Intra-abdominal pressure and intra-abdominal hypertension in critically ill obstetric patients: a prospective cohort study.

BACKGROUND: Critically ill obstetric patients may have risk factors for intra-abdominal hypertension. This study evaluated the intra-abdominal pressure and its effect on organ function and the epidemiology of intra-abdominal hypertension.
METHODS: Obstetric patients admitted to an Intensive Care Unit, with an anticipated stay greater than 24hours, were included. Intra-abdominal pressure was measured daily via a Foley catheter, based on intravesical pressure.
RESULTS: One-hundred-and-one patients were enrolled. The intra-abdominal pressure was 5-7mmHg in 34%; 7-12mmHg in 60%; and ≥12mmHg (intra-abdominal hypertension) in 6%. All six patients with intra-abdominal hypertension were pregnant at the time of admission. The intra-abdominal pressure in four patients normalized to <12mmHg following delivery, but in the remaining two it persisted ≥12mmHg and both these patients died. Correlation between intra-abdominal pressure and organ dysfunction was weak (r=0.211). Statistical comparison between patients with and without intra-abdominal hypertension for risk factors, daily intra-abdominal pressures, and Sequential Organ Failure Assessment score could not be done due to the disproportionately small number of patients with intra-abdominal hypertension as opposed to those without (6 versus 95). Intra-abdominal pressure did not significantly differ between survivors and non-survivors (8.5±1.1 vs 7.9±1.7mmHg, P=0.079).
CONCLUSIONS: The incidence of intra-abdominal hypertension in critically ill obstetric patients was lower than previously defined for mixed Intensive Care Unit populations, with an association with the pregnant state. Normalization of intra-abdominal pressure after delivery was associated with better survival. There was no correlation between intra-abdominal pressure and organ function or mortality.