Hospital Preparedness for COVID-19: The Known and The Known          Unknown

Daiki Kaito; Kazuki Matsumura; Ryo Yamamoto

doi:10.2302/kjm.2020-0011-OA

Abstract

In late March 2020, we faced a nosocomial outbreak of novel coronavirus disease 2019 (COVID-19) at Keio University Hospital, Tokyo, Japan. Presently, COVID-19 is an unprecedented worldwide biohazard, and a nosocomial outbreak can occur in any hospital at any time. Therefore, we reviewed the literature regarding hospital preparedness, the initial management of COVID-19, and the surveillance of healthcare workers (HCWs) to find information that would be generally useful for physicians when confronted with COVID-19. In terms of hospital preparedness, each hospital should develop an incident management system and establish a designated multidisciplinary medical team. To initiate case management, COVID-19 should be suspected based on patient symptoms and/or high-risk history and then should be confirmed by viral testing, such as reverse transcription polymerase chain reaction (RT-PCR) analysis. Although some patients will become critically ill, the guidelines for respiratory failure and septic shock for non-COVID-19 cases can be followed for supportive treatment. Antiviral medications should be carefully selected because the available information is confused by the large volume of preprint literature and unreliable data. HCWs who have come into contact with patients with COVID-19 can generate new in-hospital clusters of COVID-19 cases. Quarantine following contact tracking with risk stratification is effective in preventing transmission, and the essentials of medical surveillance include monitoring different types of symptoms, delegation of supervision, and continuation of surveillance regardless of the RT-PCR results. Preparation for COVID-19 is recommended before the first COVID-19 case is encountered.

Introduction

In late March 2020, we faced a nosocomial outbreak of novel coronavirus disease 2019 (COVID-19) at Keio University Hospital, Tokyo, Japan. After the epidemic in Wuhan, China,¹ sporadic COVID-19 infections were noted in Japan, and more than 700 patients were evacuated from the cruise ship Diamond Princess and admitted to hospitals in the Kanto area in February. Although some border controls were implemented, multiple clusters and community transmission were observed in early March in some regions, such as Tokyo and Osaka,² and Keio University Hospital’s nosocomial outbreak was recognized.

Considering that COVID-19 is currently an unprecedented worldwide biohazard, a nosocomial outbreak can occur in any hospital at any time; moreover, COVID-19 can be transmitted from asymptomatic persons.³ In this review, we describe hospital preparedness for a COVID-19 crisis, the initial management of suspected or confirmed COVID-19 cases, and the medical surveillance of healthcare workers (HCWs).

Preparing for the First COVID-19 Case

During the COVID-19 pandemic, demands for medical care may rapidly increase and can potentially overwhelm the capacity of hospitals. To prepare for incidental or expected encounters with the first COVID-19 case, crisis-compliant management is required, which includes reconstruction of the medical team and relocation of medical supplies, such as personal protective equipment (PPE) and ventilators.

Reconstruction of the team

Reconstruction of the organization should be initiated by assigning the designated personnel/group to the command and control role. The World Health Organization (WHO) Regional Office for Europe recommends creating a multidisciplinary incident management system (IMS) to tackle in-hospital COVID-19 crises and activating a hospital emergency response plan, if available.⁴ The IMS is composed of 10 key categories (Fig. 1) and aims to optimize “stuff, staff, and space” through specific actions (Table 1).⁵^,⁶

Fig. 1

Incident management system (IMS) with ten components structured for COVID-19.⁴A multidisciplinary IMS should be developed for tackling in-hospital COVID-19 crises.

Table 1. "Stuff, staff, and space" optimization for the COVID-19 crisis⁵^,⁶

	Demands	Difficulties	Potential solutions
Stuff	PPE (e.g., N95 masks, face shields, gowns, gloves) Devices (e.g., ventilators, monitors, CRRT, ECMO)	Lack of PPE and devices Overuse of PPE Hard to predict demand and supply	Communication with authorities Relocation of PPE and devices Rational use of PPE
Staff	Physicians (e.g., emergency, intensivists, respiratory, infection control) Nurses and support staff	Heavy workload, lack of manpower Risk of nosocomial infection, lack of knowledge on infection control and treatment	Shift working and psychological support Emergency response plan Education and training on IPC and treatment
Space	Beds in intensive care units and infectious disease wards Triage space	Lack of infection preventive systems (e.g., negative-pressure isolation)	Conversion of ORs to ICUs New triage location and alternative facilities (e.g., hotels, gyms)

PPE, personal protective equipment; CRRT, continuous renal replacement therapy; ECMO, extracorporeal membrane oxygenation; IPC, infection prevention and control; OR, operation room; ICU, intensive care unit.

Designated COVID-19 medical teams should be assembled from multiple specialties and should be stratified according to the disease severity (e.g., mild, moderate, and severe). Although treatment strategies and the relevant literature depend on the disease severity,⁷ they should be shared between the teams. To prevent confusion of HCWs on various management protocols, each stratified medical team should periodically conduct a narrative review of reported studies and discuss them with multidisciplinary professionals to develop a consensus.

Relocation of supplies

During the period of expected or existing supply shortages, prioritizing the use of key equipment will help their relocation. Based on the WHO and Centers for Disease Control and Prevention (CDC) guidelines, intensive care units, emergency departments, and infectious disease wards are typical places where unavoidable close contact and aerosol-generating procedures (AGPs) occur with patients with suspected or confirmed COVID-19; therefore, droplet and contact precautions (i.e., eye protection, isolation gowns, and facemasks) or airborne precautions (i.e., N95 respirators and powered air-purifying respirators) should be used with the highest priority.⁸^,⁹ Conversely, only standard precautions are usually needed in general clinics and general wards. In addition to avoiding excessive PPE use, reuse and/or extended use of PPE should be considered.

Suspecting and Diagnosing a COVID-19 Case

Patients with COVID-19 usually develop a wide variety of symptoms 4–5 days, and at most 14 days, after exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is the causative virus of COVID-19.¹⁰^,¹¹^,¹² Because the symptoms are not specific and are similar to those of other viral respiratory infections and because some diagnostic tests do not have sufficiently high sensitivity, diagnosis on the basis of fever alone or relying solely on viral testing is not recommended. Furthermore, in terms of hospital management, it is important to use uniform criteria for suspecting and diagnosing COVID-19.

How to suspect COVID-19

COVID-19 should be suspected based on signs and symptoms. A high-risk history, including contact with patients with COVID-19 or travel to epidemic areas, can be a trigger for suspicion in asymptomatic or presymptomatic patients. Symptoms of COVID-19 vary and include fever, cough, fatigue, loss of appetite, and shortness of breath, and some patients also show myalgia, sore throat, and headache.¹⁰^,¹³ Although alterations in the sense of smell or taste have been reported as the first apparent symptoms, mainly in patients with mild disease severity, most patients also complained of other symptoms, such as fatigue, cough, and fever.¹⁴ Furthermore, it should be noted that elderly and immunosuppressed patients may present with atypical symptoms, such as reduced awareness without fever,⁷ and that asymptomatic or presymptomatic patients with COVID-19 have been reported, although the prevalence is unknown.¹⁵

How to diagnose COVID-19

Generally, viral testing, such as reverse transcription polymerase chain reaction (RT-PCR) analysis, for SARS-CoV-2 can confirm the diagnosis of COVID-19, whereas other laboratory and imaging findings can support the diagnosis. Because medical resources are often limited in a COVID-19 pandemic, patients for RT-PCR testing should be deliberately selected according to severity and risk factors.¹⁶ Whether antigen detection tests can be used to confirm the diagnosis of COVID-19 remains controversial, and further studies regarding test performance and operational utility are needed.¹⁷^,¹⁸ Antibody testing is not currently recommended for diagnosis because positive results would suggest a preexisting infection, and testing should be carried out at least 21 days from symptom onset.¹⁹^,²⁰

Although an RT-PCR-positive result confirms the diagnosis of COVID-19, a single RT-PCR-negative result is insufficient to rule out COVID-19 because the sensitivity of RT-PCR is affected by the length of time from the exposure to SARS-CoV-2. Repeating RT-PCR testing at 24- to 48-h intervals is suggested for patients who are suspected to have COVID-19 based on the severity and timing of compatible clinical signs and symptoms.¹⁸ In a retrospective analysis of 51 patients with COVID-19, 12 (24%) had positive results on the second RT-PCR test after an initial RT-PCR-negative result, 2 (4%) had positive results on the third test, and 1 (2%) finally had an RT-PCR-positive result on the fourth test.²¹ To increase the test sensitivity, some groups have suggested that a lower respiratory tract sample, such as sputum, should be obtained for RT-PCR testing if an upper respiratory sample, including nasopharyngeal, mid-turbinate, and nasal swabs, produced a negative result.¹⁸ Saliva could be an alternative to nasopharyngeal swabs for RT-PCR, and its use has been anticipated as a less invasive screening tool.²²^,²³ Several preprint articles have reported that the sensitivity of a single RT-PCR test with saliva for diagnosing COVID-19 was in the range 50%–90%; consequently, further studies are warranted.²⁴^,²⁵

Abnormal laboratory results, such as lymphopenia or elevated D-dimer levels, are insufficient to exclude or confirm COVID-19.¹^,²⁶ Although typical chest X-ray findings, including interstitial changes and ground-glass opacities located in the bilateral lower lobes, have been reported in patients with COVID-19, a retrospective study revealed that chest X-rays showed no abnormalities in 58.3% of patients with COVID-19.²⁷ Similarly, computed tomography (CT) manifestations of COVID-19, including patchy or nodular ground-glass opacities, consolidation, reticular pattern, and crazy paving pattern, did not have adequate predictability for COVID-19; recent studies identified that the sensitivity of CT ranged from 54% to 98% and the specificity was only 25%.²¹^,²⁸^,²⁹^,³⁰

Initial Management of COVID-19

From the perspective of hospital management, designated teams stratified according to disease severity should be assembled to care for patients with COIVD-19; however, the basic initial strategy should be known by all physicians so that patients can be managed until the designated team takes over. Notably, as of July 30, 2020, remdesivir and dexamethasone have shown some clinical benefits for patients with COVID-19. Several concerns also should be emphasized in the early phase of management of COVID-19 patients; these include risks for aggravation, medications, and respiratory and/or hemodynamic support.³¹^,³²^,³³^,³⁴

Risk stratification

Although 80% of patients with COVID-19 experience only mild symptoms, and most of these recover naturally, patients with risks for deterioration are known to have the potential for rapid exacerbation and should be closely monitored.³⁵^,³⁶ A retrospective study of more than 70,000 patients with COVID-19 identified that approximately 5% of these patients had progression to severe disease.³⁵ Although there is limited information on risk factors for exacerbation of COVID-19, several comorbidities and older age are associated with disease progression; clinicians should take into consideration a patient’s age (older than 44 years), smoking history, obesity with body mass index ≥30, hypertension, diabetes, chronic cardiovascular disease, chronic lung disease, chronic kidney disease, cancer, and immunodeficiency.²⁶^,³⁷^,³⁸^,³⁹^,⁴⁰^,⁴¹^,⁴² The degree of abnormalities in laboratory findings, including lymphocyte count; D-dimer, troponin, aminotransferase, lactate dehydrogenase, and serum ferritin levels; and proinflammatory cytokines, such as C-reactive protein and IL-6, also reflect the severity of COVID-19.¹^,³⁹^,⁴²

Respiratory support

As reported in a retrospective study in China, 19% of patients with COVID-19 had hypoxic respiratory failure.³⁵ Notably, the median time from symptom onset to the deterioration to acute respiratory distress syndrome was 8 days, suggesting that patients will not be intubated immediately after symptom onset.⁴¹ Although respiratory support for patients with COVID-19 is basically the same as that for respiratory failure caused by other diseases, there are a few points to be aware of because of its highly infectious nature.

In adult patients with COVID-19, starting supplemental oxygen by nasal cannula is suggested when the peripheral oxygen saturation is <92%.⁴³ Although the discussion is ongoing, several guidelines recommend the use of a high-flow nasal cannula (HFNC) when acute hypoxemic respiratory failure has developed despite conventional oxygen therapy; a meta-analysis and systematic review showed that HFNC use reduced intubation among patients without COVID-19 and is referred to as a source of indirect evidence.³⁶^,⁴³^,⁴⁴ Although reduction of the number of patients who need intubation might be important in a setting with limited resources, the prevention of disease transmission to HCWs by avoiding the use of HFNC in patients with COVID-19 would be similarly valuable; the avoidance of HFNC use is suggested, without strong evidence, by some groups.⁴⁵ However, it should be also noted that exhalation during application of 15 L/min oxygen by open face mask would broadly spread the virus to a similar extent to HFNC at 60 L/min.⁴⁶ Furthermore, previous studies identified that HFNC use for patients with severe acute respiratory syndrome (SARS) did not increase the risk of transmission to HCWs, and patients wearing a surgical mask during HFNC therapy might be an effective measure for reducing droplet transmission.⁴⁷^,⁴⁸ Accordingly, excessive restriction of the use of HFNC seems unadvisable, and it should be provided in line with in-hospital policies.

Noninvasive ventilation (NIV) for patients with COVID-19 should be also cautiously discussed. Most organizations recommend HFNC rather than NIV because reduced 90-day mortality and decreased intubation rates were found among patients without COVID-19.⁷^,³⁶^,⁴³^,⁴⁹^,⁵⁰^,⁵¹ Regarding the transmission of pathogens to HCWs during NIV, no nosocomial infection was identified among 105 HCWs using appropriate PPE who treated patients with SARS.⁵² However, because a recent observational study reported that HCWs who developed COVID-19 were more involved in assisting with NIV than those who were not infected with COVID-19,⁵³ the indication of NIV should be carefully considered, following hospital policy.

Endotracheal intubation should not be delayed in patients with hypoxemic respiratory failure despite invasive oxygen treatment. To minimize exposure to aerosols and maximize the likelihood of successful intubation at the first attempt, intubation performed by the most experienced physicians is clearly recommended by several guidelines.³⁶^,⁴³ Assembly of the designated medical team in advance would be effective in preparing equipment before exacerbation of the patient’s respiratory condition.

Hemodynamic support

There are no peer-reviewed studies regarding the optimal strategy for patients with COVID-19 who require hemodynamic resuscitation; consequently, most guidelines, such as those by the American College of Emergency Physicians, the National Institutes of Health, and the Surviving Sepsis Campaign, refer to indirect evidence of critical illnesses, especially septic shock.³⁶^,⁴³^,⁵⁴

The Surviving Sepsis Campaign guidelines for COVID-19 recommend immediate resuscitation by crystalloids, followed by monitoring patients with dynamic parameters for hemodynamically unstable patients with COVID-19. Norepinephrine is also recommended as the first-line vasopressor for patients who cannot maintain mean arterial pressure despite adequate fluid resuscitation of 30 mL/kg.⁴³ These initial management procedures should be initiated before the designated team arrives.

Pharmacologic treatments

Although a wide variety of mass media and social media have claimed successful treatment of patients with COVID-19 using various medications, as of July 30, 2020, only remdesivir, a broad-spectrum antiviral drug, and dexamethasone, a potent anti-inflammatory corticosteroid, have been reported to be safe and effective in reducing the morbidity or mortality of patients with COVID-19.³¹^,³²^,³³^,³⁴ A peer-reviewed preliminary report of randomized clinical trials (RCTs) identified that COVID-19 patients treated with remdesivir had their time to recovery reduced by 4 days compared with placebo; however, mortality rates were not reduced and the final analysis of long-term outcomes needs to be followed.³³ Similarly, another peer-reviewed preliminary report of RCTs elucidated that patients with severe COVID-19 pneumonia who received dexamethasone 6 mg daily had significantly lower mortality compared with placebo.³⁴

Unfortunately, promising results for other agents from basic research, retrospective analyses, and studies on Middle East respiratory syndrome coronavirus and SARS have never been validated by RCTs, which are fundamental to establishing the optimal treatment strategy.⁴³^,⁵⁵^,⁵⁶^,⁵⁷^,⁵⁸^,⁵⁹ Physicians should be also aware that, in many articles, a considerable number of preliminary reports that have not been peer reviewed are referred to as valid results. It should be noted that some recently published articles in famous journals, such as The New England Journal of Medicine and The Lancet, were retracted because inconsistencies in the data were identified and reliability had been undermined.⁶⁰^,⁶¹ One such study reported that the authors had performed a large multinational registry analysis and had found unfavorable clinical outcomes following the use of hydroxychloroquine, all of which, unfortunately, are considered as fabricated by many researchers.⁶¹

The choice of antiviral medication should be carefully determined with thoughtful discussions between several specialties. Because of confused information globally, a quick narrative review of a considerable number of scientific reports is recommended to allow the correct interpretation of complex data, although the quality of the review should be maintained with multidisciplinary discussions.

Dealing with the Aftermath

Because patients with COVID-19 and HCWs who have had contact with patients with COVID-19 both could become new epicenters spreading SARS-CoV-2, physicians need to track all HCWs who have been exposed to such patients and should assess the degree of exposure.⁶² A retrospective review of cases during the initial surge of the COVID-19 outbreak in January 2020 found that a considerable number of HCWs were infected in Wuhan, China, which indicated that hospitals could generate new clusters of patients with COVID-19.¹ Based on these results and the fact that HCWs had more work-related contact with others than community-based working adults did,⁶³ multiple academic and/or study groups recommend physicians to monitor the onset of fever and respiratory symptoms among HCWs who have been exposed to patients with COVID-19.⁶⁴^,⁶⁵^,⁶⁶^,⁶⁷

Contact tracking

Considering that early identification of possibly infected HCWs is critical to prevent further spread of SARS-CoV-2, contact tracking immediately or at least within 24 h after the detection of a confirmed COVID-19 case is recommended.⁶²^,⁶⁶^,⁶⁷ All HCWs and patients who had contact with the confirmed case should be identified; then, risk stratification should be performed.⁶²^,⁶⁴^,⁶⁵^,⁶⁶^,⁶⁷^,⁶⁸ Although the definition of “contact” and the risk assessment approach varies from the simple method adopted by Public Health England to the complicated categorization of the CDC,⁶⁴^,⁶⁵^,⁶⁶^,⁶⁷ valuable information always includes the duration of contact, type of contact (e.g., visiting patients, staying in the same room, face-to-face contact, direct care of patients, conducting AGPs), and the PPE worn by the HCW at the time of contact (Table 2).⁶⁴^,⁶⁵^,⁶⁶^,⁶⁷^,⁶⁸^,⁶⁹

Table 2. High-risk contacts for COVID-19 cases⁶⁴^,⁶⁵^,⁶⁶^,⁶⁷

	WHO⁶⁴	CDC⁶⁵	PHE⁶⁶	ECDC⁶⁷
Distance and duration of contact	Face-to-face contact within 1 m and for >15 min	Being within 6 ft for ≥15 min or any duration for AGP	Face-to-face contact or being within 2 m and for >15 min	Face-to-face contact or being within 2 m and for >15 min
Type of contact	Direct care for patients with COVID-19 without proper PPE	Unprotected direct contact		Direct physical contact, unprotected direct contact
PPE	Direct care for patients with COVID-19 without proper PPE	No respirator/facemask, no eye protection, inappropriate PPE for AGP		HCWs or laboratory workers without recommended PPE
Management	Monitoring for 14 days from last contact	Work exclusion and surveillance for 14 days from last contact	Work exclusion and home quarantine for 14 days from last contact	Work exclusion and surveillance for 14 days from last contact

ECDC, European Centers for Disease Prevention and Control; PPE, personal protective equipment; AGP, aerosol-generating procedure.

Literature is sparse regarding the ability of risk stratification to predict or identify SARS-CoV-2 infections in HCWs after exposure to a confirmed case of COVID-19. Although a recent systematic review and meta-analysis regarding the usefulness of PPE for SARS-CoV-2 and other betacoronaviruses reported that the use of face masks, N95 respirators, and eye protection was independently associated with a reduced risk of infection,⁷⁰ it included only four studies on patients with COVID-19, and each PPE type was not independently analyzed in each of the included studies.⁵³^,⁷¹^,⁷²^,⁷³ A case series of 121 HCWs exposed to an undiagnosed patient with COVID-19, that is one of the included studies in the systematic review, found that exposure without appropriate PPE during AGP and prolonged contact of >2 h were associated with nosocomial SARS-CoV-2 infection among HCWs.⁵³ Another descriptive study on 5442 HCWs concluded that the use of an N95 respirator with face mask reduces the incidence of infection, compared with no mask or surgical mask, although they did not analyze the type of contact.⁷¹ Given that the appropriate use of surgical masks along with proper hand hygiene was shown to be a protective factor against SARS, some groups suggested that constant surgical-mask wearing would be adequate for HCWs to prevent nosocomial infection of COVID-19.⁷⁴^,⁷⁵^,⁷⁶ It should be also noted that several case series of HCWs who had contact with a patient with COVID-19 reported that no one was infected with the virus regardless of risk categorization.⁶⁹

Differences in the quality of hand hygiene and environmental cleanliness across the study population would limit the interpretation of results on the association between unprotected exposure and transmission of SARS-CoV-2 to HCWs. Investigations regarding risk factors for nosocomial infection of COVID-19 in HCWs should be conducted to further understand which activities accelerate transmission. It should also be emphasized that little is known about specific risk factors for the progression of COVID-19 to critical illness among infected HCWs.

Quarantine and monitoring of symptoms

Quarantine following contact tracking with risk stratification is effective in preventing possibly infected HCWs from generating new clusters of patients with COVID-19.⁶²^,⁶⁴^,⁶⁵^,⁶⁷ Although several organizations recommend home isolation or work exclusion as quarantine for HCWs who have medium- to high-risk exposure to a confirmed case of COVID-19, medical surveillance for at least 14 days from the last contact is always recommended.⁶⁴^,⁶⁵^,⁶⁶^,⁶⁷

The duration and criteria for work exclusion will vary depending on the institution because, as mentioned above, there is no generally accepted risk stratification for predicting nosocomial infection of COVID-19 in HCWs.⁶⁴^,⁶⁵^,⁶⁷ Although work exclusion of too many HCWs would result in the shutdown of medical services, it should be emphasized that even one infected HCW has the potential to cause a new devastating outbreak with the disruption to service.⁷⁷

Several essentials should be recognized in medical surveillance. First, because various symptoms are reportedly related to COVID-19, monitoring fever alone is inadequate for medical surveillance. A case series of 14 HCWs who were diagnosed with COVID-19 revealed that 71% of them were afebrile, thereby suggested the necessity of monitoring mild upper respiratory infection symptoms.⁶⁹^,⁷⁸ Second, surveillance with delegated supervision is another key to the detection of infected HCWs. A survey of 16 HCWs who had respiratory symptoms within 2 weeks of exposure to a patient with COVID-19 identified that only one HCW voluntarily reported the symptoms, and most HCWs did not seek medical evaluation.⁶² Third, medical surveillance should not be terminated after a negative PCR test for SARS-CoV-2 in HCWs, particularly when the test was provided to all potentially infected HCWs as a screening test. Because the sensitivity of the PCR test for SARS-CoV-2 is relatively low, PCR as screening tests will result in a considerable number of false-negative results.⁷⁹

Mental healthcare for HCWs

HCWs are under both physical and psychological pressure during an ongoing COVID-19 outbreak, particularly when they are under medical surveillance.⁸⁰ A survey of HCWs in China revealed that most were afraid of introducing the virus to their home and refused any psychological help despite exhibiting excitability, irritability, and unwillingness to rest.⁸¹ Presenteeism, the phenomenon that individuals attend work despite being ill, occurs among HCWs due to an obligation to work or anxiety about reporting their illness.⁸²

The stress experienced by HCWs could result in psychiatric diseases, such as posttraumatic stress disorder and depressive disorder; therefore, mental healthcare should be broadly provided.⁸⁰^,⁸³ Strategies to deal with psychological distress might include psychosocial services, e.g., counseling HCWs and family members, assessing the accuracy of disclosed information, and eliminating disgrace related to the consequences following unexpected exposure to a COVID-19 case.⁸³

Conclusions

We reviewed the COVID-19-related knowledge available on hospital preparedness, initial case management, and surveillance of HCWs. This overview should prove useful for general clinical physicians when confronted with COVID-19. We hope that enhanced preparedness for COVID-19 can be achieved based on the information presented.

Conflicts of Interest

The authors declare no conflicts of interest associated with this manuscript.

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