Effectiveness of Prehospital Continuous Positive Airway Pressure in the Management of Acute Pulmonary Edema

Abstract

Objective. To compare the effectiveness of continuous positive airway pressure (CPAP) with standard pharmacologic treatment in the management of prehospital acute pulmonary edema. Methods. Using a nonrandomized control group design, all consecutive patients presenting to two participating emergency medical services (EMS) systems with a field impression of acute pulmonary edema between July 1, 2004, andJune 30, 2005, were included in the study. The control EMS system patients received standard treatment with oxygen, nitrates, furosemide, morphine, and, if indicated, endotracheal intubation. The intervention EMS system patients received CPAP via face mask at 10 cm H₂O in addition to standard therapy. Results. Ninety-five patients received standard therapy, and120 patients received CPAP andstandard therapy. Intubation was required in 8.9% of CPAP-treated patients compared with 25.3% in the control group (p = 0.003), andmortality was lower in the CPAP group than in the control group (5.4% vs. 23.2%; p = 0.000). When compared with the control group, the CPAP group had more improvement in respiratory rate (−4.55 vs. −1.81; p = 0.001), pulse rate (−4.77 vs. 0.82; p = 0.013), anddyspnea score (−2.11 vs. −1.36; p = 0.008). Using logistic regression to control for potential confounders, patients receiving standard treatment were more likely to be intubated (odds ratio, 4.04; 95% confidence interval, 1.64 to 9.95) andmore likely to die (odds ratio, 7.48; 95% confidence interval, 1.96 to 28.54) than those receiving standard therapy andCPAP. Conclusion. The prehospital use of CPAP is feasible, may avert the need for endotracheal intubation, andmay reduce short-term mortality.

Key words:

• EMS
• emergency medical services
• paramedic
• continuous positive airway pressure
• pulmonary edema
• respiratory distress