The effect of exchange therapy on postburn lymphocyte suppression.

Circulating mediators have been implicated in the pathophysiology of postburn immunologic depression, suggesting the restorative potential of exchange therapy. Previous reports have stressed the immunosuppressive effects of massive transfusions and major surgical procedures. The effect of plasma exchange (PLA/EX) and surgical excision and grafting (E/G) procedures on postburn lymphocyte function was evaluated retrospectively in one-way mixed lymphocyte reaction assays. Twenty one adult patients with a mean total body surface area (TBSA) burn of 52.6% underwent a total of 54 PLA/EX procedures without complications. The mean volume of plasma exchanged was 5079 ml. PLA/EX was performed at a mean time of 10.4 days after burn injury. Thirty adult patients with a mean TBSA burn of 42.8% underwent a total of 78 E/G procedures. The mean graft size was 2373 cm2 per E/G procedure or 7.25% TBSA. The mean transfusion requirement per E/G was 3355 ml. The initial E/G occurred at a mean of 7.5 days after burn injury. PLA/EX decreased suppression of normal lymphocyte blastogenesis by burn serum from 62.7% to 28.3% (p less than 0.001). The mean duration of improvement in lymphocyte function was 4.8 days. Similarly, the mean suppression by burn serum drawn pre-E/G was 42.2%, while serum suppressive activity post-E/G was 29.1% (p less than 0.05). The mean duration of mixed lymphocyte reaction improvement was 5.0 days. Both PLA/EX and E/G procedures have a significant beneficial effect in restoring lymphocyte function in burn patients.