However, Professor Paul Myles believes nitrous oxide - also known as laughing gas - could help people living with depression.

On Sunday Professor Myles was the guest speaker at the eighth annual William Pugh Memorial Lecture.

The visit came more than 170 years after Dr Pugh completed the first successful anaesthesia for a surgical operation in Australia, in Launceston in 1847.

Professor Myles is making history in his own right as a leading researcher with more than 300 published articles and $35 million in medical research grants.

With a focus on patient recovery and post-operative complications, he said the value of anaesthesia could not be overstated.

"The discovery of general anaesthesia is often described as the most important discovery in all society, certainly in all of medicine," he said.

"When you think about what happens now. How many people have surgery, for so many conditions that literally would not be possible without anaesthesia."

In his presentation, A Vexed History of Laughing Gas: A Cycle out of Depression, professor Myles shared the tragic history of nitrous oxide.

This included the man credited with pioneering the use of anaesthesia in dentistry, Horace Wells, who died by suicide in 1848.

Through his research at Melbourne's Alfred Hospital as director of anaesthesia and perioperative medicine, Professor Myles is leading an Australian-first study into the use of nitrous oxide as a treatment for depression.

The trial involves more than 180 patients living with severe depression, where standard therapies have failed.

If the treatment proves successful, Professor Myles said an incredible burden could be lifted.

"Depression is one of the biggest causes of disability in our society," he said.

"It leads to misery for the person and their family. Suicide in particular is perhaps one of the greatest tragedies.

"Horace Wells' life ended in depression. I am hoping we can now turn that around."

The lecture was facilitated by the Queen Victoria Museum and the Launceston General Hospital Historical Committee.

Convenor Dr John Paull, a retired anaesthetist who first met Professor Myles in 1988, said he had become a legendary figure in Australian anaesthetic research.

"One of his [Professor Myles] particular skills, I think, is to identify the things we always assumed were working in a certain way, and to question whether that is true or just something we have grown up with," Dr Paull said.

"Then, to work out ways in which that can be tested."