2005 OPEN FORUM Abstracts
A TEST FOR CLINICAL EQUIVALENCY: A PORTABLE CONCENTRATOR WITH INTEGRATED OXYGEN-CONSERVING COMPARED TO CONTINUOUS FLOW OXYGEN DURING NOCTURNAL USE
Robert McCoy, BS, RRT, FAARC Valley Inspired Products, Minneapolis, MN, Joseph Lewarski, BS, RRT, Inogen, Inc., Goleta, CA, Robert Chatburn, BS, RRT, FAARC, University Hospitals of Cleveland, OH
Introduction: Small, lightweight (~9.5 lbs) portable oxygen concentrators (POC) are a recent innovation in oxygen therapy. A technical requirement of POCs is the use of an integrated oxygen conserving device (OCD). Despite the large scale use of OCDs in awake and ambulating patients, published data is limited regarding the use of OCDs at night. This study was designed to compare heart rate and saturation of oxygen dependent sleeping patients using a POC with an OCD versus continuous flow oxygen.
Materials: Sleep Screening Device-(3rd Shift); Palmsat oximeter (Nonin Medical); WristOx (Nonin Medical); InogenOneT concentrator (Inogen, Inc.); Salter 1600 cannulas (Salter Labs).
Methods: Ten home oxygen patients on various CF oxygen systems and prescriptions (range 0.75-3 lpm) were studied. Informed consents were obtained in accordance with the IRB. The study group consisted of 4 males and 6 females, each acting as their own control in a crossover design. Nine patients had a primary diagnosis of emphysema and 1 patient had a primary diagnosis of pulmonary fibrosis. Age ranges were from 58 to 75. Each patient was screened to rule out co-morbid OSA. All patients underwent a baseline overnight oximetry study performed on their existing home oxygen system and prescription. Patients were titrated on the POC to determine an appropriate setting for overnight oxygen therapy. Titration was acceptable if the resting SpO2 was ≥ their baseline SpO2 on CF O2. The mean titrated POC oxygen setting was 2.9 (range 1-5). The patients received instruction on the use of the POC. Three patients operated the POC on the default setting (standard OCD sensitivity) and 7 patients set the device to the sensitive OCD setting. Data was compared via paired t-test. A power analysis confirmed the sample size was large enough to detect a difference in SpO2 of 4% and a difference in heart rate (HR) of 5 beats/min with a power of > 0.80.
Results: *All reported results reflect mean values
|CF baseline||Study||CF Baseline||Study|
|POC- All Patients||95.9||93.7||77||78|
|POC- Sensitive OCD Setting||96.4||94.9||75||74|
|POC -Default OCD Setting||94.7||90.9||83||88|
There was no statistically significant or clinically significant difference between the baseline and study SpO2 (95.7% vs 93.2%, p = 0.064) or heart rate (76.5/min vs 77/min, p = 0.70). Nine out of 10 patients maintained mean SpO2 and heart rates while sleeping on the POC essentially equivalent to that of their baseline study on CF O2. Patients using the device on the sensitive setting had less variance in both SpO2 and heart rate as compared to those on the default setting. One patient in the default setting group had a mean SpO2 of 86% while on the POC, a 10.9% change from her baseline and below the study threshold of 90%.
Conclusion: This study demonstrated that the InogenOneT POC was able to deliver adequate nocturnal oxygen therapy as evidenced by continuous SpO2 monitoring in 9 of 10 (90%) of patients studied. The resting daytime oxygen titration and the resultant SpO2 appears to be a reasonably effective method for determining an appropriate nocturnal oxygen setting.