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Expired CO2 Measurement in Intubated or Spontaneously Breathing Patients from the Emergency Department
Published on: January 30, 2011
[Measurement of mask leakage during CPAP in patients with obstructive sleep apnea]
1Klinik für Pneumologie, Allergologie und Schlafmedizin, Klinik Ambrock, Universität Witten/Herdecke, Hagen.
Unlabelled:
To improve the compliance of patients with obstructive sleep apnoea tight fitting nasal masks are necessary. It would be very useful to to measure the mask leakage during the recommended pressure for the treatment at home. We studied therefore the influence of different sizes and types of masks on the air leaks during the adaptation procedure. We investigated 20 patients, mean age 60.8 +/- 11.9 years, AHI 31 +/- 17, lowest oxygen saturation 81 +/- 10.3% mean CPAP-9.9 +/- 1.6. Randomized cross over we applied CPAP with different masks during wakefulness. The pressure was increased from 6 to 13 mbar by steps of 1 mbar. The mask leak was measured by Autoset.
Results:
Using the best mask (selected from different sizes and different brands) the mask leak was 0.11 +/- 0.9 L/sec. If the patient used a mask (only one brand but selected from different sizes) or one standard mask the mask leak doubled respectively tripled. To reduce side effects and improve compliance we recommend therefore quantification of the mask leak to find the best fitting mask.
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