Cerebral Metabolism During Air Transport of Patients After Surgery for Malignant Glioma

Abstract

Post-operative air transport of patients following an intracranial procedure is not uncommon. The transport itself may pose a risk, and if there are harmful effects to the brain this should be reflected in the brain metabolism. The aim of this study was to analyze possible alterations in cerebral metabolism that could be caused by air transport. Four patients with glioblastomas were operated with a biopsy or a craniotomy. During this procedure microdialysis catheters were placed in tumor tissue or brain adjacent to tumor and in normal cerebral tissue. In this study we have analyzed cerebral glucose metabolites (glucose, lactate / pyruvate ratio), glycerol, and glutamate at five time points during a 24-h period including air transport. Analyzing mean values, there was a small but significant increase in the lactate/pyruvate ratio from 45.18 to 47.78 in normal cerebral tissue after air transport compared to a previous fasting sample. For tumor tissue there was a small decrease in glucose from 1.04 to 0.92 mmol L(-1) and an increase in glutamate from 13.08 to 19.06 micromol L(-1). There were no other significant differences in the analyzed cerebral metabolites after air transport. There were only minor differences in levels of cerebral metabolites after air transport compared to a previous fasting sample. Thus it seems that air transportation of the four reported patients did not cause any major cellular damage or metabolic changes as assessed by extracellular glucose, lactate/pyruvate ratio, glycerol, or glutamate.