Effect of Intraoperative Target Control End Tidal CO2 on Postoperative Recovery in Neurosurgical procedures; a Randomized Control Trial

Abstract

Background: The long abated technique of hyperventilation is still desired by neurosurgeon in the era of end tidal CO2 monitoring in the management of neurosurgical procedure. However, its use remains controversial as there is evidence of its potential to cause cerebral ischemia attributable to vasoconstriction. It may be harmless in healthy brain, but under pathological conditions it may be harmful and worsen the neurological outcome of the patients. Therefore, we designed this study to evaluate the effect of two different range of end tidal carbon dioxide (ETCO2) by two modes of ventilation (Eu-ventilation and Hyper-ventilation) on perioperative outcome and cognitive recovery following neurosurgical procedure. Methods: Fifty adult patients with brain tumour were randomized into two groups according to computer-generated random number. In Group A, ETCO2 was maintained between range of 342 mmHg (Eucapnia group) and in Group B the ETCO2 between 262 mmHg (Hypocapnia group). Brain relaxation assessment was done during intra-operative period by four point scale. AVPU scoring system was used as indicator of mental recovery at the end of anesthesia. Results: Results revealed that the brain relaxation was almost equally maintained in both the groups. Brain relaxation assessment showed that 84% patient of group B scored grades ?2, while 80% in Group A. However all recovery parameters as accessed by AVPU score were achieved earlier in Group A as compared to Group B. Conclusion: We concluded that even in neuroanesthesia maintaining euventilation and normocarbia during perioperative period is associated with prompt return of cognitive function following extubation.