An Experimental Pre-Post Study on the Efficacy of Respiratory Physiotherapy in Severe Critically III COVID-19 Patients

Background: Respiratory physiotherapy (RPT) is considered essential in patients' management during intensive care unit (ICU) stay. The role of RPT in critically ill COVID-19 patients is poorly described. We aimed to investigate the effects of RPT on oxygenation and lung aeration in critically ill COVID-19 patients admitted to the ICU. Methods: Observational pre-post study. Patients with severe COVID-19 admitted to the ICU, who received a protocolized CPT session and for which a pre-and post-RPT lung ultrasound (LUS) was performed, were included. A subgroup of patients had an available quantitative computed tomography (CT) scan performed within 4 days from RPT. The primary aim was to evaluate whether RPT improved oxygenation; secondary aims included correlations between LUS, CT and response to RPT. Results: Twenty patients were included. The median (1st-3rd quartile) PaO2/FiO(2) was 181 (105-456), 244 (137-497) and 246 (137-482) at baseline (T0), after RPT (T1), and after 6 h (T2), respectively. PaO2/FiO(2) improved throughout the study (p = 0.042); particularly, PaO2/FiO(2) improved at T1 in respect to T0 (p = 0.011), remaining higher at T2 (p = 0.007) compared to T0. Correlations between LUS, volume of gas (rho = 0.58, 95%CI 0.05-0.85, p = 0.033) and hyper-aerated mass at CT scan (rho = 0.54, 95% CI 0.00-0.84, p = 0.045) were detected. No significant changes in LUS score were observed before and after RPT. Conclusions: RPT improved oxygenation and the improvement persisted after 6 h. Oxygenation improvement was not reflected by aeration changes assessed with LUS. Further studies are warranted to assess the efficacy of RPT in COVID-19 ICU patients.