Which procedures put healthcare workers at greatest risk of COVID-19?

Several medical procedures—such as mechanical ventilation, autopsies, and bronchoscopies—generate aerosols and come with a high risk of transmitting the novel coronavirus disease (COVID-19) to healthcare workers, according to a recent study.

“[S]ome clinically relevant procedures received surprisingly little mention in our source documents,” the researchers said, adding that there still is a substantial number of procedures on which the literature is conflicting. Efforts to come to a consensus on these matters are needed.

Through a rapid systematic review of the Medline and Cochrane Central databases, the researchers identified nearly 40 groups of medical procedures that were classified as aerosol-generating. A total of 128 studies were eligible for the review and used as reference for this procedure list. [BMJ Open Respir Res 2020;7:e000730]

Fourteen procedure groups held very strong consensus regarding their potential to generate disease-transmitting aerosols, with more than 90 percent of the source documents agreeing. An additional three procedures saw strong consensus, with ≥80 percent agreement from the source documents.

These procedures included autopsies, intubation and extubation, mechanical and manual ventilation, cardiopulmonary resuscitation, airways suctioning, nebulized or aerosol therapy, chest physiotherapy, and sputum induction.

When performing these procedures, interventions and modifications should be in place to minimize the risk of COVID-19 transmission. Better air ventilation and humidity control could contribute toward this end, as well as the use of personal protective equipment and other containment devices.

The researchers also identified medical procedures in which aerosol-generating potential still remained under debate. Oral and dental procedures almost met the threshold, garnering 78-percent consensus among the source documents. Others, such as upper gastrointestinal endoscopy, thoracic surgeries, and nasopharyngeal and oropharyngeal swabbing, saw a more conflicted literature.

For these procedures, “we recommend that a process of achieving expert consensus be used, such as a modified Delphi method among a panel of relevant experts who [will] examine each of our 34 sources individually,” supplemented by an independent literature search, the researchers said.

They also pointed out that there remains a substantial list of procedures with very little information (fewer than 10 relevant documents) regarding their aerosol-generating potential. Some of these, such as colonoscopies and procedures related to birth, are very common medical procedures and should be addressed.

“It is possible that our search missed specialist publications, so a logical next step would be more specific searches for these procedures,” the researchers said. “If dependable literature addressing these cannot be identified, we recommend that professional and regulatory bodies note the list of procedures … and hold meetings to establish the current level of multidisciplinary professional consensus.”