The Effects of Nitrous oxide in neuroanaesthesia has been questioned many times due to its detrimental effects on the cerebral vasculature and the brain tissue. However, there are no large-scale outcome studies to approve or disapprove its continued use in neuroanaesthesia.
Nitrous oxide has been used in neuroanaesthesia for many years. Intraoperative analgesia with haemodynamic stability apart from the ability to rapidly alter the anaesthetic depth are the prime advantages of this agent.
The main disadvantage of Effects of Nitrous oxide in neuroanaesthesia is an increase in the cerebral blood flow owing to an increase in the cerebral metabolism, a direct effect of nitrous oxide. In intact cerebral autoregulation, any increase in blood flow is intrinsically compensated to maintain intracranial pressure.
The Effects of Nitrous oxide in neuroanaesthesia on cerebral autoregulation when used with other anaesthetic agents is also unsettled. Bedforth et al found that 50% N20 impaired auto-regulation when administered with 1 MAC sevoflurane whereas the autoregulation was preserved when 50% N2O was added to 1.5 MAC sevoflurane. Effects of Nitrous oxide did not include the strength of cerebral autoregulation during propofol anaesthesia. However, when administered by itself, Effects of Nitrous oxide produces significant impaired autoregulation.
In situations of reduced intracranial compliance, if autoregulation were impaired the intracranial pressure would rise and compromise cerebral perfusion. This may be detrimental in neurosurgical procedures. Since CO2 reactivity is preserved when N2O is used with propofol or inhalational agents, it may be argued that the increase in cerebral blood flow can be countered by instituting hypocapnia.
The Effects of Nitrous oxide on the susceptibility of human brain tissue to ischaemia is unclear. Animal studies have documented deleterious effects of nitrous oxide, though there are no human studies on this aspect. Thus, the continued use of N2O in neurosurgical practice is a matter of ongoing debate