Intraabdominal hypertension and abdominal compartment syndrome in the intensive care unit

Intraabdominal hypertension can induce a significant dysfunction of cardiovascular, respiratory, renal, and gastrointestinal and central nervous systems. Recently, a prospective multicenter epidemiological study concluded that the intraabdominal hypertension observed in intensive care units was associated with an increased risk of mortality in critically ill patients. In this review, we summarize current literature data concerning definitions and measurement of intraabdominal pressure and discuss the importance of intraabdominal hypertension in critically ill patients. We conclude that intraabdominal pressure should be taken into consideration along with other standard pressure measurements in critically ill patients. DANIELA BANDIĆ PAVLOVIĆ( ) • VIŠNJA MAJERIĆ KOGLER Department of Anesthesiology and Intensive Care Unit University Hospital Center Zagreb, Zagreb, Croatia e-mail: [email protected] Intraabdominal hypertension and measurement of the IAP IAP is measured directly by an intraperitoneal catheter or indirectly by a percutaneous inferior vena cava catheter, nasogastric catheter or urinary bladder catheter. Intravesicular pressure (IVP) measurement is now accepted as the gold standard because this method is simple, considerably accurate and widely available. In 1984 Kron et al. first described the method of IVP measurement in ACS after ruptured abdominal aortic aneurysm (3). IAP should be measured at end-expiration, in the supine position, after the bladder is firstly fully emptied, and then filled with 50 ml of saline. The degree of muscle relaxation as well as body weight has an affect on the measurement. Continuous IAP measurement using a nasogastric tube as well as continuous bladder irigation methods are now automated and they represent the most accurate methods in clinical practice. Different authors use different cut-off points for defining IAH (4,5,6,7). Sugrue et al. reported that even IAP of 10 mmHg (1mmHg = 1.36 cm H2O) might induce harm to several organ systems (6). Recently, at the World Congress on Abdominal Compartment Syndrome, the threshold for IAH was established as a value of 12 mmHg or greater in a minimum of three standardized measurements taken four to six hours apart (8). Four severity groups have been established on to basis of intraabdominal pressure values: grade 1, 12-15 mmHg; grade 2, 16-20 mmHg; grade 3, 21-25 mmHg; grade 4, greater than 25 mmHg (8). Intraabdominal hypertension induces organ system failure Current data concerning the IAH and ACS is rather large, but definitions are not clear. Malbrain et al. defined ACS as IAH greater than 20 mmHg in combination with at least one end-organ failure (2). Mc Nellis et al. defined ACS in surgical ICUs as IAP greater than 25 DANIELA BANDIĆ PAVLOVIĆ • VIŠNJA MAJERIĆ KOGLER REVIEW SIGNA VITAE 2006; 1(1): 13 15