Anaesthetic depth and surgical outcomes

A landmark anaesthesia trial (the Balanced Anaesthesia Study) has been published in the prestigious general medical journal The Lancet.

L-R: Dr Doug Campbell (Chief Investigator, Auckland), Professor Kate Leslie AO FAHMS (Chief Investigator, Melbourne) and Professor Timothy Short (Principal investigator, Auckland).
L-R: Dr Doug Campbell (Chief Investigator, Auckland), Professor Kate Leslie AO FAHMS (Chief Investigator, Melbourne) and Professor Timothy Short (Principal investigator, Auckland)

This international study was undertaken in 78 centres in eight countries, including all the major teaching hospitals associated with the University of Melbourne.

Deep general anaesthesia was associated with worse outcomes than light general anaesthesia in observational studies, but until Balanced no large randomised controlled trials had been undertaken.

The study included 6,640 patients who were aged 60 years and over, with significant co-morbidity, randomised them to deep or light general anaesthesia and followed them for one year.

Mortality was similar in the two groups (7.2% in the deep group versus 6.5% in the light group).

There were no differences in any of the secondary outcomes, and there was only one case of awareness during anaesthesia.

Senior author Professor Kate Leslie AO FAHMS, Centre for Integrated Critical Care Medicine, said: "This brings to fruition 10 years of intense effort by the study team and the ANZCA Clinical Trials Network".

"These results are great news, because they show that deep anaesthesia is safe and can be used if indicated for individual patients," she said.

"They are also another example of the power of collaboration in delivering evidence that guides care and helps in improves patients' lives."

For more information https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(19)32315-3/fulltext.