Closure techniques for fetoscopic access sites in the rabbit at mid-gestation

Abstract

Operative fetoscopy may be limited by its relatively high associated risk of preterm prelabour rupture of membranes. The objective of this study was to study closure techniques of the access site for fetoscopy in the mid-gestational rabbit. A total of 32 does (288 amniotic sacs) at 22 days gestational age (GA; term = 32 days) underwent 14 gauge needle fetoscopy, by puncture through surgically exposed amnion. Entry site was randomly allocated to four closure technique groups: myometrial suture (n = 14), fibrin sealant (n = 15), autologous maternal blood plug (n = 13), collagen plug (n = 14); 16 sacs were left unclosed (positive controls), and the unmanipulated 216 sacs were negative controls. Membrane integrity, presence of amniotic fluid and fetal lung to body weight ratio (FLBWR) were evaluated at 31 days GA. Following fetoscopy without an attempt to close the membranes, amniotic integrity was restored in 41% of cases (amniotic integrity in controls 94%; P = 0.00001). When the access site was surgically closed, the amnion resealed in 20-44% of cases, but none of the tested techniques was significantly better than the others or than positive controls. Permanent amniotic disruption was associated with a significantly lower FLBWR in all groups. In conclusion, the rate of fetoscopy-induced permanent membrane defects in this model did not improve by using any of the closure techniques tested here.