As members of the medical community, most of us realize that cost must be balanced with appropriateness of care. However, dwindling reimbursement for care of patients in the home has created an aura of caution for those of us involved in this arena. In the current political environment even a well-intentioned study, if taken singularly, can become the focus to justify further cuts in reimbursement.
“Reevaluation of Continuous Oxygen Therapy After Initial Prescription in Patients with Chronic Obstructive Pulmonary Disease,” published in Respiratory Care, is one such study. The general premise of this study — that patients are not re-evaluated appropriately after initiation of continuous oxygen therapy – is certainly true in many cases. However, while the general premise is sound, the details slant the reader to believe that up to 60 percent of patients are on continuous oxygen therapy unnecessarily. Further, if one takes this study at face value, it is proposed that millions of Medicare dollars could be saved by proper re-evaluation.
| “Only by assessing all areas in which hypoxia exist can we ensure appropriate administration of home oxygen to patients.” |
Studies such as these should be critically examined. The proposed savings are extraordinary and will certainly catch the eye of government officials and managed care organizations. The title of this study leads us to believe that the focus was on patients with chronic obstructive pulmonary disease. In reality, the sample population of 226 patients contained less than half of this patient population (96 patients included in this study had the diagnosis of chronic obstructive pulmonary disease COPD and only 57 had actually been prescribed continuous oxygen therapy). Other groups in this study included patients with cancer, congestive heart failure, sleep apnea and the category “other.” Unfortunately, with home oxygen reimbursement trending downward, further hits could be justified by this study.
Whatever the author’s intent, the emphasis on appropriate re-evaluation is sound. The question that begs to be asked, however, is who determines what is appropriate? Are spot-check oximetry or arterial blood gases enough? Yuma Oba and others use these criteria in their study and are apparently satisfied that this is an appropriate amount of information to determine continued need for oxygen therapy. Perhaps in the case of pneumonia or asthma exacerbation this is adequate. This “moment in time” methodology, however, does not allow for desaturation during exertion or at night, and is therefore ineffective in determining the need for home oxygen for those patients with chronic lung or heart disease. The only way to adequately assess the need for oxygen in these cases is to include oximetry with ambulation and oximetry during sleep (nocturnal oximetry).
Oximetry with ambulation to assess the need for oxygen should be a standard of practice for those patients with COPD. Desaturating on their trek into the clinic, patients are usually adequately saturated by the time the doctor sees them. Typically they will have had 15 or 20 minutes of non-activity before oximetry is performed. Creating a standard of care, which includes oximetry with ambulation, would help to identify hypoxia in these patients. Without the benefit of this testing, these patients would have been deemed “normally saturated” and their home oxygen discontinued, obviously causing health problems in the future.
Nocturnal oximetry also is woefully underutilized. The only way to adequately assess the need or lack thereof for oxygen in patients with COPD or congestive heart failure (CHF) is to include overnight oximetry in the panel of testing. It is an inexpensive and simple way to determine if a patient is experiencing nocturnal hypoxia. Unfortunately, many clinics do not have oximeters at all, let alone one that is capable of performing overnight oximetry.
Further, many clinicians do not realize that overnight oximetry is reimbursable under Medicare and most private insurance, if billed under the appropriate code. This misconception probably stems from the fact that spot-check oximetry is usually bundled into the office visit and therefore not reimbursable as such. This is a shame as many patient/clinician friendly units are offered in low cost rent or lease-to-own programs provided by manufactures or vendors.
It is well documented that many COPD patients are at risk for nocturnal desaturation. Typically their deconditioned state leads to hypoventilation at night. Interestingly, it has been suggested that this patient population may need even more oxygen at night than they need during the day. Studies have suggested that patients on continuous oxygen therapy be evaluated for continued desaturation while sleeping, as their daytime liter flow may not be adequate at night suggesting even further applications for nocturnal oximetry.
CHF patients also are at risk for nocturnal desaturation. These patients tend to exacerbate their disease state, become hospitalized for IV Lasix and are only occasionally ordered home oxygen at discharge based on daytime saturation levels. When re-evaluated in the clinic, their daytime oxygen saturation tends to have normalized and their home oxygen discontinued.
Unfortunately, their nocturnal hypoxia is missed. It has been suggested that as many as 60 percent of CHF patients desaturate at night. Many experience Cheyne-Stokes breathing, which includes periods of apnea. As a result of their nocturnal hypoxia, patients are further decompensated and quality of life suffers.
Chronic hypoxia does not only affect quality of life. The physiological effects can be even more devastating. Most cells have the ability, albeit limited, to participate in anaerobic activity. Unfortunately the brain cells do not. In a hypoxic environment, cells in the brain either stop functioning or are killed as they are deprived of oxygen.
Further complications include damage to other extremely valuable organs – the kidneys and the liver. In addition, despite the muscle cell’s ability to perform in a chronically hypoxic state, “prolonged hypoxia markedly reduce(s) muscle force generation by skeletal muscles and their endurance to fatigue,” according to the previously mentioned study.
Additional tolls on the human body include the development of polycythemia, confusion, memory loss, right heart failure and hypertension. Increased myocardial work fatigues the heart muscle, increasing the risk for myocardial infarction. Oxygen is energy and the lack thereof leads to cellular dysfunction or death.
It is our responsibility to provide appropriate treatment to patients while simultaneously assuring cost control. Defining what constitutes appropriate treatment however is crucial. Only by assessing all areas in which hypoxia exist can we ensure appropriate administration of home oxygen to patients. Only if the standard of care includes spot check, ambulatory and nocturnal oximetry can we be sure that we are treating our patients in their entirety.
Baseline screening of oximetry with ambulation and at night has been suggested as an adjunct to early detection and treatment of hypoxia. There are several excellent reasons to incorporate baseline nocturnal oximetry into the panel of testing. Early identification and treatment of hypoxia prevents the long term effects of chronic hypoxia, which include development of CHF, cor pulmonale or hypertension and increase the risk for stroke.
Further, patients are typically more compliant with oxygen therapy at night. Increased compliance and decreased physiological effects of chronic hypoxia mean a decrease in the utilization of medical resources and hence a decrease in costs.
@.text:If baseline screening is not performed, there are other indicators which should alert the health care practitioner to the need for further oximetric evaluation in those patients with COPD and CHF. Complaints of poor sleep, orthopnea, morning headaches and fatigue may warrant ordering overnight oximetry. It has been further suggested that COPD patients with a daytime saturation of greater than or equal to 93 percent should be evaluated for nocturnal desaturation. Complaints of dyspnea on exertion, fatigue or decreased activity should be investigated by oximetry with ambulation. In addition, these tests should be performed before discontinuing continuous oxygen therapy.
Further study is certainly warranted. We may find that by incorporating overnight oximetry into our front line panel of screening, many patients would be under served. We may also find that earlier screening for nocturnal and exertional hypoxia will help to improve quality of life and decrease mortality and morbidity within these patient populations. By utilizing these simple and cost effective tools we set standards that assure cost containment with appropriateness of care.
Allen is a Registered Respiratory Therapist who works for a national home oxygen company in Oregon. She has worked for more than eight years in all aspects and areas of the respiratory care field, including adult, pediatric and neonatal intensive care, long term facilities and in the home. She is currently pursuing a bachelor’s of arts degree in Management of Health Services.
This article appeared in the September 2000 issue of Home Health Products, Vol. 8, No. 8.
