life support 
noun [mass noun]
The use of specialized equipment to maintain a person’s essential physical functions when they are very ill or in an environment such as space or under water: his wife decided to remove him from life support and take him home to die with hospice care a patient on life support figurative the measures might get the technology sector off life support...
- Under the current system, most organs are donated by patients on life support machines who die after suffering irreversible brain damage.
- Systems that use living organisms to perform life support system functions are called bioregenerative life-support systems.
- For example, suppose a doctor refuses to withdraw life support from an incompetent patient when the clinical team agrees it to be appropriate.