On March 14th, 2020, a 66-year-old previously healthy male patient were referred to the isolation ward in Guanggu Branch of Hubei Province Maternity and Childcare Hospital. He has had a high fever and non-productive cough for twenty days. On March 4th, 2020, he visited a local clinic for his symptoms. His oropharyngeal swab specimen was collected there and tested positive with SARS-CoV-2 RT-PCR assays, along with the chest CT showing ground-glass opacity in both lungs, which indicated viral pneumonia. Then he was admitted to the local hospital and be given supportive therapy and accumulated 600 mg methylprednisolone in ten days. However, the shortness of the breath deteriorated while the SPO2 decreased to 85%-89% in the condition of non-invasive ventilation at the time of transferring. On examination, his temperature was 36.4° C, pulse 86/min, respiratory 21/min, and blood pressure 118/64 mmHg. Supportive care was then provided in the isolation ward and lab tests were performed also (table 1). On March 15th, the SPO2 decreased further (80%-85%) with high-flow oxygen therapy (60L/min). Arterial blood gas analysis showed pH 7.41, PO2 72 mmHg and PCO2 55 mmHg. Intubation and mechanical ventilation were administrated. 10 cmH2O positive end-expiratory pressure and 80% inspired oxygen were applied.
The next day, patient’s symptom of dyspnea and chest tightness deteriorated and norepinephrine infusion is required for maintaining normal blood pressure. Veno-venous Extracorporeal Membrane Oxygenation (ECMO) was initiated and the inspired oxygen was down-regulated to 40%. After the procedure, SPO2 increased to 98%-100% and BP 110/70mmHg. On March 19th, patient’s serum IL-6 was tested and the result revealed a significantly high IL-6 level. 400 mg intravenous Tocilizumab was administrated, however, the IL-6 level increased even more the following day (Figure 1 A). 400 mg intravenous Tocilizumab was repeated. At the same time, the patient also received Continuous VenoVenous HemoDiaFiltration (CVVHDF) treatment daily from March 19th to March 22nd in order to decrease the IL-6 level quickly. However, the bedside chest X-ray still revealed severe pneumonia and the clinical manifestations did not improve (Figure 2). The inflammatory cytokines were still at high level. Continuous renal replacement therapy (CRRT) protocol was changed to Double filtration plasma pheresis (DFPP) with a plasma separator (plasmaflow-08w, Asahi Kasei) and a plasma fractionator (EC-20W, Asahi Kasei) three times from 23rd to 25th before it returned to CVVHDF in 26th. The estimated plasma volume was set as 3L, the substitution fluid was albumin solution, blood flow rate 100mL/min, plasma flow rate in separator 30mL/min, and waste flow rate 3.0mL/min. From 16th to 25th March, the patients received multiple blood transfusion (including 400mL convalescent plasma) to compensate the volume loss caused by ECMO and CRRT bypass. At 25th, March, due to the anticipation of prolonged mechanical ventilation, tracheotomy was performed. With the time bought by ECMO and CRRT, patient’s homeostasis recovered, along with the recovering of chest imaging. At 27th, the ECMO discontinued according to the ECMO expert evaluation. The SPO2 kept 100% in the condition of mechanical ventilation after the ECMO discontinuation. Since the hemodynamics and blood gas improved, all the intravenous catheters were removed at March 28th. Supportive care continued for several days then the patient was been transferred to non-ICU isolation ward. The typical inflammatory markers during this period of time were shown in figure 1 while the D-dimer and platelet results should be interpreted with caution due to the anticoagulants use.