Abstract
Abstract
Introduction:
Laparoscopic nephrectomy is an accepted alternative to open nephrectomy. We analyzed our first 80 procedures of laparoscopic nephrectomy to evaluate the effect of experience and configuration of service on operative times.
Materials and Methods:
A retrospective review of 80 consecutive children who underwent retroperitoneal laparoscopic nephrectomy or heminephrectomy during an 11-year period from 1997 at Christchurch Hospital (Christchurch, New Zealand) was conducted. Operative times, in relation to the experience of the surgeon for this procedure, were analyzed.
Results:
Four surgeons, assisted by an annually rotating trainee registrar, performed the procedure in 26 girls and 54 boys (range, 8 months to 15 years). Operating times ranged from 38 to 225 minutes (mean, 104). The average operative time fell from 105 to 90 minutes. One surgeon performed 40% of the procedures and assisted with a further 55%. The operative times for all surgeons showed a tendency to reduce, but this was not marked.
Conclusions:
Most procedures were performed by two surgeons working together, although one surgeon was involved in the majority of cases. The lead surgeon is often assisted by a fellow consultant colleague. Operative times were influenced by experience, but not markedly so. The shorter operative times and minimal “learning curve,” compared with other reported series, may, in part, be due to the involvement of two surgeons experienced in laparoscopy for the majority of cases.
Introduction
Materials and Methods
A retrospective review was undertaken of all children who underwent laparoscopic nephrectomy or heminephrectomy during an 11-year period. Demographic data and information on operative times and surgeon experience were collected. Operative times were measured from the time the surgeons commenced positioning the patient to when the sterile drapes were removed at the completion of surgery. Trends in operative times, according to surgeon and experience, were analyzed. Complications were noted, but this study was not able to determine whether experience influenced the complication rate.
Operative technique
The procedure is performed under general anesthesia with the patient prone. The outline of the spine, lateral border of the erecter spinae muscle, 12th rib, and iliac crest are marked. Three 5-mm ports are placed halfway between the 12th rib and iliac crest. The first port is placed at the lateral edge of the erector spinae muscle, using an initial incision, followed by blunt dissection, with artery forceps through the lumbodorsal fascia. A balloon is fashioned by tying the finger of a surgical glove to a No. 8 feeding tube. The balloon is placed in the space created beneath the lumbodorsal fascia and inflated with air, according to the age and size of the patient, varying from 180 to 600 mL. The balloon is deflated and withdrawn. A Hasson 5-mm trocar is inserted into the cavity created, which is maintained with insufflation with carbon dioxide at a pressure of 10 mm Hg. A 30-degree 5-mm scope is used. The two working 5-mm ports are inserted under direct vision: one lateral and one medial to the original port.
The perinephric fat is stripped off the kidney, and the loose lateral attachments of the kidney are separated by blunt dissection or divided with diathermy or a Harmonic scalpel. The renal vessels are identified and ligated with endoligaclips. The ureter is ligated as low as possible and divided. The renal moiety is removed through the lateral port site, which may require an extension of the incision. All port sites are infiltrated with 0.25% marcain.
Results
Eighty retroperitoneal laparoscopic nephrectomies were performed in children between 8 months and 15 years (mean, 4) during the study period. These included 2 upper and one lower pole heminephrectomies. Laparoscopic nephrectomy was performed, on average, 7.4 times per year. Operative times ranged from 38 to 225 minutes. The mean operative time in 1997 was 104 minutes. This was observed to have been reduced to 90 minutes in 2007. The trend to reduction in operative time was seen for all surgeons but was not significant (Fig. 1).
Operating times versus consecutive cases.
One surgeon participated in 95% of all cases (lead surgeon in 40% and assistant in 55%). The experience of the other three surgeons and registrar varied from 11, 17, 8, and 12 cases and as assistant in 10, 5, 1, and 17 cases, respectively. Over the first 10 cases, there was no learning curve evident. The operating times for all four surgeons remained relatively unchanged over time and ranged from 72 to 139 minutes, with no significant correlation to increasing experience. The majority (64%) of cases had two consultants present. The operative times for all surgeons showed a tendency toward reduction, but this was not marked. Renal pathology influenced operative time: Grossly dilated kidneys incurred significantly longer operative times than did the removal of simple, small cystic kidneys (mean, 134 versus 54 minutes, respectively). The complication rate was 5.2%. These were individual cases of postoperative fever, port-site incisional hernia, urine leak (following inadequate clamping of the ureteric stump), and adhesive bowel obstruction following a major retroperitoneal breach during the procedure.
Discussion
The effect of the learning curve on the performance of laparoscopic nephrectomy is not widely reported in the literature, and most reports have involved adult patients utilizing a transperitoneal approach. Tse et al., in 1994, 1 reported operating times that ranged from 225 to 480 minutes in 16 adults via the transperitoneal approach. Several surgeons were involved, and despite the title of the report, there was little evidence of a learning curve. A review of 63 adults treated by eight surgeons 2 described shorter operating times (170–395 minutes) via a transperitoneal approach, but the researchers were unable to identify a learning curve. The retroperitoneal approach was first reported in a series in 1998 by Rassweiler et al. 3 They compared operative times of retro- versus transperitoneal approaches in 17 and 18 adult patients, respectively, and found no difference—both approaches had a mean operative time of 206 minutes. A more recent article by Ku et al. 4 of 20 children operated on by a single surgeon, using both trans- and retroperitoneal approaches, revealed a reduction in operative time after 10 cases, with operative times ranging from 125 to 181 minutes. Gundeti et al.'s review of their experience of 100 consectutive cases in comparing the transperitoneal with the retroperitoneal approach, reported a mean operating time for the retroperitoneal approach of 96 minutes. 5 Three other series reported mean operating times of 180 (14 patient series using the transperitoneal approach), 6 133 (range, 60–240 for 40 patients using the transperitoneal approach), 7 and 163 minutes (9 patients via the transperitoneal approach). 8 Our operative times ranged from 38 to 225 minutes, with the mean operative time decreasing from 104 minutes in 1997 to 90 minutes in 2007, which is significantly shorter than in other series. It is possible that the involvement of two surgeons familiar with laparoscopic techniques, in the majority of cases, had contributed to the shorter operative times. The lead surgeon was a consultant in 85% of cases, assisted by a fellow consultant colleague in 79% of cases. Our low complication rate may also be attributable to having two consultant surgeons involved, thus providing a high level of available skill.
Conclusions
Retroperitoneal laparoscopic nephrectomy in children is a safe alternative to the open procedure. Our data showed only a modest decrease in operative times during the period reviewed (from 105 to 90 minutes). The involvement of two surgeons with preexisting laparoscopic skills may have obscured any learning-curve effect.
Footnotes
Disclosure Statement
No competing financial interests exist.