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

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.

[Brain natriuretic peptide in primary care: diagnostic value in heart failure]. / Péptido cerebral natriurético en atención primaria: valor diagnóstico en la insuficiencia cardíaca.

OBJECTIVE: To determine the validity and usefulness of brain natriuretic peptide (BNP) for diagnosing left ventricular dysfunction (LVD). DESIGN: Prospective, descriptive, multi-centred study to validate the diagnostic test. SETTING: Primary care centres in the Community of Madrid, Spain. PARTICIPANTS: Consecutive sample of patients at high risk of presenting with LVD. INTERVENTIONS: Data will be gathered from anamnesis, physical examination, ECG, and chest x-ray to find the risk factor(s) for LVD and the presence or absence of symptoms of congestive heart failure according to the Framingham scale. BNP will be determined at PC clinics in all patients who meet the inclusion criteria, using the "triage BNP test." All patients included in the study will be referred to an echocardiography service for an echocardiogram, which will be the gold standard test. Two independent cardiologists will evaluate the echocardiograph without knowing the BNP values. MAIN MEASUREMENTS: BNP concentrations will be compared against the kind and degree of LVD. ROC curves analysis will test the capacity of BNP to diagnose LVD. Optimal sensitivity and specificity value will be calculated by means of the position on the curve resulting from the minimum distance at the cut-off point for best sensitivity and specificity. Then, sensitivity, specificity, and positive and negative predictive values will be calculated. DISCUSSION: BNP can complement the information provided by other diagnostic tests. It should be included as an important factor in the taking of clinical-therapeutic decisions.