Long-term trends in the incidence and management of shoulder dystocia in a tertiary obstetric unit in Hong Kong.

INTRODUCTION: Because there have been changes in the management of macrosomic pregnancies and shoulder dystocia in the past decade, this study was conducted to compare the incidences of shoulder dystocia and perinatal outcomes between the periods of 2000-2009 and 2010-2019. METHODS: This retrospective study was conducted in a tertiary obstetric unit. All cases of shoulder dystocia were identified using the hospital's electronic database. The incidences, maternal and fetal characteristics, obstetric management methods, and perinatal outcomes were compared between the two study periods. RESULTS: The overall incidence of shoulder dystocia decreased from 0.23% (134/58 326) in 2000-2009 to 0.16% (108/65 683) in 2010-2019 (P=0.009), mainly because of the overall decline in the proportion of babies with macrosomia (from 3.3% to 2.3%; P<0.001). The improved success rates of the McRoberts' manoeuvre (from 31.3% to 47.2%; P=0.012) and posterior arm extraction (from 52.9% to 92.3%; P=0.042) allowed a greater proportion of affected babies to be delivered within 2 minutes (from 59.0% to 79.6%; P=0.003). These changes led to a significant reduction in the proportion of fetuses with low Apgar scores: <5 at 1 minute of life (from 13.4% to 5.6%; P=0.042) and <7 at 5 minutes of life (from 11.9% to 4.6%; P=0.045). CONCLUSION: More proactive management of macrosomic pregnancies and enhanced training in the acute management of shoulder dystocia led to significant improvements in shoulder dystocia incidence and perinatal outcomes from 2000-2009 to 2010-2019.

Impact of simulation training on the management of shoulder dystocia and incidence of permanent brachial plexus birth injury: An observational study.

OBJECTIVE: To study the impact of shoulder dystocia (SD) simulation training on the management of SD and the incidence of permanent brachial plexus birth injury (BPBI). DESIGN: Retrospective observational study. SETTING: Helsinki University Women's Hospital, Finland. SAMPLE: Deliveries with SD. METHODS: Multi-professional, regular and systematic simulation training for obstetric emergencies began in 2015, and SD was one of the main themes. A study was conducted to assess changes in SD management and the incidence of permanent BPBI. The study period was from 2010 to 2019; years 2010-2014 were considered the pre-training period and years 2015-2019 were considered the post-training period. MAIN OUTCOME MEASURES: The primary outcome measure was the incidence of permanent BPBI after the implementation of systematic simulation training. Changes in the management of SD were also analysed. RESULTS: During the study period, 113 085 vertex deliveries were recorded. The incidence of major SD risk factors (gestational diabetes, induction of labour, vacuum extraction) increased and was significantly higher for each of these factors during the post-training period (p < 0.001). The incidence of SD also increased significantly (0.01% vs 0.3%, p < 0.001) during the study period, but the number of children with permanent BPBI decreased by 55% after the implementation of systematic simulation training (0.05% vs 0.02%, p < 0.001). The most significant change in the management of SD was the increased incidence of successful delivery of the posterior arm. CONCLUSIONS: Systematic simulation-based training of midwives and doctors can translate into improved individual and team performance and can significantly reduce the incidence of permanent BPBI.

Impact of fetal manipulation on maternal and neonatal severe morbidity during shoulder dystocia management.

PURPOSE: There are few data on maternal and neonatal morbidities associated with shoulder dystocia (SD), depending on the use of fetal manipulation (FM). A prior 5-year study was conducted in our center in 2012 for this purpose. Our objective was to compare severe maternal and neonatal morbidities according to FM execution in a larger cohort. METHODS: We conducted a retrospective study between 2007 and 2020. SD was considered when additional maneuvers were required to complete a delivery. Severe maternal morbidity was defined as the occurrence of obstetric anal sphincter injury (OASI). Severe neonatal morbidity was defined as Apgar < 7 at 5 min and/or cord arterial pH < 7.1 and/or or a permanent brachial plexus palsy. We studied these data in the FM group compared to the non- FM group. RESULTS: FM was associated with increased OASI rates (21.1% vs. 3.8%, OR = 6.72 [2.7-15.8]). We found no significant difference in severe neonatal morbidity. Maternal age > 35 and FM appear to be associated with the occurrence of OASI, with ORa = 13.3 [1.5-121.8] and ORa = 5.3 [2.2-12.8], respectively. FM was the only factor associated with the occurrence of severe neonatal morbidity (ORa = 2.3 [1.1-4.8]. The rate of episiotomy was significantly decreased (20% versus 5% p < 0.05) and there was an increase in the rate of SD managed with FM in our center. CONCLUSION: FM is the only factor associated with an increased risk of OASI. In case of failure of non-FM maneuvers, the rapid implementation of FM maneuvers resulted in no difference regarding severe neonatal morbidity.

Risk assessment of shoulder dystocia via the difference between transverse abdominal and biparietal diameters: A retrospective observational cohort study.

Shoulder dystocia is defined as vaginal cephalic delivery that requires additional obstetric maneuvers to deliver the fetus after the head has been delivered and gentle traction has failed. A bigger difference between the transverse abdominal diameter (TAD) (abdominal circumference [AC]/π) and biparietal diameter (BPD) (TAD-BPD) has been reported as a risk factor for shoulder dystocia in different countries; however, it remains unclear if this relationship is relevant in Japan. This study aimed to clarify the association between TAD-BPD and shoulder dystocia after adjusting for potential confounding factors in a Japanese cohort. We retrospectively examined 1,866 Japanese women who delivered vaginally between 37+0 and 41+6 weeks of gestation at the University of Yamanashi Hospital between June 2012 and November 2018. The cutoff value of TAD-BPD associated with shoulder dystocia and the association between TAD-BPD and shoulder dystocia were evaluated. The mean maternal age was 32.5±5.3 years; the patients included 1,053 nulliparous women (57.5%), 915 male infants (49.0%), 154 women with gestational diabetes mellitus (GDM) (8.3%), and 5 infants with macrosomia (0.3%). The mean TAD-BPD was 9.03±4.7 mm. The overall incidence of shoulder dystocia was 2.4% (44/1866). The cutoff value to predict shoulder dystocia was 12.0 mm (sensitivity, 61.4%; specificity, 73.8%; likelihood ratio, 2.34; positive predictive value, 5.4%; negative predictive value, 98.8%). We then used a multivariable logistic regression analysis to examine the association between TAD-BPD and shoulder dystocia while controlling for the potential confounding factors. In multivariate analyses, TAD-BPD ≥12.0 mm (adjusted odds ratio [OR], 4.39; 95% confidence interval [CI], 2.35-8.18) and GDM (adjusted OR, 3.59; 95% CI, 1.71-7.52) were associated with shoulder dystocia. Although TAD-BPD appears to be a relevant risk factor for shoulder dystocia, sonographic fetal anthropometric measures do not appear to be useful in screening for shoulder dystocia due to a low positive predictive value.

Assessment of Current Epidemiology and Risk Factors Surrounding Brachial Plexus Birth Palsy.

PURPOSE: Brachial plexus birth palsy (BPBP) is common; however, the current incidence is unknown and more than 50% of infants with BPBP have no known risk factors. The purpose of this study was to determine the current incidence of BPBP, assess known risk factors, and evaluate hypotonia as a new risk factor, as well as estimate the length of stay (LOS) and direct costs of children with an associated BPBP injury. METHODS: Data from the 1997 to 2012 Kids' Inpatient Database data sets were evaluated to identify patients with a BPBP injury and various risk factors. Evaluation of LOS data and direct costs was also performed. Multivariable logistic regression analysis was utilized to assess the association of BPBP with its known and previously undescribed risk factors. RESULTS: The incidence of BPBP has steadily decreased from 1997 to 2012, with an incidence of 0.9 ± 0.01 per 1,000 live births recorded in 2012. Shoulder dystocia is the number 1 risk factor for the development of a BPBP injury. Hypotonia is a newly recognized risk factor for the development of BPBP. Fifty-five percent of infants with BPBP have no known perinatal risk factors. The initial hospital LOS is approximately 20% longer for children with a BPBP injury and the hospital stay direct costs are approximately 40% higher. CONCLUSIONS: The incidence of BPBP is decreasing over time. Shoulder dystocia continues to be the most common risk factor for sustaining a BPBP injury. Children with a BPBP injury have longer LOSs and hospital direct costs compared with children without a BPBP injury. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic II.