Retroperitoneal compartment pressure elevation impairs pancreatic tissue blood flow.

Objectives: To investigate whether the increase of the retroperitoneal compartment pressure, as in the case of peripancreatic fluid accumulation in severe acute pancreatitis, simulated by infusing a colloid fluid into the retroperitoneum, has any effect on pancreatic tissue blood flow.

Methods: Six male anesthetized swine were subjected to a transcutaneous placement of catheters into the retroperitoneal space. Through these catheters, a colloid solution was infused, under continuous retroperitoneal pressure monitoring, to achieve a pressure up to 20 mm Hg. Pancreatic tissue blood flow was assessed by colored microsphere injection technique, and pancreatic interstitial pressure was measured by means of a commercially available pressure monitor system before and after the distension of the retroperitoneal space, allowing the appropriate time for the animals to be stabilized from any intervention.

Results: The increase in the retroperitoneal compartment pressure was found to significantly increase pancreatic interstitial pressure (from 8 +/- 1 to 20 +/- 2.4 mm Hg, P = 0.001) as well as reduce pancreatic tissue blood flow (from 1.75 +/- 0.4 to 0.56 +/- 0.12 mL . min . g, P = 0.002).

Conclusions: The increase of retroperitoneal pressure leads to an impairment of pancreatic tissue blood flow in the healthy pancreas. Although these findings support the hypothesis that peripancreatic fluid collection during the course of acute pancreatitis could contribute or augment pancreatic tissue ischemia, further assessment is necessary.