Pre-hospital Use of Continuous Positive Airway Pressure (CPAP) for Acute Severe Congestive Heart Failure (CHF)

Abstract

Objective: To describe the pre-hospital use of continuous positive airway pressure (CPAP) for patients presenting with acute severe congestive heart failure (CHF) in a large Emergency Medical Services (EMS) system. Methods: This study utilized a retrospective design of pre-hospital charts of patients treated by paramedics in the Monmouth and Ocean County EMS system for acute CHF. Inclusion criteria were placement of CPAP therapy by Mobile Intensive Care Unit protocol, respiratory rate (RR) > 25 breaths/min, labored and shallow breathing, bilateral rales, history of CHF, intact mental status, and pre-hospital diagnosis of CHF. Data collected included patient demographics, vital signs, oxygen saturation by pulse oximetry (SaO2), need for endotracheal intubation, and complications. All patients meeting inclusion criteria from January 1, 2005 to December 31, 2006 were included in this study. Results: A total of 1306 charts were reviewed; 387 patients met inclusion criteria. Of the 387, 149 patients had placement of CPAP (38.5%). When comparing patients that received CPAP to ones that did not, the out-of-hospital treatment times did not differ (CPAP = 30 min; non-CPAP = 31 min; p < 0.01); Adjunctive CHF treatment such as use of nitrates, diuretics, or morphine were similar between the two groups. The increase in post-treatment SaO2 was statistically significant (CPAP group 9% vs. non-CPAP 5%, p < 0.01). This was also true for systolic blood pressure (BP) reduction (CPAP 27.1 mm Hg, non-CPAP 19.9 mm Hg, p < 0.01), Diastolic BP reduction (CPAP 14.1 mm Hg, non-CPAP 7.4 mm Hg, p < 0.01), heart rate (HR) reduction (CPAP 17.2 beats/min, non-CPAP 9.6 beats/min, p < 0.01), as well as RR reduction (CPAP 5.63, non-CPAP 4.09, p < 0.01). Rate of pre-hospital intubation was higher in the non-CPAP group vs. the CPAP group (CPAP 2.6%, non-CPAP 5.46%, p < 0.01). Conclusion: The use of CPAP for eligible patients with acute severe CHF seems to be feasible and beneficial. Its use seems to result in improvement in oxygen saturation, improvement of vital signs, and decreased rates of pre-hospital intubation. Randomized prospective pre-hospital studies are needed to validate these results.