19: Prone Positioning in Awake Patients With Covid-19-Associated Respiratory Failure: The Procarf Trial

Abstract

INTRODUCTION/HYPOTHESIS: Awake prone positioning (APP) has been increasingly used in patients with acute respiratory failure due to COVID-19; however, most data supporting this therapy are observational/retrospective. The aim of this trial was to compare the outcomes in COVID-19 patients managed with APP versus standard care (SC).METHODS: Randomized controlled superiority trial, which included patients with COVID-19 and requirement of oxygen through high-flow nasal cannula (HFNC). Patients were randomized to remain in APP as long as possible or SC while HFNC therapy was needed. The primary outcome was intubation rate; treatment failure, defined as intubation or death without intubation, and mortality were secondary, with a follow-up to 28 days. Baseline characteristics, physiological response to APP, factors associated to failure, and adverse events were also analyzed. RESULTS:We enrolled 216 patients to APP and 214 to SC. Baseline characteristics were similar. Intubation rate was 30% in APP and 43% in SC patients (RR 0.70; 95% CI 0.54-0.90, p=0.006); mortality was 33% and 37%, respectively (RR 0.89; 95% CI 0.69-1.15, p=0.37). At multivariate analysis, the factors associated to an increased risk of failure were respiratory rate at enrollment (p=< 0.001), SpO 2 /FiO 2 at enrollment (p=< 0.001), absence of silent hypoxemia (p=0.01), lung ultrasound score at enrollment (p=< 0.001) and D-dimer at hospital admission (p=< 0.001). Mean daily duration of APP was 9.4 h (5.6-12.9), with a median of 6 days (3.7-9.0). At ROC curve analysis, the best predictors of treatment failure were a daily duration of APP < 7.7h (AUROC 0.96, p=< 0.001), respiratory rate at enrollment ≥25 bpm (AUROC 0.93, p=< 0.001), D-dimer >1.4 mg/dL (AUROC 0.82, p=< 0.001), and a decrease in respiratory rate < 3 bpm after the first session of APP (AUROC 0.79, p=< 0.001). The most common adverse events were back pain in 16 (7.4%) patients and intravascular lines dislodgement in 14 (6.5%). CONCLUSIONS:We found APP is associated with a reduced risk of intubation, with no difference in mortality. As a safe and effective procedure, we suggest APP should be encouraged to all COVID-19 patients requiring oxygen support with HFNC, aiming for the longest daily duration as possible, with closer monitoring of patients with predictive factors of failure.

Mechanical Power Delivered by Noninvasive Ventilation Contributes to Physio-Anatomical and Clinical Responses to Early Versus Late Proning in COVID-19 Pneumonia*

“…Last, although we focused on NIV-delivered energy and not on the energy transferred from respiratory muscles to the lung, available evidence suggests no role for increased inspiratory effort in early COVID-19 progression (5,6,(30)(31)(32)(33)(34)(35)(36).…”