Neutrophil Chemotaxis During Halothane and Halothane-N2O Anesthesia in Man

Abstract

Polymorphonuclear neutrophil (PMN) function was evaluated in 21 adult male volunteers anesthetized with 0.8, 1.2, or 1.6% halothane-O2, and halothane-O2 plus 20% N2O and 60% N2O. Variables measured included PMN chemotactic index (CI), PMN random migration (RM), and total leukocyte (WBC) and PMN counts. Halothane significantly (p<0.025) increased WBC and PMN counts and caused a concentration-dependent decrease in PMN CI and RM. Addition of 20% N2O did not change any variable; however, adding 60% N2O increased (p<0.05), PMN CI during 1.2 and 1.6% halothane and RM during 1.6% halothane. Termination of N2O reduced CI back to halothane-O2 levels in those receiving 1.2 and 1.6% of the anesthetic but did not significantly alter any other variable. PMN CI and RM remained decreased and WBC and PMN remained elevated during the first 2 postanesthetic hours. WBC and PMN counts were still significantly (p<0.01) elevated the day after anesthesia in the group receiving 1.6% halothane. All other variables returned to control levels 24 hours after anesthesia. These data demonstrate that halothane produces a concentration-dependent reduction in PMN CI which can be partially reversed with the addition of N2O, and suggest that halothane anesthesia may increase susceptibility to bacterial infection by reducing PMN migration toward invading organisms.