Michael Avidan, George Mashour and David Glick highlight the serious issue of awareness during anaesthesia in a recent review published by F1000 Medicine Reports.

Consciousness during general anaesthesia is an extremely distressing condition leading to post-operative psychological trauma and contributes towards patients' fear of surgery. Dr Avidan, a member of Faculty of 1000 Medicine and a leading authority on Anaesthesia and Pain Management, writes that intra-operative awareness with subsequent recall is surprisingly common, affecting around 1 in 500 surgical cases. These appear to be mostly preventable.

There are currently a number of candidate awareness monitors available to anaesthesiologists and theatre staff, but attention has focussed on the bispectral index (BIS) monitor, which is used widely in operating rooms and intensive care units around the world. However, it is not clear that the reduction in awareness reported with BIS monitors is attributable predominantly to the technology itself. Controversially, recent research suggests that previous cases of awareness with explicit recall might have been prevented by implementing a simple 'increased vigilance' protocol. Such a protocol would cost less and be less prone to machine malfunction.

Large, prospective randomized trials are currently underway to evaluate effective awareness monitoring technologies, with the aim of ultimately improving intra-operative patient care. Avidan says, "Cost effective interventions that increase vigilance should be implemented to decrease the likelihood of this complication."