The pattern of leucocyte response to surgical trauma in the African Negro.

The leucocyte response to surgical trauma in the Nigerian Negro is investigated. The surgical operations were graded, according to the degree of anticipated tissue trauma, into minor, intermediate and major, in 66 patients (27 males and 39 females) who had elective surgical operations with no sign of infection. The peripheral blood total and differential leucocyte counts were determined pre-operatively and at 2 h, 24 h, and 7 days postoperatively. A highly significant increase (P less than 0.001) in the total leucocyte, polymorphonuclear leucocyte (PMN) and stab cell counts occurred 2 h and 24 h after major surgery. These changes persisted for 7 days after major surgery except for the stab cell count which was by then no longer significantly raised. Similarly, highly significant increases occurred in the total and PMN counts 2 h and 24 h after intermediate surgery. The increases were not significant by the 7th postoperative day. There was a decrease in the lymphocyte counts after major surgery which was not significant at 2 h but was just significant (P less than 0.05) 24 h postoperatively. There was a return to the pre-operative level by the 7th postoperative day. There were no significant changes in the leucocyte counts after minor surgery or in the monocyte, eosinophil and basophil counts after intermediate or major surgery. Despite lower pre-operative total leucocyte (WBC) and PMN counts found in this study, the total leucocyte and PMN response to surgical trauma in the Nigerian Negro is similar to previous observations made in the Caucasian. The response of lymphocytes in the Nigerian Negro, however, differs from that reported in the Caucasian and demands further study.