We tested the hypothesis that 5 cm H2O of
positive end-expiratory pressure (PEEP) reduces the incidence of
pneumocephalus in patients who undergo spinal intradural
tumor surgery. Fifty-three ASA I to III patients who underwent thoracolumbar intradural
tumor surgery between the years 2003 and 2006 were included in this study. All patients received
propofol,
fentanyl, and
cisatracurium for induction of the
anesthesia. Maintenance was provided by
propofol infusion and,
oxygen (50%) and air (50%). Group I (n=28) did not receive PEEP whereas group II (n=25) received PEEP as 5 cm H2O. Cranial computerized tomography was taken at 8 hours after the surgery and cases were evaluated for
pneumocephalus using BAB Bs200ProP Image System software.
Pneumocephalus areas between 0.03 and 4.24 cm2 were observed in 9 patients, 8 in group I and 1 patient in group II at the 8th postoperative hour, at various localizations. There were no
neurologic findings in other patients except for 2 patients in group I who presented with
headache and mental status change. Although the
cerebrospinal fluid leakage is minimal, N2O is not used and the patients are well hydrated,
pneumocephalus with
neurologic deficits may occur in patients undergoing microsurgical spinal intradural
tumor surgery in prone position. In our study, we showed that using 5 cm H2O PEEP perioperatively reduced the risk of
pneumocephalus. However, more cases must be studied to support this hypothesis.