New York, Jun 22 (IANS): Besides making use of personal protective equipment, healthcare workers need to avoid procedures that irritate airways and provoke violent coughing and try to reduce exposure to infectious aerosol while treating Covid-19 patients, say scientists, including one of Indian-origin.
If possible, health care providers should stay six feet away from infected patients, especially when the patient is coughing or sneezing, said the article published in the American Journal of Respiratory and Critical Care Medicine.
In their recommendations to healthcare workers, the researchers suggested that when using a mechanical ventilator, they should institute barriers to filter the virus or reduce virus dispersion by placing a filter at the exhalation port of the ventilator or connecting a filter to the oxygen mask.
For spontaneously breathing patients, placing a surgical mask on the patient's face or using tissue to cover his or her mouth, especially during coughing, sneezing or talking, may reduce the dispersion distance or viral load.
While, ideally, infected patients should be in single rooms to prevent droplet dispersion, it is acceptable for two patients with the same infection that is spread by respiratory droplets to be in the same room, they added.
"Coughs and sneezes create respiratory droplets of variable size that spread respiratory viral infections. Because these droplets are forcefully expelled, they are dispersed in the environment and can be exhaled by a susceptible host," said co-author of the article Rajiv Dhand, Professor at University of Tennessee Graduate School of Medicine in the US.
"While most respiratory droplets are filtered by the nose or deposit in the oropharynx, the smaller droplet nuclei become suspended in room air and individuals farther away from the patient may inhale them.
In the article, Dhand and Jie Li, Associate Professor at Rush University Medical Center in the US described the various types and sizes of virus-containing droplets present in sneezes and coughs, the locations in the respiratory systems where they deposit, and how certain medical procedures and devices may spread these droplets and the risks for health care professionals.
"The apprehension about the use of aerosolised therapies in Covid-19 patients relates to their potential to spread infectious aerosols," said Dhand.
"Our recommendations offer a balanced, scientific perspective on the use of such aerosolised therapies in patients infected with SARS-CoV-2, the virus that causes COVID-19."
Airborne particles may be produced by various aerosol generating procedures (AGPs), such as suctioning or tracheal intubation, as well as by aerosol generators, especially jet nebulizers.
"AGPs such as intubation, bronchoscopy, physiotherapy and suctioning generate potential infectious bioaerosols by provoking coughs and are associated with increased infection rates among employees working in health care," stated the authors.
"In contrast, AGPs such as oxygen therapy, use of humidified high-flow nasal cannula, non-invasive ventilation and manual ventilation via mask are less about 'generating' bioaerosols and more about 'dispersing' aerosols further away from the patient."