Barotrauma in critically ill COVID-19 patients: a retrospective case-control study.

Background: There is increased incidence of barotrauma in COVID-19 patients, probably due to disease pathology, oxygen therapy and coughing. We aimed to retrospectively compare the characteristics, associations and outcomes of COVID-19 patients with and without barotrauma in the intensive care unit (ICU).
Methods: All adults admitted between October 1st and December 31st 2020 in the ICUs of a COVID-19 hospital were retrospectively analysed for presence of a 'barotrauma event' (presence of at least one of pneumothorax, pneumomediastinum, subcutaneous emphysema or bronchopleural fistula). A control group was formed by matching each case to a patient belonging to the same gender and age range from the remaining patients in the cohort, i.e., those without barotrauma. Demographic details, ICU stay details, details of oxygen therapy and ventilation, and outcomes were noted and compared.
Results: Of 827 patients, 30 patients (3.6%) developed barotrauma events. The typical patient was middle aged (median age 55.5 years) and male (73.3%). The mortality rate was significantly higher in the barotrauma group (83.3% vs. 43.3%, P < 0.001), and odds of survival decreased by 85% if barotrauma occurred (OR 0.15; 95% CI: 0.46-0.51). Patients who developed barotrauma spent a longer time on a high-flow nasal cannula (median 6.7 vs. 1.73 days, P = 0.04), and mechanical ventilation (median 9.54 vs. 0.867 days, P < 0.001), and had a longer ICU stay (median 15.5 vs. 9 days, P = 0.014). The most common event was pneumothorax (26/30).
Conclusions: Barotrauma in the COVID-19 ICU is associated with prolonged ICU stay, higher odds of mortality and longer duration spent on mechanical ventilation and a high-flow nasal cannula. Key words: barotrauma, ICU, COVID-19, mortality, pneumothorax.