Indications for intensive care unit transfer during delivery hospitalizations: a retrospective cohort study using the...

Approximately one-quarter of intensive care unit admissions include a severe maternal morbidity event. We hypothesized that non-severe maternal morbidity intensive care unit admissions would have an increased need for intensive care unit-specific services compared to admissions with severe maternal morbidity.

We conducted a retrospective cohort study using the Premier Database to examine delivery hospitalizations that included intensive care unit admissions (10/2015-12/2020). We used ICD-10 codes to identify severe maternal morbidity and charge codes to identify services usually provided in intensive care units. We performed descriptive analyses for intensive care unit service codes and multivariable logistic regression to assess factors associated with admissions in patients with no codes for severe maternal morbidity.

Among 4.8 million delivery hospitalizations, 35,837 patients were admitted to the intensive care unit. Of intensive care unit admissions, 9,803 (27.4%) met severe maternal morbidity criteria. Intensive care unit-specific charge codes were more commonly charged to patients with severe maternal morbidity compared to those without severe maternal morbidity: invasive blood pressure monitoring (21.0% vs. 3.8%) and invasive hemodynamic monitoring (2.0% vs. 0.2%). Codes for intravenous fluid amounts suggest that severe maternal morbidity patients received higher volumes of intravenous fluid. Median intensive care unit length of stay was similar between groups. Comorbidities such as cardiomyopathy and preeclampsia were associated with increased non-severe maternal morbidity intensive care unit admission.

Intensive care unit admission may be driven by concern for clinical deterioration among patients with high-risk comorbidities rather than the presence of severe maternal morbidity.