[3][2] After education at Emmanuel College, Cambridge and St Bartholomew's Hospital, he qualified MRCS, LRCP in 1936 and graduated MB BChir (Cantab.)
This allowed the crews of midget submarines and especially divers involved in the clearance of mines in captured ports to carry out their hazardous work.
Donald also collaborated there with Richard L. Riley (1911–2001) on research involving "ventilation-perfusion relationships and gas diffusion at the alveolo-capillary membrane of the lungs.
[2] At Birmingham he did research on pulmonary circulation, with a team including John Bishop, Gordon Cumming (1922–2001), Archie C. Pincock, and Owen Lyndon Wade (1921–2008).
[3] A striking finding was that in rheumatic heart disease the cardiac output did not increase much with exercise and sometimes not at all, although this could be reversed after successful valvotomy.