Out-of-hospital helmet CPAP in acute respiratory failure reduces mortality: a study led by nurses

Abstract

Background and Aim. Acute respiratory failure (ARF) is a condition that must be treated as quickly as possible. Continuous Positive Airway Pressure (CPAP) is a common method used to treat ARF in hospital. The main objective of our study was to investigate the effect of CPAP prior to admission to the emergency room, on the reduction of endotracheal intubation, in-hospital mortality and on the length of stay in hospital (HLOS). Methods. A prospective, observational (non-randomised) study with a historical control group. Data from 3 groups of patients with ARF, irrespective of cause, was collected: pre-hospital CPAP (PHCPAP) group, i.e. 35 patients treated with a helmet CPAP in the ambulance, by trained nurses (mean age, years 80.1±7.9 SD; 14 males); hospital CPAP (HCPAP) group, i.e. 46 patients treated with helmet CPAP in the hospital emergency room (mean age 78.6±6.9 SD; 27 males), and a historical control group of 125 patients treated with medical therapy only (mean age 76.7±5.5 SD; 52 males). CPAP was delivered via a helmet interface. Results. Compared with standard medical therapy, helmet CPAP (pre and in-hospital) reduced mortality by 77 % (p=0.005), while pre-hospital helmet CPAP reduced it by 94% (p=0.011), after adjustment for age, sex, severity of clinical conditions at entry and diagnosis upon admission. HLOS was reduced, compared with standard medical therapy, by 63.5% and by 66% (adjusting for age, sex, severity of clinical conditions at entry and diagnosis at admission) with helmet CPAP (pre and in-hospital) and with helmet CPAP in the ambulance, respectively (p<0.0001). Conclusions. Treating patients with ARF of any cause, with CPAP by trained nurses, before hospital admission, is safe, reduces mortality and the length of stay needed in hospital.