Effekte eines Oxymizers im Vergleich zu einer konventionellen Sauerstoffbrille im Tagesverlauf bei Patienten mit interstitiellen Lungenerkrankungen

The term „Interstitial Lung Disease (ILD)” sums up a variety of disease patterns which affect the structure of the lung tissue. Idiopathic pulmonary fibrosis (IPF), the most common form of ILD, has a progressive and severe disease process. Despite a new drug therapy with Pirfenidon and Nintedanib, mortality rate of IPF is still high. Only a lung transplantation is considered to be curative. But due to the limited availability of transplants and high perioperative risks, it is only an option for a small number of patients. With a progressing disease, especially the increasing dyspnoea, caused by hypoxia, reduces the quality of life of ILD patients. As a treatment for hypoxia, national and international guidelines recommend a long-term oxygen therapy. Portable liquid oxygen units are supposed to supply patients with oxygen while being apart from domestic oxygen reservoirs. Especially if high flow oxygen is needed, the low capacity of portable devices limits the patients’ mobility. To configure oxygen supply more effectively, a special nasal cannula with reservoir (Oxymizer) stores oxygen during expiration and releases a higher amount of oxygen during inspiration. Former studies have shown that the device can reduce hypoxia better than a standard nasal cannula (KSB). Due to a more effective supply of oxygen by the Oxymizer, it is possible to reduce the flow rate. This results in a higher capacity of the portable devices and allows patients more mobility. Previous studies investigated the Oxymizer just over a short period of time during rest or exercise. This study examines if patients with ILD benefit from the Oxymizer in their daily life. In a prospective and randomised trial 18 ILD patients were evaluated during pulmonary rehabilitation at Schön Klinik Berchtesgadener Land. All patients had an indication for long term oxygen therapy (flow rate ≥2 l/min). On consecutive days they used a standard nasal cannula, the Oxymizer with usual flow rate and the Oxymizer with reduced flow rate in randomised order. In addition to their usual rehabilitation schedule, the patients performed a supervised ten-minute walk at moderate intensity while a pulsoxymeter was continuously recording oxygen saturation. Additionally patients wore a SenseWear Armband to check their physical activity. The entire procedure was repeated one week later. The averaged results of the days with the standard cannula were compared to the results of the days with the Oxymizer. On days with the Oxymizer and usual flow rate, the minimal oxygen saturation (Median OXY 69,10 %; KSB 62,15 % p=0,01) and the saturation during the ten-minute walk were significantly higher compared to days with standard nasal cannula. (Median OXY 86,65 %; KSB 84,93%; p=0,01). Also, the time with insufficient oxygenation (SpO2 <88 %) could be significantly reduced on days with the Oxymizer and usual flow rate (Median OXY 14,51 %; KSB 16,34 %; p=0,02). The average saturation was just a bit higher with the Oxymizer (Median OXY 92,97 %; KSB 92,78 %; p=0,04). On days with the Oxymizer and reduced flow rate oxygen saturation was similar to days with KSB. In general, despite of a reduced flow rate, oxygen levels were slightly better. As these results illustrate, concerning the daily average, the Oxymizer has hardly any significant clinical benefit for patients with ILD. However, during daily exercise the Oxymizer improves oxygen effects significantly. The time with insufficient oxygenation -and therefore the risk of possible hypoaxaemic damages – can be reduced through the use of the Oxymizer. The outcomes of the measurements with reduced flow rate show that patients might obtain more mobility by reducing the flow rate while using the Oxymizer. Therefore, despite the limited carrying comfort, the Oxymizer might increase the patients’ quality of life.