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Oct 31, 2011

Hyphema:  blood in the anterior chamber of the eye. It may appear as a reddish tinge, or it may appear as a small pool of blood at the bottom of the iris or in the cornea.
Grade 1 - less than 1/3rd of anterior chamber
Grade 2 - 1/3 to 1/2 of anterior chamber
Grade 3 -greater than 1/2 but less than grade 4 (see below)
Grade 4 - Anterior chamber completely filled, also known as 8 ball hyphema
Causes:
Blunt trauma-most common cause, generally the vessels that join to iris to the eye
Spontaneous
Lymphoma
Leukemia
Child abuse
Post surgical
Does it matter how much blood accumulates?
Yes a large bleed is worse than a micro bleed but both are really sentinel events for the potentially worse re-bleed. It is the re-bleed that carries a higher risk of blindness.
How do you prevent the re-bleed?
Bed rest or light activity
To prevent a re-bleed into the anterior chamber which may cause obstruction of vision, or a rise in intraocular pressure. No reading - movement of the eye can precipitate loosening or loss of clot.
Elevation of the head of the bed
Approximately 30 - 45 degrees (so that the hyphema can settle out inferiorly and avoid obstruction of vision, as well as to facilitate resolution) laying flat will not cause any permanent deficit though will cause difficulty seeing or blurry vision.
Wearing of an eye shield
This prevents accidental rubbing of the eyes, which can precipitate a re-bleed.  DO NOT APPLY PRESSURE TO EYE. Use a metallic Fox Shield or paper cup
Avoidance of NSAIDS
 Aspirin or ibuprofen (which thin the blood and increase the risk of a re-bleed) - instead, acetaminophen can be used for pain control.
Sickle Cell Screen
If African American or Mediterranean check for sickle cell disease, patients are at increased risk even if just sickle cell trait. MUST KNOW THIS IS GOING TO GIVE DIAMOX AS IT CAN CAUSE SICKLING.
Medical Treatment
 Aminocaproic acid -  to reduce further bleeding (decreases the likelihood of a re-bleed)
Aminocaproic acid (also known as Amicar,) is a derivative and analogue of the amino acid lysine, which makes it an effective inhibitor for proteolytic enzymes like plasmin, the enzyme responsible for fibrinolysis. For this reason it is effective in treatment of certain bleeding disorders .
Cycloplegic eye drops - to dilate and rest the pupil
The best is atropine because it completely paralyzes the movement of the iris, where other cyclopleigic drops allow for some movement.
Check Intraocular Pressure 2 reasons
1.      Blood can clog the trabecular meshwork and cause the IOP to become dangerously high
2.      Elevated pressure can cause blood cells to be forced into the eye causing staining of the cornea
Elevated Intraocular Pressure Treatment
1.      Timolol – B-blocker that is a aqueous suppressant, quick acting and few side effects
2.      Topical carbonic anhydrase inhibitor -Inhibition of carbonic anhydrase in the ciliary processes of the eye decreases aqueous humor secretion and thus lowers the intraocular pressure in the anterior chamber
a.       Brinzolamide (trade name Azopt)
b.      Acetazolamide  (trade name Diamox) - can be given IV in extreme cases
c.       Dorzolamide (trade name Trusopt)
3.      Alpha 2 agonists- acts via decreasing synthesis of aqueous humor, and increasing the amount that drains from the eye through uveoscleral outflow
a.       Brimonidine (trade names Alphagan and Alphagan-P)
b.      Apraclonidine (trade name Iopidine)
4.      VERY RARELY- Paracentesis may be preformed

From the land down under, a must have for every ED: Link to The Emergency Eye Manual