An Approach to Lateral Canthotomy
A 73 year old male with a past medical history of hypertension, hyperlipidemia, CAD status post stent, presents after an assault. He was driving his car during a snowstorm and was tailgated by another car. The patient pulled his car over to the side of the road and got out of his car where he was ultimately assaulted by the driver behind him. He was hit in the head with a closed fist and knocked to the ground. Patient denies any loss of consciousness. Patient states he's on prasugrel, an antiplatelet agent. Patient is complaining of decreased vision and pain of his right eye. Patient is able to move his eyes with normal tracking and denies pain with extraocular movements.
Visual acuity in the right eye is sensitive to light. Intraocular pressure is 30-35 mmHg. No obvious globe rupture. Mild proptosis. Grade 1 hyphema.
Nondisplaced fracture of the right orbital floor
Comminuted nasal bone fracture
Right maxillary sinus hemorrhage
Hemorrhage of the supra lateral compartment of the right orbit.
No proptosis. Globe intact. No retrobulbar hematoma
Take Away #1 - Indications for Lateral Canthotomy
Increased intraocular pressures over 40
Afferent pupillary defect
Cherry red macula
Nerve head pallor
Take Away #2 - The Procedure
Consider procedural sedation if applicable and time allows
Anesthetize the lateral canthus with 1-2% lidocaine with epinephrine
Use a hemostat to clamp the lateral canthus for 30-90 seconds
Cut the lateral canthus 1-2 cm
Start by cutting the inferior crus
Remeasure the intraocular pressure. If still elevated cut the superior crus
If pressure is still elevated take a hemostat and intentionally create an inferior blow out fracture
Take Away #3 - Calibrating the Tonopen
To calibrate Reichert Tono Pen, invert device with ocular probe down
Press black button twice and see “CAL”, wait for calibration to say “-UP-”, Turn ocular probe toward ceiling. Wait for screen to read “GOOD”. If “BAD” is displayed restart calibration.
Vision may slowly improve within 15 minutes or over 6 hours
EMRAP HD has card to bring to bedside if performing lateral canthotomy.
Resus Crisis Manual has a how to do lateral canthotomy
Max MacBarb, MD is a current second year resident at Stony Brook Emergency Medicine.
EMRAP Retrobulbar Hematoma Jessica Mason MD, Stuart Swadron MD, Mel Herbert MD
Department of Emergency Medicine, University of Maryland School of Medicine, 6th Floor, Suite 200, 110 South Paca Street, Baltimore, MD 21201, USA. firstname.lastname@example.org
Resus Crisis Manual Scott Weingart MD, David Borshoff MBBS
Johnson D, Schweitzer K, Sharma S. Ophthaproblem: Can you identify this condition? Retrobulbar hemorrhage. Can Fam Physician. 2009 Jun;55(6):605, 607
Edited by Bassam Zahid, MD