Interventions to decrease complications after shoulder dystocia: a systematic review and Bayesian meta-analysis.

Objective: This study aimed to evaluate the outcomes associated with the implementation of simulation exercises to reduce the sequela of shoulder dystocia.

Data Sources: Electronic databases (Ovid MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature database, and Scopus) were initially queried in June 2020 and updated in November 2020. The following 3 concepts were introduced and refined using the controlled vocabulary of the database: vaginal birth, shoulder dystocia, and simulation training. There were no limitations to the year of publication as part of the search strategy.

Study Eligibility Criteria: We included all studies that reported on the frequency of shoulder dystocia and the associated complications before and after the implementation of interventional exercises to improve outcomes.

Methods: Two authors independently assessed the abstracts and full-text articles of all studies for eligibility and evaluated the quality of the included studies using the Newcastle-Ottawa Scale. Any inconsistencies related to study evaluation or data extraction were resolved by a third author. The coprimary outcomes of this systematic review and meta-analysis were neonatal brachial plexus palsy diagnosed following deliveries complicated by shoulder dystocia and persistence of brachial palsy at 12 months or later. The secondary outcomes were the frequency of shoulder dystocia and cesarean delivery. Study effects were combined using a Bayesian meta-analysis and were reported as risk ratios and 95% credible intervals (Crs).

Results: Of the 372 articles reviewed, 16 publications, which included 428,552 deliveries with 217,713 (50.8%) deliveries during the preintervention and 210,839 (49.2%) deliveries during the postinterventional period, were included in the meta-analysis. The incidence of neonatal brachial plexus palsy after shoulder dystocia decreased from 12.1% to 5.7% (risk ratio, 0.37; 95% Cr, 0.26-0.57; probability of reduction 100%). The overall proportion of neonatal brachial plexus palsy decreased, but with less precision, from 0.3% to 0.1% (risk ratio, 0.53; 95% Cr, 0.21-1.26; probability of reduction 94%). Two studies followed newborns with brachial plexus palsy for at least 12 months. One study that reported on persistent neonatal brachial plexus palsy at 12 months among 1148 shoulder dystocia cases noted a reduction in persistent neonatal brachial plexus palsy from 1.9% to 0.2% of shoulder dystocia cases (risk ratio, 0.13; 95% confidence interval, 0.04-0.49). In contrast, the study that reported on persistent neonatal brachial plexus palsy at 12 months for all deliveries noted that it did not change significantly, namely from 0.3 to 0.2 per 1000 births (risk ratio, 0.77; 95% confidence interval, 0.31-1.90). Following the implementation of shoulder dystocia interventional exercises, the diagnosis of shoulder dystocia increased significantly from 1.2% to 1.7% of vaginal deliveries (risk ratio, 1.39; 95% Cr, 1.19-1.65; probability of increase 100%). Compared with the preimplementation period, the cesarean delivery rate increased postimplementation from 21.2% to 25.9% (risk ratio, 1.22; 95% Cr, 0.93-1.59; probability of increase 93%). We created an online tool (https://ccrebm-bell.shinyapps.io/sdmeta/) that permits calculation of the absolute risk reduction and absolute risk increase attributable to the intervention vis-à-vis the incidence of shoulder dystocia, neonatal brachial plexus palsy, and cesarean deliveries.

Conclusion: Introduction of shoulder dystocia interventional exercises decreased the rate of neonatal brachial plexus palsy per shoulder dystocia case; the data on persistence of neonatal brachial plexus palsy beyond 12 months is limited and contradictory. Implementation of the interventions was associated with an increase in the diagnosis of shoulder dystocia and rate of cesarean deliveries.