Advanced Trauma Life Support ATLS Student Course Manual 2018

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APPENDIX A n Ocular Trauma
In checking for optic nerve dysfunction, use the
“swinging flashlight test” to look for an afferent
pupillary defect. When there is concern for optic
nerve dysfunction related to trauma, consult an
ophthalmologist for a detailed examination.
Intraocular Pressure
Handheld tonometry devices, such as the Tono-pen,
are now available in many emergency rooms. These
gauges have improved the clinician’s ability to check
eye pressures in diverse patient situations.
When using handheld tonometry devices, open the
eyelid while being careful not to push on the globe,
because doing so can falsely elevate the eye pressure.
Make sure the fingers retracting the eyelids are resting
on the bony orbit, not the globe. Always obtain 2–3
measurements of each eye, at the highest percentage
of reliability on the Tono-pen (normal eye pressure is
between 8 and 21 mmHg). The “data” or “%” reading
on the pen indicates the likelihood that this reading is
accurate. It is important to note that readings can vary
with mechanical ventilation, Valsalva maneuvers, and
accidental pressure on the globe during eye opening.
When possible, anesthetize the eye with topical
anesthetic ophthalmic drops (i.e., proparacaine) if
the patient is not fully sedated. Otherwise, the patient
may blink excessively or squeeze the eyelids shut when
the tip of the instrument touches the eye.
Without a tonometer, you can roughly estimate eye
pressure by gently pressing with two index fingers
on each side of the eye with the eyelids closed. If
you are unsure what normal is, press your own eye
or the patient’s unaffected eye in the same manner
and compare. Most importantly, evaluate whether the
patient has a firmer eye on the injured side.
If an open globe is suspected, do not check the eye
pressure, because you might drive more intraocular
contents from the eye. In such cases, check visual
acuity and conduct a visual inspection only.
Anterior Exam
The anterior exam addresses several aspects of eye
anatomy: the periorbita, extraocular muscles, lids,
lashes, lacrimal sacs, conjunctiva, sclera, cornea, iris,
anterior chamber, and lens.
Periorbita: Note any ecchymosis and lacerations
around the eye. Evaluate the forward extent of the
globes. This can be done with eyelids open or closed,
by looking down the face while the patient is supine
and determining if one eye is farther forward than
the other. This can also be evaluated radiographically
by using the axial cut of a CT head scan through the
orbits, measuring from the lateral wall of the orbit
to the nose on each side, and then determining
how much of the globe protrudes beyond this
imaginary line.
On a normal exam, when you gently push on the
eye through the eyelid, you will feel the globe give
a little and move backward. When this does not
occur, there is resistance to retropulsion, indicating
the possibility of increased pressure behind the eye,
as with a retrobulbar hemorrhage. Another sign of
retrobulbar hemorrhage is when the globe pushes
against the eyelids, creating such pressure that the
eyelid is taut and cannot be pulled away from the globe.
Lastly, when evaluating wounds of the periorbita,
always inspect lacerations to ensure they are not full
thickness and eliminate the possibility of a consealed
foreign body. Even if the globe seems unaffected, any
foreign bodies penetrating the orbit require immediate
ophthalmic examination to determine if the globe
is open.
Extraocular muscles: For patients able to follow
instructions, ask them to follow your finger up, down,
and side to side. Restricted ocular movement may
be from high pressure inside the orbit, from orbital
fractures, or from muscle or nerve injury.
Lids, lashes, and lacrimal sac: Examine the eyelids
to look for lacerations, and note whether they are full
or partial thickness. The nasal portion of the upper
and lower eyelids contains the superior and inferior
puncta and canaliculi, which drain tears from the ocular
surface. Tears flow through the puncta, then through
the canaliculi into the lacrimal sac and then down the
nasolacrimal duct into the nose.
Full-thickness lid lacerations require surgical repair
by a surgeon familiar with eyelid and lacrimal drainage
anatomy. Although this procedure need not happen
immediately, repair within 72 hours of injury increases
the likelihood of success. If the nasolacrimal duct
system is involved, it is most ideal to repair before
onset of tissue edema, so consult a specialist as soon
as you identify the issue. Be especially aware of eyelid
lacerations that align with conjunctival or corneal
lacerations, because these are often associated with
occult open globes.
Conjunctiva, sclera, and cornea: Note any
subconjunctival hemorrhages and their extent; the
more extensive they are, the more likely the globe itself
has sustained substantial injuries. If the conjunctiva is
lacerated, pay close attention to the underlying sclera,
which may also be lacerated. Again, an injury like this
could indicate an occult open globe.
Also check for lacerations or abrasions of the
conjunctiva, sclera, and cornea, noting their relationship
to any eyelid lacerations. To check for subtle injuries
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