Development of clinical risk-prediction models for uterine atony following vaginal and cesarean delivery.

BACKGROUND: Uterine atony is the most common cause of postpartum hemorrhage and is associated with substantial morbidity. Prospectively identifying women at increased risk of atony may reduce the incidence of subsequent adverse events. We sought to develop and evaluate clinical risk-prediction models for uterine atony following vaginal and cesarean delivery, using prespecified risk factors identified from systematic review. METHODS: Using retrospective data from vaginal and cesarean deliveries occurring at a single institution between 2010 and 2019, antepartum and intrapartum risk-prediction models for uterine atony, defined by supplementary uterotonic administration in addition to prophylactic oxytocin infusion, were developed using logistic regression. The C-statistic quantified the ability of the model to discriminate between cases and controls. RESULTS: Data were available for 4773 atony cases and 23 933 controls. The antepartum model included 20 risk factors and exhibited moderate discriminatory ability (C-statistic 0.61, 95% confidence interval 0.60 to 0.62). The intrapartum model included 27 risk factors and showed improved discriminatory ability (C-statistic 0.68, 95% confidence interval 0.67 to 0.69). CONCLUSIONS: We identified antepartum and intrapartum risk-prediction models to quantify patients' risk of uterine atony. Models performed similarly for all delivery modes, races, and ethnic groups. Future work should further improve these models through inclusion of more comprehensive prediction data.

Mode of anaesthesia for preterm Caesarean delivery: secondary analysis from the Maternal-Fetal Medicine Units Network Caesarean Registry.

BACKGROUND: Preterm delivery is often performed by Caesarean section. We investigated modes of anaesthesia and risk factors for general anaesthesia among women undergoing preterm Caesarean delivery. METHODS: Women undergoing Caesarean delivery between 24(+0) and 36(+6) weeks' gestation were identified from a multicentre US registry. The mode of anaesthesia was classified as neuraxial anaesthesia (spinal, epidural, or combined spinal and epidural) or general anaesthesia. Logistic regression was used to identify patient characteristic, obstetric, and peripartum risk factors associated with general anaesthesia. RESULTS: Within the study cohort, 11 539 women had preterm Caesarean delivery; 9510 (82.4%) underwent neuraxial anaesthesia and 2029 (17.6%) general anaesthesia. In our multivariate model, African-American race [adjusted odds ratio (aOR)=1.9; 95% confidence interval (CI)=1.7-2.2], Hispanic ethnicity (aOR=1.5; 95% CI=1.2-1.8), other race (aOR=1.4; 95% CI=1.1-1.9), and haemolysis, elevated liver enzymes and low platelets (HELLP) syndrome or eclampsia (aOR=2.8; 95% CI=2.2-3.5) were independently associated with receiving general anaesthesia for preterm Caesarean delivery. Women with an emergency Caesarean delivery indication had the highest odds for general anaesthesia (aOR=3.5; 95% CI=3.1-3.9). For every 1 week decrease in gestational age at delivery, the adjusted odds of general anaesthesia increased by 13%. CONCLUSIONS: In our study cohort, nearly one in five women received general anaesthesia for preterm Caesarean delivery. Although potential confounding by unmeasured factors cannot be excluded, our findings suggest that early gestational age at delivery, emergent Caesarean delivery indications, hypertensive disease, and non-Caucasian race or ethnicity are associated with general anaesthesia for preterm Caesarean delivery.