Advanced Trauma Life Support ATLS Student Course Manual 2018

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APPENDIX A n Ocular Trauma
to the optic nerve and globe. Signs of a retrobulbar
hemorrhage with compartment syndrome include
decreased vision, elevated eye pressure, asymmetrical
proptosis (eye bulge), resistance to retropulsion, and
tight eyelids against the globe (“rock-hard eye”).
A CT scan can reveal retrobulbar hemorrhage, but
only a clinical exam will determine whether this
bleeding is causing a compartment syndrome and
requires treatment. Vision loss can occur after about
1.5 hours of impaired blood supply, so immediate
treatment is imperative. If you are concerned about
a retrobulbar hemorrhage causing a compartment
syndrome, immediately contact a provider who has
the ability to perform canthotomy and cantholysis.
Canthotomy alone (i.e., cutting dermis only) does not
improve retrobulbar compartment syndrome. It is
the cantholysis that increases the size of the orbital
compartment, which is equivalent to a performing
a fasciotomy.
Do not delay treatment with canthotomy and
cantholysis by obtaining a CT scan for further proof
of hemorrhage.
Orbital fractures can also result in entrapment of
extraocular muscles within the bony fracture site.
Repair within 48 hours of onset is recommended to
avoid muscle ischemia and permanent damage; thus,
consult an ophthalmic specialist to evaluate for this
condition. Larger fractures with significant bony
displacement are less likely to cause muscle belly
impingement and ischemia. Larger fractures usually
occur in adults; entrapment and smaller fractures are
more common in children, whose bones are less brittle.
Chemical Burns
Chemical burns are true ocular emergencies and
must be treated as soon as the patient arrives. Initial
treatment involves copious irrigation of the affected
eye and requires little equipment. Ideally, a liter of
normal saline or lactated ringers (use tap water only
when sterile solutions are not available) is connected
to a Morgan lens. Place the lens in the eye, and tilt the
patient’s head so that the fluid runs out toward the
temple (not into the other eye). If a Morgan lens is not
available, cut a length of IV tubing bluntly to maximize
flow. When possible, the patient can hold the tip of the
tubing on the nasal aspect of the eye so the water runs
out of the eye. When both eyes require irrigation, you
can connect a nasal cannula to fluid and place it over
the bridge of the nose so it drains into both eyes. Be
sure to call the ophthalmic specialist at this time to
notify him or her of the situation.
While flushing the patient’s eye, obtain details about
the chemical. For example, is it acid or base, and is
it a liquid, powder, or other solid material? Alkaline
solutions are usually more damaging to the eye and
often require more flushing to normalize the pH (~ 7.0).
Powders have small granules that can easily get stuck
in the superior and inferior fornices of the eye. This
situation sometimes requires inverting the eyelids and
directly flushing with saline through a 10-cc syringe
to dislodge the granules.
After each liter of solution, or about every 30 minutes,
stop the fluid, wait 5 to 10 minutes, and check the pH
of the tears. While you are waiting, it is ideal to start
the eye exam. When the pH is neutral (~ 7.0) you may
stop irrigating the eye. If the pH is not neutral, continue
this cycle of irrigation, flushes to the fornix, and pH
checking until the tears are neutral. This process may
require hours of time and liters of saline, so patience
and perseverance are crucial. If you are in doubt about
whether all chemical has been cleared from the eye,
continue to flush until the ophthalmologist arrives to
examine the patient. Based on the ophthalmic exam,
treatment will likely include antibiotic ointments, oral
pain medications, and possible drops for inflammation
and elevated eye pressure.
Open Globes
Open globes include eye injuries that have full-thickness
penetration through the sclera or cornea. The size and
extent of penetrating injuries varies considerably.
Some injuries are so small that a microscope is
required for diagnosis; others involve visible foreign
bodies still lodged in the eye. Signs of an open globe
include a peaked pupil, shallow anterior chamber,
corneal or scleral laceration, abnormal pigmented
tissue pushing through the sclera or cornea, and the
presence of many floating red or white blood cells
(seen on slit lamp examination) in the aqueous
humor fluid.
A Seidel test can locate small leaks of aqueous fluid
from the anterior chamber. To perform a Seidel test,
anesthetize the eye, wet the fluorescein strip, and
wipe the strip over the area of concern while keeping
the patient from blinking. The undiluted fluorescein
appears dark orange in normal light; but if a leak is
present, it becomes light orange or green when viewed
under blue light.
Although many ocular trauma scores have been
developed to determine the degree and prognosis of
globe injury, initial treatment of all open globes is the
same. Once the condition is identified, immediately
consult an ophthalmic specialist and describe the
situation. Prepare the patient for surgery or transfer,
because open globes are surgical emergencies that
require immediate intervention in hemodynamically
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