critical care
noun /ˌkrɪtɪkl ˈkeə(r)/
  /ˌkrɪtɪkl ˈker/
(also intensive care)
 [uncountable]- continuous care and attention, often using special equipment, for people in hospital who are very seriously ill or injured- Technology has made life-saving critical care possible.
 
- (also critical care unit, CCU [countable])the part of a hospital that provides critical care- in critical care Patients in critical care are the most vulnerable, because they are very ill.
- She was transferred to the critical care unit.