Prone positioning may improve oxygenation in patients with COVID-19-related pneumonia
Prone positioning was feasible and effective in rapidly improving blood oxygenation in spontaneously breathing, nonintubated patients with COVID-19-related pneumonia, according to data published in The Lancet Respiratory Medicine.
“Prone positioning in intubated mechanically ventilated patients affected by severe acute respiratory distress syndrome has been clearly demonstrated to be effective in reducing mortality,” Giuseppe Foti, MD, associate professor and chief of the department of emergency anesthesia and intensive care at the University of Milan-Bicocca, Italy, told Healio.“[But] prone positioning in nonintubated acute respiratory distress syndrome patients has been almost never applied.”
The PRON-COVID prospective cohort study enrolled 56 patients (mean age, 57.4 years; 79% male; mean BMI, 27.5 kg/m2) with a confirmed COVID-19-related pneumonia diagnosis requiring oxygenation or noninvasive CPAP. All patients were receiving care at San Gerardo Hospital in Monza, Italy, from March 20 to April 9, 2020. Patients were helped into the prone position; this position was maintained for 3 hours. Researchers collected data at baseline, 10 minutes after prone positioning and 1 hour after patients returned to the supine position.
Primary outcome was variation in oxygenation, defined as partial pressure of oxygen (PaO2)/fractional concentration of oxygen in inspired air (FiO2) from baseline to resupination.
Prone positioning was maintained for at least 3 hours in 47 patients (83.9%; 95% CI, 71.7-92.4). Oxygenation was improved significantly from supine to prone positioning; PaO2/FiO2 ratio was 180.5 mm Hg in the supine position compared with 285.5 mm Hg in the prone position (P < .0001). After returning to the supine position, the improvement in oxygenation was maintained in 23 patients (50% responders; 95% CI, 34.9-65.1), but was not significant compared with before prone positioning (PaO2/FiO2 ratio, 192.9 mm Hg 1 hour after resupination; P = .29), according to the results.
“Prone positioning was feasible for at least 3 consecutive hours in almost 85% of subjects and in all patients [partial pressure of oxygen] greatly improved and dyspnea decreased,” Foti said.
Those who maintained increased oxygenation had increased levels of inflammatory markers including C-reactive protein (12.7 mg/L in responders vs. 8.4 mg/L in nonresponders) and platelets (241.1x103/µL in responders vs. 319.8x103/µL in nonresponders), as well as shorter time between hospital admissions and prone positioning (2.7 days in responders vs. 4.6 days in nonresponders) than those in whom oxygenation was not maintained, according to the results.
Need for tracheal intubation was not significantly different between responders (30%) and nonresponders (26%).
Overall, the researchers observed no adverse events related to prone positioning in this cohort. Five patients died during the follow-up period, which the researchers said was attributed to underlying diseases.
According to the researchers, the results of this study suggest prone positioning in awake, spontaneously breathing patients is practical outside of the ICU environment.
“In the scenario of shortage of ICU beds, such as the one we observed in Lombardy, an improvement in PaO2 and dyspnea may be very relevant in order to possibly reduce necessity of ICU resources,” Foti said. “It is absolutely mandatory to perform a randomized control trial to evaluate the possible benefit of this strategy in terms of major outcome.”