Q: Among patients who are positive in respiratory tract sample, are those patients also having positive stool tests?


Yes, we have detected the new coronavirus nucleic acid from the stool of some patients, but not every one.  

1.  Prior to respiratory symptoms--many patients reported diarrhea and abdominal discomfort. 

2.  COVID-19 has been isolated from feces of multiple patients in China.

3. Of 73 patients, 39 tested positive in the stool (10-78 years of age)

4. Duration of positive stool was 1-12 days. 

5. 17 patients remained positive in the stool even after negative respiratory samples

Q: Why is the foamy respiratory secretions believed to represent heart failure rather than viral inflammatory damage?


Autopsy of COVID-19 showed that the lungs are with varying degrees of consolidation. Serous fibrin exudate and hyaline membrane were seen in alveolar cavity. Focal hemorrhage and necrosis of lung tissue may occur by hemorrhagic infarction. Partial alveolar exudate is organized and interstitial fibrosis occurs. Thus, COVID-19 patients do not develop foamy respiratory secretions easily. Another hand, heart failure is definitely to be diagnosed in combination with clinical symptoms, such as foamy sputum, major physical examination and laboratory tests, etc.

Q: Why do you intubate with ECMO? Can’t you spare the intubation if you do VV ECMO? Would this not decrease the risk of health care exposure to virus?


When patients developed ARDS and respiratory failure, we applied intubation and mechanical ventilation but not ECMO first. You know, some patients do not need ECMO necessarily and finally recovered. Intubation and mechanical ventilation has another advantage of sputum aspiration (in a closed aspiration equipment) and maintain opening of alveoli, which ECMO could not provide. Although intubation increased risk of exposure, but it was just less than a minute and we were well protected with N95 mask, faceplate and head cover. On the contrary, VV ECMO totally abandoned lung and that’s not physiological. A COVID-19 patient with ECMO and mask-protected mouth and nose, was regard to have higher risk for health providers than intubated patients (personal opinion).

Q: We also are seeing in our first patients who are in intensive care on ventilators that they are staying clinically at the same place for days- no improvement like we would see with bacterial pneumonia. In your experience


Yes, I share your concerns. I had a patient with a prolonged clinical course. He was on a non-invasive mechanical ventilator for about 30 days. At that time he had severe respiratory failure so that he couldn’t eat without the ventilator. Afterwards, we gave him enteral nutrition to reduce the weaning time as much as possible. After 10 days, we stopped the anti-virus medicine arbidol, prescribed only steroid and intravenous immunoglobulin, gradually he had no fever, and was weaned from respiratory support. Because he was 57 years old and strong, he was able to expectorate and clear his own secretions. As a side note, sputum of COVID-19 patients is very sticky and can’t be expectorated easily. We were thankful to be able to avoid intubation, which would increase the risk of ventilator-related injuries. So in summary, this virus infection is a self-limited process.  During the process, mechanical ventilation is a tool to help the patients get through the acute danger of respiratory failure. With time, respiratory function should begin to improve, and the ventilator can be weaned gradually. So in my opinion, anti-virus medications are not the most important treatment. And up to this point, the results of remdesevir research haven’t been convincing. 

Q: It has been said the mortality of severe patient is > 60%. How is the patient that survives the illness? Do they need special care like tracheostomy, feeding tubes, dialysis? In other words how is quality of life?


It is hopeful that the mortality of severe patients will be cut down to less than 50% through strengthening nursing, increasingly effective treatment options and prevention with vaccines. However, in answer to your question, we found that in the patients who survived the illness, their respiratory and renal function returned to baseline as the hypoxia corrected. Of course, in patients with preexisting chronic renal failure there was ongoing need for dialysis. There were a small number of  isolated patient cases with residual pulmonary fibrosis who have had some chronic respiratory insufficiency and needed oxygen treatment occasionally.  

Q: When would you consider Angiogram in MI II, and what measures of hemodynamic support would you consider such as Impala or IABP?


Increased serum troponin I/T concentrations without recognizable acute coronary syndromes are well described in critically ill and deceased cases. We will not perform coronary angiogram for patients with Tape 2 MI. For COVID-19 patients who concomitant or complicated with STEMI or NSTEMI, if the patients without respiratory failure but the hemodynamic status is unstable, IABP is preferred. If the patients have respiratory and circulatory failure, V-A ECMO is routinely used. For a few patients who had respiratory failure complicated with fulminant myocarditis, ECMO combined with IABP was used.

Q: On ECMO, were you using ultrafiltration or hemodialysis?


Yes, in part of cases. It was used in acute kidney injury patients or patients who needed to cytokines elimination.

Q: The gender ratio could be affected by smoking history? Since there are more males have smoking history as compared to females hence their lungs are more compromised?


a) Differences in COVID-19 disease prevalence and severity are associated with sex, and smoking is related to higher expression of ACE2 (the receptor for severe acute respiratory syndrome coronavirus 2 [SARS- CoV-2]), so that might also be a factor. 

b) One preprint study ( DOI:10.1101/2020.01.26.919985), using single-cell sequencing, found that expression of ACE2 was more predominant in Asian men, which might be the reason for the higher prevalence of COVID-19 in this subgroup of patients than in women and patients of other ethnicities. 

c) One study of 140 patients with COVID-19 in China (DOI:10.1111/ all.14238), found the sex distribution equal; whereas, in a study of critically ill patients (https://doi.org/10.1016/S2213- 2600(20)30079-5), more men were affected (67%) than women. 

d) In a latest report (DOI:10.1056/NEJMoa2002032) of 1099 patients with COVID-19 from 552 hospitals in 30 provinces in China, 58% of the patients were men. 

Taken together, these data seem to indicate that there might be a sex predisposition to COVID-19, with men more prone to being affected.

This sex predisposition might be associated with the much higher smoking rate in men than in women in China (288 million men vs 12·6 million women were smokers in 2018). Of note, one study (preprint)( Cai G. medRxiv 2020) found that although ACE2 expression was not significantly different between Asian and white people, men and women, or subgroups aged older and younger than 60 years, it was significantly higher in current smokers of Asian ethnicity than Asian non-smokers; although no difference was found between smokers and non-smokers who were white. Nonetheless, the current literature does not support smoking as a predisposing factor in men or any subgroup for infection with SARS-CoV-2. In the study by Zhang and colleagues, only 1·4% of patients were current smokers, although this number was much higher at 12·6% in the study by Guan and colleagues. The relatively small proportion of current smokers in each of these two studies compared with the proportion of male smokers in China (50·5%) are unlikely to be associated with incidence or severity of COVID-19. A trend towards an association was seen between smoking and severity of COVID-19 in the study by Zhang and colleagues (11·8% of smokers had non-severe disease vs 16·9% of smokers with severe disease), but it was not significant. Without strong evidence of an association between smoking and prevalence or severity of COVID-19 in Asian men compared with other subgroups, no firm conclusions can be drawn. With more cases being examined from different ethnic and genetic backgrounds worldwide, ACE2 expression variation can be better analysed and compared to establish whether it contributes to susceptibility to COVID-19 across the different subgroups.

Q: What is your experience with ECMO? When did you decide to use ECMO for COVID-19 patients?


1. When FiO2 > 90%, oxygenation index is less than 80mmHg, lasting for more than 3-4 hours; 2. airway platform pressure ≥ 35cmH2O.