Dramatic decline in anaesthetic mortality rates over past 50 years

Research from Dr. Daniel Bainbridge and colleagues in Western's Department of Anaesthesia and Perioperative Medicine has shown that survival rates after a general anaesthetic and within 48 hours of surgery have dramatically improved worldwide over the past 50 years. His research is published in the high-profile journal, The Lancet.

The researchers used data from 87 studies spanning back to the 1930s to analyse trends in death due to anaesthesia and soon after surgery involving more than 21.4 million anaesthetics given in countries around the world. Despite operating on more patients considered high-risk or who need more complicated surgeries now than in the past, the likelihood of dying after a general anaesthetic has dropped by roughly 90%- from an estimated 357 per million before the 1970s to 34 per million in the 1990s-2000s. During the same period, the risk of dying from any cause within 48 hours of surgery (perioperative mortality) has decreased by about 88%- from an estimated 10 603 per million before the 1970s to 1176 per million in the 1990s-2000s.

Dr. Bainbridge, an associate professor at Western's Schulich School of Medicine & Dentistry and a scientist with Lawson Health Research Institute, says the dramatic decline is due to several factors including better equipment in the O-R, better recognition and treatment of patient disease, safe surgical checklists, and better hospital infrastructure. Dr. Janet Martin, Dr. Davy Cheng and Dr. Miguel Arango were also involved in the study.

"Although this declining pattern was evident in both developing and developed nations, the greatest and most progressive decline has been in developed countries. Overall rates of perioperative and anaesthetic-related mortality have consistently been much higher in developing countries and remain two to three time higher than in developed nations"*, explains Dr. Bainbridge. He says evidence-based interventions need to be put into practice to reduce the disparities between high-income and low-income countries.

"Although anaesthetic mortality remains low compared with traffic fatalities or suicide, it still remains high compared with death caused by air travel, which is a commonly used yardstick to benchmark the risk of anaesthesia."

Dr. Bainbridge adds, "we know people are afraid of flying because of the risk of death even though that risk is low, and has been steadily going down. We also know people who come in for surgery are afraid of dying from the anaesthetic or from the surgery, and we're able to show the same thing, that the rates have been steadily going down and the risk is extremely low." Still he says, there's room for improvement. "Even though we know the risk is low, we continue to improve the standards and the safety for patients so they can be more comfortable and confident when they come for surgery."

Click here for video of Dr. Bainbridge describing his research.