WITHDRAWN: Recurrent UPJ obstruction following paediatric pyeloplasty is associated with an initial <2.5cm incision open surgical approach

Objectives To determine the risk factors that affect surgical outcomes for pediatric pyeloplasty, and whether this may be related to the choice of operative approach. Methods A retrospective cohort study was performed to evaluate clinicodemographic and operative characteristics of children undergoing dismemberment pyeloplasty by 2 senior pediatric urologists in our tertiary institution between Jan 2008 - Dec 2017. Outcomes included overall complications, re-stenosis, and revision pyeloplasty based on clinic-radiological parameters. Bivariate analysis with Chi-square and Mann-Whitney U test followed by multivariate logistic regression with backward likelihood analysis determined an adjusted effect estimate of the identified significant indicators for inferior peri-operative outcomes related to management. Results A total of 185 (93 open, 92 Laparoscopic) cases with an average follow-up of 31.3±27.4 months were analyzed. Complications occurred in 21 (11.4%) patients. 12 (6.5%) experienced recurrent UPJ obstruction with 10 (5.4%) undergoing redo-pyeloplasty. Of these, 9 were performed open and 1 laparoscopically. Multivariate logistic regression identified open pyeloplasty as an independent predictor for overall complications (HR 3.29, 95%CI 1.14, 9.51), recurrent UPJ obstruction (HR 49.8, 95%CI 3.09, 803.2) and redo-pyeloplasty (HR 9.75, 95%CI 1.21, 78.6) compared to a laparoscopic approach. Missed crossing vessels were identified in seven redo-cases, which all were from prior open pyeloplasty. Conclusions An initial open approach was identified as an independent predictor of future complications due to a higher incidence missed crossing vessels at initial repair. Surgeons need to remain especially mindful of this phenomenon when working in a confined open field.