8th Pugh Lecture Sunday 16 June 2019

Launceston General Hospital

Launceston General Hospital Historical Committee in conjunction with the Launceston Historical Society 8th Pugh Lecture Sunday 16 June 2019

Prof. Paul Myles A vexed history of laughing gas: A cycle out of depression

The eighth Pugh day lecture was delivered on Sunday, 16 June to an audience of over 80 members and guests of the Launceston Historical Society. On Monday, 7 June 1847 Dr William Pugh performed a surgical operation on a patient under the influence of ether, for the first time in Australia in his private hospital in Launceston.

Marion Sargent, president of the Launceston Historical Society welcomed guests and Dr John Paull, convener of the Pugh Day lecture introduced Professor Paul Myles, who was the eighth Pugh day lecturer. Paul is Professor and Director of the Department of Anaesthesiology and Perioperative Medicine at the Alfred Hospital in Melbourne, and at Monash University, Australia. He is an Australian National Health and Medical Research Council Practitioner Fellow, and Fellow of the Australian Academy of Health and Medical Science; an Editor of the British Journal of Anaesthesia and an Editorial Consultant for The Lancet. He has published more than 300 articles, and been awarded more than 25 NHMRC grants totalling more than $35 million. The main focus of his research has been on patient quality of recovery, avoidance of postoperative complications, and large multicentre trials in perioperative medicine. In 2017 he received the Excellence in Research Award from the American Society of Anesthesiologists.

Prof Myles reviewed the early history of the discovery of nitrous oxide, its use in stage shows, dentistry and the role of Horace Wells in popularising its use in dentistry and surgery. He also told the story of Horace’s tragic death and said that in his opinion Wells deserved recognition for his role in establishing nitrous oxide as an anaesthetic agent.

The early users of nitrous oxide did not appreciate that if inhaled without air or oxygen it would prove rapidly fatal and a number of patients died because of this misunderstanding. Once ether and chloroform were introduced as anaesthetic agents in 1846 and 1847 respectively, it became customary to administer safe concentrations of nitrous oxide as part of the anaesthetic.

Whilst the use of nitrous oxide appeared to be very safe concerns began to arise that its long-term use could lead to disability and death because of its effects on haematopoiesis. In 2014. Paul and five other colleagues published a report based on an analysis of 138 abstracts selected from more than 8000 Journal abstracts. The conclusion was that at that time, scientists did not have robust evidence for how nitrous oxide used as part of general anaesthesia affected mortality and cardiovascular complications.

Over a number of years Paul and multiple other researchers reported the results of the large ENIGMA trial and its successor ENIGMA II which attempted to identify adverse effects of nitrous oxide use during general anaesthesia. One conclusion was that nitrous oxide was safe to use in non-cardiac surgical patients.

Paul concluded with the astonishing information that inhaling nitrous oxide in safe concentrations resulted in a reduction of depressing symptoms in psychiatric patients.

Deanna Ellis, President of the Launceston General Hospital Historical Committee invited questions from the audience, to which Paul responded. Marion Sargent presented Paul bottle of Tasmanian wine and a hard cover, signed and numbered copy of Dr Paull’s annotated transcription of Dr Pugh’s diary of his 1835 four month voyage from England to van Diemen’s Land, long thought to have been lost.

Dr John D. Paull
LGH Historical Committee

Paul Myles is Professor and Director of the Department of Anaesthesiology and Perioperative Medicine at the Alfred Hospital in Melbourne, and at Monash University, Australia. He is an Australian National Health and Medical Research Council Practitioner Fellow, and Fellow of the Australian Academy of Health and Medical Science; an Editor of the British Journal of Anaesthesia and an Editorial Consultant for The Lancet

He has published more than 300 articles, and been awarded more than 25 NHMRC grants totalling more than $35 million. The main focus of his research has been on patient quality of recovery, avoidance of postoperative complications, and large multicentre trials in perioperative medicine. In 2017 he received the Excellence in Research Award from the American Society of Anesthesiologists.