Urgent or Emergent?

Over the past year, COVID-19 has forced many optometrists to reevaluate what we consider a must-see emergency and what can wait to be seen. For the purpose of this article, we’ll consider urgent as a patient who should be seen within 24 to 48 hours and emergent as a patient who should be seen immediately in the office or referred to the nearest emergency eye care facility. Both categories have long, nonexhaustive lists, so I will limit discussion to the most common corneal and anterior segment situations.

WHAT’S URGENT?

Urgent patient complaints typically include flashes and floaters, acute red eye, blunt trauma without pain or loss of vision, acute swelling of eyelids without pain or discharge, and photophobia.

The most common conditions affecting the anterior segment are bacterial conjunctivitis and viral conjunctivitis (Figure 1), which can be hard to differentiate, especially via telehealth or photo. Bacterial conjunctivitis typically presents with a yellowy discharge and eyelid matting, whereas patients with viral conjunctivitis usually have more of a watery discharge. Although these conditions do not constitute an emergency, patients should be seen to address the infection or to manage the sequelae.¹

It should also be noted that viral conjunctivitis can present as a sequelae of COVID-19. Practitioners should consider sending patients for a COVID-19 test to rule it out, if they have not yet been tested.

A patient with a hordeolum (Figure 2) or lid swelling without a fever should be seen within 1 to 2 days to assess cause and start appropriate treatment. If the patient has a fever or there is concern for orbital cellulitis, he or she should be seen immediately.

WHAT’S EMERGENT?

Foreign Bodies

One of the most common ocular emergencies is an ocular foreign body (see main article photo, previous page), an event that may also involve corneal abrasion, conjunctival laceration, and even corneal perforation.

Again, patients with emergent situations should be seen immediately or referred to the nearest emergency eye care facility. Start with a thorough history to ascertain when and how the ocular trauma occurred and what the foreign body may be. If it involves vegetable matter, there can be concern for fungal infection.

Most foreign body incidents occur to individuals engaged in high-risk activities such as grinding, hammering, and welding while not wearing proper protective eye wear. During slit-lamp examination, locate and identify the foreign body, if it is still present, making sure to flip the lids. If the foreign body is embedded within the cornea or conjunctiva, determine how deep it is within the tissue. Fluorescein staining will help to identify any abrasions or lacerations and to check for a Seidel sign, which would indicate a perforation.

If the foreign body is not penetrating, it should be removed, and the patient should be put on a topical antibiotic. Metallic foreign bodies may leave a rust ring, which should be removed using an Alger brush.

Foreign bodies that have been present for more than 24 hours may draw white blood cells to the area or even trigger an anterior chamber reaction, requiring more aggressive dosage of antibiotics.

In instances in which there may be a penetrating foreign body, dilation should be performed to assess the crystalline lens and posterior chamber for risk of cornea or globe perforation. In the event of a penetrating wound or perforation, the patient should be pressure-patched and referred immediately to a specialist. If there are concurrent eyelid or periorbital lacerations, the patient should first be sent to urgent care or the emergency room for suturing and imaging if indicated.

Chemical Exposure

Another common emergency is ocular chemical exposure. When a patient calls the clinic with this type of injury, he or she should be instructed to immediately flush the eye at an eye wash station, if one is available, or with water for 15 minutes. The patient should also be told to bring in or take a photo of the offending agent so that it can be determined if it is an acid or base. Base (alkali) chemicals such as oven cleaners, fertilizers, and concrete have a pH of 7.1 or greater, whereas acid chemicals such as those in car batteries and bleach have a pH of 7.0 or less.

When a patient with an ocular chemical exposure arrives at the office, irrigate the eye with sterile saline until the pH is between 7 and 8.² Alkali burns are the most severe because they penetrate deeper in corneal tissue, causing tissue death.²

Depending on the extent of tissue damage or irritation, the patient can be treated with a topical antibiotic and/or steroid, along with a cycloplegic agent to help with pain. For those with severe burns, it may be necessary to use an amniotic membrane or refer to a specialist.

Corneal Ulcers

Corneal ulcers, especially those caused by contact lens abuse, are painful and will have the patient waiting on your doorstep. It is important to culture the cornea with an antibiotic-resistance panel, especially if the ulcer is large, not responding to treatment, located within the visual axis, or if there is concern for fungal involvement or Acanthamoeba.³ In the case of suspected Acanthamoeba, it is also prudent to obtain confocal microscopy, if possible, to identify the cysts and treat early.

Herpes

Herpes simplex virus (HSV) type 1 and herpes zoster (HZ) can manifest throughout the eye, and both can be sight-threatening. HSV epithelial keratitis is a major infectious cause of corneal blindness.^4,5 Dendritic keratitis (56.3%) and pseudodendrites (76.2%) are the most commonly seen ocular recurrences of HSV and HZ, respectively.^6,7 HZ keratitis (Figure 3) can occur up to 1 month after the onset of dermatitis, and it responds best to oral antivirals. Neurotrophic ulcers can be recurrent and can cause problems long after the resolution of the initial occurrence.⁸

Topical antivirals such as ganciclovir ophthalmic gel 0.15% (Zirgan, Bausch + Lomb) and trifluridine ophthalmic solution 1% (Viroptic, Pfizer) are the treatments of choice for HSV epithelial keratitis. These agents may be coupled with oral antivirals, although use of oral antivirals for HSV is considered off-label.⁹ Two studies of the effectiveness of oral acyclovir found that it performed as well as topical acyclovir in patients with HSV epithelial keratitis.^10,11

Patients with multiple recurrences of HZ or ocular manifestations of HSV may benefit from long-term use of oral antivirals to prevent further flare-ups, as seen in the HEDS study and as suggested by the ZEDS study.^12-14

GET EVERYONE ON BOARD

It is important for practitioners to be mindful of who is an emergent patient, but it is equally important for our staff members to be educated about these situations as well. Typically, they are the ones triaging patients over the phone, so at minimum they need to know how quickly a patient should be seen and when to refer a patient to the hospital.

With COVID-19 on our minds and the need to keep unneeded traffic to a minimum in our clinics, it requires balance to identify and treat our truly emergent patients while still keeping everyone safe.