular tear of the spleen. The lesions were recognised immediately and treated without conversion. Re-interventions were not indicated. The three (6%) complications during open nephrectomy involved bleeding (total blood loss 1000-1800 ml), which was controlled during surgery.

Postoperative outcomes

Laparoscopic nephrectomy resulted in faster recovery as reflected by earlier resumption of a normal diet, less need for intravenous morphine, and earlier discharge (table 2). During the first two weeks donors in the laparoscopic group experienced significantly less pain. Postoperative complications after laparoscopic nephrectomy were wound infections at the extraction site in two donors, which were treated with oral antibiotics, and a blood transfusion. Complications after open nephrectomy were a urinary tract infection, a minor pulmonary infiltrate (both not requiring antibiotics), and an infected retroperitoneal haematoma, for which the patient required readmission for intravenous antibiotics. Other complications, such as incisional hernias, did not occur. Donors in both groups had similar serum creatinine levels. Scores on the body image scale did not differ significantly between the groups.

Recipients

One recipient (laparoscopic nephrectomy) died on the first postoperative day due to myocardial infarction. Two others (one in each group) died in the first year due to progressive infections related to an immunocompromised status. One recipient's graft (open nephrectomy) did not survive due to vascular rejection (table 2). She currently undergoes haemodialysis. Renal vein thrombosis did not occur in either group. Three recipients had ureteral complications after open nephrectomy, including ureteral stenosis and leaking, leading to ureteral reconstructions. Serum creatinine levels in recipients of kidneys from donors in both groups decreased in parallel without any significant differences over time.

Quality of life and fatigue

Response ranged from 97% at one month to 89% at 12 months, with an equal distribution at all times between laparoscopic and open nephrectomy. At baseline donors in both groups had excellent health status.8 Scores on the domains role physical and bodily pain were comparable at all time points (table 3). All other dimensions differed over time in favour of laparoscopic nephrectomy. Figure 2 shows scores for physical function over time in both groups. Patients in the laparoscopic group had higher mean scores for physical function during follow-up, indicating better quality of life (difference 6.2 points, 95% confidence interval 2.0 to 10.3, P = 0.004). Similar patterns were found for the other dimensions (see bmj.com).

Fig 2

Physical function and physical fatigue (means with 95% confidence intervals) during follow-up of living kidney donors after laparoscopic nephrectomy or mini incision open donor nephrectomy. Numbers refer to donors evaluated at each time point

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Physical fatigue scores were significantly lower for donors in the laparoscopic group, indicating less physical fatigue (fig 2): difference during one year's follow-up (- 1.3, 95% confidence interval - 2.4 to - 0.1, P = 0.03). Other dimensions of fatigue did not differ between the groups over time (see bmj.com).