Case: A 12-year-old male was hit in the right eye with a baseball just prior to arrival, now with headache, nausea, and vomiting, with swelling and pain around his right eye. Patient was unable to look upward, and had pain with looking downward. When he presented to the Emergency Department, his initial heart rate was 44 BPM. Patient received emergent CT head which showed small volume retrobulbar hematoma, concern for entrapment of the right lateral rectus muscle, and acute mildly displaced right orbital floor fracture. Ophthalmology and OMFS were emergently consulted and recommended transfer for pediatric oculoplastic evaluation for retrobulbar hematoma, right orbital floor fracture, and high concern for entrapment.
- A drop in heart rate by more than 20%, with associated nausea, syncope, or hypotension, after force is exerted on the extraocular muscles or globe of the eye, is known as the oculocardiac reflex. The bradycardia that develops is typically sinus bradycardia. In some cases, this reflex has been known to cause arrhythmias, asystole, and cardiac arrest. This reflex can occur with facial trauma and nerve blocks, however, it is most commonly found during ophthalmologic surgery.
- This reflex occurs with activation of the vagus nerve from nerve pathways originating from the stimulation of the opthalmic division of the trigeminal nerve. The vagus nerve activation results in a diminished chronotropy, creating the response.
- Removal of the cause, which in the setting of trauma, means consulting ophthalmology for an intervening procedure.
- In the interim, patients can be stabilized using management for bradycardia, such as atropine, placing the patient on the pacing pads, and careful cardiac monitoring.
- If signs and symptoms are concerning for oculocardiac reflex in the setting of trauma, emergent CT and ophthalmology consult is recommended. Evidence of ocular muscle entrapment, such as limited extra-ocular movements, diplopia, or proptosis, is an indication for emergent ophthalmology consult.
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4. Walker RA, Adhikari S. Eye Emergencies. In: Tintinalli JE, Ma O, Yealy DM, Meckler GD, Stapczynski J, Cline DM, Thomas SH. eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 9e. McGraw Hill; 2020. Accessed September 16, 2023. https://accessemergencymedicine-mhmedical-com.ezproxy.rowan.edu/content.aspx?bookid=2353§ionid=222404436