key: cord-348927-g69gt0oh
authors: Li, Tong; Yin, Peng-Fei; Li, Ang; Shen, Maxwell R.; Yao, Yong-Xing
title: Acute Respiratory Distress Syndrome Treated with Awake Extracorporeal Membrane Oxygenation in a Patient with COVID-19 Pneumonia
date: 2020-11-10
journal: J Cardiothorac Vasc Anesth
DOI: 10.1053/j.jvca.2020.11.017
sha: 
doc_id: 348927
cord_uid: g69gt0oh

nan

Since the first outbreak of coronavirus disease in December 2019, which was caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the disease has spread worldwide over the past months and become a globle pandemic. 1 Although most infections are mild, severe impairment of the respiratory system and acute respiratory distress syndrome (ARDS) may develop in patients with pre-existing comorbidities such as hypertension, diabetes, and other lung diseases. Extensive use of mechanical respiratory support and extracorporeal membrane oxygenation (ECMO) has helped to reduce the case fatality rate of COVID-19 to less than 2% in some regions. 2 However, various related complications, including pneumothorax, thrombosis, ventilator-associated infection, ventilator-induced lung injury, 2 systemic inflammation, and neurological complications may emerge during the use of conventional mechanically ventilated ECMO. 3 In recent years, ECMO without mechanical ventilation (MV) and sedation (awake ECMO) has been utilized in several subset populations. 4 Similar to conventional ECMO, awake ECMO also notablely improves oxygenation; awake ECMO exempts MV and avoids the complications associated with prolonged sedation and tracheal intubation. Awake and fully mobile ECMO have proven to be beneficial in patients with ARDS induced by pneumocystis pneumonia, immunocompromised patients, and patients requiring extracorporeal life support. [5] [6] [7] However, the use of awake ECMO has not been reported in ARDS patients secondary to COVID-19 pneumonia. In our case report, we managed a case of ARDS resulting from COVID-19 pneumonia with awake ECMO.

An 80-year-old female patient was admitted to our intensive care unit for severe bilateral pneumonia. Thoracic radiography showed diffuse whiteout of the lungs, and computed tomography (CT) showed bilateral multiple ground glass opacities ( Figure. 1A, 1B). Her main symptoms were persistent fever, cough, and shortness of breath for seven days. Her laboratory tests indicated a C-reactive protein concentration of 51.20 mg/dL, with a normal coagulation profile (D-dimer, 953 µg/L) and serum enzyme levels. A complete blood count revealed leukocytosis (13,500/dL), with neutrophil predominance (94.6%) and a low lymphocyte count (200/dL). The nasal and pharyngeal swab specimens tested positive for COVID-19 and negative for influenza A and B viruses, adenovirus, respiratory syncytial virus, and parainfluenza virus 1, 2, and 3. Initial arterial blood gas (ABG) analysis was performed, which showed a pH of 7.44, partial pressure of arterial oxygen (PaO 2 ) of 62.4 mmHg, partial pressure of arterial CO 2 (PaCO 2 ) 3 of 30.7 mmHg, and a low PaO 2 /FiO 2 ratio with a FiO 2 of 50%. High-flow oxygen therapy via the nasal cannula under a mask was initiated with the goal of maintaining her oxygen saturation (SpO 2 ) above 90%.

In an isolated room, the patient received intensive monitoring, antiviral therapy (arbidol 0. formation. An intravenous infusion of norepinephrine (3 µg/min) was titrated to maintain a stable blood pressure. Two hours later, she regained consciousness. She was hemodynamically stable, and norepinephrine was discontinued. The ABG analysis showed the following: PaCO 2 , 31.7 mmHg; PaO 2 , 69.2 mmHg (PaO 2 /FiO 2 = 221). After a comprehensive evaluation, she was extubated and received awake ECMO support. The flow rate was adjusted to 60 mL/kg/min, with air flow/blood flow of 0.8 to 1:1. After extubation, the patient was not breathless and had an RR of 20 breaths/min. She was in a good mental state and could feed herself. She received plasma (300 mL) from a convalescent donor who recovered from COVID-19, and two days later, her COVID-19 test result was negative. Her blood test showed a hemoglobin level of 8.5 g/dL; thus, packed red blood cells (400 mL) were administered. After 10 days of ECMO support, the patient's pulmonary function improved. Her ABG analysis showed the following: PaO 2 , 99 mmHg (FiO 2 , 30%); PaCO 2 , 37 mmHg; and SpO 2 , 98%. Her temperature was normal, with a heart rate of 77 beats/min and an RR of 22 breaths/min. Thoracic CT demonstrated a significant improvement in ground glass opacification from her previous scan (Figure. 1D ). Based on her 5 condition, the weaning process began while maintaining continuous assessment. The patient tolerated weaning well with a gradual reduction in the ECMO blood flow rate. On complete suspension, her ABG analysis showed the following: PaO 2 , 72 mmHg (FiO 2 , 30%); PaCO 2 , 45 mmHg; SpO 2 , 94% with stable hemodynamic parameters (blood pressure: 157/62 mmHg, heart rate: 76 beats per minute). The patient was successfully weaned off ECMO and recuperated under supportive care. The subsequent therapy period was uneventful. She was discharged from the hospital after 10 days of additional therapy with ABG analysis showing a PaCO 2 of 34 mmHg and PaO 2 of 102 mmHg with FiO 2 of 30%.

COVID-19 is an emerging, rapidly evolving pandemic. Profound hypoxemia and acute lung failure, the main causes of death, are the prominent features of ARDS resulting in a subset of critical COVID-19 pneumonia patients. 1 Despite the wide use of MV, the mortality rate is as high as 80% in intubated populations. 8 ECMO has become an alternative therapy for prolonging patient life and allowing time for lung recovery, especially in severe ARDS resulting from COVID-19. 9-10 However, conventional ECMO is conducted under MV and sedation; various complications may emerge during prolonged MV and sedation, including pneumothorax, increased risk of infection, ventilator-induced lung injury, systemic inflammation, and neurological complications. [11] [12] In addition, pneumonia and ARDS caused by COVID-19 show an unusual pattern of disease progression. Lung inflammation and tissue destruction arise from the lower airways and involve the alveoli, and features of pulmonary edema and hyaline membrane formation cause a restrictive lung pattern. 13 In recent years, awake ECMO has been used in selected cases of ARDS and has proved 6 advantageous. The strong rationale for using awake ECMO over conventional mechanically ventilated ECMO is that awake ECMO avoids intubation and MV, results in minimal stress, has no synchronization issues, and requires no sedatives. These parameters help avoid complications such as ventilator-induced lung injury, ventilator-associated infections, and delirium secondary to prolonged sedative usage. While providing time for lung recovery, awake ECMO permits spontaneous breathing, self-feeding, and active functional rehabilitation, which are all essential for post-ECMO recuperation. 4 In our case, the premature extubation caused the gradual deterioration of pulmonary function, suggesting that inflammation persisted even after four days of respiratory support.

The indications to initiate ECMO in COVID-19 have been suggested in a previous publication; namely, PaO 2 /FiO 2 of < 50 mm Hg for three hours or more, PaO 2 /FiO 2 < 80 mm Hg for six hours or more, or an arterial pH of less than 7.25 with a PaCO 2 of ≥ 60 mmHg for 6 hours. 14 In the present case, after re-intubation and respiratory support for 24 hours, profound hypoxemia was still evident, which prompted the initiation of V-V ECMO. Subsequently, an awake ECMO strategy was adopted. After extubation, the patient was able to communicate with her relatives and medical staff, and to feed herself the following day. Throughout the duration of her treatment under awake ECMO, early physiotherapy was initiated with passive and active movements progressing to daily ambulation without obvious discomfort. Alongside, preventive strategies and Class III precautions as recommended for ECMO in COVID-19 were followed.

The medical team donned face shields and disposable drapes in addition to the surgical masks and gloves, as recommended by the Chinese Society of Anesthesiology. 15 

Clinical predictors of mortality due to COVID-19 based on an analysis of data of 150 patients from Wuhan, China

Clinical Characteristics of Coronavirus Disease 2019 in China

Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome

Awake" extracorporeal membrane oxygenation (ECMO): pathophysiology, technical considerations, and clinical pioneering

Better be awake"-a role for awake extracorporeal membrane oxygenation in acute respiratory distress syndrome due to Pneumocystis pneumonia

Six-Month Outcome of

Immunocompromised Patients with Severe Acute Respiratory Distress Syndrome Rescued by

Extracorporeal Membrane Oxygenation. An International Multicenter Retrospective Study

Awake and fully mobile patients on cardiac extracorporeal life support

Clinical course and outcomes of critically ill patients with SARS

CoV-2 pneumonia in Wuhan, China: a single-centered, retrospective, observational study

COVID-19, ECMO, and lymphopenia: a word of caution

Extracorporeal Membrane Oxygenation -Crucial Considerations during the Coronavirus Crisis

Contemporary approaches in the use of extracorporeal membrane oxygenation to support patients waiting for lung transplantation

Clinical Management of Venoarterial Extracorporeal Membrane Oxygenation

Pathological findings of COVID-19 associated with acute respiratory distress syndrome

Extracorporeal Membrane Oxygenation During the

Coronavirus Disease 2019 Pandemic

Anesthesia Considerations and Infection Precautions for Trauma and Acute Care Cases During the COVID-19 Pandemic: Recommendations From a Task Force of the Chinese Society of Anesthesiology

The use of awake ECMO in critically ill patients who respond poorly to MV may be a promising therapeutic strategy for managing patients with ARDS due to COVID-19 pneumonia. However, this warrants further investigation.

The authors have no conflicts of interest to disclose.

Informed consents were obtained for publishing the details of the report and the photograph. 8