Advanced Trauma Life Support ATLS Student Course Manual 2018

260
APPENDIX A n Ocular Trauma
of the conjunctiva and cornea, conduct the fluorescein
dye test:
1. Anesthetize the eye with topical drops.
2. Using a moistened fluorescein strip, place a few
drops of fluorescein in the eye. (The patient may
need to blink to fully distribute the dye.)
3. Shine a blue light (Wood’s lamp or
ophthalmoscope) on the eye.
4. The dye will fluoresce in the green spectrum
and highlight the area of epithelium that has
been disrupted.
Abrasions of the cornea or conjunctiva can be treated
with simple ophthalmic ointment. Lacerations of
the cornea or sclera are of greater concern because
when full thickness, they indicate an open globe.
This injury requires immediate consultation with an
ophthalmologist for further evaluation. Lastly, if you
note that the patient is wearing contact lenses; remove
them, as wearing contact lenses for an extended period
of time greatly increases the risk of infectious corneal
ulcers. The fluorescein dye test may also be helpful
in identifying infectious corneal ulcers and occult
open globes.
Iris: The iris is a spongy, distensible muscle that is
generally round and reactive to light. If the pupil is
round and reactive to light, but slightly larger than
the pupil of the unaffected eye, the patient likely has
a pupillary sphincter tear. This injury commonly
occurs with blunt trauma to the globe. However, if the
pupil is not round, further examination is warranted.
With smaller globe injuries, the globe may remain
formed, but the pupil will have an irregular “peaked”
appearance. Look for the iris plugging the hole in
the globe or poking out of the sclera or cornea in the
direction in which the peaked pupil is pointing: This
is where the full-thickness cornea or scleral laceration
should be.
Anterior chamber: The anterior chamber should
be relatively deep; i.e., the iris should be flat with an
approximately 45-degree angle between the iris plane
and the curve of the cornea, and be full of clear, aqueous
humor. When the iris is close to the cornea, or the
anterior chamber is “shallow,” aqueous humor may
be leaking out due to an open globe. Look closely for
clouding of this fluid, which may indicate the presence
of red blood cells. Blood in the anterior chamber,
known as a hyphema, has two forms: (1) dispersed,
with red blood cells floating in the aqueous humor
and thus making the patient’s vision and your view
into the eye hazy; (2) layered, with blood on top of
the iris; or layered, with blood inferiorly if gravity has
shifted the blood cells down. A hyphema may cause
dramatically elevated intraocular pressure and can
indicate significant trauma to the globe. It is important
to consult an ophthalmologist immediately if this
diagnosis is made.
Lens: The lens is typically clear in young people or
appears varying shades of yellow in patients older
than 40 years (e.g., indicating a cataract). The lens is
encased in a clear, taut capsule. If the capsule is violated,
the lens turns white, often swelling with time. This
injury can induce significant intraocular inflammation
and elevated intraocular pressure, unless there is a
concomitant large globe injury. If the examination
indicates a violated lens capsule, the globe is most
likely open, and the eye may contain a foreign body.
Posterior Exam
The posterior segment eye exam can be difficult,
especially if the pupil is small due to sedatives or pain
medications. You can usually observe the presence
of a red reflex (i.e., reddish orange reflection of light
from the retina) at a minimum. If the pupil is larger,
you can use an ophthalmoscope to visualize the optic
nerve and/or posterior retina, but this is still not a
complete exam. If you cannot view the back of the
eye, you cannot exclude the possibility of vitreous
hemorrhage, retinal detachment, or other pathology.
Unlike spontaneous retinal detachments, traumatic
retinal detachments or other posterior pathology is not
usually treated with emergent surgery. Nevertheless,
be sure to notify the ophthalmologist on call of your
findings because vitreous hemorrhage from trauma
is usually a result of significant force and the eye is at
risk for more serious injuries.
Specific oculAR injuries
Polytrauma patients are at high risk for many ocular
injuries. This section describes some of the most time
sensitive, vision-threatening injuries that trauma team
members may encounter.
Orbit Fractures and Retrobulbar
Hemorrhages
Fractures of the orbit may cause bleeding in the
muscle cone or around it. These compartments are
limited by the insertion of the eyelid tendons to the
bony attachments of the medial and lateral canthi.
If the bleeding is significant enough, a compartment
syndrome can develop that obstructs the blood supply
n BACK TO TABLE OF CONTENTS