Intra-abdominal pressure and abdominal perfusion pressure in cirrhotic patients with septic shock

BACKGROUND: The importance of intra-abdominal pressure (IAP) and abdominal perfusion pressure (APP) in cirrhotic patients with septic shock is not well studied. We evaluated the relationship between IAP and APP and outcomes of cirrhotic septic patients, and assessed the ability of these measures compared to other common resuscitative endpoints to differentiate survivors from nonsurvivors. METHODS: This study was a post hoc analysis of a randomized double-blind placebo-controlled trial in which mean arterial pressure (MAP), central venous oxygen saturation (ScvO(2)) and IAP were measured every 6 h in 61 cirrhotic septic patients admitted to the intensive care unit. APP was calculated as MAP - IAP. Intra-abdominal hypertension (IAH) was defined as mean IAP ≥ 12 mmHg, and abdominal hypoperfusion as mean APP < 60 mmHg. Measured outcomes included ICU and hospital mortality, need for renal replacement therapy (RRT) and ventilator- and vasopressor-free days. RESULTS: IAH prevalence on the first ICU day was 82%, and incidence in the first 7 days was 97%. Compared to patients with normal IAP, IAH patients had significantly higher ICU mortality (74.0% vs. 27.3%, p = 0.005), required more RRT (78.0% vs. 45.5%, p = 0.06) and had lower ventilator- and vasopressor-free days. On a multivariate logistic regression analysis, IAH was an independent predictor of both ICU mortality (odds ratio (OR), 12.20; 95% confidence interval (CI), 1.92 to 77.31, p = 0.008) and need for RRT (OR, 6.78; 95% CI, 1.29 to 35.70, p = 0.02). Using receiver operating characteristic curves, IAP (area under the curve (AUC) = 0.74, p = 0.004), APP (AUC = 0.71, p = 0.01), Acute Physiology and Chronic Health Evaluation II score (AUC = 0.71, p = 0.02), but not MAP, differentiated survivors from nonsurvivors. CONCLUSIONS: IAH is highly prevalent in cirrhotic patients with septic shock and is associated with increased ICU morbidity and mortality.