She will leave her current role as National Director for Commissioning Development to take the temporary roles in mid-April.
Rosamond Roughton, the current Director of Commissioning Systems and Strategy, will fulfil the commissioning development role.
The NHS CB has been searching for a new chief executive since Ian Dalton CBE announced he was ended his long career in the health service to join BT Global Services as President of Global Health.
Dame Barbara has played a pivotal role in the authorisation process of the new commissioning system, helping clinical commissioning groups and commissioning support units in their development.
In her new position – which includes the leadership of the Board’s Operations Directorate – she will be responsible for direct commissioning of certain services, including primary care.