Risk factors for non-invasive/invasive-ventilatory support in patients with COVID-19 pneumonia: a retrospective study within a multidisciplinary approach

Int J Infect Dis. 2020 Sep 10;S1201-9712(20)30728-1. doi: 10.1016/j.ijid.2020.09.012. Online ahead of print.


Objectives: To investigate risk factors for non-invasive/invasive-ventilatory support (NI/I-VS) in Coronavirus diseases 2019 (COVID-19) patients.

Methods: All consecutive patients admitted, from February 25 to April 25, 2020, to the Infectious Diseases Unit and Intensive Care Unit of Santa Maria Annunziata Hospital (Florence, Italy) with confirmed COVID-19 diagnosis were enrolled in this retrospective cohort study. NI/I-VS was defined as need for continuous positive airway pressure (CPAP) or bilevel positive pressure non-invasive ventilation (BPAP) or mechanical ventilation (MV) than low-flow systems oxygen-therapy as Venturi Mask (VM) or nasal cannula.

Results: Ninety-seven patients were enrolled; 61,9% (60/97) were male, median age was 64 years; intra-hospital mortality was 9.3%. Thirty five out of 97 (36%) patients required ICU admission and 94.8% (92/97) were prescribed oxygen-therapy: 10.8% (10/92) with nasal cannula, 44.5% (41/92) with VM, 31.5% (29/92) with CPAP, 2.2% (2/92) with BPAP and 10.8% (10/92) underwent intubation for MV. Patients with body mass index >30, type II diabetes mellitus and presenting at the admission with dyspnoea, asthenia, SOFA score ≥2 points, PaO2/FiO2 < 300, temperature >38 °C, increased levels of lactate dehydrogenase (LDH), alanine aminotransferase, C-reactive protein and a d-dimer >1000 ng/ml underwent more frequently NI/I-VS at the univariate analysis. Multivariate logistic regression analysis confirmed temperature >38 °C (odds ratio [OR] 21.2, 95% confidential interval [95%CI] 3.5-124.5, p = 0.001), LDH > 250 U/L (OR 15.2, 95%CI 1.8-128.8, p = 0.012) and d-dimer >1000 ng/ml (OR 4.5, 95%CI 1.2-17.3, p = 0.027) as significantly associated with NI/I-VS requirement. A non-significant trend (p = 0.051) was described for PaO2/FiO2 < 300.

Conclusions: Temperature >38 °C, LDH > 250 U/L and d-dimer >1000 ng/ml resulted to be indipendent risk factors for NI/I-VS in COVID-19 patients. In order to quickly recognize patients likely at risk to develop a critical illness, inflammatory markers assessment should be warranted upon hospital admission.

Keywords: COVID-19; Italy; invasive ventilation; multidisciplinary; non-invasive ventilation; risk factors.