Safe operation of the nuclear medicine department during the Covid-19 surge in NYC

Since its foundation in 1884 as the “Montefiore Home for Chronic Invalids”, Montefiore Medical Center has grown into a large academic-based medical institution in New York City, spanning several teaching hospitals in the Bronx. It offers medical care in one of the most population-dense counties in the United States. Its Division of Nuclear Medicine has grown alongside the subspecialty to become a well-regarded and established provider of  radionuclide-based diagnostic imaging studies and treatment for patients referred from diverse specialties. The Division offers a full array of PET-based, general, cardiovascular, and therapeutic procedures and has been very involved in promoting and documenting efficacy of classic nuclear medicine modalities, such as lung scintigraphy for the diagnosis of pulmonary embolism, and various functional imaging studies for the diagnosis of gastrointestinal motility disorders. The Division participates in training of radiology residents and cardiology fellows and has its own nuclear medicine residency program which contributes to its legacy of academic accomplishments.

In early 2020, the projected threat from the developing COVID-19 pandemic drove medical institutions in New York City to take rapid measures to protect the densely-populated metropolis, and their own institutions, from the then-novel and quickly-spreading coronavirus (SARS-CoV-2). At its earliest onset in the United States, the epicenter of disease was centered on the boroughs of New York City, at a time when definitive knowledge was scanty, testing was not available, and personal protective equipment (PPE) was lacking. In this short communication we would like to convey the efforts made to provide emergency care at our institution while both promoting the health of its patients and staff. The Division Head has responsibility to the patients, staff and trainees and must make decisions aligned with direction from the institution.

At the onset of initial cases, Montefiore Medical Center began to defer non-urgent diagnostic examinations which, of their own accord, had markedly decreased in volume due to a downstream effect of reduced general clinic visits and elective surgery. Screening temperature checks were implemented for patients upon entering a medical facility and patients were provided with a mask and required to fill out a short questionnaire screening for risk factors of exposure. Initial measures to control the risk of cross-infection included physical distancing in our waiting areas where seats were separated by six feet (1.8 m) from each other following recommendations from the Centers for Disease Control and Prevention (CDC) (1). Plexiglass barriers were installed between clerks and patients where possible.

The number of personnel in each independent medical examination and scanning room was limited to the minimum required for each intervention, patient interview, or procedure performed. These rooms were terminally disinfected after each patient and the use of PPE was encouraged among our staff by promoting awareness of personal safety and expanding accessibility to face shields and surgical and N95 masks. With careful rationing of PPE instituted by the medical system and internal conservation of resources, we had sufficient supplies to meet a greatly reduced demand. Ultimately, rules mandating the wearing of masks and faceshields were developed to govern appropriate staff behavior.

In the pandemic surge, before availability of antigen tests to establish infection or antibody tests to establish immunity, all patients were considered potentially infectious even without travel or exposure history, or typical symptoms, and precautions were taken to minimize potential for person-to-person spread. Beyond that, specific procedures with spread of aerosols or droplets potentially containing infectious material were considered high risk and efforts were made to avoid their performance (2). Leakage of radiopharmaceutical from devices used to create radiopharmaceuticals for ventilation scintigraphy had been previously studied in the context of employee dosimetry and it was known that a certain amount of activity is often released into the room air (3-6); for these reasons we therefore attempted to avoid ventilation scintigraphy over concern for escape of patient secretions into the air (7,8). Indeed, this is a valid concern as many symptoms of COVID-19 infection overlap those of PE including cough, shortness of breath, hypoxia and even hemoptysis. We therefore proposed an algorithm in which ventilation scintigraphy was not performed, and perfusion scintigraphy alone was used as a screening tool (9). When no significant defects were present, the patient was deemed free of embolism while if segmental perfusion defects were noted, further testing was indicated (such as CTPA or lower extremity doppler ultrasound in patients with lower extremity manifestations). Completion V/Q could be performed in those patients with contraindications to CTPA, with careful aerosol precautions and followed by terminal room decontamination.

As a teaching institution, our department is frequented by trainees and fellows, both from within and outside of our Division.  Attending physicians and trainees traditionally work  side-to-side however in the COVID- 19 period, new paradigms for teaching had to be developed. To accomplish this, we adopted a “one workstation, one person” rule. Stations were now to be cleaned daily, and not shared during the course of a rotation. To the extent possible, clusters of workstations were dispersed, and the attending physicians’ computers were configured to read and dictate studies, either within hospital offices, or from home, to the extent that that was allowed. An effort was made to elaborate minimum standards for monitors used to review nuclear medicine studies, something that was heretofore not clearly defined (10). Review (and teaching) sessions were implemented initially over Skype for Business, and subsequently over Teams (both Microsoft Corporation, Redmond, WA), fully supported on our enterprise-based equipment (11). Paradoxically, attending meetings virtually has eliminated travel time and increased the ability of staff to participate in group rounds and teaching. It has also lowered the bar and allowed us to invite national and international speakers to address our local group.

As the incidence of COVID-19 started decreasing in New York in mid-2020, our outpatient volumes have begun a recovery towards the “pre-COVID” volumes. Important cross-infection prevention measures remain in place including the use of masks, and screening for fever and other symptoms in addition to questionnaires to detect patients at risk from prior exposure to SARS-CoV-2 Ventilation and perfusion scintigraphy studies have undergone further adjustments: Patient charts are reviewed to determine COVID-19 status before protocolling these studies. “Complete” V/Q scans are performed in patients with a recent negative nasopharyngeal swab and full-dosage perfusion-only scintigraphy for those with recent positive nasopharyngeal swabs and/or moderate to high clinical concern. Lastly, low-dosage perfusion only scintigraphy is performed in patients with absent/pending swabs but low-risk of infection, with the option of subsequent completion V/Q scan immediately following perfusion, if needed.

The sudden adaptations we have innovated in response to the unexpected challenges of this pandemic have altered the way be run our divisions, specifically moving the medical field into relying more on connecting virtually. Some of these measures, borne of necessity, may be worth maintaining even follow resolution of the COVD- 19 pandemic.

1. Centers for Disease Control and Prevention. Coronavirus (COVID-19). http://www.cdc.gov/coronavirus/2019-ncov/index.html. Accessed 10/18/2020.
2. National Center for Immunization and Respiratory Diseases (NCIRD) DoVD. Interim Infection Prevention and Control Recommendations for Patients with Suspected or Confirmed Coronavirus Disease 2019 (COVID-19) in Healthcare March 10, 2020; https://www.cdc.gov/coronavirus/2019- ncov/infection-control/control-recommendations.html. Accessed March 17, 2020.
3. Williams DA, Carlson C, McEnerney K, Hope E, Hoh Technetium-99m DTPA aerosol contamination in lung ventilation studies. J Nucl Med Technol. 1998;26:43-44.
4. Achey B, Miller K, Erdman M, King Potential dose to nuclear medicine technologists from 99mTc-DTPA aerosol lung studies. Health Phys. 2004;86:S85-87.
5. Brudecki K, Borkowska E, Gorzkiewicz K, Kostkiewicz M, Mróz 99mTc activity concentrations in room air and resulting internal contamination of medical personnel during ventilation–perfusion lung scans. Radiation and Environmental Biophysics. 2019;58:469-475.
6. Mayes Safe practice ventilation technique in lung scanning for pulmonary embolism. Nucl Med Commun. 2020.
7. Lam WW, Loke KS, Wong WY, Ng Facing a disruptive threat: how can a nuclear medicine service be prepared for the coronavirus outbreak 2020? Eur J Nucl Med Mol Imaging. 2020.
8. Zuckier LS, Gordon SR. COVID-19 in the Nuclear Medicine Department, be prepared for ventilation scans as well! Nucl Med Commun. 2020;41:494-495.
9. Zuckier LS, Moadel RM, Haramati LB, Freeman LM. Diagnostic Evaluation of Pulmonary Embolism During the COVID-19 J Nucl Med. 2020;61:630-631.
10. Song N, Zuckier A dearth of specifications regarding primary diagnostic monitors (PDMs) for nuclear medicine leaves us with little guidance during the COVID 19 pandemic. J Appl Clin Med Phys. 2020.

Moadel RM, Zamora E, Burns JG, et al. Remaining Academically Connected While Socially Distant: Leveraging Technology to Support Dispersed Radiology and Nuclear Medicine Training Programs in the Era of COVID-19. Acad Radiol. 2020;27:898-899.