Oxygen Therapy Coverage Criteria

Oxygen Therapy Coverage Criteria
Medicare Coverage and Payment Rules

COVERED BLOOD GAS AND/OR O2 SATURATION VALUES
Initial claims for oxygen therapy must include the results of a blood gas study or the results of a pulse arterial oxygen saturation that has been ordered and evaluated by the attending, or consulting, physician and performed under his or her supervision or when performed by a qualified provider or supplier of laboratory services. A DME supplier is not considered a qualified provider or supplier of laboratory services for purposes of these guidelines.
Group I Coverage is provided for patients with significant hypoxemia evidenced by any of the following:
*An arterial PO2 at or below 55 mm Hg OR an arterial O2Sat at or below 88%, taken at rest. When a PO2 of greater than 55 mm Hg is submitted, the service will be denied as not medically necessary unless "Group II" criteria are met.
*An arterial PO2 at or below 55 mm Hg OR an arterial O2Sat at or below 88%, taken during sleep for a patient who demonstrates an arterial PO2 at or above 56 mm Hg, or an arterial oxygen saturation at or above 89%, while awake, or a greater than normal fall in oxygen level during sleep (a decrease in arterial PO2 more than 10 mm Hg, or a decrease in arterial oxygen saturation more than 5%) associated with symptoms or signs reasonable attributable to hypoxemia, (e.g. cor pulmonale, "P" pulmonale on EKG, documented pulmonary hypertension and erythrocytosis). In either of these cases, coverage is provided only for nocturnal use of oxygen.
*An arterial PO2 at or below 55 mm Hg OR an arterial O2Sat at or below 88%, taken during activity for a patient who demonstrates an arterial PO2 at or above 56 mm Hg or an arterial oxygen saturation at or above 89%, during the day while at rest. In this case, supplemental oxygen is provided for during exercise if it is documented that the use of oxygen improves the hypoxemia that was demonstrated during exercise when the patient was breathing room air.
Group II Coverage is available for patients whose arterial PO2 is 56 to 59 mm Hg OR whose arterial O2Sat is 89% if any of the following are documented:
*Dependent edema suggesting Congestive Heart Failure (CHF);
*Pulmonary Hypertension or Cor Pulmonale, determined by measurement of pulmonary artery pressure, gated blood pool scan, echocardiogram, or "P" pulmonale of EKG (P wave greater than 3 mm in standard leads II, III, or AVF); OR
*Erythrocythemia with a hematocrit greater than 56%.
When a patient's initial certification for oxygen is approved based on Group II Coverage (an arterial PO2 of 56 to 59 mm Hg or an oxygen saturation of 89%), retesting between the 61st and 90th day of home oxygen therapy is required in order to establish continued medical necessity. For other recertification, retesting is not required, but the results of the most recent ABG or oximetry test representing the patient's chronic stable state must be included on the HCFA 484 (5/97) form.
Medicare must presume that home use of oxygen is not medically necessary for patients with arterial PO2 levels at or above 60 mm Hg OR an arterial O2Sat at or above 90%.
PORTABLE OXYGEN SYSTEMS
Medicare coverage of a portable oxygen system alone or to complement a stationary oxygen system (e.g. oxygen concentrator) may be allowed if the patient is mobile within the home.
REQUIRED DOCUMENTATION
The Certificate of Medical Necessity (CMN) for home oxygen is HCFA 484 (5/97) form. This form is used for initial certification, recertification, and changes in the oxygen prescription. This form must be filled out, signed and dated by the ordering physician and kept on file by the supplier.
Recertification is required 1 to 3 months after initial certification in patients (a) with a PO2, on certification, of 56 to 59 mm Hg or oxygen saturation of 89%, or (b) in whom the physician's initial estimate of length of need for oxygen was 1-3 months. For those patients for whom recertification at three months is not required, recertification will be required annually after initial certification. Once one recertification establishes the medical necessity for continued use of home oxygen, subsequent recertification will not be routinely required. However, a HCFA 484 (5/97) form should be submitted whenever there is a change in the oxygen prescription (e.g. increase or decrease in the oxygen flow rate, different equipment, etc.) or if there is a change of the attending physician. In addition, the DMERC may require subsequent recertification in individual cases.