Isoflurane and cerebrospinal fluid pressure--a study in neurosurgical patients undergoing intracranial shunt procedures.

The effect of isoflurane 1.0% and 1.5% with nitrous oxide on ventricular cerebrospinal fluid pressure was studied in 17 patients who underwent intracranial shunt procedures. Isoflurane at both concentrations caused significant increases in cerebrospinal fluid pressure during normocapnic ventilation, but these could be prevented by simultaneous hyperventilation or by the prior induction of hypocapnia. Decreases in mean arterial pressure occurred also, and resulted in a significant reduction in cerebral perfusion pressure in normocapnic patients.