Risk factors for noninvasive ventilatory support failure in patients with COVID-19 pneumonia

Abstract

<b>Introduction:</b> SARS-CoV-2 pneumonia ranges from mild to severe disease requiring oxygen therapy, noninvasive or invasive ventilatory support (NI/I-VS). <b>Aim:</b> To investigate factors for NIVS failure in COVID-19 patients. <b>Methods:</b> Patients admitted to the Intermediate Care Unit of Coimbra Hospital and University Centre (Portugal) from September 1 2020 to January 31 2021 and treated with NIVS (CPAP, BiPAP or Helmet CPAP) were included. NIVS failure was defined as orotracheal intubation or death. Factors associated with NIVS failure with a univariate significance level of p&lt;0.10 were included in a multivariate analysis and odds ratios (OR) with 95% confidence intervals (CI) were calculated. A p&lt;0.05 was considered statistically significant. <b>Results:</b> A total of 160 patients were included; 63.1% (101) were male and the median age was 70 years. Twenty-one patients (13.1%) were intubated. The in-hospital mortality rate was 31.9% (51). The initial NIVS was the following: 21.3% (34) CPAP; 75% (120) BiPAP; 3.8% (6) Helmet-CPAP. On univariate analysis, age, time since symptoms to NIVS, arterial PaO2 before NIVS, maximal NIVS inspiratory and expiratory positive pressure (PAP), Remdesivir, Dexamethasone or Morfine use were more frequently associated with NIVS failure. Multivariate logistic regression analysis confirmed age and maximal IPAP as independent factors associated with the outcome (OR 1.06, 95%CI 1.02-1.10, p=0.001; OR 1.37; 95%CI 1.13-1.66, p=0.001, respectively). Remdesivir use significantly lowered the odds of NIVS failure (OR 0.38; 95%CI 0.17-0.86, p=0.020). <b>Conclusion:</b> In this cohort age and maximal IPAP were independent risk factors for NIVS failure. Remdesivir use was a protective factor.