Geoffrey Dawes was internationally respected for his work in foetal and neonatal physiology. The youngest son of the vicar of Mackworth in Derbyshire, he was educated at Repton. He retained a strong attachment to the school, serving as chairman of the board of governors for many years. He went up to Oxford where he gained a first class degree in physiology just as the Second World War began. In 1943 he completed his clinical medical training in Oxford, but was rejected for military service because of asthma. Instead he joined the department of pharmacology under J H Burn and helped to develop drugs for treating gas gangrene and for countering nerve gas exposure. At the end of the war he held a Rockefeller travelling fellowship, working at Harvard and in Philadelphia. He returned to Oxford on a Foulerton Royal Society research fellowship and continued his interests in reflexes from the heart and lungs.

In 1948 he became the first, and as it transpired, the only, director of the newly formed Nuffield Institute for Medical Research in Oxford where he worked for the next 37 years. The Institute was one of the many results of Lord Nuffield's benefactions to the Oxford Medical School. Dawes assembled an energetic and productive team of physiologists, pharmacologists and clinicians to investigate foetal physiology, in the first instance to focus on the mechanisms which controlled foetal circulation.

There followed many investigations into the distribution and control of foetal circulation predominately in unborn lambs. The influence of chemoreceptors, the mechanisms that triggered the dramatic changes of birth, in particular the control of the onset of breathing, were analysed in detail with constant attention to the implications for human physiology. He was one of the first to observe that the foetal lamb had sleep cycles as well as breathing movements in utero, and within a short time could confirm that the human foetus also slept in cycles. This naturally led to considerations of central nervous control, not only in relation to sleep state, but also heart rate variability and responses to the stimulation of chemoreceptors.

A long serving fellow of Worcester College, he became a fellow of the Royal Society, served on the editorial board of the British Journal of Pharmacology, and received many awards recognizing the importance of his contributions. These included the James Spence medal of the British Paediatric Association, the Virginia Apgar award of the American Academy of Paediatrics, the Osier memorial medal of Oxford University and many more.

He retired in 1985, but in fact did not ‘retire’. He was immediately recruited as the first director of the Sunley Research Centre at Charing Cross Hospital. His mind continued to delight in original ideas and concepts. He was a skilled mathematician (a trait inherited from his father) and applied numerical methods to describe the complexities of human foetal heart rate patterns. His studies of the human foetus were made possible by the technology of non-invasive, Doppler ultrasound recording. He was fascinated by the need to understand the physiological mechanisms underlying the short and long term variations in the heart rate of the healthy human foetus and the ability to use changes induced by spontaneous hypoxaemia to detect foetal distress in utero and so devise a clinically useful diagnostic technique. He designed and produced a system of measurement now used at the bedside of obstetric departments around the world as the most precise non-invasive way of assessing the well-being of the human foetus. He was a familiar figure in the department of obstetrics at the John Radcliffe Hospital, participated in clinical case conferences and continued to chide his clinical colleagues for their preference for subjective impressions rather than objective numerical measurements of foetal heart rate patterns. Papers, letters, and reviews flowed from his pen. He had a terse synoptic style of writing, clear and economical. Sometimes he had to be reminded that his readers’ minds were not as quick and logical as his own and had to be persuaded to insert what he considered to be unnecessary elaboration and explanation.

He was always open to new ideas, had a precise and detailed memory and an unremitting dislike for thoughtlessness and ignorance. His encounters with the latter stimulated his asthmatic wheeziness so it was a familiar signal of his mood when he angrily had to use his inhaler. He enjoyed attending international meetings and was sought as a speaker until his final year. Of formidable intellect, great integrity and questing spirit, he was also a kind and humorous man who appreciated and helped younger scientists and enjoyed the company of like-minded scientists around the world. He was an accomplished fly fisherman. He married Margaret Monk in 1941 and they had two daughters and two sons.

C W G Redman

[The Independent, 16 May 1996; The Times, 20 May 1996]