Utilization of Airway Pressure Release Ventilation as a Rescue Strategy in COVID-19 Patients: A Retrospective Analysis

Abstract

Background: Airway Pressure Release Ventilation (APRV) is a pressure controlled intermittent mandatory mode of ventilation characterized by prolonged inspiratory time and high mean airway pressure. Several studies have demonstrated that APRV can improve oxygenation and lung recruitment in patients with Acute Respiratory Distress Syndrome (ARDS). Although most patients with COVID-19 meet the Berlin criteria for ARDS, hypoxic respiratory failure due to COVID-19 may differ from traditional ARDS as patients often present with severe, refractory hypoxemia and significant variation in respiratory system compliance. To date, no studies investigating APRV in this patient population have been published. The aim of this study was to evaluate the effectiveness of APRV as a rescue mode of ventilation in critically ill patients diagnosed with COVID-19 and refractory hypoxemia. Methods: We conducted a retrospective analysis of patients admitted with COVID-19 requiring invasive mechanical ventilation who were treated with a trial of APRV for refractory hypoxemia. PaO2/FIO2 (P/F ratio), ventilatory ratio and ventilation outputs before and during APRV were compared. Results: APRV significantly improved the P/F ratio and decreased FIO2 requirements. PaCO2 and ventilatory ratio were also improved. There was an increase in tidal volume per predicted body weight during APRV and a decrease in total minute ventilation. On multivariate analysis, higher inspiratory to expiratory ratio (I: E) and airway pressure were associated with greater improvement in P/F ratio. Conclusions: APRV may improve oxygenation, alveolar ventilation and CO2 clearance in patients with COVID-19 and refractory hypoxemia. These effects are more pronounced with higher airway pressure and inspiratory time.

Airway Pressure Release Ventilation for Acute Respiratory Failure Due to Coronavirus Disease 2019: A Systematic Review and Meta-Analysis

“…Five studies 17,[20][21][22][23] were included in the analysis of PaO 2 / FiO 2 ratio and four studies 17,[21][22][23] were included in the analysis of PaCO 2 . Compared to CMV, APRV was associated with a 33% increase in PaO 2 /FiO 2 ratio (RoM, 1.33; 95%CI, 1.21-1.48; I², 29%) (Figure 5) and a 9% decrease in PaCO 2 (RoM, 0.91; 95% CI, 0.85-0.98; I², 0%) (Figure 6).…”

“…In CMV, a superimposed negative pleural pressure can add to the transpulmonary pressure leading to a significant end-inspiratory stress and hence ventilator induced lung injury. Ibarra-Estrada 17 Jain 18 Zorbas 19 Joseph 20 Koszutski 21 Mahmoud 22 Sathyanarayanan 23 Study The use of other rescue therapies like inhaled pulmonary vasodilators (IPVDs) and prone positioning is another variable which can affect the outcome, but unfortunately was not consistently applied across studies. In ARDS, early prolonged prone positioning improved mortality, 27 while IPVDs improved oxygenation with no reduction of mortality.…”

“…Of 181 articles screened, seven studies with a combined population of 354 patients satisfied the inclusion criteria (Figure 1), including one RCT, 17 two cohort studies, 18,19 and four beforeafter studies with no control group. [20][21][22][23] All studies were conducted in 2020, including one pre-print 21 and two conference abstracts. 18,23 The authors of the abstracts responded to our request for further details, with one provided us with the full text of the unpublished manuscript.…”

Does airway pressure release ventilation offer new hope for treating acute respiratory distress syndrome?

“…Whether coronavirus disease 2019 (COVID-19) infection is a typical manifestation of ARDS is still controversial, [34] , [35] , [36] but the main pathology of COVID-19 including cytokine storm and excessive inflammation is similar to traditional ARDS. [37] , [38] , [39] Recently, Mahmoud et al [40] found that APRV may improve oxygenation, alveolar ventilation, and CO 2 clearance in patients with COVID-19 and refractory hypoxemia. Moreover, Zorbas et al [41] urged caution with the use of APRV in patients with COVID-19.…”

Ventilación con liberación de presión en las vías respiratorias (APRV): un enfoque para su uso correcto

“…El objetivo de tener una presión alta por un tiempo prolongado es mantener la apertura alveolar por el mayor tiempo posible y así aumentar la presión media de la vía aérea; el tiempo de la presión baja conjuntamente con la frecuencia respiratoria determinan la ventilación alveolar y se deben modificar conforme las metas de CO2 requeridas. La ventaja de APRV es que durante todo el tiempo el paciente podrá tener ventilación, disminuyendo las asincronías y manteniendo la actividad diafragmática [7].…”