Hemodynamic effects of acute changes in intra-abdominal pressure in patients with cirrhosis

Abstract

Background: Changes in intra-abdominal pressure (IAP) have significant circulatory effects. However, whether this may influence the gastroesophageal collateral blood flow in patients with cirrhosis has not been studied. Methods: In 14 portal hypertensive cirrhotics, serial hemodynamic measurements were obtained in baseline conditions 30 minutes after the mechanical increase of IAP by 10 mm Hg and 30 minutes after returning IAP to baseline levels. Results: Increasing IAP caused similar increases in free and wedged hepatic venous pressures (+10.3 mm Hg and +11.0 mm Hg, respectively; P < 0.005), without changing the hepatic venous pressure gradient (HVPG). However, there were significant decreases in cardiac output (−18%; P < 0.005) and hepatic blood flow (−20%; P < 0.05), whereas azygos blood flow, an index of gastroesophageal collateral blood flow, increased markedly (+23%; P < 0.005). The opposite occurred after releasing the high IAP. Conclusion: In portal hypertensive cirrhotics, acute changes in IAP did not change HVPG but markedly modified splanchnic and systemic hemodynamics. Brief elevations of IAP may have deletereous effects, as shown by the increase in azygos blood flow and the decrease in cardiac output and hepatic blood flow, whereas reduction of a high IAP causes the opposite changes and may be beneficial.