The rationale for perioperative brain protection

Perioperative brain protection refers to prophylactic measures instituted during the perioperative period to prevent or reduce ischaemic damage and to improve neurological outcome. In that context, strategies for protecting the brain rely on the control of physiological variables, anaesthesia, administration of non-anaesthetic pharmacological agents and preconditioning. Avoiding hyperthermia, hyperglycaemia and arterial hypotension are passive neuroprotective measures acknowledged in human beings. The protective effect of anaesthesia, compared to the awake state, is demonstrated in animals but remains to be validated in clinical practice. Laboratory studies investigating pharmacological neuroprotection have shown interesting results but most clinical trials have been disappointing except for a few drugs in specific settings. Preconditioning which results in the induction of some resistance to ischaemia appears as a promising strategy. Up to now, the translation of beneficial experimental results into clinical success is considered an entirely permissible hope but remains an unachieved objective.