Graefe's Archive for Clinical and Experimental Ophthalmology

https://doi.org/10.1007/s00417-020-04682-z

MISCELLANEOUS

Sustainable practice of ophthalmology during COVID-19:

challenges and solutions
Louis W. Lim 1 & Leonard W. Yip 1 & Hui Wen Tay 2 & Xue Ling Ang 2 & Llewellyn K. Lee 1 & Chee Fang Chin 1 & Vernon Yong 1

Received: 23 March 2020 / Revised: 27 March 2020 / Accepted: 1 April 2020

# Springer-Verlag GmbH Germany, part of Springer Nature 2020

Abstract
Purpose The Coronavirus (COVID-19) outbreak is rapidly emerging as a global health threat. With no proven vaccination or
treatment, infection control measures are paramount. In this article, we aim to describe the impact of COVID-19 on our practice
and share our strategies and guidelines to maintain a sustainable ophthalmology practice.
Methods Tan Tock Seng Hospital (TTSH) Eye Centre is the only ophthalmology department supporting the National Centre for
Infectious Diseases (NCID), which is the national screening center and the main center for management of COVID-19 patients in
Singapore. Our guidelines during this outbreak are discussed.
Results Challenges in different care settings in our ophthalmology practice have been identified and analyzed with practical
solutions and guidelines implemented in anticipation of these challenges. First, to minimize cross-infection of COVID-19,
stringent infection control measures were set up. These include personal protective equipment (PPE) for healthcare workers
and routine cleaning of “high-touch” surfaces. Second, for outpatient care, a stringent dual screening and triaging process were
carried out to identify high-risk patients, with proper isolation for such patients. Administrative measures to lower patient
attendance and reschedule appointments were carried out. Third, inpatient and outpatient care were separated to minimize
interactions. Last but not least, logistics and manpower plans were drawn up in anticipation of resource demands and measures
to improve the mental well-being of staff were implemented.
Conclusion We hope our measures during this COVID-19 pandemic can help ophthalmologists globally and serve to guide and
maintain safe access in ophthalmology clinics when faced with similar disease outbreaks.

Keywords COVID-19 . SARS-CoV-2 . Clinic management . Singapore

Introduction reproduction number close to or higher than SARS-CoV [3,

4] and MERS-CoV [5], COVID-19 represents a potentially
SARS-CoV-2, which causes COVID-19, is the third novel higher pandemic risk than the SARS outbreak in 2003 [6].
coronavirus in 17 years [1], first reported in Wuhan, China, Initial cases of zoonotic transmission from bats [7] have since
on 31 December 2019 [2]. It has since spread globally, with evolved into human-to-human transmission through droplets,
the World Health Organization (WHO) declaring it a Public fomites [8], fecal material [9], and tears [10]. Detection of
Health Emergency of International Concern on 30 January SARS-CoV-2 in tears and conjunctival secretions of infected
2020 and a pandemic on 11 March 2020. With its basic patients with conjunctivitis [10], similar to findings during the
2003 SARS outbreak [11], suggests a unique risk to the oph-
thalmology department.
Louis W. Lim and Leonard W. Yip contributed equally to this work. Clinical progression of COVID-19 seems similar to that of
SARS, with majority of cases (80%) having mild to moderate
* Leonard W. Yip disease after an incubation period of 5–6 days (range, 1–
leonard_yip@ttsh.com.sg
14 days). Common symptoms include fever (87.9%), dry
cough (67.7%), and fatigue (38.1%) [12]. Of note, 0.8% of
1
National Healthcare Group Eye Institute, Tan Tock Seng Hospital, 11 patients presented with conjunctival congestion [12], present-
Jalan Tan Tock Seng, Singapore 308433, Singapore
ing new challenges to ophthalmologists. Interestingly, the first
2
Yong Loo Lin School of Medicine, National University of Singapore, medical professional to sound the alarm on a possible
21 Lower Kent Ridge Rd, Singapore, Singapore
 Graefes Arch Clin Exp Ophthalmol

outbreak was a late Chinese ophthalmologist from Wuhan, Outpatient care

Hubei, China [13].
Singapore reported our first imported case on 23 January During this COVID-19 outbreak, our department’s weekly
2020. We have since enforced strict border control through outpatient visits’ no-show rate has increased significantly
travel advisories and entry restrictions from high-risk coun- from 13 to 33%. Possible reasons include patients postponing
tries like China and South Korea raised our “Disease Outbreak follow-up visits to avoid hospitals, or departments postponing
Response System Condition” (DORSCON) level from yellow visits to keep outpatient attendance low to reduce risks of
to orange and implemented measures to minimize community cross-infection [24]. Uncertainty in the duration of the out-
spread through cancelation or deferment of large-scale events, break [25] makes choosing a new appointment date difficult.
daily health checks at workplaces, and restricting doctors from Hence, patients who miss appointments, especially glaucoma
travelling between different healthcare institutions [14]. patients, are predisposed to sight-threatening complications
As of 26 March 2020, there were 462,684 confirmed cases [26].
and 20,834 deaths globally, with 81,961 of the confirmed
cases and 3293 of the deaths occurring in China [15]. One Inpatient care
hundred and ninety-nine countries and territories have been
affected [15], with numbers continuing to climb. Singapore The TTSH ophthalmology department only accepts inpatient
has had a total of 683 COVID-19 cases, with 172 discharged referrals from NCID or TTSH general wards. Movement of
and 2 fatalities [16]. High incidence rates were also seen in inpatients and ophthalmologists to and from different wards
Italy (74,386 cases), USA (63,570 cases), Spain (47,610 and the eye center poses significant means of cross-infection
cases), Germany (36,508 cases), and Iran (27,017 cases) [15]. between different wards, as well as between outpatient and
Being the only ophthalmology department supporting the inpatient services.
National Centre for Infectious Diseases (NCID), the national
screening center and the main center for management of Surgery
COVID-19 patients in Singapore, we would like to discuss
the impact COVID-19 has had on our practice, detail our past In ophthalmology, surgical turnover and caseload are high,
experiences with infection control in ophthalmology, and ap- with a daily average of 40 to 50 ambulatory day surgeries at
ply these concepts to develop a sustainable practice of oph- the TTSH Eye Centre. Hence, surgical procedures serve as a
thalmology at Tan Tock Seng Hospital (TTSH) Eye Centre. means for cross-infection between surgical patients from dif-
We hope to serve as a model to guide future management in ferent wards, as well as between patients and healthcare
ophthalmology clinics when faced with the current and similar workers from different departments.
disease outbreaks.
Healthcare worker

Challenges affecting ophthalmic practice As SARS-CoV-2 can cause conjunctivitis [27, 28], precau-
tions should be taken against transmission through aerosol
Infection control contact with the conjunctiva. Moreover, patients may be in-
fectious even before symptom manifestation [29]. Hence,
TTSH Eye Centre is one of the busiest outpatient clinics in ophthalmologists are at increased risks for COVID-19 be-
TTSH. With a usual patient load of 600 patients per day, the cause of their proximity to a patient’s nose and mouth and
risk of COVID-19 transmission is imminent and catastrophic. potential exposure to tears which may contain the virus [30].
Furthermore, ophthalmology is a unique practice requiring As such, the American Academy of Ophthalmology has rec-
routine use of reusable equipment in close contact with pa- ommended protection for the mouth, nose, and eyes when
tients and with many high-risk high-touch surfaces [17], there- caring for patients potentially infected with COVID-19 [28].
by increasing the risk of disease transmission among ophthal-
mology patients. Examples include the Goldmann applanation
tonometer (GAT) heads, slit lamp, contact lenses, eye drops, Sustainable ophthalmic practice guidelines
chin-rests, and table surfaces of ophthalmic diagnostic and
laser devices such as the Humphrey visual field and optical With no effective antiviral treatment available [31] and an
coherence tomography. This, coupled with the fact that effective vaccine unlikely to be widely available for up to
Coronaviruses can survive up to 96 h in biological fluids 6 months [32], the COVID-19 outbreak continues to challenge
and in high relative humidity and low temperature [18], thus the healthcare ecosystem. Thus, healthcare infrastructure
makes contaminated surfaces key sources of iatrogenic trans- should be directed at enhancing detection of cases and mini-
mission of infections [19–22] between patients [11, 23]. mizing transmission risks at all frontiers.
Graefes Arch Clin Exp Ophthalmol

In addition, the added physical, mental, and social stressors 2. Close contact with a case of COVID-19;
to ophthalmologists from both patient and personal safety 3. Acute respiratory infection (ARI) (cough, fever, and
concerns should be addressed [33]. shortness of breath).

General infection control Those negative for all of the above are given a round triage
sticker, while those with no travel or contact risk factors but
Ophthalmic equipment can be contaminated with respiratory have acute respiratory symptoms are given a hexagonal triage
droplets, tears, and conjunctival secretions of infected patients sticker. Those who are positive for all three will be denied
[10]. Unattended to, ophthalmic equipment may serve as hot- entry and sent to the NCID screening center instead
beds for virus contamination as patients often come in close (Table 1). To prevent the reuse of stickers, the color of the
contact with them. stickers is changed daily. At the electronic registration counter
Routine cleaning significantly reduces environmental con- of the eye center, patients and accompanying persons are
tamination [34]. However appropriate cleaning agents should again screened to pick out suspected COVID-19 cases based
be used. A review of studies on antiseptics-disinfectants for on the criteria listed in Figs. 1 and 2, in particular noting
human coronaviruses (HCoVs) recommended the use of a patients with acute respiratory symptoms.
povidone-iodine or combination of chlorhexidine with ethanol Patients and accompanying persons negative for the
and cetrimide for infection control against HCoV [18]. Most COVID-19 suspect criteria are given a green triage sticker.
alcohol-based solutions, such as isopropanol or ethanol, also Otherwise, the attending doctor is informed about the suspect
significantly reduced viral titers [35] and are recommended. patient to assess the need for a same-day consultation. Any
Surprisingly, some commonly used antiseptics-disinfectants suspect accompanying persons will be denied entry into the
formulated with only quaternary ammonium compounds or clinic and informed to leave the hospital premises.
phenolic compounds, or a combination formulation of chlor- Suspect patients in need of a same-day consult are given a
hexidine with cetrimide, were found to be ineffective against surgical mask and an orange triage sticker for identification,
HCoV [36] and thus may be ineffective against COVID-19 as before being escorted to the isolation “pink” room. Thereafter,
well. the treatment room nurse will check the patient’s visual acuity
Hence, we recommend that healthcare workers wash their as well as reassure and advise the patient on the isolation
hands with combination chlorhexidine with ethanol and protocols. Guidelines on the clinic triage protocol (Figs. 1
cetrimide, or hand-rub with alcohol-based solutions, and rou- and 2) have been affixed within the eye center to ensure that
tinely clean “high-touch” surfaces after each patient. To en- all triage personnel and medical staff are familiar.
sure proper decontamination of ophthalmic devices and opti-
cal surfaces, we suggest reviewing product inserts of each General patients
device for the most appropriate cleaning method and ensure
that the recommended cleaning agent is effective in With a stringent and robust triaging and screening system in
disinfecting COVID-19. In addition, we recommend avoiding place, most routine eye consults would thus be with patients
the use of the air puff to measure intraocular pressure to pre- without respiratory symptoms and at low risk for COVID-19.
vent the generation of aerosols from infected conjunctival se- Current recommendations from the WHO and the Centers for
cretions that risk transmission to healthcare workers [37]. Disease Control and Prevention would be personal protective
equipment (PPE) according to standard precautions. In our
hospital, standard precautions for all staff include surgical
Outpatient care masks in all clinical areas, mitigating the risk of inadvertent
exposure of a health care worker to an unidentified COVID-
Proper triaging of patients is imperative in a busy clinic to 19 patient.
reduce the spread of possible disease and for contact tracing In addition, since subclinical patients are capable of trans-
purposes. TTSH employs a stringent dual screening and mitting the virus [29], to prevent and limit cross-infection,
triaging process to classify patients and all accompanying per- reducing outpatient attendance is important. To this end, se-
sons based on their COVID-19 status. nior ophthalmologists screen through clinical notes to deter-
Firstly, at all entry points of the hospital, their temperatures mine patients with stable conditions whose appointments can
are checked by thermal image cameras, while stationed staff be safely rescheduled, while the eye center administrative
screen them for the following: team contacts patients at least 1 week prior to their scheduled
appointments to update them on their new appointments.
1. Travel or close contact with recent travelers to affected These patients will also have their prescriptions refilled. This
countries (Mainland China, Republic of Korea, Japan, has resulted in a 30% reduction of the 13,000 monthly
Iran, Northern Italy); patients.
 Graefes Arch Clin Exp Ophthalmol

Table 1 Questionnaire for screening of outpatients

Travel or close
Acute respiratory
contact with recent
illness (ARI) (Cough, Close contact with a
travellers to affected
fever and shortness case of COVID-19
countries (mainland Action
of breath)
China, Republic of
Korea, Japan, Iran,
Northern Italy)

Allow entry and give

ROUND sticker

Allow entry, give

HEXAGONAL sticker
and issue surgical
mask

Deny entry

Patients who defaulted their follow-up were also not cleanliness and hygiene, may lead to non-compliance of in-
neglected. After each subspecialty clinic, senior ophthalmol- fection control measures. Hence, it is imperative that new
ogists screen through a defaulter name-list from their clinic understanding and updates on COVID-19 are communicated
and give an appropriate time frame for rescheduling their ap- down the entire organization.
pointments. The administrative team will then contact patients
and update them on their new appointments.
Inpatient care
High-risk patients
Separating inpatient and outpatient ophthalmology care is the
For high-risk patients fulfilling the above criteria, full PPE is cornerstone of our practice to curtail the risk of cross-infec-
worn at all times by all involved healthcare workers, with the tion. As far as possible, inpatients should be seen at the bed-
patient placed and examined in dedicated isolation “pink” side. If specific equipment or investigations only available
rooms. Single-use consumables such as eye drops are used outpatient are required, the inpatient is then seen at an outpa-
to reduce the risk of transmission to the next patient, with tient clinic that has been specifically allocated for inpatient
non-disposable equipment cleaned with appropriate disinfec- use, with minimal to no interaction with other outpatients.
tants as discussed above. These cases are vetted to ensure they are non-suspect cases
The importance and enforcement of PPE should also ex- and afebrile. In addition, to avoid the congregation of inpa-
tend to the hospital’s janitorial service. Studies have shown the tients from different wards, separate time slots have been al-
presence of SARS-CoV-2 in an infected patient’s biological lotted for each group—ophthalmology inpatients are seen at
products and waste [9, 11, 12]. Yet, past experience from 8 am, while inpatient interdisciplinary referrals to ophthalmol-
SARS suggested that cleaners in affected hospitals viewed ogy are only seen after 9:30 am (Fig. 3).
their risk of exposure to SARS as low, at only 0.50 times that To further minimize interaction between these different
of doctors [38]. This is concerning as these misconceptions groups of patients, inpatients are under constant supervision
from cleaners, who play an essential role in the hospital’s by clinic staff, with diagnostic investigations minimized. This
Graefes Arch Clin Exp Ophthalmol

Fig. 1 Registration workflow for outpatients

is in concordance with the practice in Hong Kong during the Surgery

SARS outbreak, where inpatients were seen by the bedside
with portable equipment, and transfer of inpatients to the out- Aerosol-generating procedures such as tracheal intubation and
patient department was contraindicated due to their high risk manual ventilation before intubation increase the risk of trans-
of cross-infection [23]. mission of acute respiratory infections to healthcare workers
 Graefes Arch Clin Exp Ophthalmol

Fig. 2 Registration workflow for accompanying persons

by 3 to 7 times [37]. With ventilatory support required during Should emergency surgery be necessitated for confirmed
surgery, yet posing a risk to healthcare workers, we have post- COVID-19 cases, the operating theater is regarded as at high-
poned non-emergency elective cases to reduce caseload and risk and universal precaution measures will be taken, with the
potential infection risks to both patients and healthcare use of goggles and N95 masks for all staff within the operating
workers alike and reinforced screening for cough and fever theater. Similar measures for ophthalmic surgeries were used
during our pre-operative assessment if surgery is necessary. in other institutions during outbreaks [23, 40].
This has reduced our ambulatory day surgeries by about 50%.
Where surgery is needed, proper PPE is worn when
intubating patients who are undergoing general anesthesia. If Healthcare workers
manipulation of the nasopharynx is involved, such as
dacryocystorhinostomy, donning of appropriate PPE with Preparedness plans
the N95 mask is required for all operating theater staff.
Protective eyewear was found to reduce transmission risk Using lessons learned from the 2003 SARS and 2009 H1N1
in SARS [39]. We recommend the use of visor masks or outbreak, Singapore has continuously expanded and upgraded
coverspecs over the use of goggles, as although both increase its capacity to better manage emerging infectious disease out-
the working distance from the operating microscope and af- breaks like COVID-19. Steps taken include infrastructural re-
fects visualization during surgery, the latter further impairs form through the construction of the National Centre for
vision due to condensation. Infectious Diseases (NCID) and National Public Health
Graefes Arch Clin Exp Ophthalmol

Fig. 3 Workflow for inpatients

Laboratory and equipping all public hospitals with isolation Logistics

facilities ready to accept COVID-19 patients, as opposed to
centralized treatment of all SARS patients at TTSH in 2003. Currently, there is a high worldwide demand for PPE with
At an organizational level, formal platforms for collaboration many countries running low on supplies for their healthcare
have been established, with protocols ready for implementa- workers [41]. At the national level, although the Singapore
tion and training provided to healthcare professionals [33] as it government has maintained a 6-month national stockpile of
has been shown to reduce transmission rates [39]. PPE and masks in preparation for crises since SARS in 2003
 Graefes Arch Clin Exp Ophthalmol

[42], with available stockpiles prioritized for healthcare insti- with video conferencing. Mealtimes can also be staggered and
tutions [43], clinic managers should take stock of their current distanced seating (2 m apart) implemented in common staff
supplies and devise sustainable usage strategies for staff until areas.
resupply. For example, in our clinic, each healthcare worker is With social distancing in place, dissemination of critical
allotted 2 surgical masks per day, which must be signed out information through traditional means such as department or
from a centralized location to facilitate usage tracking, mini- hospital meetings will be inefficient and be a potential source
mize wastage, and ensure proper use of resources. of disease spread. In a rapidly evolving or complex healthcare
crisis, in addition to e-mails, communication can be supple-
Manpower mented with widely used smartphone messaging applications
such as WhatsApp and Telegram. The benefit is that unlike
Additional hospital and clinic screening efforts, as detailed short message service (SMS), which only allows single person
above, may draw staff away from their normal duties. In ad- interactions, modern messaging apps allow large group chats.
dition, ophthalmologists may have to augment and support This facilitates fast large group dissemination of information,
departments such as the emergency department and inpatient consultation, coordination, and action. Many functional
units that are under tremendous strain from the influx of pa- social-level group chats may already exist and should be
tients. Unprecedented community cluster outbreaks may lead tapped on, for example administrative, resident, nursing, or
to sudden surges of patients and place further strain on the ophthalmic technician groups. A situational crisis group for
hospital. Thus, these contingency requirements, though previ- COVID-19 may comprise key stakeholders for decision-
ously unthinkable, may require planning and forethought. To making in a clinic or department and leaders from different
achieve this, our department has undertaken superfluous functional groups. Such chats also serve as a temporary re-
staffing to cater to the differing elasticities of manpower de- source of relevant information, where documents and proto-
mand during this crisis [44] by restricting all leave and con- cols can be attached. Larger organizations may even have
ference attendances. approved secure instant messaging applications like the
TigerConnect, and organizational policies may dictate that
Personnel protection and training only these be used.

In addition to providing PPE, refresher training on how to don Resilience and mental well-being
and remove PPE should be provided to all healthcare staff to
decrease infection risk [39]. Repeat N95 mask fitting should The 2003 SARS outbreak taught us the significant psychoso-
also be carried out if done more than 1 year ago as the lack of cial impact a highly infectious disease outbreak can have on
training is associated with greater transmission risks [39]. In hospital staff [47, 48]. Inexperience in dealing with such an
lieu of live PPE demonstrations, online training material and outbreak among young healthcare workers, coupled with in-
videos could be circulated to avoid mass gathering of staff. creased workload and risk perceptions, compounds the phys-
Education on the rationale and importance of PPE should also ical and psychological stresses that healthcare workers have to
be continually emphasized as the physical discomfort and deal with daily [38]. Hence, the psychological welfare of staff
time-consuming nature can lead to lapses in compliance dur- must not be neglected. Assistance in this regard could be
ing a long-drawn outbreak. sought from affiliated psychiatry or psychology departments
To enhance the protection of all healthcare staff, updating or colleagues. Staff could be taught self-help methods on cop-
influenza vaccination to the prevailing seasonal strain can be ing with stress and increasing resilience. Avenues for seeking
considered. Though the influenza vaccine confers no protec- help should be made known to all staff so that those experienc-
tion against COVID-19, it may help avoid false alarms of ing an acute stress reaction can seek help. A 3S (Staff Support
clusters of fevers due to circulating strains transmitting among Staff) framework could also be instituted where fellow staff
staff, avoiding unnecessary quarantine measures [45]. members help look out for signs in colleagues and are trained
to provide informal psychological support. These efforts
Personnel communication and social distancing should persevere beyond the resolution of COVID-19.
Due to the uncertainty and prolonged period of stress dur-
Methods to reduce workplace transmission of influenza may ing this COVID-19 outbreak, it is crucial to support healthcare
be adapted for COVID-19. Workplace social distancing mea- workers through planning well-being initiatives (both within
sures have been previously studied as a means to prevent and beyond the hospital) and understanding the practical is-
influenza transmission [46]. Practical measures to reduce sues faced by staff [49]. In this aspect, an anonymized TTSH-
non-clinical work contact without affecting manpower re- NCID workplace well-being survey was conducted to aid in
quirements include stopping large group gatherings beyond understanding the difficulties faced by staff while at work
10 people and replacing department meetings and teachings during the COVID-19 outbreak. Other similar avenues should
Graefes Arch Clin Exp Ophthalmol

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