Scientists trying to develop new anaesthetics that reduce risk of memory loss
- From: Herald Sun
- May 07, 2014
SCIENTISTS are racing to develop a new generation of anaesthetics amid revelations one in 10 major surgery patients suffers long-term memory loss.
Prof Beverly Orser from the University of Toronto said the chance of cognitive impairment followed all types of surgery, but risk grew the longer an operation lasted, the deeper an anaesthetic was and the age of the patient.
While the biggest danger of permanent memory loss faces the elderly, US authorities have launched a large study into the high rates of learning difficulties among children who have undergone repeated anaesthetics.
“Roughly one in three patients show a decline in cognitive dysfunction at the time of hospital discharge, one in 10 show a deficit that persists at three months,” Prof Orser today told the Australian and New Zealand College of Anaesthetists annual meeting in Singapore.
“It’s a big problem, the incidents are high, but unfortunately we don’t have a real clear insight into the underlying mechanisms and no treatment.”
After finding the activity of a receptor in the brain associated with memory called a5GABAa increased following anaesthetic, Prof Orser’s Canadian team developed a new drug to block the receptor and were able to prevent the long-term memory loss suffered by anaesthetised mice.
But while the development of new generation anaesthetic drugs are in the early stages, Prof Orser warned that patients needed to be better informed of the risk and better monitored for memory loss.
Assoc Prof Lis Evered from Melbourne’s St Vincent’s Hospital said that while the jury is still out on whether it is the anaesthetic or actual surgery that is causing cognitive problems after an operation, it was a growing concern that has to be addressed.
Assoc Prof Evered released research showing a third of patients over 65 experiencing temporary memory issues after surgery go on to suffer dementia within seven-and-a-half years — compared with just 10 per cent in the general population.
“There is a proportion who actually don’t recover to their preoperative level of cognition,” Assoc Prof Evered said.
Grant McArthur is attending the Singapore conference as a guest of ANZCA.Originally published as Race to develop new surgery drugs