Dynamics of bile flow through the human choledochal sphincter following exploration of the common bile duct

The opening pressure and flow rates through the sphincter of Oddi using the patient's own bile to prime the system were measured daily in 17 patients after cholecystectomy and exploration of the common bile duct. The sequential changes in these parameters were correlated with preoperative serum bilirubin, bile bacteriology, biliary lipid composition, and bile viscosity. The opening pressure fell from an initial value of 17.2 +/- 1.9 to 9.1 +/- 0.9 cm bile (p less than 0.01) on the seventh postoperative day, indicating a self-limiting hold-up following stone extraction. The low opening pressure after the fifth to sixth day is well below the maximal hepatic secretory pressure and suggests that the bile flow into the duodenum may be continuous after cholecystectomy. The flow rate through the sphincter measured at a fixed pressure head of 30 cm of bile increased from 23.9 +/- 3.9 to 40.0 +/- 6.1 ml during the same period (p less than 0.01). Presumably, the latter represents the maximal flow rate of bile through the sphincter of Oddi under physiological conditions. These changes in flow could not be explained by alterations in the bile viscosity during the study period. The increase in flow rate was significant only in the nonjaundiced group and correlated positively with the phospholipid concentration in the bile. There were no significant differences in opening pressure, flow rates, and biliary lipid concentrations between patients with sterile bile and those with positive bile cultures.