Transperitoneal versus retroperitoneal laparoscopic pyeloplasty in children: Randomized clinical trial

Laparoscopic pyeloplasty achieves good cosmetic and functional outcomes. Both transperitoneal and retroperitoneal approaches are used. No single study to date has compared the two approaches in a prospective randomized design.

We present a prospective randomized comparison between both approaches in children in a trial to define which technique is better with regard to multiple factors including operative time, hospital stay, recovery of bowel movement, analgesic requirement and complication rate.

In the period from June 2010 to September 2012, 38 children (25 boys and 13 girls) were operated laparoscopically. Children were randomized into Group I (19 children) operated by the transperitoneal approach, and Group II (19 children) operated by the retroperitoneal approach. Both groups were compared as regards to the operative time, anesthetic changes, and postoperative recovery. A minimum sample size required was calculated to be 19 for each arm based on previous studies of laparoscopic pyeloplasty, using a mean difference in operative time = 40 min, effect size = 0.95, an alpha of 0.05 and power 80% and an online sample size calculator. Statistical analysis was performed using SPSS software using the Fischer exact test, chi square test and Mann-Whitney U test. The operative time was the primary endpoint for comparison between both approaches.

Our series is the first in the literature that compares in a prospective randomized design the transperitoneal and retroperitoneal laparoscopic pyeloplasty in children. Shouma et al. is the only prospective randomized study to compare both techniques in adult pyeloplasty. They had a significantly shorter operative time in the transperitoneal group however, the author in the discussion mentioned that he was at the start of the learning curve for retroperitonoscopic pyeloplasty when he conducted his study, which affected the result of the operative time. Hence, as mentioned above, we stressed the importance of a single surgeon with adequate equal experience in both techniques. The recovery of the intestinal motility and start of oral feeding were significantly faster in the retroperitoneal group compared to the transperitoneal group. In our opinion this can be explained by the absence of intraperitoneal manipulations and urine leakage in the peritoneal space. In their series of retroperitoneal pyeloplasty, El Ghoneimi et al. reported feeding after a mean of 1.4 days, however, in our series there was even earlier oral feeding. Shouma et al. reported no significant difference in the start of oral feeding in their adult series. The limitations of our study are: the choice of the 40 min difference created a statistically significant difference in operative time between the groups which might not be considered a truly clinically important difference. In addition, the single author operating for both approaches, which might create a bias, however the author has sufficient experience in both approaches. Moreover, although there were significant differences in hospital stay and intestinal movement between the two groups, it is not clear if these were of clinical significance.

Both transperitoneal and retroperitoneal approaches have high success rate. The shorter operative time, shorter hospital stay, rapid recovery of intestinal movement and early resumption of oral feeding are in favor with the retroperitoneal approach.