Measuring the impact of maternal critical care admission on short- and longer-term maternal and birth outcomes

Factors increasing the risk of maternal critical illness are rising in prevalence in maternity populations. Studies of general critical care populations highlight that severe illness is associated with longer-term physical and psychological morbidity. We aimed to compare short- and longer-term outcomes between women who required critical care admission during pregnancy/puerperium and those who did not. This is a cohort study including all women delivering in Scottish hospitals between 01/01/2005 and 31/12/2018, using national healthcare databases. The primary exposure was intensive care unit (ICU) admission, while secondary exposures included high dependency unit admission. Outcomes included hospital readmission (1-year post-hospital discharge, 1-year mortality, psychiatric hospital admission, stillbirth, and neonatal critical care admission). Multivariable Cox and logistic regression were used to report hazard ratios (HR) and odds ratios (OR) of association between ICU admission and outcomes. Of 762,918 deliveries, 1449 (0.18%) women were admitted to ICU, most commonly due to post-partum hemorrhage (225, 15.5%) followed by eclampsia/pre-eclampsia (133, 9.2%). Over-half (53.8%) required mechanical ventilation. One-year hospital readmission was more frequent in women admitted to ICU compared with non-ICU populations [24.5% (n = 299) vs 8.9% (n = 68,029)]. This association persisted after confounder adjustment (HR 1.93, 95% confidence interval [CI] 1.33, 2.81, p < 0.001). Furthermore, maternal ICU admission was associated with increased 1-year mortality (HR 40.06, 95% CI 24.04, 66.76, p < 0.001), stillbirth (OR 12.31, 95% CI 7.95,19.08, p < 0.001) and neonatal critical care admission (OR 6.99, 95% CI 5.64,8.67, p < 0.001) after confounder adjustment. Critical care admission increases the risk of adverse short-term and long-term maternal, pregnancy and neonatal outcomes. Optimizing long-term post-partum care may benefit maternal critical illness survivors.