[T4 and T8 lymphocytic populations after total hip replacement]

Immunosuppression is involved in the occurrence of sepsis after surgical trauma. A postoperative lymphocytopenia is a recognised fact. In the opposite, studies on T-lymphocytes helpers (CD 4) and suppressors (CD 8) resulted in conflicting results. The aim of this study was to assess the variations in these two T-lymphocyte sub-populations using strongly standardized conditions in order to minimize the risk of non specific variations: same surgeon, same surgical technique, blood samples collected just before induction, immediately and 24 hours after surgery, automatized measures (Technicon H1). The results confirmed the lymphocytopenia, 24 hours after surgery, but no differences on CD 4 and CD 8 percentages were noted. It is concluded that during the first 24 postoperative hours surgery does not change the relative proportions of T-helpers and T-suppressors. Their measurement is not more useful than total lymphocyte count for assessment of postoperative immunosuppression.