Pediatric robotic-assisted laparoscopic pyeloplasty (RALP): does weight matter?

Purpose: RALP is rapidly becoming the new gold standard treatment for UPJO in children, who suffer from uretero-pelvic obstruction (UPJO). However, presently there is a lack of data regarding the outcomes of RALP in young infants and smaller children. This study aims to compare the outcomes of RALP in children weighing less than 10 kg and matched with an analogous cohort who underwent open pyeloplasty (OP).

Methods: We prospectively compared patients who underwent RALP to a matched cohort of patients who underwent OP from our retrospectively acquired data registry. Comparative outcomes included: Demographics, success rate, complications, and length of hospital stay, postoperative pain score and failure rate. Failure was defined as the need for a secondary intervention for UPJO, or worsening hydronephrosis during follow-up.

Results: A total of 15 patients with a median age of 8 months (range 5-11 months) and median weight 7 kg (range 5.6-9.8 kg) underwent RALP between 2016 and 2018, a matched cohort of 15 children who underwent OP similar in terms of age, weight, gender and affected side between 2014 and 2016. All children had prenatal diagnosis of hydronephrosis and underwent surgery utilizing combined general and regional (Caudal MO) anesthesia. Intrinsic obstruction was present in 13 of RALP group (86.7%) and in 14 in OP group (93.3%). Mean operative time was 67.8 + 13.4 min in RALP group, while 66.5 + 9.5 min in OP group. (p = 0.76) All but two patients in RALP group had stent inserted and required subsequent anesthesia for stent removal, while all OP children had a Salle Pyeloplasty stent inserted during the procedure and underwent removal in an ambulatory setting without the need for anesthesia. There were no failures recorded in the RALP group, while one patient in OP required a secondary intervention. Mean hospital stay was 1 day (1-2 days) for RALP and 2 days (2-3 days) for OP. There was no difference in FLACC Pain Scale in both groups. Clavien-Dindo grade I-II complications occurred in one patient from each group. Two patients from RALP underwent subsequent ureteral reimplantation due to accompanying uretero-vescical junction obstruction.

Conclusions: Our data suggest that RALP can be performed safely in pediatric patients weighing less than 10 kg. with similar outcomes when compared to patients undergoing an open procedure for the same pathology.