Dr Mike Tunstall

Mike Tunstall, who has died aged 82, revolutionised the control of labour pains for millions of women all around the globe.

His invention of Entonox, also known as gas and air, not only transformed women’s experience of childbirth but brought comfort to countless others across the world through its use, in ambulances and accident and emergency units, to relieve the pain of acute trauma.

Although it was during a period of his work with Sir Dugald Baird, in the 1960s, that he made the groundbreaking advance in analgesia, his mission throughout his life was to alleviate pain, especially for mothers and children.

As a result, he was also responsible for developing the isolated forearm technique, allowing doctors to detect whether a patient remained aware after a general anaesthetic had been administered; a drill to be followed when intubation failed – something that could lead to maternal death – and he helped to create an anaesthetic cream for children.

Ironically, for a man who spent most of his life helping mothers and babies, he was born in a bucket – in Assam, India where his father was a tea planter.

He spent his early childhood in India, attending a kindergarten there run by his aunt before being sent to prep school in the north of England, aged seven. From there he was sent to be educated at a public school in Monmouth, where he shone academically and had an ambition to become a bacteriologist.

However that career required a medical degree and so he trained at University College Hospital, London. After qualifying he met his wife, Anne, whom he married in 1954. During his two years of National Service he served as a medical officer for two artillery regiments in Germany and in 1956 he began as a trainee in general medical practice on the Isle of Wight, a move which accommodated his career and his love of sailing.

He wanted to become a GP with anaesthetic and obstetric duties but, realising he would not be able to achieve that at the local cottage hospital, he became a registrar in anaesthetics at St Mary’s Hospital, Portsmouth. It was there that he first met renowned consultant anaesthetist Dr RJ Hamer Hodges, who encouraged his juniors to take part in his obstetric anaesthetic research, and who told Dr Tunstall: “You will make a wonderful GP, but what a waste of a brain.”

From there he went to the Middlesex Hospital, London, before returning to Portsmouth and a joint senior registrar’s post on the Portsmouth and United Oxford Hospitals’ rotation where he began his research on pre-mixed gases.

When Sir Dugald Baird, Regius Professor of Midwifery in Aberdeen, was looking for an obstetric anaesthetist to help with the delivery of quads, Dr Tunstall’s name came up. They took an immediate liking to each other and, though Dr Tunstall had never intended to stay in Aberdeen, he was promised the next consultant’s post and fell in love with the area.

He recalled: “Early on in the appointment I asked Sir Dugald if I could research the use of methoxyflurane as an inhalation analgesic in the labour ward. His reply was ‘Get on with it boy, that is what you are here for’. The freedom and the privilege of ‘getting on with it’ remained until my retirement in 1992.”

While previously nitrous oxide – a liquid – and the gas oxygen, could only be administered from four bulky cylinders – one of each plus two spares – he demonstrated that they could be mixed, creating Entonox.

He and his colleagues also established one of the world’s first neonatal intensive care units, where he developed techniques that have had an enormous impact on perinatal mortality and premature babies. He had insight, not just as a doctor but from personal experience as a father, into how vital that work was following the birth of his own precious daughter at 29 weeks, weighing just 2lbs.

Dr Tunstall, who had also been a clinical senior lecturer did not profit financially from his invention and had no interest in its commercial value. A humble man, his only motivation was the relief of pain.

Although his profession demanded long hours, he spent as much time as he could with his family and in the outdoors. He taught his three children to sail and was commodore of Aberdeen and Stonehaven Yacht Club. He also enjoyed windsurfing and beach running and took up skiing at the age of 55. He was diagnosed with leukaemia 20 years ago and had ongoing cancer problems but did not let his illness affect his love of the outdoors.

An honorary research fellow of the department of environmental and occupational medicine at Aberdeen University, he was awarded his honorary doctorate in 2006. Despite his “retirement”, it was only in the last couple of years that he stopped going into the labs where he was still working on gases.

Regarded as the most significant contributor to obstetric anaesthesia that the UK has ever produced, his own account of his career typically, and modestly, gave no hint of the importance of his innovations.

He is survived by his wife, with whom he recently celebrated their 57th wedding anniversary, his children Chris, Gareth and Amanda and six grandchildren.