DEFORMABILITY AND OXIDANT STRESS IN RED-BLOOD-CELLS UNDER THE INFLUENCE OF HALOTHANE AND ISOFLURANE ANESTHESIA

1. The effects of halothane and isoflurane anesthesia on red blood cel l (RBC) deformability, lipid peroxidation and antioxidant enzymes were tested in rabbits. 2. RBC transit time was significantly increased to 2.12+/-0.07 msec after 1-hr halothane anesthesia preceded by 6 mg/kg pentobarbital injections from 1.98+/-0.07 msec preanesthesia value (p< 0.05). Thiobarbituric acid-reactive substances also were increased sig nificantly, being 23.35+/-2.75 nmol/gHb and 33.11+/-5.34 nmol/gHb befo re and after anesthesia, respectively (p<0.05). 3. Under halothane ane sthesia without prior pentobarbital injection or under isoflurane anes thesia with or without pentobarbital injection, no significant alterat ions were observed in these parameters. 4. RBC superoxide dismutase ac tivity was decreased in the group anesthetized with the pentobarbital- halothane combination. The impaired RBC deformability and increased ox idant damage might be related to the free radical formation during the metabolism of halothane. Pentobarbital can potentiate this effect eit her by inducing cytochrome P-450 or by altering antioxidant defense. 5 . Alterations in RBC mechanical properties may contribute to the tissu e perfusion problems that develop after surgery under general anesthes ia. (C) 1998 Elsevier Science Inc.