Intravenous Contrast Medium Aggravates the Impairment of Pancreatic Microcirculation in Necrotizing Pancreatitis in the Rat

Abstract

Background Previous reports demonstrated that radiographic contrast medium, as used in contrast-enhanced computed tomography, increases acinar necrosis and mortality in experimental pancreatitis. The authors studed the possibility that these changes may be related to an additional impairment of pancreatic microcirulation. Methods Fifty Wistar rats had acute pancreatitis induced by intraductal glycodeoxycholic acid (10 mmol/L for 10 min) and intravenous cerulein (5 μg/kg/hr for 6 hrs). After rehydration (16 mL/kg), pancreatic capillary perfusion was quantified by means of intravital microscopy at baseline before intravenous infusion of contrast medium (n = 25) or saline (n = 25), and 30 and 60 minutes thereafter. In addition to total capillary flow, capillaries were categorized as high-or low-flow (> or <1.6nL/min). Results Pancreatic capillary flow did not change in either high- or low-flow capillaries after saline infusion. However, contrast medium infusion induced a significant decrease of total capillary flow (p < 0.001). Analysis according to the relative flow rate revealed that this was primarity because of a significant additional reduction of perfusion in low-flow capillaries (p < 0.0001). Furthermore, complete capillary stasis was observed in 15.9 ± 3.4% after contrast medium as compared with 3.2 ± 1.2% after saline infusion (p < 0.006). Conclusion Radiographic contrast medium aggravates the impairment of pancreatic microcirculation in experimental necrotizing pancreatitis.