Halothane, hypocapnia, and cerebrospinal fluid pressure in neurosurgery.

Abstract

Recent studies by McDowall, Jennett, Barker, and Fitch [1–4] demonstrated that halothane may increase intracranial pressure, especially in patients with intracranial space-occupying lesions, and suggested that hypocapnia may not prevent such increases. A subsequent editorial [5] concluded that halothane is relatively contraindicated for intracranial surgery. The validity of this conclusion may be questioned because in the patients studied by the McDowall group, the levels of hypocapnia were inconstant, awake cerebrospinal fluid pressure (CSFP) was not measured, and the effect of halothane was observed for only 10 min. The present study was designed to examine the effect of continuous administration of halothane on CSFP at a constant level of hypocapnia induced either before or together with the introduction of halothane. In addition, the combined effect of droperidol, fentanyl, nitrous oxide, and hypocapnia on CSFP was examined.