This article is about life support in medicine. There is another article on life support and environmental control.
Life support is a colloquial term for a set of allopathic therapies to preserve a patient's life, usually in the absence of a reasonable hope that the patient will regain consciousness.
Life support therapies utilize some combination of several techniques: enteric feeding, intravenous drips,total parenteral nutrition, mechanical respiration, heart/lung bypass, defibrillation, urinary catheterization and dialysis.
The same techniques are also used for intensive care, but there is a slightly different emphasis. Life support is concerned with stabilizing a patient rather than healing them.
In some cases, skilled nursing care can substitute for one of the above radical therapies, and it is almost always preferable if it can be relied-upon. For example, some hospitals routinely train nurses to attach oxygen equipment to a patient's preferred breathing orifice, while others limit it to a nose cannula. The cannula is safer (from fire) than a tent and requires less care than a mask. An unconscious mouth-breather may be prescribed mechanical ventilation at a nose-cannula hospital, but not at an any-orifice or tenting hospital. For another common example, some hospitals have cardiac care nurses that can skillfully limit a patient's uptake of fluids, preventing their need to urinate, and thus their need for diuretic drugs and a urinary catheter.
In general, enteric feeding (called "tube feeding") is preferable to total parenteral nutrition. Urinary catheterization is preferable to dialysis. Mechanical ventilation or defibrillation are preferable to cardiac bypass, and can sometimes sustitute for it.