Morphine responders with unexplained pain after cholecystectomy may have sympathetic overactivity

In patients with unexplained pain after cholecystectomy, morphine often induces pain and may increase plasma aspartate aminotransferase activity because of exaggerated or prolonged rises in pressure within the biliary system. Previous studies have demonstrated that patients showing increases in aspartate aminotransferase have increases in plasma concentrations of noradrenaline and dopamine prior to and soon after induction of pain. The purpose...