Development and execution of a pandemic preparedness plan: Therapeutic medical physics and radiation dosimetry during the COVID‐19 crisis

Abstract The SARS‐CoV‐2 coronavirus pandemic has spread around the world including the United States. New York State has been hardest hit by the virus with over 380 000 citizens with confirmed COVID‐19, the illness associated with the SARS‐CoV‐2 virus. At our institution, the medical physics and dosimetry group developed a pandemic preparedness plan to ensure continued operation of our service. Actions taken included launching remote access to clinical systems for all dosimetrists and physicists, establishing lines of communication among staff members, and altering coverage schedules to limit on‐site presence and decrease risk of infection. The preparedness plan was activated March 23, 2020, and data were collected on treatment planning and chart checking efficiency for 6 weeks. External beam patient load decreased by 25% during the COVID‐19 crisis, and special procedures were almost entirely eliminated excepting urgent stereotactic radiosurgery or brachytherapy. Efficiency of treatment planning and chart checking was slightly better than a comparable 6‐week interval in 2019. This is most likely due to decreased patient load: Fewer plans to generate and more physicists available for checking without special procedure coverage. Physicists and dosimetrists completed a survey about their experience during the crisis and responded positively about the preparedness plan and their altered work arrangements, though technical problems and connectivity issues made the transition to remote work difficult. Overall, the medical physics and dosimetry group successfully maintained high‐quality, efficient care while minimizing risk to the staff by minimizing on‐site presence. Currently, the number of COVID‐19 cases in our area is decreasing, but the preparedness plan has demonstrated efficacy, and we will be ready to activate the plan should COVID‐19 return or an unknown virus manifest in the future.


| INTRODUCTION
The novel SARS-CoV-2 coronavirus was first detected in Wuhan, China, in December 2019. The first case of COVID-19, the disease associated with the SARS-CoV-2 coronavirus, was diagnosed in the United States on January 20, 2020. The disease is primarily spread through respiratory droplets and close contact. 1 Symptoms of COVID-19 included fever, cough, shortness of breath, fatigue, muscle or body aches, headache, loss of taste or smell, sore throat, congestion or runny nose, nausea or vomiting, and diarrhea. 2 Individuals with existing comorbidities such as hypertension, diabetes, and obesity are at increased risk for severe complications. 3 Many people infected with the SARS-CoV-2 virus, however, remain asymptomatic 4 and could unwittingly transmit the virus to others. Since the first diagnosis in January, the virus has spread to every state, infected In addition to the acute effects of the virus itself, COVID-19 has impacted all aspects of medical care including oncological care. Two studies from China found that cancer patients are more susceptible to contracting the virus. 5,6 One of these found that cancer patients experience worse outcomes than patients not undergoing cancer treatment. 6 Radiation oncology departments present a particular challenge for restricting the spread of infectious disease due to daily treatments, full waiting rooms, and common equipment used by multiple patients such as the linear accelerator treatment couch. 7 Recent publications from China, 1 Singapore, 8 and Italy 9 have relayed some of the challenges associated with treating cancer patients during the COVID-19 pandemic, but few have discussed the specific issues regarding medical physics support.
Northwell Health is a large health system with hospitals and clinics spread throughout the greater New York area, including the five boroughs of New York City, Long Island, and Westchester county.
Northwell has treated thousands of COVID-19 patients in the epicenter of the outbreak in the United States and recently published observations and outcomes for approximately 5700 patients. 3 The Department of Radiation Medicine is localized to several key hospitals and outpatient centers in a variety of geographic locations in the health system. The administration and medical faculty acted quickly to develop contingency plans to ensure the continued safe operation of our department should an outbreak occur. The medical physics and dosimetry groups were tasked with developing pandemic operating procedures to ensure consistent quality of treatment while preserving staff safety and health. As the virus spread through downstate New York in early March, pandemic contingency plans were activated in our department. We continued to treat our patients, some of which were COVID-19 positive.
The purpose of this manuscript is to describe the physics and dosimetry pandemic preparedness plan at our institution and assess its efficacy during the 2020 COVID-19 pandemic. The benefits of this retrospective analysis are threefold: First, to share information from an early "hot spot" of the epidemic with our colleagues should they need to prepare; second, to consider our ad hoc readiness policies and procedures for more permanent adoption should COVID-19 (or another pandemic) strike again; and third, to reflect on the potential evolution of large, multisite medical physics and dosimetry work as glimpsed during an extraordinary worldwide event.

| MATERIALS AND METHODS
The first case of COVID-19 in New York was diagnosed March 3, 2020 in New Rochelle, a small city in Westchester county close to New York City. It was at this time that the department began preparing in earnest for significant disruption of normal clinical activities.
The departmental administration identified five priorities to consider when developing contingency plans for said disruption: (a) Actively manage staff, (b) decrease treatment volume, (c) implement telehealth, (d) encourage multidisciplinary discussion, and (e) maintain a culture of safety. 10 Medical faculty made several significant changes to reflect these priorities and reduce the potential for hospitalization. 11 Reduction of patient volume was accomplished by prioritizing care into three categories: Priority I, II, and III. As described by Chen et al., 11 "Priority I" cases required radiation therapy most urgently, where loss of life, progression of disease, or permanent loss of function was possible.
Examples included oncologic emergencies or advanced disease. "Priority II" cases could be delayed 4 weeks where the delay was unlikely to significantly impact patient prognosis. Examples included stage lung cancer, lymphoma, or benign brain conditions. "Priority III" cases could be delayed for 30 days or more where the delay was unlikely to impact patient prognosis. Examples included early stage breast or prostate cancer. Prioritization was decided by the attending radiation oncologist and presented at daily contouring rounds. Additional changes included preferentially choosing hypofractionated treatment regimens if clinically reasonable, spacing out treatments to reduce crowding in waiting rooms and in hallways, disinfecting all common surfaces between patients, conversion of all meetings to video conference, and increasing communication with staff to transparently share updated information when available. The medical physics and dosimetry group adapted these general guidelines for our specific clinical contributions. Strategies are shared in subsequent sections.

2.A. | Staff management and remote work
Our first task was to identify what physics and dosimetry activities could be performed remotely to most effectively enact social distancing. Essential clinical physics responsibilities were split roughly into three categories: External beam treatment planning, special procedures, and hardware quality assurance (QA). Patient-specific QA is always performed after hours or on the weekend and thus was relatively unaffected as QA staff were not placed at significant additional risk. Similarly, monthly QA was planned such that contact with other patients and staff members was minimized.
Non-urgent machine service was consolidated to limit vendor visits to the clinic.
Under normal circumstances, there is an on-call physicist at each radiation medicine site in the health system. At our largest clinical site, there is a morning on-call physicist and an evening on-call physicist. For the COVID preparedness plan, we eliminated all on-site oncall physicist duties except the morning and evening on-call physicists at our main clinical site. These physicists would act as on-call for the entire health system and, if local troubleshooting was required, the on-call physicist would contact nearby physicists who could travel to the clinic, perform the necessary maintenance, and return home. Similarly, dosimetrists provided on-site coverage with one dosimetrist at our main clinical site during treatment hours.
All physicists and dosimetrists who were not needed for on-site coverage or procedures were asked to work remotely. Physicists and dosimetrists who were present on-site were provided protective equipment including surgical masks, gloves, and ample disinfectant for routine wipe downs of workstations and equipment. 2.C. | Analysis of efficiency and quality during the pandemic It was extremely important to maintain high-quality standards for our patients. Previously, we have reported the development and use of our checklist-based "No Fly" system. 13,14 It was emphasized to all staff that the "No Fly" system should be followed and safety should not be compromised due to the added complexity of the pandemic.

2.B. | Communication
The efficacy of our preparedness plan was analyzed in several ways. First, we calculated the number of work hours (defined between 8:00 AM and 6:00 PM) elapsed between handoffs in the external beam treatment planning process. Second, we assessed the timeliness of first day chart checks, weekly chart checks, and final chart checks. Third, we reviewed the radiation oncology incident learning system (ROILS) entries to assess the impact on safety. Each   with the remainder working remotely. Based on the remaining scheduled procedures and assigned on-call, we estimate that six to seven physicists were on-site during treatment hours on any given day with the remainder working from home. One dosimetrist contracted COVID-19 and was quarantined for 3 weeks. One dosimetrist had symptoms consistent with COVID-19 and was quarantined for 1 week. Six physicists were quarantined for 2-3 weeks each due to symptoms consistent with COVID-19, prolonged exposure to someone with confirmed COVID-19, or travel to an area where an outbreak occurred. From what we can ascertain, however, it appears that quarantine efforts were fruitful in that the virus did not spread among team members. If team members were symptomatic, they were not assigned work until they recovered. If team members were quarantined but asymptomatic, they were asked to perform clinical duties remotely.
A total of 263 patients were planned during this time period.
Two-hundred and seven were planned on the "standard" timeline The number of physics-related events in our local ROILS database decreased by 68% in 2020 when compared to the same time frame last year. Part of this decease, however, can be attributed to a 50% drop in the total number of reported incidents, most likely due to a natural deprioritization of reporting during the COVID-19 event.
F I G . 1. Planning efficiency during COVID-19 altered work arrangement. "Urgent" timeline includes cord compressions, palliative treatments, etc. "Standard" timeline includes three-dimensional-conformal and intensity-modulated plans. Data were collected over comparable six-week time period in 2019 and 2020.
The web-based survey was completed by 31 of 42 physics/ dosimetry group members. Although 76% of respondents reported having all the tools they needed to perform their work remotely, 39% said that configuring remote access was somewhat to very difficult and 63% reported connection problems at least once per week, with 20% reporting connection problems multiple times per day. Despite this, 83% stated their transition to remote work was "neutral," "somewhat easy," or "very easy." Large majorities reported motivation and focus equivalent to or better than that experienced in the office (87% and 83%, respectively), with 71% estimating they were just as or more efficient working remotely compared to the office. This is despite more than half of respondents (54%) reporting additional responsibilities beyond work, for example, caring for children (38%) or caring for sick family members (10%). Nearly half still found email as the best way to communicate (48%) with text messaging close behind (26%). Participants were also asked, given their experience during the COVID-19 crisis, how they would prefer to work in the future. The results were mixed: 13% preferred entirely in-office, 13% preferred entirely remote, 29% preferred mostly office with 1-2 days remote, 22% preferred mostly remote with 1-2 days in-office, and 22% preferred an even split between office and remote work.

| DISCUSSION
The impact of COVID-19 on clinical operations in a radiation oncology department cannot be overstated. In the past 2 months, numerous publications have provided recommendations for radiation oncology clinics to remain operational during the most significant public health crisis in a generation. Zaorsky et al. recommend the "RADS" framework, which stands for "Remote visits, Avoid radiation, Defer radiation, Shorten radiation." 15 Several site-specific recommendations have been published to aid physicians in decisions of avoiding or deferring radiation and toward specific fractionation regimens to shorten radiation. [16][17][18][19] Many of these works, however, were accepted for publication and made available online after the coronavirus began to spread exponentially in the greater New York area.
The purpose of the current work was to evaluate a pandemic preparedness plan in a therapeutic medical physics and dosimetry ser- It is possible the authors focused on maintaining standard staff levels while increasing disinfection frequency and personal protective equipment. At our institution, we took advantage of the remote infrastructure already in use for our geographically spread department to maximize social distancing and minimize the need for vigorous disinfection in physics and dosimetry office spaces in the department. One significant deviation between our infection control protocols and those in China: We did not monitor asymptomatic patient or staff temperature on a regular basis, rather relying on observable symptoms and contact history to determine risk of infection. Given the prevalence of asymptomatic COVID-19 positive patients, 22 we will consider integrating this check into our standard protocols.
One of the problems with the current scenario is that many of us have little experience in delivering care during a natural disaster. The results of the current study show that external beam planning operations were not substantially impacted by the pandemic preparedness plan (Fig. 1). Most steps of the treatment planning process were completed as quickly as or more quickly than a comparable 6-week time period in 2019. The time between CT simulation and dry run, however, was slightly longer, most likely due to the prioritization of patients and forced delays in treatment start date (Fig. 2). First day, weekly, and final chart checks were also completed in 2020 as quickly as or more quickly than 2019. There are, however, two major caveats in these findings. First, due to prioritization and subsequent reductions in non-urgent care, the total planning load was reduced by 25% in 2020 compared with the same 6-week interval in 2019. The number of chart checks was similarly reduced by 22-37%. Second, special procedures, with the exception of a few urgent cases, were eliminated. These two factors mean that dosimetrists had fewer plans to generate and physicists, who are primarily responsible for procedure coverage, were more available for planning and chart checking, both of which most likely lead to faster turnaround times. One drawback to our study was that we did not measure response time for on-site machine troubleshooting. With the exception of our main clinical site, physicists were called in from home to work on machines. Response times necessarily increased to include the physicist's commute.
Overall, the transition from normal operations to limited, remote operations was smooth and clinical efficiency was relatively unaffected. We attribute the majority of this success to technological infrastructure, centralized treatment directives, 24 and workplace culture established in our distributed, multisite environment over the past decade. In many ways, physics and dosimetry were already operating remotely: Dosimetrists at one site were planning for another site, physicists were checking plans from all over the system, team members were meeting via video conference, and physicists were rotating between sites on a regular basis to provide coverage for procedures and quality assurance. The electronic whiteboard was critical in keeping the treatment planning workflow organized, up-todate, and accessible to anyone on the departmental network. Based on the promising results of the current analysis, we summarize our recommendations for pandemic preparedness planning in Table 1.
We believe these recommendations are in-line with those published by other sources and could be generalized to other natural disasters with sensible customization to the situation and local needs.
It is tempting to view the current work situation as an opportunity to "test-drive" remote medical physics work and extrapolate to non-emergent (i.e., non-pandemic) conditions. Remote work by physics and dosimetry, even if utilized part time as described in our survey, could be advantageous. Physicists and dosimetrists could experience reduced commuting time, increased schedule flexibility, and a more focused environment with fewer interruptions. Employers could hire employees across the nation without requiring a physical presence on-site. Administrators would need fewer physical offices and workspaces for physicists and dosimetrists, an advantage not limited to radiation oncology. 25 Although the caveats listed in the previous paragraph cast doubt on the scalability of these findings to full patient load, a diverse and demanding array of special procedures, and longer term clinical projects such as acceptance or commissioning of new equipment, which are most likely on-hold at the current time, our survey certainly indicates there is interest in working remotely. We will investigate the feasibility of integrating remote work into standard clinical practice while maintaining a robust physical presence.

| CONCLUSION
The COVID-19 crisis has profoundly impacted the United States healthcare system. Radiation oncology is particularly exposed to disruption due to the vulnerable nature of our patient population and the logistics involved with recurring therapy on shared equipment. This manuscript described the actions taken by our medical physics and dosimetry group to ensure high-quality radiation therapy could be delivered safely and effectively to our patients in the midst of a York City and State is slowly decreasing. We are, however, preparing for a resurgence of the disease. Given our experience the past 6 weeks, we will refine and formalize our pandemic preparedness plan and will be ready to activate the plan should the need arise.

CONF LICT OF I NTEREST
The authors do not have any conflict of interest to disclose.