Born in 1940 into a large close-knit family, he had three elder brothers and a younger sister. After George Dixon's Grammar School and Birmingham University, where he qualified in 1963, he declared his intention to train as a paediatrician by taking the Diploma in Child Health in 1965, and within a year became a Member of the Royal College of Physicians.
In 1967 he was appointed by Professor Peter Tizard to the Paediatric Department at the Hammersmith Hospital, London. Tizard was an astute judge of intellect and character and hand-picked the brightest rising stars to join him in developing the new speciality of neonatology. Rapidly his paediatric department became renowned world-wide and in this David Baum played a major role.
Recognising the importance that biochemistry was to play in unravelling many of the unique problems of immature babies he studied at Chelsea College in the department run by his brother, Harold, for an MSc (Biochemistry). Much of his own personal research, as well as collaborative work and the studies that he later encouraged others to do, stemmed from this wider understanding of basic science.
In 1968 he invented a heat-preserving foil sheet - the "Silver Swaddler" - used to this day to protect vulnerable premature babies immediately after birth from the devastatingly detrimental effects of rapid heat loss. Within a short time he also perfected skills to study the retinae of the tiniest babies and then, in 1969, went to the University of Colorado in Denver, on the first of many visiting professorships. There he carried out a ground- breaking follow-up study of teenagers blinded in the 1950s by the scourge of oxygen toxicity.
While in Denver, as later in Oxford and Bristol, he and his wife, Angela, an artist, enlarged their already considerable circle of friends. Their generous hospitality and delight in social gatherings ensured that a party at the Baums' was an occasion not to be missed. Overseas visitors and all members of the department were made welcome and surprise arrivals of family or friends, often from considerable distances, added special sparkle. As their four sons grew up they joined in the fun and became friends to the children of many colleagues.
In 1972 David Baum moved with the core of the Hammersmith team to the brand new academic department of Paediatrics in Oxford. The then recently opened John Radcliffe Maternity Hospital, adjacent to the relocated Nuffield Institute for Medical Research, was soon to flourish as a leading perinatal centre. With Tizard presiding, Baum and his sparring partner Cliff Roberton formed the focus of an ever-enlarging clinical and research team. Ward rounds in the Nursery were a constant challenge in objective precision. Did we really know? If not, why not, and how would we find out? Research studies blossomed, many leading to critically acclaimed publications. Junior colleagues were encouraged to play a central role.
Baum soon realised how important nutrition is to the future well-being of sick babies. Convinced that even the most immature needed their mother's breast milk, he encouraged a band of ingenious bio-engineers to adapt ultrasonic flow transducers to measure breast milk flow during normal feeding. In 1976 he shared in inventing the Human Milk Pasteuriser, thus extending the benefits of breast milk to premature babies. Modern feeding advice stems from this unique work. In the same year Baum was awarded the Guthrie Medal of the British Paediatric Association for his contribution to paediatric research. The sense of common purpose engendered in this exciting era of modern medicine had long-lasting effects.
His expertise as a profoundly dedicated and caring physician, and his enquiring mind, encouraged and enthused everyone. Even before reaching consultant status Baum had fostered the careers of many who were later to direct departments throughout the world. The success of present-day care of sick and premature babies owes a huge debt to his meticulous pioneering work.
However there were other challenges in Oxford that needed attention. His interest in biochemistry and chronic disorders led him to take on the care of children with diabetes. He co-ordinated previously disparate services into a finely tuned multi-disciplinary team, including a child psychiatrist and community-based specialised nurse, that became a model for others throughout the country. Annual diabetic camps for adolescents became popular events, and in 1985 he published Care of the Child with Diabetes.
His international reputation in childhood diabetes grew and through his well-rehearsed lectures and enthusiastic participation in the European Society of Paediatric Research he made many friends. He was elected Secretary, 1983-87. His concern for families and particularly children with terminal illnesses led to his involvement in promoting the foundation of Helen House, the first children's hospice in the UK, and later the National Association for Care of Children with Life Threatening Diseases and their Families. After becoming Clinical Reader in Oxford he was elected to a Professorial Fellowship at St Catherine's College, where he had a happy association until his appointment in 1985 to the Chair of Child Health in Bristol.
Involved in all aspects of medical student teaching, he also used his consummate political skills to secure the funds needed to transform an unused nurses' hostel into an Institute of Child Health. This has been so successful that it will be relocated into the structure of the new Bristol Children's Hospital due to open next year.
He took on many administrative positions, including the chairmanship of a wide range of national and international executive and advisory boards and university committees but it was through the British Paediatric Association that he was most actively involved, first as secretary, and then chairman, of the Academic Board and as director of the Research Unit.
Frustrated that the unique needs of children were not getting proper recognition by government, Baum became convinced that progress would only come about through the establishment of a Royal College. He played a leading part in promulgating the case and in articulately persuading others. The Royal Charter of the Royal College of Paediatrics and Child Health was granted in 1996 and soon afterwards Baum was elected President. His presidency was marked by a rapid increase in the responsibilities of the fledgling college.
Baum recognised the importance of changes in practice that the profession is undergoing at present and the asset of a rapidly increasing number of women in leading roles in paediatrics. An ambitious college strategy covering all aspects of child health including training, examinations and international affairs was launched. Throughout this time Baum's wise and considered leadership has prevailed. He was elected a founder Fellow of the Academy of Medical Sciences and most recently a member of the General Medical Council.
His death occurred as he was characteristically leading by example on a bicycle ride to raise money for the wellbeing of children in the war- torn Balkans.
John David Baum, paediatrician: born Birmingham 23 July 1940; Lecturer, then Clinical Reader in Paediatrics, Oxford University 1972-85, Professorial Fellow, St Catherine's College 1977-85; Professor of Child Health, Bristol University 1985-99, Founding Director, Institute of Child Health 1988- 99; President, Royal College of Paediatrics and Child Health 1997-99; married 1967 Angela Goschalk (four sons); died Harlow, Essex 5 September 1999.