536 Association of neonatal birthweight with shoulder dystocia management

Abstract

To evaluate maneuvers associated with shoulder dystocia resolution in patients delivering neonates with a birthweight >4000g compared to <4000g This is a retrospective cohort of patients who delivered between September 2014 and August 2018 at a tertiary care center whose delivery was complicated by shoulder dystocia. The proportion of patients who underwent a maneuver beyond McRoberts was compared between patients who delivered neonates with birthweight >4000g vs <4000g. Secondary outcomes included total number of maneuvers, specific maneuvers performed, final maneuver prior to delivery, maternal trauma, dystocia length and neonatal morbidity. Continuous and categorical variables were evaluated using Wilcoxon rank sum and Fisher’s exact test. Relative risks were calculated with a confidence interval (CI) of 95% being considered significant. Of the 481 patients meeting study criteria, 9 were excluded due to lack of informative data. Patients with a neonate weighing >4000g (n=156, 33.0%), compared to those with a neonate weighing 35 (42.2% vs 30.1%) and less likely to undergo operative delivery (4.5% vs 10.8%). Patients with a neonate weighing >4000g were more likely to undergo a maneuver beyond McRoberts (RR 1.24, CI 1.08-1.42); and remained so after adjusting for BMI, diabetes and operative delivery (aRR 1.26, CI 1.06-1.41). Patients with a neonate weighing >4000g were more likely to have a 3rd/4th degree laceration (RR 2.62, CI 1.43-4.79), have a dystocia lasting >90 seconds (RR 1.63, CI 1.12-2.37) and had a higher mean total of maneuvers performed (2.2 vs 1.9 p=value 0.004). Neonates weighing >4000g were more likely to have brachial plexus injury (RR 5.1, CI 1.62-15.94) and clavicular fracture (RR 3.77, CI 1.54-9.27). Patients with neonates weighing >4000g, as compared to <4000g, are more likely to undergo a maneuver beyond McRoberts during shoulder dystocia. Further data is needed to evaluate if shoulder dystocia management should be guided by suspected fetal weight.