20 Miss. Code R. § 2-IX
Critical care is the direct delivery by a physician(s) 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 system function(s) to treat single or multiple vital organ system failure and/or to prevent further life threatening deterioration of the patient's condition. Examples of vital organ system failure include, but are not limited to: central nervous system failure, circulatory failure, shock, renal, hepatic, metabolic, and/or respiratory failure. Although critical care typically requires interpretation of multiple physiologic parameters and/or application of advanced technology(s), critical care may be provided in life threatening situations when these elements are not present. Critical care may be provided on multiple days, even if no changes are made in the treatment rendered to the patient, provided that the patient's condition continues to require the level of physician attention described above.
Providing medical care to a critically ill, injured, or postoperative patient qualifies as a critical care service only if both the illness or injury and the treatment being provided meet the above requirements. Critical care is usually, but not always, given in a critical care area, such as the coronary care unit, intensive care unit, pediatric intensive care unit, respiratory care unit, or the emergency care facility.
Services for a patient who is not critically ill but happens to be in a critical care unit are reported using other appropriate E/M codes.
Critical care and other E/M services may be provided to the same patient on the same date by the same individual.
The following services are included in reporting critical care when performed during the critical period by the physician(s) providing critical care: the interpretation of cardiac output measurements (93561, 93562), chest x-rays (71045, 71046) , pulse oximetry (94760, 94761, 94762), blood gases, and collection and interpretation of physiologic data (eg, ECGs, blood pressures, hematologic data);); gastric intubation (43752, 43753); temporary transcutaneous pacing (92953); ventilatory management (94002-94004, 94660, 94662); and vascular access procedures (36000, 36410, 36415, 36591, 36600). Any services performed which are not included in this listing should be reported separately.
Facilities may report the above services separately. The critical care codes 99291 and 99292 are used to report the total duration of time spent in provision of critical care services to a critically ill or critically injured patient, even if the time spent providing care on that date is not continuous. For any given period of time spent providing critical care services, the individual must devote his or her full attention to the patient and, therefore, cannot provide services to any other patient during the same period of time.
20 Miss. Code. R. § 2-IX