Prevalence, risk factors and consequences of early clinical deterioration under non-invasive ventilation in emergency department patients: a prospective, multicentre, observational study of the French IRU Network

Non-invasive ventilation (NIV) is widely used in emergency settings for acute respiratory failure, with NIV failure, usually defined by the need for tracheal intubation, as its primary complication. In emergency settings where patients may not be intubated or or where NIV represents the ceiling of care, a pragmatic understanding of NIV failure requires a broader definition that incorporates early clinical deterioration, including presumptive intubation criteria. This study assessed the prevalence of early clinical deterioration under NIV initiated in emergency settings (emergency department [ED] or mobile emergency medical services [EMS]) and its associated variables. A prospective multicentre study was conducted in 68 French EDs and EMS in the Initiative Recherche Urgences (IRU) network. Adult patients (≥ 18 years) requiring NIV in emergency settings were included, excluding those with a known do-not-resuscitate order or low autonomy. The primary endpoint was early clinical deterioration under NIV at 1 h. Early clinical deterioration under NIV was defined as either (1) the need for tracheal intubation or; (2) the presence of presumptive criteria for intubation. Secondary endpoints were baseline factors associated with failure, the need for tracheal intubation or death within 7 days among patients surviving without tracheal intubation at 1 h, and 7-day mortality. A total of 198 patients were included over 5 days. Early clinical deterioration at 1 h was reported in 41% of the patients. Early clinical deterioration under NIV was associated with a Glasgow Coma Scale score < 14 (adjusted odds ratio [aOR] = 5.5, 95% confidence interval [CI] [1.8 –19.4]), heart rate > 115 beats per minute (aOR = 2.5, 95%CI [1.3–5.2]), and signs of increased work of breathing (aOR = 2.8, 95%CI [1.2–7.1]). Among the surviving patients not intubated at 1 h, 12% required intubation within 7 days in the Early Clinical Deterioration group and 3% in the No Early Clinical Deterioration group (p < 0.001). Within 7 days, 28% died in the Early Clinical Deterioration group and 10% in the No Early Clinical Deterioration group (p = 0.001). NIV failure was associated with increased 7-day mortality (aHR = 4.1, 95%CI [1.8–9.1]). Early clinical deterioration under NIV is common in EDs, affecting nearly one out of two patients, and is associated with higher 7-day mortality. Clinical trial registration Registered 2024 january, 23th. NCT06213623. Prior to the first inclusion.