Intensive care unit (ICU). A special segregated unit of a hospital in which patients are concentrated by reason of serious illness, usually without regard to diagnosis. Special lifesaving techniques and equipment regularly and immediately are available within the unit, and patients are under continuous observation by a nursing staff specially trained and selected for the care of this type patient. The unit is maintained on a continuing rather than an intermittent or temporary basis. It is not a postoperative recovery room nor a postanesthesia room. In some large or highly specialized hospitals, the ICUs may be further refined for special purposes, such as for respiratory conditions, cardiac surgery, coronary care, burn care, or neurosurgery. For the purposes of CHAMPUS, these specialized units would be considered ICUs if they otherwise conformed to the definition of an ICU.
32 CFR § 199.2
General. In an effort to be as specific as possible as to the word and intent of CHAMPUS, the following definitions have been developed. While many of the definitions are general and some assign meaning to relatively common terms within the health insurance environment, others are applicable only to CHAMPUS; however, they all appear in this part solely for the purpose of the Program. Except when otherwise specified, the definitions in this section apply generally throughout this part.