Normobaric oxygen therapy strategies in the treatment of postcraniotomy pneumocephalus

Abstract

Object. Postsurgical pneumocephalus is an unavoidable sequela of craniotomy. Sufficiently large volumes of intracranial air can cause headaches, lethargy, and neurological deficits. Supplemental O2 to increase the rate of absorption of intracranial air is a common but unsubstantiated neurosurgical practice. To the authors' knowledge, this is the first prospective study to examine the efficacy of this therapy and its effect on the rate of pneumocephalus absorption. Methods. Thirteen patients with postoperative pneumocephalus that was estimated to be ≥ 30 ml were alternately assigned to breathe 100% O2 using a nonrebreather mask (treatment group) or to breathe room air (control group) for 24 hours. Head computed tomography (CT) scans without contrast enhancement were obtained at the beginning and end of treatment or control therapy. A neuroradiologist blinded to the type of treatment used software to calculate the 3D volume of the pneumocephalus from the CT scans. The percentage of pneumocephalus absorption was calculated for each study participant. Results. There was no statistically significant difference between the treatment and control groups regarding the mean initial pneumocephalus volume or time interval between CT scans. There was a significant difference (p = 0.009) between the mean rate of pneumocephalus volume reduction in the treatment (65%) and control groups (31%) per 24 hours. No patient suffered adverse effects related to treatment. Conclusions. Administration of postsurgical supplemental O2 through a nonrebreather mask significantly increases the absorption rate of postcraniotomy pneumocephalus as compared with breathing room air.