Characteristics of obstetric patients referred to intensive care in an Australian tertiary hospital

Background: The low mortality rate of 8.4 deaths per 100 000 women giving birth in Australia is well described; however, less is known about the spectrum of morbidity evident in pregnant and postpartum women admitted to an intensive care unit. Aim: A detailed description of the demographics, comorbidities, diagnoses and interventions of pregnant and postpartum women admitted to an Australian intensive care unit (ICU). Materials and Methods: A retrospective observational study was conducted in a large metropolitan hospital co-located with a quaternary-level maternity hospital. The participants were women admitted to intensive care between 1 January 2007 and 30 June 2009 who were pregnant at any gestational age, or within 6 weeks postpartum. Results: Two hundred and forty-nine women were admitted to ICU within the study period constituting 19 of all ICU admissions. The main reasons for admission were hypertensive disease of pregnancy and obstetric haemorrhage. The median (range) age was 32 (17-51) years, and ICU duration was 32 (8-228) h. The median APACHE III-J severity of illness score was 32 (8-80). Almost one-quarter of admissions could be classified as primarily observational. The most common interventions in ICU were invasive arterial pressure monitoring, central venous access with pressure monitoring and magnesium infusions. One-fifth of admissions were invasively ventilated. Conclusion: A substantial number of pregnant and postpartum women admitted to ICU did not receive interventions typical of other critical illness, such as mechanical ventilation, inotropes or renal replacement therapy. This confounds the use of an ICU admission as a measure of maternal morbidity.