Oculocardiac Reflex During Facial Surgery
Hsin-Shun Tseng1, Duen hern Shiau
Oculocardiac reflex (OCR) is not very well known among plastic surgeons, and it¡¦s an uncommon complication
in facial surgery. It can result in severe morbidity and mortality if OCR occurs. It is a vagally mediated bradyarrhythmia
after orbital manipulation. OCR is usually followed by stretching the muscles on the eyelids ¡V it¡¦s associated with
tension on the extraocular muscles. In 1908, Aschner first described the trigeminal afferent pathway , And, in 1970,
Katz and Bigger described the pathway of reflex with more detail and clarity .
The reflex stimulates the trigeminal nerve at the sensory nucleus, and brain stem processing, resulting in stimulation
of the dorsal efferent nucleus of vagus nerve. We present a patient who showed bradycardia when elevating a
fractured zygoma buttress. The history and mechanism of OCR is also reviewed. (Changhua J Med 2005;10:
Key words: oculocardiac reflex, trigeminal nerve, bradycardia
Periorbital surgery is a routine operation in the
plastic field under local anesthesia. If vital sign monitors
like EKG¡¦s etc are not available, so profound bradycardia
during ocular manipulation may be easily overlooked.
The fact that some individuals demonstrate profound
bradycardia with tension on several different
muscles during the course of the surgical procedure had
been proposed by Aschner in 1908 . But it was only
until 1970 that Katz and Bigger described the pathway
of reflex more clearly . In 1988, Arnold RW et al
have observed profound bradycardia during similar surgery
on identical twins . We herein present a patient
who showed bradycardia during facial surgery.
A healthy 25-year-old man survived a vehicle accident
and got a right zygomatic fracture with an asymmetric
outward appearance. He accepted Gillies¡¦ procedure
and the subciliary approach to reducing bone fracture
under general anesthesia. While we were elevating
the zygoma with a Dingman elevator, the young man¡¦s
pulse rate suddenly fell to 30 beats per minute and the
operation was stopped. The anesthesiologist administered
0.2 mg of Glycopyrrolate intravenously immedi
ately. We tried to proceed with the operation but the
pulse rate fell drastically when elevating the zygoma.
Finally the operation was aborted.
A wide variety of causes have been associated with
profound bradycardia via vagotonic maneuvers including
the diving response, the Valsalva maneuver, the carotid
sinus massage and the oculocardiac reflex. The
common efferent pathway for these maneuvers originates
in the dorsal efferent nucleus of the vagus nerve,
resulting in an increase in cardiac parasympathetic impulses.
The Oculocardiac Reflex (OCR) mechanism has
been shown to be trigemino-vagal, and the pathway was
described by Katz and Bigger in 1970 . The reflex
was elicited by proprioceptive and pain receptors whose
neurons terminate in the rostral mesencephalic trigeminal
nucleus . The efferent pathway from the eyeball
winds through the long and short ciliary nerves to ciliary
ganglion, the Gasserian gangion and then runs to
trigeminal nucleus in the floor of the fourth ventricle.
Some short internuncial fibers in the reticular formation
connect the trigeminal nucleus to the motor nucleus of
the vagus nerve . The depression impulse from the
vagus nerve end in the heart and involved its rhythm
1Division of General Surgery, 2Division of Plastic and Reconstructive Surgery, Department of Surgery, Changhua
Christian Hospital, Changhua, Taiwan
Received: May 4, 2005 Revised: June 10, 2005 Accepted: September 23, 2005
Reprint requests and correspondence to: Dr. Hsin-Shun Tseng, Division of General Surgery, Department of Surgery,
Changhua Christian Hospital, 135 Nanhsiao Street, Changhua 500, Taiwan.
Changhua J Med 2005£»Vol 10£»No 3