Outcome analysis of vesicoamniotic shunting in a comprehensive population

Purpose: Prenatal detection of obstructive uropathy is used widely and vesi coamniotic shunting is the accepted procedure in well-defined cases. We pre sent outcomes of vesicoamniotic shunting in a consecutive series from a coo rdinated prenatal-postnatal treatment program. Materials and Methods: From 1989 to 1998 bladder obstruction was identified in 89 fetuses at a multidisciplinary prenatal high risk clinic. Prenatal i ntervention was considered in cases of bilateral hydronephrosis associated with evidence of bladder outlet obstruction and oligohydramnios. Results: Indications for prenatal shunting were present in 12 patients (13% ), and 9 underwent vesicoamniotic shunt insertion between weeks 20 and 28 o f gestation. None of the prenatal procedures was associated with preterm la bor, chorioamnionitis or urine chemistry values greater than cutoff thresho ld on bladder tap. Shunts were extruded from 2 fetuses, which required sequ ential insertion. After prenatal intervention I patient elected pregnancy t ermination and the others proceeded to term. Two neonates died at birth, an d 6 survived. The underlying urological diagnosis was posterior urethral va lves in 4 newborns, urethral atresia in 1, and prune belly variant and uret hral atresia in 1. Of the patients 3 had relatively normal renal function, 2 had severe renal insufficiency and 1 had mild renal impairment. Five newb orns are voiding freely and 1 underwent bladder reconstruction and is on in termittent catheterization. None of the patients had pulmonary problems at last followup. Conclusions: Although vesicoamniotic shunting is effective in reversing oli gohydramnios, its ability to achieve sustainable good renal function in inf ancy is variable. No specific prenatal parameters were effective in predict ing eventual good renal function. Pulmonary function cannot be assured with restoration of amniotic fluid.