Surgical stress and its effects on serum cholesterol

Serum cholesterol determinations were performed on 20 patients before and after various surgical procedures. All 20 patients had a decrease in serum cholesterol concentration postoperatively. The average maximal decrease in cholesterol was 60 mg. per 100 ml. and occurred on the first or second day following surgery. In 3 of 5 patients in whom hourly serum cholesterol determinations were done during surgery, there appeared an initial slight elevation of cholesterol which was followed with the expected postoperative decrease. Two other patients who also had hourly cholesterol determinations had slightly lower concentrations during surgery than the preoperative control value. All 5 of these patients had the expected more marked decrease in serum cholesterol one or two days later. The effect of the postoperative regimen of intravenous feeding with 5 percent dextrose in water and saline solutions upon serum cholesterol was studied in five control patients. This dietary regimen, which was similar to postoperative regimen on the other patients studied, did not produce a significant decrease in serum cholesterol concentration. Some of the factors and mechanisms which may contribute to the observed postoperative decrease in cholesterol concentrations have been briefly discussed.