Declines in serum free and bound choline concentrations in humans after three different types of major surgery.

We examined the changes in circulating choline status in humans in response to major surgery by measuring serum free and phospholipid-bound choline concentrations before, during and 1-72 h after total abdominal hysterectomy, off-pump coronary artery graft surgery or brain tumor surgery. Preoperatively, the mean serum free and phospholipid-bound choline concentrations in patients scheduled for abdominal hysterectomy (n = 26), off-pump coronary artery grafting surgery (n = 34) or brain tumor surgery (n = 24) were 12.3 +/- 0.5, 12.1 +/- 0.4 and 11.4 +/- 0.4 micromol/l, and 2495 +/- 75, 2590 +/- 115 and 2625 +/- 80 micromol/l, respectively. Serum free choline and phospholipid-bound choline concentrations decreased from these baseline values to 8.8 +/- 0.7 (p < 0.001), 8.8 +/- 0.5 (p < 0.001) and 8.2 +/- 0.4 micromol/l (p < 0.001), and 2050 +/- 108 (p < 0.001), 2166 +/- 59 (p < 0.001) and 1884 +/- 104 micromol/l (p < 0.001) at 1 h after hysterectomy, off-pump bypass graft surgery or brain tumor surgery, respectively. They remained at these low levels for 24 h and then gradually increased towards the preoperative values at 48-72 h postoperatively. Serum cortisol increased postoperatively in all surgical patients for 24 h and its levels were inversely correlated with serum free and bound choline concentrations. These results show that circulating free and bound choline concentrations decrease for 72 h after total abdominal hysterectomy, off-pump coronary artery graft surgery or brain tumor surgery in humans.