[Effect of intraoperative blood loss on the function of natural killer cells in tumors of the upper gastrointestinal tract].

The activity of natural killer cells was measured perioperatively in 39 patients with esophageal and gastric cancer and was correlated with intraoperative blood loss. The activity of natural killer cells in all patients sank significantly (p < 0.05) on the fourth postoperative day to their original values. In the 24 patients with an intraoperative blood loss of more than 700 ml, the activity of the natural killer cells decreased significantly (p < 0.05) on the fourth postoperative day, in contrast to those 15 patients with an intraoperative blood loss of less than 500 ml; intraoperative blood loss and activity of natural killer cells show a correlation of R2 0.82.