|Year : 2022 | Volume
| Issue : 2 | Page : 86-92
Impact of COVID-19 on workload and workflow in echocardiography unit in a tertiary care university hospital: A monocentric observational study
Mikhael Kossaify1, Hazar Kanj2, Christina Tarabay1, Antoine Kossaify3
1 Department of Cardiology, School of Medicine and Medical Sciences, USEK University, Kaslik, Lebanon
2 Department of Cardiology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
3 Department of Cardiology, School of Medicine and Medical Sciences, USEK University, Kaslik; Division of Cardiology, University Hospital Notre Dame Des Secours, Byblos, Lebanon
|Date of Submission||16-Aug-2021|
|Date of Acceptance||07-Jun-2022|
|Date of Web Publication||23-Jul-2022|
Dr. Antoine Kossaify
Cardiology Division, University Hospital Notre Dame des Secours, Byblos
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: The COVID-19 pandemic is a new unexpected worldwide condition with a heavy burden on health-care institutions and health-care workers.
Objective: We sought to examine the impact of COVID-19 on workload and workflow in the echocardiography unit in a tertiary care university hospital.
Methods: We conducted a monocentric observational study, evaluating workload and workflow during the COVID-19 year relative to the previous year.
Results: The findings show a substantial reduction in workload (55.20%) along with significant changes in workflow in the echocardiography unit during the pandemic. Changes in workflow involved measures implemented for protection, changes in echo indications which became more selective, changes in echo pattern, reduction in human flow in echocardiography laboratory, delays in reporting and archiving, and changes in training and teaching.
Conclusion: COVID-19 pandemic had a substantial impact on the echocardiography unit, with a significant reduction in workload and considerable changes in workflow. In the future, it is essential to be better prepared as individuals, health-care workers, health-care institutions, and the general community, to deal better with any potential “invisible enemy.”
Keywords: COVID-19, echocardiography, impact, unit, workflow, workload
|How to cite this article:|
Kossaify M, Kanj H, Tarabay C, Kossaify A. Impact of COVID-19 on workload and workflow in echocardiography unit in a tertiary care university hospital: A monocentric observational study. Heart Views 2022;23:86-92
|How to cite this URL:|
Kossaify M, Kanj H, Tarabay C, Kossaify A. Impact of COVID-19 on workload and workflow in echocardiography unit in a tertiary care university hospital: A monocentric observational study. Heart Views [serial online] 2022 [cited 2022 Aug 18];23:86-92. Available from: https://www.heartviews.org/text.asp?2022/23/2/86/351875
| Introduction|| |
By the end of the year 2019, a novel coronavirus (named SARS-CoV2) was reported in Wuhan, China. This coronavirus was responsible for Coronavirus Disease-2019 (COVID-19) causing a pandemic worldwide, affecting nearly 220 countries and territories., COVID-19 had a tremendous impact worldwide, mainly on health-care workers and institutions. Particularly, COVID-19 had a significant impact on workload and workflow in almost all affected countries and all medical domains.,, In this document, we sought to examine the impact of COVID-19 on the workload and workflow in the echocardiography unit at University Hospital Notre Dame des Secours (UHNDS), Byblos, Lebanon.
| Methods|| |
This is an observational retrospective monocentric study, realized at UHNDS. Patients addressed to the cardiac echo laboratory between March 1, 2020, and February 28, 2021 (hereafter named “COVID-19 year”) were eligible for the study. Most polymerase chain reaction (PCR) tests for COVID-19 were performed in our institution; however, we considered PCR tests as valid and they were accepted in our institution if they were performed in a University hospital and at most within the past 48 h. Data collection for the evaluation of workload and workflow was performed on a day-by-day basis, from observation, medical records, picture archiving, and communication system (PACS), as well as from the echocardiography unit registry. Eventually, these data were compared to those from March 1, 2019, to February 29, 2020 (hereafter named “previous year”).
Inclusion criteria consisted of all consecutive adult patients (>15 years old) whether inpatients or outpatients, who registered an appointment for an echocardiogram, whether transthoracic echocardiography (TTE) or transesophageal echocardiography (TEE), and performed the examination in the facility within the study allocated time interval. All inpatients who were admitted to the facility during the study time interval had a PCR test at UHNDS in the emergency department (if no valid PCR was performed as an outpatient), and sometimes, a chest CT scan when judged necessary. Moreover, all outpatients who registered an appointment for cardiac echo were requested to present a valid PCR before the echo examination. Echocardiographers used appropriate use criteria (AUC) to further filter and be more selective in indications.
Exclusion criteria consisted of patients confirmed as having COVID-19 and for whom echo indication was questionable (class II), patients with suspicious COVID-19, for whom PCR test is not performed or is pending, and all patients, for whom echo indication was judged as inappropriate (class III). There were no echo examinations accepted without prior appointment and/or without valid PCR; however, patients with a clinical condition where a cardiac echogram was judged urgent and necessary for the management were accepted with or without valid PCR, while taking all available protection measures (droplets and airborne protection). Of note, all requests for stress echo were rejected during the COVID-19 year. Among the 2584 echo demands (inpatients + outpatients) presenting to the echo unit, 509 (19.69%) were rejected, and 2075 (80.31%) were eligible and accepted.
All echocardiograms were performed by experienced sonographers using commercially available echocardiographs (iE33, Philips Healthcare, ultrasound system, Andover, USA or Vivid E95 Ultra Edition, GE Healthcare, Chicago, USA). All images were recorded digitally with the capacity to be analyzed offline. All echography data were collected using PACS and used unaltered for analysis, reporting, and archiving.
Echocardiography was performed by trained sonographers implementing standardized protocol including advanced methods as needed (i.e., three-dimensional echo). All indications of echocardiograms were checked initially by the attending physician, and in all cases, it was the cardiologist in the echo laboratory (echocardiographer) who performs the final check regarding the appropriateness of indications whether for TTE or TEE echocardiography while taking consideration and implementing the above-cited inclusion and exclusion criteria.,,
Focused cardiac ultrasound (FoCUS) was implemented mostly in highly suspicious or COVID-19-positive patients, similarly, the point-of-care ultrasound (PoCUS) was used frequently to avoid the risk of COVID-19 transmission owing to the transfer and positioning of such patients in the different geographical spaces.,
Criteria and procedures
COVID-19 was considered present when the patient had a positive PCR. COVID-19 was considered absent when the patient had a valid negative PCR. Patients were considered in the post-COVID-19 phase if they tested with negative PCR at least 14 days after having been documented with COVID-19. Patients were considered suspicious of COVID-19 when they presented with symptoms evoking COVID-19 and for whom the initial PCR test was either negative, pending, or not yet realized, also patients who had recent close contact with a COVID-19 patient were considered suspicious independently of the initial PCR result. Suspicious patients were requested to have a second PCR test and sometimes another paraclinical test (i.e., chest computed tomography [CT] scan) within 24–48 h according to clinical settings. For inpatients suspicious of COVID-19, they were kept in a gray-zone until clearance of their condition. For outpatients suspicious of COVID-19, the echo examination was postponed until clearance of their condition.
Symptoms evoking COVID-19 consisted of flu-like symptoms and/or acute respiratory syndrome and/or other nonspecific symptoms. The acute respiratory syndrome was considered present when new-onset dyspnea, and/or rhinorrhea, and/or cough were documented. Nonspecific symptoms evoking acute COVID-19 consisted of fever of unknown origin, dysosmia or anosmia, dysgeusia, or ageusia, and general fatigue or asthenia existing at the time of presentation.
By the term “workload,” we addressed mostly the quantitative aspect of echocardiography, and by the term “workflow,” we addressed the working process essentially related to the qualitative aspect of the echocardiography unit, including policies and procedures. No consent form was required given that it was an anonymous observational study without any interventional diagnostic or therapeutic testing. The study design was submitted and approved by the institutional research board; also the study was carried out under the Declaration of Helsinki.
Analysis was performed using the Statistical Package for the Social Sciences software (SPSS-version 18.104.22.1686, New York, USA (IBM). Data were expressed as number and percentage, or as mean ± standard deviation as appropriate.
Considering the small sample size, we have used the Shapiro–Wilk test to assess the normality of the data; to test whether the significance of workload changes during the pandemic, we have used the Wilcoxon Signed-Ranks test. A P < 0.05 was considered statistically significant.
| Results|| |
At the time of final editing of this paper (August 4, 2021), COVID-19 has affected nearly 200,566,388 individuals in 220 countries and territories and resulted in 4,264,642 deaths worldwide., The first COVID-19 case was reported in Lebanon on February 24, 2020, and the first COVID-19 case was reported at UHNDS on March 4, 2020; at the time of final editing of this paper, COVID-19 has affected the 565896 individuals in Lebanon and caused 7921 deaths., There have been two major national lockdowns in Lebanon in response to the COVID-19 pandemic, the first from mid-March 2020 to the end of May 2020, and the second from mid-January 2021 to mid-February 2021.
The UHNDS is a private tertiary medical center with 280 beds. During the pandemic, there has been a significant structural change at UHNDS, to adapt to the new situation, with the creation of a COVID-19 intensive care unit along with a normal ward for more stable COVID-19 patients for whom hospitalization was required.
During the COVID-19 year, there have been 335 COVID-19 patients admitted to the COVID-19 ward, and 111 COVID-19 patients admitted to the COVID-19 intensive care unit, making the total COVID-19 patients admitted at UHNDS during the COVID-19 year of 446 patients. Patients with COVID-19 admitted to the emergency department and who left (either transferred to another facility, or because do not need hospitalization) were not counted among the 446 patients.
[Table 1] shows patients' demographics and characteristics, and [Table 2] shows the workload variability by numbers and percentages.
|Table 2: The change in workload in the echocardiography (transthoracic echocardiograms+transesophageal echocardiograms) unit during the COVID-19 year in Lebanon, and the results were compared to those (month-by-month) of the previous year|
Click here to view
According to the above-cited quantitative data, there was an overall 55.20% reduction in echo workload, while the institution occupancy (hospitalization rate) dropped by 22.44%. Among the 2075 echo examinations performed during the COVID-19 year, there were 1349 (65.01%) confirmed with negative COVID-19, 602 (29.01%) patients were in the post-COVID-19 phase and 124 (5.9%) patients were either positive or highly suspicious (at the time of echo examination performance). Of note, TEE echo volume was reduced by 56.81% during the COVID-19 year compared to the previous year, whereas FoCUS and/or PoCUS echo raised 73.21% during the COVID-19 year compared to the previous year.
The Shapiro–Wilk test showed that the workload of echo during the year before COVID-19 is normally distributed (P = 0.32), whereas the data of the year during the pandemic (COVID-19 year) were found to be significantly different from a normal distribution (P = 0.05). The Wilcoxon Signed-Ranks test showed that the workload in the echo laboratory was significantly lower during the pandemic (Md = 191, n = 12) compared to the previous year (Md = 378.5, n = 12), z = −3.06, P = 0.002, with large effect size, r = 0.62.
Similar to the workload changes, there was a statistically significant impact of COVID-19 on the echocardiography laboratory workflow. The echocardiography unit remained functional regularly during all COVID-19 years, whether for regular daily shifts or emergencies. Among the five echocardiographers, some showed intermittent presence or even total absence, while two full-timers ensured a complete and regular schedule, including emergencies. Of note, some of the echo laboratory staff contracted COVID-19 in a mild form; however, it was unknown whether the source of infection was hospital-related or from extra-hospital contacts. [Table 3] shows the different factors involved in workflow changes during the COVID-19 year.
|Table 3: Changes in policies and procedures (workflow) before and during COVID-19|
Click here to view
There was no major structural change in the echocardiography unit, two echocardiography machines were functional during the pandemic, and regular decontamination of the procedure room and equipment was undertaken after each procedure. Droplets protection was implemented for staff while examining regular patients, adding to it airborne protection when examining highly suspicious or confirmed COVID-19 patients [Table 4]. There was a reorganization in the staffing along with changes in planning and scheduling to adapt to the situation, and such policies and procedures were seen implemented in most COVID-19 centers worldwide.,
As a direct effect of the pandemic and the repetitive lockdowns, along with physicians' fears or worries related to COVID-19, there were no scientific meetings at the beginning of the pandemic, particularly the meetings related to echocardiography teaching. However, many scientific meetings took place later as remote teaching (online), which changed later to the hybrid form (meetings with social distancing and/or while using online transmission using either Microsoft Teams or Zoom).
There were occasional and minor delays in reporting and archiving the echo examinations, owing to staff re-distribution or absence; however, the access to echo results was always available via direct communication with the operator. The human circulation flow in the echo unit was reduced to the minimum necessary persons (along with social distancing when feasible); accordingly, the presence of trainees (nurses or cardiology interns and fellows) was limited, also the hands-on training process was very restricted given that it increases the exposure time to the staff.
Of note, performing PCR tests systematically for every patient was mandatory before admission. Besides, most patients with suspicious symptoms were required to perform a second PCR test (±chest CT scan) within 24–48 h. Of note, patients stayed in a grey control area until their PCR results were obtained (unless clinical status requires immediate intensive care): If positive, and according to the clinical condition and other paraclinical tests, the patient may be discharged (with protection advice given to the patient and the close persons, and with medical prescription when required) or admitted to normal COVID-19 ward or COVID-19 intensive care unit.
| Discussion|| |
In this discussion paragraph, we will not address the background issue of COVID-19, whether it is a conspiracy, a human fabricated virus, or a natural pandemic, given that it is beyond the scope of this paper. Similarly, cardiac echo findings in COVID-19 are not within the scope of this study, and therefore, mortality and morbidity including cardiac consequences of COVID-19 were not specifically searched and analyzed in this study. Therefore, this discussion will address the changes in workload and workflow in the echocardiography unit during the COVID-19 year as stated in the introduction section. To the best of our knowledge, this study is the first to report the impact of COVID-19 on the workload and workflow in our facility (UHNDS).
Regarding the workload, we estimate that many factors are involved in the reduction of the workload: The impact of COVID-19 on the public, on health-care workers (worries and fears), and the repetitive lockdowns are considered major causal factors of workload reduction. During the peaks of the pandemic, most patients for whom a regular cardiac echo was scheduled postponed their examination given the fear of contracting COVID-19 in a health-care institution. The process of postponing occurred either at the request of the attending physician or as a consequence of the patient's own decision. Moreover, patients with suspicious symptoms were requested to repeat their PCR test within 48 h before performing an echo examination, and sometimes to perform a lung CT scan. Many of those patients ended up canceling their echo exam.
In addition, there was a reduction in patient's hospital admission in general, owing to a reduction of working staff including physicians who restricted patients' admission to emergencies, especially during high peaks of the pandemic. The reduction of the working staff was consecutive either too repetitive and frequent self-isolation periods (after inadvertent contact with PCR positive patient) or to working place redistribution in the setting of staff re-organization during the pandemic. Moreover, many of the hospital staff contracted COVID-19 and had to be isolated and treated, thereby the workforce was reduced.
Most importantly, and intending to reduce COVID-19 transmission risk, there was a restriction of echo indications to the minimum necessary (AUC, class I), given that echo, indications were filtered by the operator in the echo laboratory and this factor contributes significantly to the echo volume reduction., We already had an observational report in our facility regarding appropriate use criteria in echocardiography; however, the appropriateness factor was further adapted and implemented during the COVID-19 pandemic, as previously mentioned in the methodology section.,
Regarding the workflow, there was a decision in our institution to “get things done” despite all the obstacles and risks related to the COVID-19 pandemic, mainly to maintain the basic and advanced care to all patients whether COVID-19 or non-COVID-19 patients while ensuring reasonable though not always optimal protection to the medical and paramedical staff.
Echo indications were reviewed according to AUC, also a filtering process for each patient was applied, including data from the clinical status (i.e., fever, cough, dyspnea, etc.), chest X-rays, and chest CT scan (when available).,, The echocardiographer had the responsibility to make the last check regarding the indication of the echo examination, and also to adjust the timing of the examination according to clinical settings. Regarding the outpatients' echo examinations, filtering and selection were made on a case-by-case decision by the echocardiographer (cardiologist) based on clinical presentation and data from paraclinical tests. During the national peaks of COVID-19 cases, most cases of nonurgent patients were postponed, independently of PCR results.
As previously mentioned, all patients admitted to UHNDS, whether as regular admission or via the emergency room were screened for COVID-19. In all cases, outpatients who report being in contact with a COVID-19 patient within the past 14 days were requested to postpone their examination when their clinical status allows, otherwise they were oriented to the emergency room for further exploration and for a case-by-case decision. Echo examinations for COVID-19 patients were only accepted on the spot (without previous appointment) when suspicion of cardiovascular involvement is significant and when echo is estimated urgent and the result was expected to have an impact on clinical outcome.
Regular and droplet protection for operators and staff was performed on a routine basis, along with airborne protection when dealing with highly suspicious or positive patients. Furthermore, all hospital staff was requested to have a regular PCR test to keep up with their job requirements. Of note, some paraclinical tests (cardiac CT scan or MRI, laboratory biological tests, BNP, CPK-MB, etc.) were used as alternatives to cardiac echo in highly suspicious or COVID-19 patients when such paraclinical tests can provide useful clinical image and/or diagnosis (i.e., pericardial effusion, acute coronary syndrome, left ventricular dysfunction, etc.).
The use of face masks was mandatory for all hospital staff and to echo patients while they were in close contact with operators. Use of other personal protective equipment and safety protection measures (social distancing, hand sanitizing, adequate room aeration, etc.) [Table 4] was also implemented to ensure reasonable protection for medical staff and patients. Droplet or airborne protection was implemented by echocardiographers according to the type of patients examined.
For patients (whether inpatients or outpatients) with high suspicion or evidence of COVID-19, the PoCUS/FoCUS examination was implemented to shorten scanning duration and limit staff exposure, also to avoid the risk of COVID-19 transmission owing to transfer and positioning of such patients in different geographical spaces., Specific echo parameters were explored in these patients according to clinical settings, namely pulmonary artery pressure, left and right ventricular function, and pericardium.
During a pandemic, it is essential to minimize the exposure of health-care professionals given that they represent the major asset in the frontline to fight against an invisible enemy. TEE exposes the medical staff more to aerosolized particles. Accordingly, echocardiographers were very restrictive regarding TEE echo during the pandemic, given the relatively higher procedural time and higher risk for COVID-19 transmission; however, if TEE was judged necessary, it was carefully planned with the caring team to minimize exposure and potential transmission of the COVID-19 to medical staff.
The fact that online teaching and hands-on training were reduced or temporarily halted during the pandemic is a managerial policy that complies with local current practice and procedures; we had many reports regarding organizational policy and practice in this regard., Such policy and procedures were necessary to reduce human circulation and overcrowding in the echo laboratory, and to reduce COVID-19 transmission while keeping basic standards for students' education and training.,
The COVID-19 pandemic is a new unexpected health-care condition with a heavy burden on all health-care institutions and health-care workers worldwide. For that reason, there was a kind of unpreparedness (regarding human power or equipment) in most health-care facilities, creating sometimes some confusion in the workflow for the timely diagnosis and management of COVID-19 patients. Accordingly, the COVID-19 patients admitted at UHNDS exclude those admitted to the emergency department, with symptoms evoking COVID-19, and who left shortly after admission without performing a PCR test. The proportion of these patients is estimated roughly to be around 5%–10% of the total COVID-19 patients.
Lebanon has been going through a severe economic crisis since October 2019, such economic and social crisis affected the health-care system and had an impact on different social classes of citizens who might not afford to have an echo examination in a mostly private health-care system, and therefore such a fact could be a confounder in the parameter “reduction of workload.” Similarly, the potential presence of confounders in demographics is not excluded, and multiple regression analysis was not performed given the observational design of the study, focusing only on workload and workflow during the COVID-19 year.
Clinical and future implications
Protecting medical and paramedical staff during a pandemic is a must to keep up with the crisis while ensuring optimal care of all patients, whether COVID-19 patients or regular patients. Besides regular protection steps (masks, physical distancing, avoiding crowding, indoor spaces ventilation, repetitive hand washing and sanitizing, etc.), following recommendations and proceeding with vaccinations is necessary to fight against such a pandemic.
COVID-19 was the latest pandemic, but probably will not be the last; in this view, it is essential to learn from the past and present, to get better prepared emotionally, scientifically, medically, and organizationally (financial issues, protective equipment, staffing, reorganization, etc.), in health-care institutions and in the general community to deal better with future pandemics.
| Conclusion|| |
This observational monocentric study showed significant changes in workload and workflow in the echocardiography unit as a consequence of the COVID-19 pandemic. Appropriate and flexible adjustments were needed to adapt to changes regarding workflow and workload. The workflow managerial (policies and procedures) changes were rapidly initiated to adapt to the workload reduction, also to adapt to COVID-19 potential risks of transmission, while ensuring nearly optimal but possibly not the perfect quality of care in the real world which is severely impacted by this pandemic. To continue providing high-quality care while minimizing risk to ourselves, our patients, and the public at large, it is necessary to select carefully whom to image, where, and how to image.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Idogawa M, Tange S, Nakase H, Tokino T. Interactive web-based graphs of coronavirus disease 2019 cases and deaths per population by country. Clin Infect Dis 2020;71:902-3.
Dong E, Du H, Gardner L. An interactive web-based dashboard to track COVID-19 in real time. Lancet Infect Dis 2020;20:533-4.
Kvolik Pavić A, Zubčić V, Kvolik S. Workload changes during the COVID-19 pandemic and effects on the flow of cancer patients in the Maxillofacial Surgery Department. Med Glas (Zenica) 2021;18:133-7.
Quek LH, Tan GW, Pua U. Managing endovascular workload during COVID-19 outbreak-the Singapore experience. Ann Vasc Surg 2020;66:3-5.
Capotosto L, Nguyen BL, Ciardi MR, Mastroianni C, Vitarelli A. Heart, COVID-19, and echocardiography. Echocardiography 2020;37:1454-64.
Douglas PS, Garcia MJ, Haines DE, Lai WW, Manning WJ, Patel AR, et al
. 2011 appropriate use criteria for echocardiography. J Am Soc Echocardiogr 2011;24:229-67.
Kirkpatrick JN, Mitchell C, Taub C, Kort S, Hung J, Swaminathan M. ASE statement on protection of patients and echocardiography service providers during the 2019 novel coronavirus outbreak: Endorsed by the American College of Cardiology. J Am Coll Cardiol 2020;75:3078-84.
Ioannidis JP. Appropriate vs. clinically useful diagnostic tests. JAMA Intern Med 2013;173:1607-9.
Hussain A, Via G, Melniker L, Goffi A, Tavazzi G, Neri L, et al
. Multi-organ point-of-care ultrasound for COVID-19 (PoCUS4COVID): International expert consensus. Crit Care 2020;24:702.
Zhang L, Wang B, Zhou J, Kirkpatrick J, Xie M, Johri AM. Bedside focused cardiac ultrasound in COVID-19 from the Wuhan epicenter: The role of cardiac point-of-care ultrasound, limited transthoracic echocardiography, and critical care echocardiography. J Am Soc Echocardiogr 2020;33:676-82.
Kapur R, Gerg N, Kapur KK, Kapoor P, Kapoor PM. Cardiac echocardiography in COVID-19 infection. J Card Crit Care 2020;4:56-60.
Dweck MR, Bularga A, Hahn RT, Bing R, Lee KK, Chapman AR, et al
. Global evaluation of echocardiography in patients with COVID-19. Eur Heart J Cardiovasc Imaging 2020;21:949-58.
Rameh V, Kossaify A. Appropriate use criteria in echocardiography: An observational institutional study with the perspective of a quality improvement project. Clin Med Insights Cardiol 2016;10:23-8.
Ward RP, Lee L, Ward TJ, Lang RM. Utilization and appropriateness of transthoracic echocardiography in response to the COVID-19 pandemic. J Am Soc Echocardiogr 2020;33:691-2.
Goerlich E, Minhas AS, Mukherjee M, Sheikh FH, Gilotra NA, Sharma G, et al
. Multimodality imaging for cardiac evaluation in patients with COVID-19. Curr Cardiol Rep 202;23:44.
Kossaify A. Quality assurance and improvement project in echocardiography laboratory: The pivotal importance of organizational and managerial processes. Heart Views 2021;22:35-44. [Full text]
Elkhoury Z, Kossaify A. The medical director in healthcare institution: From monitoring to management for a safer and enhanced quality of clinical care. J Qual Health Care Eco 2020;3:000180.
Popescu BA, Stefanidis A, Fox KF, Cosyns B, Delgado V, Di Salvo GD, et al
. Training, competence, and quality improvement in echocardiography: The European Association of Cardiovascular Imaging Recommendations: Update 2020. Eur Heart J Cardiovasc Imaging 2020;21:1305-19.
Drake DH, De Bonis M, Covella M, Agricola E, Zangrello A, Zimmerman KG, et al
. Echocardiography in pandemic: Front-line perspective, expanding role of ultrasound, and ethics of resource allocation. J Am Soc Echocardiogr 2020;33:683-9.
[Table 1], [Table 2], [Table 3], [Table 4]