Monooctanoin dissolution of retained biliary stones in high risk patients

Monooctanoin, a cholesterol solvent, was infused into the biliary tracts of six high risk patients, in an attempt to dissolve retained stones. The infusion rate was constant, 5-10 ml/h. The mean age of the patients was 76 years. Associated medical conditions were primarily cardiac in nature. Duration of infusion averaged 6 days. In two patients, the stones were completely dissolved. One patient was reoperated despite the stones appearing smaller after 6 days of infusion. At surgery, no stones were found. Two patients in whom dissolution was unsuccessful underwent reoperation. In both, retrieved stones were composed of less than 5% cholesterol. Five of the six patients experienced at least one episode of mild abdominal pain and vomiting. None developed cholangitis, pancreatitis, or significant biochemical abnormalities. Two of the three who underwent reoperation tolerated it without difficulty. While mechanical extraction, when feasible, is still the treatment of choice for retained biliary stones, chemical dissolution should be attempted before undertaking reoperation.