Risk for and disparities in critical care during delivery hospitalizations

Abstract

Need for critical care during delivery hospitalizations may be an important maternal outcome measure, but it is not well characterized. This study aimed to characterize the risks and disparities in critical care diagnoses and interventions during delivery hospitalizations. This serial cross-sectional study used the 2000-2014 National Inpatient Sample. Here, the primary outcome was a composite of critical care interventions and diagnoses, including mechanical ventilation and intubation, central monitoring, septicemia, coma, acute cerebrovascular disease, extracorporeal membrane oxygenation, Swan-Ganz catheter monitoring, cardiac rhythm conversion, and respiratory failure. Temporal trends, risk of death, and the proportion of deaths with a critical care composite diagnosis were determined. Unadjusted and adjusted log-linear regression models were fit with a critical care composite as the outcome, adjusting for demographic, clinical, and hospital factors. To evaluate the role of critical care interventions in disparities, analyses were stratified by maternal race and ethnicity. Of 45.8 million deliveries identified, 0.21% had a critical care procedure or diagnosis during the delivery hospitalization. Overall, 75.8% of maternal deaths had an associated diagnosis from a critical care composite. The critical composite increased from 17.9 to 30.3 per 10,000 deliveries from 2000 to 2014 with an average annual percentage change of 3.4% (95% confidence interval, 1.3-5.5). Mechanical ventilation and intubation (21.5% of cases) and respiratory failure (54.8% of cases) were the most common diagnoses present in the composite. Although non-Hispanic black women were at 32.4% higher risk than non-Hispanic white women to die in the setting of a critical care diagnosis (2.2% vs 1.7%; P<.01), they were 162% more likely to have a critical care diagnosis (risk ratio, 2.62; 95% confidence interval, 2.58-2.66). Of clinical factors, primary cesarean delivery (adjusted relative risk, 7.54; 95% confidence interval, 7.43-7.65), postpartum hemorrhage (adjusted relative risk, 5.11; 95% confidence interval, 5.02-5.19), and chronic kidney disease (adjusted relative risk, 4.06; 95% confidence interval, 3.89-4.23) were associated with the highest adjusted risk of a critical care composite. Three-quarters of maternal deaths were associated with a critical care diagnosis or procedure. The rate of critical care during delivery hospitalizations increased over the study period. Maternal mortality disparities may result from risks of conditions that require critical care rather than the care received once a critical care condition has developed.