By Mike McEvoy
With multiple studies showing patient harm from supplemental oxygen administration, a study published ahead of the April/June 2012 printing of Prehospital Emergency Care finds less than 100 percent oxygen is safe with CPAP. Typical CPAP devices deliver 100 percent oxygen which decreases coronary blood flow and is associated with worsened outcomes in stroke, trauma, COPD, acute coronary syndromes and cardiac arrest.
Researchers used a CPAP device delivering 28-30 percent oxygen (Pulmodyne O2-RESQ) on 340 prehospital CPAP patients over a six-month period in Las Vegas. Of the patients treated, 241 (71.5 percent) improved, 51 (15.1 percent) stayed the same, and 45 (13.4 percent) were rated as worsened by EMS. Only 19 (5.6 percent) required prehospital intubation. During the first 15 minutes of CPAP, respiratory rates improved from a mean of 34.5 to 37.9 (p=0.00) and oxygen saturations improved from a mean of 81 percent to 94.2 percent (p=0.00) which happens to be the recommended oxygen saturation goal in the AHA Guidelines 2010. These findings correlate well with previous studies of CPAP using 100 percent oxygen, demonstrating that CPAP using lower FiO2 is safe and effective for patients with prehospital respiratory emergencies.
1. Bledsoe BE, Anderson E, Hodnick R, Johnson L, Johnson S, and Dievendorf E. Low-Fractional Oxygen Concentration Continuous Positive Airway Pressure is Effective in the Prehospital Setting. Prehospital Emergency Care. 2012;Early Online:1-5. Available at: http://informahealthcare.com/doi/abs/10.3109/10903127.2011.640765.
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