Infection prevention concerns associated with radiological methods
The World Health Organization and the Norwegian Institute of Public Health have defined the means of infection of SARS-CoV-2 as droplet infection, while some procedures entail a risk of aerosol release which implies that the situation will be defined as airborne infection (5). Radiographers are exposed to infection through close contact with a large number of patients. Radiologists may be exposed through ultrasound and interventional activities.
Disinfection of radiological equipment can be complicated and time-consuming. If there is no visible spillage, contact infection procedures require that surfaces or points with which the patient and personnel have been in direct contact during the examination must be disinfected for three minutes with disinfection spirit. Visible spillage is disinfected with an approved disinfectant for the recommended time. If the patient has not worn a mask during the examination, the droplet regimen is used; i.e. disinfection of equipment and surfaces within a radius of two metres from the patient's face and which have been exposed to droplets for some time (several minutes). Equipment, inventory and surfaces that the patient has passed only briefly do not need to be disinfected unless there has been direct contact. Disinfection in connection with aerosol-generating procedures is the same as for airborne infection.
If several machines of similar kind are available, it is practical to allocate one to patients with droplet infection in order to shield the other activities. Sound procedures for transport of potentially infectious patients through the department, based on ventilation, the possibility of a screened entrance and use of different machines from those used for other activities are important. COVID-19 may make chest X-ray monitoring necessary in the observation ward and Intensive Care Department. We recommend that a portable X-ray unit be allocated to a defined infection cohort.
COVID-19 can also affect persons with other diseases. We must therefore be prepared to handle any diagnostic procedure, survey or intervention, also concurrently with SARS-CoV-2 infection. Droplet infection procedures have now become extra relevant in connection with angiography, MRI and nuclear medicine methods.
In some cases, asymptomatic COVID-19 will be suspected on the basis of findings from a pulmonary CT scan performed on another indication, for example in connection with cancer follow-up in the Department of Radiology or with PET/CT. To avoid lack of clarity concerning the management of the infection prevention regimen in relation to these patient categories, we strongly recommend that all hospitals plan for such situations.