Protocol for assessing mortality reduction with the early use of noninvasive ventilation in prehospital emergency services: A multicentre, observational cohort study in Madrid, Spain

Abstract

Background: Acute respiratory failure (ARF) has become one of the most prevalent serious pathologies encountered in the emergency medical service (EMS). In hospital settings, noninvasive ventilation (NIV) therapy prevents complications from more aggressive treatments for that condition. However, the scarce evidence on the benefits of NIV in prehospital EMS (i.e., during transport to the hospital) is inconclusive.

Objectives: To determine whether the administration of NIV during prehospital EMS in cases of ARF reduces in-hospital mortality compared with starting NIV on arrival to in-patient EMS.

Methods: This is a multicentre, observational, prospective cohort study. We recruited a total of 317 patients from the Madrid region (Spain) who were prescribed NIV for their ARF using a nonprobabilistic consecutive sampling method. Analyses of the main outcome (in-hospital mortality) and secondary outcomes (length of hospital stay, readmissions, percentage of intensive care unit admissions, and cost-effectiveness) will include descriptive analyses of patients' characteristics, as well as bivariate and multivariate analyses and cost-effectiveness analysis.

Discussion: This study will provide data on NIV management in prehospital and in-patient EMS in patients with ARF. Results will contribute to the existing evidence on the benefits of NIV in the context of prehospital EMS while underlining the importance of a standardized formal training for physicians and nurses working in prehospital and in-patient EMSs.

Conclusion: The VentilaMadrid study will provide valuable data on the clinical factors of patients receiving NIV in prehospital EMS. Further, were our hypothesis to be confirmed, our results would strongly suggest that the administration of NIV in prehospital EMS by medical and nursing profesionals formally trained in the technique reduces mortality and improves prognoses.

Keywords: Acute respiratory failure; Chronic obstructive pulmonary disease; Emergency medical services; Mortality; Noninvasive ventilation; Prehospital care; Pulmonary edema.