Oncological imaging during COVID-19 pandemic

Cancer patients, because of their systemic immunosuppressive state caused by the malignancy and anti-cancer treatments, are more susceptible to COVID-19. Thus, there is an immense need for prevention and precaution during oncological imaging, along with a psychological support, writes Dr Bagyam Raghavan, Senior Consultant Radiologist, Apollo Cancer Institute, Chennai

The COVID-19 pandemic has imposed on clinicians a scenario never seen before where accepted guidelines and norms of treatment are challenged because of the tremendous strain on healthcare resources. Based on the clinical evidence that has emerged over the last few months, various guidelines have been released by the Government of India, Indian Council of Medical Research (ICMR), Association of Surgeons of India (ASI) and international bodies like the World Health Organization (WHO), European Society for Medical Oncology (ESMO) and National Institutes of Health (NIH). However, this is a dynamic process and is likely to be ever changing as we learn more about living with the pandemic and local variables.

Cancer patients, because of their systemic immunosuppressive state caused by the malignancy and anti-cancer treatments, like chemotherapy, targeted therapy and immunotherapy, are more susceptible to COVID-19 and have a higher incidence of life-threatening events such as severe pneumonia, acute respiratory distress syndrome and cytokine storm, causing multi-organ failure and death. According to a WHO report, cancer patients have an estimated two-fold increased risk of COVID-19 than the general population.

 Indian scenario

There is a steady rise in the number of COVID-19 cases across India and the Government of India has imposed a lockdown, along with suspending all tourist visas since March 2020. Most of the reported cases in the country are from six mega cities with increased population density – Mumbai, Delhi, Ahmedabad, Chennai, Pune and Kolkata. There is variable geographical distribution of cases resulting in government-imposed containment zones and travel restrictions consisting of three zones.

• Red zone (hotspots) – districts with high doubling rate and high number of active cases.
• Orange zone (non-hotspots) – districts with fewer cases.
• Green zone – districts without confirmed cases or without new cases in last 21 days.

 Guidelines for patient prioritisation for treatment and imaging

Imaging is mandatory before initiating any definitive treatment. Therefore, it is important to triage patients requiring immediate attention while re-scheduling non-urgent radiology care. A tiered plan, which prioritises patient care for, may be considered as follows:

• Priority A: urgent and immediate care
• Priority B: non-urgent, time-sensitive care may wait for a short interval
• Priority C: elective care, screening, research and imaging trials

In regions where the number of cases is high (red zone areas, containment areas), it is recommended that category C patients be postponed. Increased precautions should be taken surrounding in-person visits/treatments for patients with co-morbidities and a high risk of COVID-19 complications. Wherever possible, teleconsultations are encouraged including virtual tumour boards. The guidelines for category C patients can be implemented in green zones and selected orange zones by prioritising most to least urgent.

Safe environment

The principle method of transmission of the virus SARS-CoV-2 is droplet or direct/indirect contact transmission through fomites from symptomatic and asymptomatic carriers. Healthcare establishments, especially, imaging departments can become hotspots for infecting patients as well as healthcare professionals. Healthcare workers on frontline are at a greater risk of contracting infection and have had severe/critical infection with mortality. Other factors that need consideration are the resources available, and the ever-changing prevalence and transmissibility of COVID-19. Hence, a good dictum to follow is to consider all patients as COVID -19 positive. Thus, all staff must protect and sanitise themselves and their equipment, and maintain social distance. A systematic review and meta-analysis published in the Lancet says that an optimum distance of one metre and the use of face masks and eye shields protect against person-to-person virus transmission.

COVID-19 checklist for patients and attenders entering the facility:

• Mandate imaging only after clearing screening
• Ensure social distancing
• Limited staff for each patient
• PPE for staff and patients
• Cleaning and disinfecting after each patient
• History of contact with a proven COVID patient
• History of sick contact at home or in workplace
• History of travel (international/domestic) since travel is being permitted
• History of presence in a crowded place – social, religious gatherings, functions, etc.

If anyone is positive, involve the physician on call or the infectious disease department.

Personal Protective Equipment (PPE)

• Brief interaction with masked patients remains low-risk. Keeping patients masked is the most important step one can take; you could consider giving visor as well to symptomatic patients.
• Diagnostic imaging is a non-aerosol-generating procedure and healthcare worker here is at lower risk.
• Sessional: Face mask – surgical (FFP3 or FFP2), eye-shields /visor
• Single use for each patient: hand hygiene, gloves (nitrile better than rubber as they are chemical-resistant and hypo-allergic) and plastic aprons (full-sleeve gowns), caps. Interventional procedures in ICU and in operating theatre are aerosol-generating and considered high-risk and need full PPE
• Donning and doffing rules and appropriate disposal/decontaminating of PPE in appropriate bins must be followed strictly

Cleaning and disinfecting

SARS-CoV-2, the causative virus of COVID-19 can remain active on surfaces for several days. Hence, cleaning and disinfection is of utmost importance to prevent transmission by fomites. This is needed to prevent spread by fomites. The disinfection is more stringent in a known COVID -19 scan.

Every patient must be made to sanitise the hands and wear a mask (ideally surgical mask) before entering the imaging room.

Create a green corridor so that patient comes in and out as soon as possible

• Disinfection in a known COVID scan:
• After scan, disinfect surfaces with alcohol or quaternary ammonium compound-based disinfectant/wipes ; disinfection of different machines will depend on equipment manufacture guidelines covered in the specific sections
• Mop floor from periphery to centre with one per cent sodium hypochlorite or phenol- based disinfectant
• Some practices also fumigate with hydrogen peroxide vapour or use UVC light as a supplement. This is not a necessary step, but may be done, if available. Do not fumigate with sodium hypochlorite or quaternary ammonium compounds.
• Scanners may be kept unused for upto one hour/six cycles of ventilation after the scan. Count from the time the patient leaves the imaging room.
• This is particularly important following high-risk procedures like aerosol- generating procedures or interventions, or if an unmasked patient was scanned/coughed.
• For other procedures, disinfecting surfaces for approximately 20 minutes (to allow enough contact time and drying time) may be acceptable, if there are workflow issues with waiting longer.
• These steps need not be followed while imaging consecutive known COVID patients.

• Disinfection after every patient:
• Disinfect equipment and workstation between patients and users, respectively is mandatory. It is necessary to disinfect the parts of the equipment that come in contact with the patient during studies ( X-Ray table, mammography compression plate, CT gantry, ultrasound equipment transducer cable, transducer-resting stands and handle bars, the keyboard, touch screen, monitor, etc.) after every patient with vendor-approved disinfectant alcohol or quaternary ammonium compound-based disinfectant/wipes and change the linen/sheet. MRI gantry, table, infusion pump and coil should also be cleaned by vendor-approved disinfectant and care should be taken that the plugs and RF pins are not wet before use.
• The imaging room floor should be sanitised using three-bucket procedure (detergent, water and one per cent sodium hypochlorite solution.)

• Social distancing:
• The aim of this is to minimise the dispersal of respiratory secretions, reduce both direct transmission risk and environmental contamination.
• Social distancing of one metre is to be maintained in clinical areas, communal waiting areas and during transportation; it is recommended that all patients and possible or confirmed COVID-19 cases wear a surgical face mask. Allow a maximum of one attender per patient. A cloth mask must be worn by attenders.

Psychological support during COVID-19 pandemic

Psychological support needs to be provided to patients and staff during these anxious provoking times of COVID-19. Oncological patients are emotionally vulnerable because of the nature of their disease and the side-effects of treatment, and feel stigmatised. This can be addressed by phone calls and teleconsultation with exclusive hotlines. Support groups can help in this essential emotional and psychological support.

Healthcare workers may experience considerable psychologic distress as a result of the COVID-19 pandemic. Staff should be reassured, educated and appreciated. Online counselling like WhatsApp groups will allow delivery of psychosocial supports, while preserving physical distancing. Appointing team leaders to co-ordinate with the departmental head and human resource department will help in giving support and empathy.

Conclusion

The only practical solution appears to be protecting healthcare workers and the community against COVID-19 infection and transmission and having treatment strategies which protect the vulnerable patient and offers them a realistic chance for survival. The use of hospital resources such as PPE, decreasing appointments and lowered staff strength also plays an additional burden on the financial resources and this must be managed efficiently.