Intra-abdominal hypertension in postoperative cardiac surgery patients

Objective: To investigate screening variables identifying patients at risk of developing intra-abdominal hypertension (IAH) after cardiac surgery. Design and setting: Prospective observational study in a tertiary general intensive care unit. Participants: One hundred and eight patients admitted to the ICU after cardiac surgery, with measurements of intraabdominal pressure (IAP). Main outcome measures: Routinely collected clinical, physiological and biochemical variables were analysed with at least twice-daily measurements of IAP during the postoperative stay in the ICU. Variables available within 24 hours of admission to the ICU were evaluated against the incidence of IAH using logistic regression analysis to develop a set of screening criteria to identify patients at risk. Results: Fifty patients (46%) developed IAH during their stay in the ICU and were ventilated for longer, needed more vasopressors and stayed one more day in the ICU. Plasma albumin concentration, central venous pressure, minimal abdominal perfusion pressure, cardiopulmonary and aortic cross-clamp times and the presence of abdominal distension within the first 24 hours were associated with the occurrence of IAH. A logistic regression model using these variables correctly identified 85% of patients who developed IAH. Conclusions: A set of screening criteria routinely available within the first 24 hours of admission to the ICU after cardiac surgery could correctly identify most patients at risk of IAH.