Physiologic Improvement in Respiratory Acidosis Using Extracorporeal Co 2 Removal With Hemolung Respiratory Assist System in the Management of Severe Respiratory Failure From Coronavirus Disease 2019

Abstract

Objectives: About 15% of hospitalized coronavirus disease 2019 patients require ICU admission, and most (80%) of these require invasive mechanical ventilation. Lung-protective ventilation in coronavirus disease 2019 acute respiratory failure may result in severe respiratory acidosis without significant hypoxemia. Low-flow extracorporeal C o 2 removal can facilitate lung-protective ventilation and avoid the adverse effects of severe respiratory acidosis. The objective was to evaluate the efficacy of extracorporeal C o 2 removal using the Hemolung Respiratory Assist System in correcting severe respiratory acidosis in mechanically ventilated coronavirus disease 2019 patients with severe acute respiratory failure. Design: Retrospective cohort analysis of patients with coronavirus disease 2019 mechanically ventilated with severe hypercapnia and respiratory acidosis and treated with low-flow extracorporeal C o 2 removal. Setting: Eight tertiary ICUs in the United States. Patients: Adult patients supported with the Hemolung Respiratory Assist System from March 1, to September 30, 2020. Interventions: Extracorporeal C o 2 removal with Hemolung Respiratory Assist System under a Food and Drug Administration emergency use authorization for coronavirus disease 2019. Measurements and Main Results: The primary outcome was improvement in pH and Pa co 2 from baseline. Secondary outcomes included survival to decannulation, mortality, time on ventilator, and adverse events. Thirty-one patients were treated with Hemolung Respiratory Assist System with significant improvement in pH and P co 2 in this cohort. Two patients experienced complications that prevented treatment. Of the 29 treated patients, 58% survived to 48 hours post treatment and 38% to hospital discharge. No difference in age or comorbidities were noted between survivors and nonsurvivors. There was significant improvement in pH (7.24 ± 0.12 to 7.35 ± 0.07; p < 0.0001) and Pa co 2 (79 ± 23 to 58 ± 14; p < 0.0001) from baseline to 24 hours. Conclusions: In this retrospective case series of 29 patients, we have demonstrated efficacy of extracorporeal C o 2 removal using the Hemolung Respiratory Assist System to improve respiratory acidosis in patients with severe hypercapnic respiratory failure due to coronavirus disease 2019.

Extracorporeal Carbon Dioxide Removal With the Hemolung in Patients With Acute Respiratory Failure: A Multicenter Retrospective Cohort Study*

“…The study further supports the findings from several other previous studies that low-flow ECCO 2 R devices such as Hemolung are effective in improving hypercapnia while reducing the lung injury due to invasive mechanical ventilation (8,11,14,16,20). The overall survival rate of patients in this study is about 41% and is comparable with other studies that used ECCO 2 R (8,23,24). The mortality observed in this study showed significant differences across the diagnostic categories with a very low survival in COVID-19 ARDS patients (31%).…”

Bridge to second double lung transplant with an extracorporeal carbon dioxide removal system in situs inversus patient

“…4 HRAS has also been reported to improve acidosis in acute respiratory failure from coronavirus disease 2019. 9 Rajab et al reported the use of VV-ECMO via a right internal jugular Avalon cannula as a bridge to heart and lung transplantation in a patient with dextrocardia. 10 In our patient this was not an option because her superior and inferior vena cava were on the left side and her tricuspid valve was facing the right.…”

“…Bonnin et al reported using HRAS for severe chronic obstructive pulmonary disease bridge to lung transplant; a transplant was performed 31 days after induction of HRAS 4 . HRAS has also been reported to improve acidosis in acute respiratory failure from coronavirus disease 2019 9 …”

Acid–base imbalance as a risk factor for mortality among COVID-19 hospitalized patients

“…When compared to patients with normal ABG readings, RANC and MAC doubled the risk of fatality. Lung-protective ventilation in COVID-19 respiratory failure may result in severe respiratory acidosis without considerable hypoxemia [34]. The higher mortality rate in patients with respiratory acidosis may be due to the binding of protein S to angiotensin-converting enzyme 2 receptors, which penetrate alveolar epithelial cells, resulting in direct toxic effects and an overactive immune response.…”