1997 OPEN FORUM Abstracts
EVALUATION OF AN OXYGEN CONSERVING DEVICE WITH EXERCISE IN PULMONARY REHABILITATION
Catherine Kenny, B.S.Ed., R.R.T. Robert T. Dailey, A.A.S., R.R.T. Dr. Adi Gerblich, M.D. Lakeland Community College Kirtland, Ohio 44094
BACKGROUND: We evaluated the ability of an oxygen conserving device (OCD) to maintain oxygen saturation levels similar to continuous flow oxygen (CFO) in patients with Chronic Obstructive Pulmonary Disease (COPD) requiring supplemental oxygen with exercise. The OCD, developed by Western Medica, Inc., utilizes a microprocessor to continuously interact with the patient's ventilation and deliver oxygen through a nasal cannula for a percentage of the inspiration only. Inspiratory percentages can be set by the Respiratory Care Practitioner. The unit re-evaluates the inspiratory time every breath to continually readjust the length of the delivered inspiration. The amount of oxygen delivered will depend upon the set liter flow, respiratory rate, and inspiratory time percentage. METHOD: The sample population consisted of 12 participants diagnosed with COPD and actively enrolled in a Pulmonary Rehabilitation program. Each individual was currently using oxygen between 2 and 4 liters per minute with exercise. This was a blind test with the first day of exercise evaluated using CFO, the second day with the OCD. Three OCD's were set to deliver oxygen for 61.8% of inspiration. One unit was set to deliver oxygen for 40% of inspiration. The OCD units were color coded, but the therapists administering the tests were unaware of which unit was set at 40%. Data was collected at rest, 3 minutes, and 7 minutes of exercise on each of 3 pieces of equipment. The exercise equipment used included an airdyne bicycle, treadmill, and graded armcrank. Exercise prescriptions with metabolic levels were determined by the rehabilitation coordinators and the supervising Pulmonologist. Participants were monitored for changes in Sp02 and Heart Rate (HR). Results were evaluated using a paired t-test, a p-value of .05 was considered significant. Mean values for HR and Sp02 were calculated for both methods of oxygen delivery, on each piece of equipment, at rest and with exercise. Results: No statistical significance was found between the 2 methods of oxygen delivery. All of the OCD's were able to deliver oxygen in quantities sufficient to maintain values similar to those achieved with CFO. The OCD's continued to trigger at respiratory rates up to 44/minute. Participants were interviewed after completing the study. They reported little or no difference between the 2 methods of oxygen delivery. One participant noted that the cannula was heavy and uncomfortable. Conclusions: Our results indicate than an OCD developed by Western Medica, Inc., can be utilized by patients with COPD requiring oxygen during exercise. The OCD can be set to deliver oxygen when it will participate in gas exchange and can be attached to any oxygen delivery system. It can be used at rest as well as with exercise. The amount of oxygen saved will depend upon the liter flow, respiratory rate, and the subjects inspiratory time. For the ambulatory patient this oxygen conservation should allow increased time away from a stationary cylinder and reduce the amount of oxygen used each month.