treatment
plan
When
Syncope Strikes
BY
WILLIAM TOWNSEND, OD
One
of the most disturbing situations we encounter as healthcare providers is syncope
or fainting. We recently saw a 22-year-old male who complained of pain and foreign
body sensation
that began after he was grinding metal. Slit lamp examination revealed a 0.5mm foreign
body in the midperipheral right cornea. We advised the patient that we needed to
remove the foreign body from his cornea. After we instilled a topical anesthetic,
the patient collapsed. We immediately checked his pulse, evaluated his breathing
and determined that his airway was open. After we placed the patient in a supine
position and elevated his lower extremities, we placed a cool, damp towel on his
forehead and continued to monitor his vital signs. He recovered and eventually underwent
the procedure.
Why Syncope Happens
Syncope is defined as "a transient loss of consciousness with
an inability to maintain postural tone that is followed by spontaneous recovery."
It results from decreased cerebral perfusion, often due to hypotension. Brain tissue
can't store energy, so reduced perfusion for greater than five seconds may cause
syncope.
Syncope falls into two major categories. Cardiac syncope can be
associated with cardiomyopathy, congestive heart failure, valvular insufficiency,
obstruction, arrhythmias or conduction defects. Non-cardiac causes include vasovagal
syncope, dehydration, autonomic dysfunction and psychiatric disease.
Vasovagal syncope is a biphasic reaction centered around the fight-or-flight
reaction. It occurs when individuals experience a perceived or actual danger or
threat, especially when it involves pain. During the initial phase lasting a few
minutes, heart rate, cardiac output, blood pressure and total systemic resistance
increase. During the second phase, a dramatic reversal occurs: Heart rate, blood
pressure and peripheral resistance decrease rapidly. The resulting reduction in
blood flow to the brain causes decreased perfusion, lightheadedness and eventually
unconsciousness. Symptoms include nausea, sweating, clammy skin, skin pallor, dizziness
and loss of extra-ocular muscle control. Patients may also lose the ability to gaze
laterally.
Situational syncope dominates in eye care. It may occur after
tonometry, contact lens application or procedures such as foreign body removal.
Situational syncope isn't life threatening, but it can cause morbidity. The tendency
to faint may arise from abnormal vagal tone and tends to be familial.
What to Do
Management of syncope begins with knowing the ABCs of life support.
First establish that the airway is open, then make certain that the patient is breathing
and finally, check for a pulse. Then check pupillary reflexes. Although it's extremely
rare, vasovagal reactions may result in cessation of breathing, severe hypotension
and death.
Because the real problem is lack of cerebral vascular flow, place
the patient in the Trendelenburg position with the torso higher than the head. Your
exam chair may tilt back far enough to place the patient in this position, or you
can position him on the floor in a supine position and elevate his feet higher than
his head. Ammonia spirits (smelling salts) help re-establish consciousness. Placing
a cool, moistened towel on the patient's forehead is also helpful. Rarely, a patient
may totally lose pulse and blood pressure during a vasovagal reaction. In these
extreme instances, 0.4mg of atropine administered subcutaneously can save the patient's
life.
When patients recover consciousness, arrange for a friend or family
member to drive them home. Record the episode as well as your treatment and include
in your charting any measures you address such as transportation and monitoring.
Syncope is an uncommon, but very real condition that you should be prepared to manage
in practice.
Dr. Townsend is in private
practice in Canyon, Texas, and is a consultant at the Amarillo VA Medical Center.
E-mail him at drbill1@cox.net.
Contact Lens Spectrum, Issue: December 2006