Obstetric admissions to intensive care units in Australia and New Zealand: a registry-based cohort study.

Abstract

Describe the epidemiology of obstetric patients admitted to an Intensive Care Unit (ICU). Registry-based cohort study. One hundred and eighty-three ICUs in Australia and New Zealand. Women aged 15-49years, admitted to ICU between 2008 and 2017, classified as pregnant, postpartum or with an obstetric-related diagnosis. Data were extracted from the Australia and New Zealand Intensive Care Society (ANZICS) Adult Patient Database and national agencies. Incidence of ICU admission, cohort characteristics, maternal outcomes and changes over time. The cohort comprised 16063 patients. The annual number of obstetric ICU admissions increased, whereas their proportion of total ICU admissions (1.3%) did not change (odds ratio 1.02, 95% CI 0.99-1.04, P=0.14). There were 10518 (65%) with an obstetric-related ICU diagnosis, and 5545 (35%) with a non-obstetric ICU diagnosis. Mean (SD) age was 31 (6.4) years, 1463 (9.1%) were Indigenous, 2305 (14%) were transferred from another hospital, and 3008 (19%) received mechanical ventilation. Median [IQR] length of stay in hospital was 5.2 [3.1-7.9] days, which included 1.1 [0.7-1.8] days in ICU. There were 108 (0.7%) maternal deaths, most (n=97, 90%) having a non-obstetric diagnosis. There was no change in risk-adjusted length of stay or mortality over time. Obstetric patients account for a stable proportion of ICU admissions in Australia and New Zealand. These patients typically have a short length of ICU stay and low hospital mortality. Obstetric patients in Australia/New Zealand ICUs have a short length of ICU stay and low mortality.