Desflurane affords greater protection than halothane against focal cerebral ischaemia in the rat

Background. We studied the potential neuroprotective effectsof halothane and desflurane, compared with the awake state,on infarct size following 2 h of intraluminal middle cerebralartery occlusion (MCAo) and 22 h of reperfusion. Methods. Male Sprague–Dawley rats were anaesthetized withdesflurane or halothane, intubated, and mechanically ventilated.Mean arterial pressure (MAP), blood gases, and pH were controlled.Body temperature was maintained at 37.5–38°C. Animalswere assigned to one of four groups according to the anaesthetictype (halothane or desflurane) and the duration of anaesthesia:‘short-duration’, during the preparation only; ‘long-duration’,during both preparation and ischaemia. Twenty-four hours afterMCAo, infarcts were visualized by staining with 2,3,5-triphenyltetrazoliumchloride. Two additional groups of rats were subjected to thesame protocol as that of long-duration halothane and long-durationdesflurane with additional pericranial temperature measurementsmade. Results. Physiological parameters were comparable between thegroups but MAP was higher (P<0.0001) in the short-durationgroups. In the short-duration groups, cerebral infarct volumeswere not significantly different between anaesthetics (short-durationhalothane: 288 (61) mm³, mean (SD); short-duration desflurane:269 (71) mm³, P>0.56). Compared with the awake state (short-durationgroups), halothane and desflurane significantly reduced infarctvolumes (long-duration halothane: 199 (54) mm³, P<0.0047vs short-duration halothane; long-duration desflurane: 121 (55)mm³, P<0.0001 vs short-duration desflurane). The mean infarctvolume in the long-duration desflurane group was significantlylower than that in the long-duration halothane group (P<0.0053).Pericranial temperatures were similar in the desflurane andhalothane long-duration groups (P>0.17). Conclusions. In rats, desflurane-induced neuroprotection againstfocal cerebral ischaemia was greater than that conferred byhalothane. Br J Anaesth 2003; 91: 390–6