Towards zero carbon healthcare: anaesthesia
Cliff Shelton, Rebecca Knagg, Rakesh V. Sondekoppam, Forbes McGain
Abstract
What you need to know• Sevoflurane and isoflurane have smaller atmospheric impacts than desflurane and nitrous oxide • Intravenous anaesthetic agents have minimal atmospheric impacts, but drug waste and urinary excretion of drugs and metabolites causes pollution in soil and ground water • Nitrous oxide is a common cause of medication waste and greenhouse gas emissions due to leaks in supply systems, over-ordering, and unused gas in cylinders returned to suppliers being vented to the atmosphere Case 1-A 30 year old woman attends the obstetric anaesthetic clinic at 36 weeks' gestation.This is her first pregnancy.The baby was in the breech position, and, after an unsuccessful attempt to turn the baby, she has been offered the option of planning for a vaginal delivery or a caesarean section.The anaesthetist discusses the anaesthetic and analgesic options for both and reassures the patient that all options appropriate to the mode of delivery are safe.Her priority is a safe delivery but she recently read online that both anaesthetic agents and "gas and air" contribute to global warming.Concern about the world in which her child will grow prompts her to ask which is the "greenest" option.Case 2-A 55 year old man is listed for total knee replacement for osteoarthritis, which is limiting his mobility and affecting his ability to pursue his passion for fell walking.When offered a choice of spinal or general anaesthesia, he says he has no preference providing both are safe, but he has noticed the enormity of hospital waste and asks which is the most sustainable option.Providing anaesthesia for approximately 310 million surgical procedures worldwide every year, 1 and contributing to peri-operative medicine, critical care, and pain management, generates emissions of greenhouse gases (GHGs) and vast amounts of waste.In this paper, we suggest ways that anaesthesia teams can mitigate their environmental footprints while integrating their primary aim of providing safe, high quality patient care. What is the evidence?Life cycle assessments of the "carbon footprints" of anaesthetic equipment, medications, and procedures, 2 3 global endorsement of sustainable anaesthesia practice, 4 and expanding literature on the atmospheric effects of inhalational anaesthetics 5 -8 show the problem; however, strong evidence for specific solutions is relatively sparse and novel compared with other aspects of healthcare. 4 9 10MAC=minimum alveolar concentration; the mean percentage end-tidal anaesthetic agent concentration at which a patient of 40 will be unresponsive to surgical stimulation