Critical Care Services and the Medical Necessity Component


Critical care services must be medically necessary and reasonable. Current Procedural Terminology (CPT) Code 99291 should be billed when the patient requires critical care. In some instances, the patient may require critical care for the first day, but not on subsequent days as their condition has stabilized.

Critical care is defined as a physician’s direct delivery of medical care for a critically ill or critically injured patient. A critical illness or injury acutely impairs one or more vital organ systems such that there is a high probability of imminent or life threatening deterioration in the patient’s condition.

Critical care involves high complexity decision making to assess, manipulate, and support vital systems functions to treat single (or multiple) vital organ system failure, and/or prevent further life threatening deterioration of the patient’s condition.

The IOM Publication 100-4, Chapter 12, section 30.6.12(B) states that services provided that do not meet critical care services or services provided for a patient who is not critically ill or injured in accordance with the above definitions and criteria but who happen to be in a critical care, intensive care, or other specialized care unit should be reported using another appropriate E/M code (e.g., subsequent hospital care CPT codes 99231–99233).

Records that may require further review would include:

  • Charges submitted on the claim for critical care every day that the patient was in the critical care unit, when critical care (by definition) was not rendered
  • Unclear documentation of the critical care rendered vs non-critical services performed
  • The record does not reflect the time that the physician was at the patient’s immediate bedside or elsewhere on the floor, or unit, and immediately accessible. For each medical encounter, the physician’s progress notes must document the total time that critical care services were provided.

Remember that the medical record documentation must support that the critical care services each physician provided were necessary for treating and managing the patient’s critical illness(es) or critical injury(ies).

Recommended Resource

  • CMS IOM Publication 100-4, Chapter 12, section 30.6.12(B) (PDF)




Last Updated: 08/03/2020