A 48-year-old man was admitted to a national tertiary hospital in Hanoi, Vietnam, with fever, cough, and shortness of breath. The patient was a member of medical staff in a TB hospital in the northeastern part of Vietnam. Four days before admission to our hospital, he had a fever, cough, and sputum. He was administered amoxicillin 2 g/day in his hospital. In the next day, his condition deteriorated and he developed dyspnea. In the next day, he visited and was hospitalized in a local general hospital, and was diagnosed with bacterial pneumonia. He was started to support with non-invasive mechanical ventilation (3 days prior to the admission to our hospital) and treated with Ceftriaxone (2 g/day). However, his respiratory condition deteriorated. At that time, computed tomography (CT) scans showed bilateral diffuse consolidation (Fig. 1a). He had diabetes mellitus, chronic gout, and long-term use of corticosteroids.
At the time of admission to the emergency department in our hospital, a physical examination showed that the patient's body temperature was 38.5  C and blood pressure was 100/60 mmHg. Arterial blood gas analysis showed that the ratio of partial pressure of arterial oxygen to the fraction of inspired oxygen (PaO2/FiO2) was 50 mmHg and lung compliance was 12 mL/cmH2O (Table 1). Laboratory findings at the time of admission were shown in Table 2. After the admission of Emergency department, noninvasive ventilation was applied; however, after 6 h, no improvement has been seen in the patient's condition. The patient was intubated for the mechanical ventilation based on the methods by the ARDS Net, then given prone position. Despite the volume-controlled ventilation (VCV) support in the Emergency Department, his respiratory condition deteriorated. In the 2nd day of admission, he was transferred to the intensive care unit (ICU).
Upon arrival at the ICU, he had a blood pressure of 110/60 mmHg, heart rate of 102 beats/min, Oxygen saturation (SpO2) of 80%, central venous pressure of 10 mmHg, and Murray score for lung injury of 4. A chest X-ray showed bilateral infiltration (Fig. 2a). A lung ultrasound examination showed no pleural fluid. At the same day, Mycobacterium tuberculosis was detected in a sputum smear for acid-fast bacilli (AFB +++). Human immunodeficiency virus was not detected in the blood using the real-time polymerase chain reaction. Based on these physical examination, laboratory findings, chest images, and respiratory conditions, he was diagnosed with TB-induced ARDS. The discussion among the healthcare team was made to proceed to VV-ECMO. VV-ECMO was then initiated with internal jugular vein and femoral access vein cannulation by the Seldinger technique, with blood flow at 4.5 L/min and gas flow at 4.2 L/min. The mechanical ventilator setting and parameters were as follows: tidal volume (Vt), 4 mL/kg; end inspiratory plateau pressure (Pplat), <25 cmH2O; respiratory rate (RR), 8 breaths/min, positive end-expiratory pressure (PEEP), 14 cmH2O, and FiO2, 1.0. Anti-TB regimens were also initiated with ethambutol (1600 mg), pyrazinamide (1500 mg), and rifampicin/isoniazid (600 mg/400 mg). Regarding the administrations of antibiotics, Levofloxacin (750 mg) were administered for the first three days, then meropenem (1000 mg) and amikacin (1000 mg) were administered for 14 days. Corticosteroids (100 mg of hydrocortisone/8 h) was also administered. In terms of anticoagulation regimen, heparin was applied for preventing the development of thrombosis at oxygenation membrane. The 100 IU/kg of dose of intravenous bolus dose was given when cannulas insertions were finished, then 10 IU/kg/hour as the maintaining dose. Activated Partial Thromboplastin Time was tested every 4-6 hours for monitoring heparin anticoagulation effect and was kept from 45 to 55 seconds. The patient had no any bleeding and oxygenation membrane was maintained well in the process.
After initiation of ECMO support, the patient's hypoxemia rapidly improved to 216 mmHg of PaO2/FiO2 and lung compliance was improved to 26 mL/cmH2O on the 2nd day of ECMO support (Fig. 3). Chest radiography gradually improved on the 4th day of ECMO support (Fig. 2b and c). On the 5th day of ECMO support, the patient was weaned from ECMO, and PaO2/FiO2 and lung compliance were improved to >390 mmHg and 38 mL/cmH2O, respectively (Fig. 3). The patient was extubated at the 8th day after admission for ECMO.
On the 10th day after admission for ECMO, mechanical ventilation support was backed because of respiratory muscle weakness caused by corticosteroid-induced myopathy. A cerebrospinal fluid examination was normal. On the 15th day, tracheostomy was performed. On the 35th day, the patient was weaned from mechanical ventilation and discharged on the 47th day. Anti-TB regimens were continued after discharge from hospital.