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Henning Ruben

BMJ 2005; 330 doi: (Published 06 January 2005) Cite this as: BMJ 2005;330:97

Anaesthetist who invented the Ruben valve and the Ambu self-inflating bag

By any standards, Henning Ruben was a remarkable man. During his career he was, at various times, a member of the Danish fencing team, a professional dancer, magician, thought reader, dentist, doctor, and inventor. To these might be added his reputation as a bon viveur and raconteur par excellence. It was, however, for his skill and originality as an inventor that he was best known.

He was born in Copenhagen in 1914, the eldest son of an orthodox Jewish family. At 19 he entered the Royal Dental College in Copenhagen, combining his studies with the exercise of his other talents. With a well known singer, he toured the halls as a professional dancer, excelling at the tango. He was also an accomplished athlete, becoming a member of the Danish fencing team that won a bronze medal at the world championships in Monte Carlo in 1939. He became a member of the Danish Magic Circle.

In 1943 he enrolled as a medical student at the University of Copenhagen. But after the Nazi occupation of Denmark, he had to leave the country urgently. One night he escaped on a fishing boat bound for Sweden, where he remained for two years, working as a dentist in Stockholm, as well as employing his talents as a magician and thought reader. He returned to Denmark in 1945 and graduated in medicine in 1946.

At that time, anaesthesia was an undeveloped specialty in Denmark but was more advanced in Sweden, where Ruben found the combination of physiology, pharmacology, and physics of great interest. He decided to become an anaesthetist, but in the early years after the war, travel was difficult. However, in 1947 he was invited to Sweden by the Swedish Society of Illusionists and, at their meeting in Stockholm, he performed brilliantly to a packed concert hall. During that visit, he introduced himself to the anaesthetists at Sabbatsberg Hospital and St Ericks Hospital. As a result, the following year he was appointed to the Serafimerlasarettet Hospital in Stockholm. He returned to Copenhagen in 1949 and was appointed to the Gentofte Hospital and, later, to the Finsen Institute.

Eager to broaden his experience, in 1951 he negotiated a six month secondment to the University of Iowa to work with the anaesthesiologist Lucien Morris. It was in Iowa that he met the anaesthesiologist James Elam with whom he began a collaboration that lasted until both had retired.

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Back in Copenhagen, he was appointed head of department at the Finsen Institute in 1953. There he began his programme of research and invention that was to have a lasting effect on the practice of anaesthesia and resuscitation. In 1953 he developed a lightweight, foot-operated sucker. This played a significant part in other developments for, in addition to its intrinsic value, it brought Ruben into contact with Dr Holger Hesse, the founder of the company Ambu-Testa. The foot-operated sucker, although first marketed by Ambu, was soon copied by other manufacturers. But this was only the start.

The following year Ruben described and published a simple automatic constant-rate syringe pump for the controlled delivery of drugs. It was driven by a wind-up alarm clock. However, as early as 1948, he had seen a non-rebreathing valve in an American anaesthetic journal. Unable to acquire it quickly, he attempted to make a copy, but misinterpreted the drawing. Entirely by chance, he introduced some changes that led, with the help of a watchmaker, to the development of his own non-rebreathing valve—the “Ruben valve”—which made him a household name among anaesthetists round the world. By 1982, over a million Ruben valves had been made.

Curiously, it was a strike by Danish truck drivers in 1954 that led to the development of the self-inflating bag. Lorries delivering oxygen were kept off the road and oxygen supplies in Danish hospitals ran low. Ruben got a mechanic to weld together four bicycle wheel spokes and then manipulated the spokes into an anaesthesia bag. He described how, with the aid of an attached string, he obtained a globe-shaped frame, which kept the bag expanded. When compression of the bag was released, the spokes regained their curved shape, making the bag self-filling. With his non-rebreathing valve and a valved inlet, the self-inflating bag was born and copied all over the world. In 1964 the American Medical Association declared the self-inflating bag to be among the most significant medical advances in anaesthesia of the previous 25 years.

In 1957 training in resuscitation (mouth to mouth) became mandatory in many schools in Scandinavia. In the same year Ruben constructed the first manikin on which people could be trained in the correct use of the self-inflating bag. Six months later, when mouth to mouth ventilation had become widely accepted, the manikin was in great demand for training. In addition to many medical meetings, it was demonstrated at an international NATO meeting in Copenhagen.

Ruben leaves a wife, Vera; four children; and seven grandchildren.

Henning Ruben, professor of anaesthesia University of Copenhagen 1955-84 (b 1914; q Copenhagen 1946), d 4 December 2004.

John Zorab


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