What is The National Convalescent Plasma Project

Fact: The project has launched a website for patients who have recovered from COVID-19 and want to donate plasma, and for healthcare providers who are considering this treatment for their patients.

Doctors will be able to use the platform to input data on their patients’ response to the plasma treatment. The hope is that this potentially life-saving therapy can be moved to controlled clinical trials followed by wider use if effectiveness is shown as quickly as possible.

Peripheral lymphocytes are the key

According to a study published in The Journal of Infectious Diseases, peripheral lymphocyte subset alteration has been linked with the clinical characteristics and treatment efficacy of COVID-19.

Fan Wang, MD, Zhongnan Hospital of Wuhan University, Wuhan, China, and colleagues measured levels of peripheral lymphocyte subsets in 60 patients hospitalized with COVID-19, and found that total lymphocytes, CD4+ T cells, CD8+ T cells, B cells, and natural killer (NK) cells, decreased in patients with COVID-19, but severe cases had lower levels than milder cases.

Following treatment, 37 (67%) patients attained clinical response, with an increase of CD8+ T cells and B cells; however, no significant change of any subset was detected in patients who did not respond to treatment. In multivariate analysis, post-treatment decrease of CD8+ T cells and B cells and increase of CD4+/CD8+ ratio independently predicted COVID-19 severity and treatment efficacy.

Role of ultrasound in COVID-19

A study published in Echocardiography revealed that lung ultrasound can be used as a bedside tool for identification of lung involvement, along with pulmonary severity, in patients with suspected or documented COVID‐19, thus limiting the use of chest X-rays and CTs. A scan of the 3 different areas of the thorax, anterior, lateral, and posterior, and then superior and inferior segments were performed.

The authors noted that an experienced sonographer can do this examination within 5 minutes. For those who are not experienced, a brief training and about 25 supervised exams seem to be sufficient to achieve a basic ability to perform the lung ultrasound.

What is an empirical estimate of the serial interval

It is the time from illness onset in a primary case (infector) to illness onset in a secondary case (infectee).

NEJM: Early data suggest that SARS-CoV-2 infection is more likely to be transmitted than MERS-CoV infection because of a higher estimated reproductive number (2.2 vs. 0.9) and a shorter estimated serial interval distribution (7.5 days vs. 12.6 days). The mean interval (±SD) from symptom onset to diagnosis has been noted to be 4.3±4.1 days.

What are the 4 benchmarks for a return to normalcy

1. Hospitals must be able to safely treat all patients requiring hospitalization, without the need for crisis standards of care. This translates to having adequate beds, ventilators and staff.
2. Authorities must be able to test at least everyone who has symptoms, and to get reliable results in a timely manner.
3. Health agencies must be able to monitor confirmed cases, trace contacts of the infected patients, and have at-risk people go into isolation or quarantine.
4. There must be a sustained reduction in cases for at least 14 days. Because it can take up to two weeks for symptoms to emerge, any infections that have already happened can take that long to appear.

Pets can infect you

No. Nadia, a tiger at the Bronx Zoo in New York, tested positive for the virus. Your cat will probably not infect you, but experts suggest to take the same precautions around pets as you would do around people.

When to start oxygen

Society of Critical Care Medicine (SCCM) Surviving Sepsis Campaign guideline on management of critically ill adults with coronavirus disease 2019 (COVID-19) recommendations on ventilatory support:

Supplemental oxygen to be considered in patients with peripheral oxygen saturation (SPO2) < 92% (SCCM Weak recommendation, Low-quality evidence)

Supplemental oxygen to be started in patients with SPO2 < 90% (SCCM Strong recommendation, Moderate-quality evidence)

SPO₂ to be maintained no higher than 96% in adults with acute hypoxemic respiratory failure on oxygen (SCCM Strong recommendation, Moderate-quality evidence)

High-flow nasal cannula (HFNC) to be considered in patients with acute hypoxemic respiratory failure despite conventional oxygen therapy (SCCM Weak recommendation, Low-quality evidence)

HFNC is preferred over non-invasive positive pressure ventilation (NIPPV) (SCCM Weak recommendation, Low-quality evidence)

Trial of NIPPV with close monitoring and frequent assessment for worsening respiratory failure may be considered if HFNC is not available and there is no urgent indication for endotracheal intubation (SCCM Weak recommendation, Very low-quality evidence)

No recommendation can be made regarding helmet NIPPV compared to mask NIPPV; helmet NIPPV may be an option, but safety and efficacy are not clearly known in patients with COVID-19

Patients receiving HFNC or NIPPV to be closely monitored for worsening of respiratory status, with early intubation in case of worsening. (SCCM Best Practice Statement)

Dr KK Aggarwal

President CMAAO