Ventilatory associated barotrauma in COVID-19 patients: A multicenter observational case control study (COVI-MIX-study)

BACKGROUND

The risk of barotrauma associated with different types of ventilatory support is unclear in COVID-19 patients. The primary aim of this study was to evaluate the effect of the different respiratory support strategies on barotrauma occurrence; we also sought to determine the frequency of barotrauma and the clinical characteristics of the patients who experienced this complication.

METHODS

This multicentre retrospective case-control study from 1 March 2020 to 28 February 2021 included COVID-19 patients who experienced barotrauma during hospital stay. They were matched with controls in a 1:1 ratio for the same admission period in the same ward of treatment. Univariable and multivariable logistic regression (OR) were performed to explore which factors were associated with barotrauma and in-hospital death.

RESULTS

We included 200 cases and 200 controls. Invasive mechanical ventilation was used in 39.3% of patients in the barotrauma group, and in 20.1% of controls (p<0.001). Receiving non-invasive ventilation (C-PAP/PSV) instead of conventional oxygen therapy (COT) increased the risk of barotrauma (OR 5.04, 95% CI 2.30 - 11.08, p<0.001), similarly for invasive mechanical ventilation (OR 6.24, 95% CI 2.86-13.60, p<0.001). High Flow Nasal Oxygen (HFNO), compared with COT, did not significantly increase the risk of barotrauma. Barotrauma frequency occurred in 1.00% [95% CI 0.88-1.16] of patients; these were older (p=0.022) and more frequently immunosuppressed (p=0.013). Barotrauma was shown to be an independent risk for death (OR 5.32, 95% CI 2.82-10.03, p<0.001).

CONCLUSIONS

C-PAP/PSV compared with COT or HFNO increased the risk of barotrauma; otherwise HFNO did not. Barotrauma was recorded in 1.00% of patients, affecting mainly patients with more severe COVID-19 disease. Barotrauma was independently associated with mortality.

TRIAL REGISTRATION

this case-control study was prospectively registered in clinicaltrial.gov as NCT04897152 (on 21 May 2021).

Severe acute respiratory failure due to a multifactorial diffuse alveolar haemorrhage

Diffuse alveolar haemorrhage (DAH) is a life-threatening syndrome caused by infection, coagulation disorders or autoimmune diseases. We here report the case of an 81-year-old male subject affected by a multifactorial DAH, in which the bleeding was related to the administration of clopidogrel and warfarin, both implicated in the context of a polycythaemia. He developed a severe acute respiratory failure treated with a ventilatory support by means of a continuous positive airway pressure (C-PAP) therapy. An improvement of patient's clinical conditions was observed only after clopidogrel and warfarin discontinuation.

Pleuritis with pleural effusion due to a Bacillus megaterium infection

Pleural effusions may be related to pleuro-pulmonary or systemic disorders, including malignancy. Thoracentesis and thoracoscopy may be useful to diagnosis. In some cases, the diagnosis may be difficult and uncommon. We report the case of a hospitalized male for a pleuritis, with pleural effusion caused by a Bacillus megaterium infection, a Gram-positive, aerobic, spore-forming, and rod-shaped bacterium. To our knowledge, our case report is the first evidence of pleuritis due to B. megaterium. In the literature, up to now, B. megaterium infection has only been reported as involving the eye, skin, and brain.