Derek Thomson is replacing Jeremy Rushmer, who has a new job in Cramlington.
Dr Thomson is a GP who has been a leading figure at Northumbria Healthcare – the trust set to eventually take over the Carlisle and Whitehaven hospitals – for several years.
Chris Flucker, a consultant anaesthetist at North Cumbria University Hospitals NHS Trust, has also been appointed to the role of deputy medical director.
Dr Rushmer presented his final report as medical director to the trust board at its meeting on Tuesday.
Both trust chairwoman Gina Tiller and chief executive Ann Farrar thanked him for his hard work since joining the trust from Northumbria in 2012 – the same time as Mrs Farrar was appointed.
Dr Rushmer returns to Northumbria Healthcare as director of its the new emergency care hospital.
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