The experimental assessment of techniques of measuring biliary pressure

A variety of different methods have been used for the measurement of pressures during operations on the biliary tract. However, there are few data on the experimental evaluation of the methods, and there has been no controlled comparative evaluation of the most commonly used techniques. In these experiments, we have compared the manometric technique of Caroli, the syringe barrel method of Daniel and White et alii, and the constant infusion apparatus of Cushieri. The experiments were performed in pigs because of the similarity of their biliary tract to that of man. Resting and opening pressures were recorded, and flow into the duodenum via the ampulla was measured simultaneously. The manometric and syringe barrel techniques gave highly reproducible measurements of resting and opening pressure, and valid measurements of opening pressure. The constant infusion apparatus gave reproducible measurements of resting pressure, but did not measure opening pressure. The manometric technique was shown to measure changes in the resistance of the choledochoduodenal junction in response to morphine and atropine.