• Syncope is referred as sudden, transient loss of
consciousness that usually occurs secondary to a
period of cerebral ischemia.
• Types of syncope
– Vasovagal syncope
– Cardiac syncope
PREDISPOSING FACTORS FOR
– Emotional stress
– Reciept of unwelcome news
– Pain especially sudden
– Sight of blood or surgical or
other dental instruments.
• NON PSYCHOGENIC
– Erect siting or standing
– Hunger from dieting &
– Poor physical condition
– Hot humid crowded
– Male gender
– Age group 16 to 35 years
• Prevention of vasodepressor syncope is directed at
eliminating those factors that predispose an
individual to faint.
• Adequate air conditioning eliminates the heat
• Patient hunger, a result of dieting or a missed meal
before the dental appointment, also should be
considered; all patients, but especially those who
are anxious, should be requested to eat a light
snack or meal before their dental appointment to
minimize the risk of developing hypoglycemia in
addition to a psychogenic response.
VASODEPRESSOR SYNCOPE CAN BE
• Feeling of warmth
• Loss of color
– Pale or ashen- gray skin
• Heavy perspiration
• Blood pressure at
• Pupillary dilation
• Cold hands & feet
• Visual disturbances
• Loss of consciousness
• With The Loss Of Consciousness Breathing May:
1. Become irregular, jerky, & gasping;
2. Become quiet, shallow, and scarcely perceptible;
3. Cease entirely- respiratory arrest or apnea.
• The pupils dilate, and the patient takes on deathlike
• Convulsive movements and muscular twitching of
the hands, legs or facial and their brains become
hypoxic, even for periods as short as 10 seconds.
• Bradycardia, which develops at the end of the
presyncopal phase continues.
• A heart rate of less than 50 beats per minute is
common during syncope.
• The blood pressure which falls precipitously to an
extremely low level also remains low during this
phase and often is difficult to obtain.
• The pulse becomes weak & thready.
• Loss of consciousness is also associated with a
generalized muscular relaxation that commonly
leads to partial or complete airway obstruction.
• Fecal incontinence may occur, particularly when
systolic blood pressure falls below 70mm of Hg.
• Once the patient in supine position, the duration of
syncope is extremely brief, ranging from several
seconds to several minutes.
• If the patient remains unconscious for more than 5
min after proper positioning and management are
achieved, or if the patient does not undergo a
complete clinical recovery in 15 to 20 mins causes
other than syncope should be considered
POST SYNCOPE( RECOVERY)
• With proper positioning recovery is rapid.
• In the postsyncopal phase the patient may
demonstrate pallor, nausea, weakness and
sweating, all of which last from a few minutes to
• Symptoms persist 24hours.
• During the immediate postsyncopal phase, the
patient may experience a short period of confusion
• Arterial blood pressure begins to rise at this time, it
may not return to the baseline level several hours
after the syncopal episode
• The heart rate, which is depressed, also returns
slowly toward the baseline level and the pulse
• In addition a point worth stressing is that once a
patient loses consciousness the tendency for that
patient to faint again may persist for many hours if
the patient assumes a sitting position or stands too
soon or quickly.
Stress, whether emotionally triggered or sensorially
Causes the body to release into the circulation
system increased amounts of the catecholamines
epinephrine and nonepinephrine.
Their release is part of the body adaptation to
stress, commonly called the “fight or flight”
This increase in catecholamines result in changes
in tissue blood perfusion designed to prepare the
individual for increased muscular activity.
Among many responses to catecholamine release are a
decrease in peripheral vascular resistance and an increase
in blood flow to many tissues particularly to peripheral
In situation in which the this anticipated muscular activity
occurs, the blood volume that was diverted to the muscles in
the preparation for this movement is returned to the heart by
pumping actions of the muscles.
In this case peripheral pooling of blood may occur ; the blood
remains at or above the baseline level, signs and symptoms
of vasodepressor syncope do not develop.
In situation in which the planned for muscular activity does
not occur, the diversion of large volume of blood into the
skeletal muscle causes a significant pooling of the blood in
these muscles with an associated decrease in the volume of
blood being returned to the heart.
This leads to relative decrease in circulating blood volume, a
drop in arterial blood pressure, and a decrease in cerebral
blood flow. Presyncopal signs & symptoms are related to
decreased cardiac output, diminished cerebral blood flow and
other physiologic alterations.
• As blood pools in peripheral vessels and arterial
blood pressure begins to fall, compensatory
mechanisms are activated that attempt to maintain
adequate cerebral blood flow.
• These mechanisms include baroreceptors, which
reflexely constrict peripheral blood vessels,
increasing the return of venous blood to the heart,
and the carotid and the aortic arch reflexes, which
increases the heart rate.
• These mechanisms work to increase the cardiac
output and the maintenance of a close to normal
blood pressure, all of which are seen during early
• If the situation goes unmanaged these
compensatory mechanisms fatigue, which is
manifested through development of reflex
• Slowing of the heart rate to less than 50 beats/min
is common & leads to a significant drop of cardiac
output which is precipitous fall in blood pressure to
levels below the critical for maintenance of
• In such cases, cerebral ischemia results and the
individual loses consciousness
• The critical level of cerebral blood flow for the maintenance
of consciousness is established to be about 30 ml of blood
per 100g of brain tissue per minute. The normal value of
cerebral blood flow is 50-55ml per 100g per minute.
• In a fight or flight situation in which muscular movement is
absent with the patient maintained in the upright position,
the heart’s ability to pump this critical volume of blood flow is
not reached, leading to syncope.
• Convulsive movements such as tonic, or clonic contractions
of the arms and legs or turning of the head, may occur with
onset of syncope.
• Cerebral ischemia lasting only 10 seconds can lead to
seizure activity in patients with no prior histories of seizure
• Recovery is usually hastened by placing the victim
in the supine position with their legs elevated
slightly, improving venous return to the heart and
increasing blood flow to the brain so that cerebral
blood flow once again exceeds the critical level
necessary for maintenance of consciousness.
• Signs & symptoms such as weakness, sweating, &
pallor may persist for hours.
• The body is fatigued and may require as long as 24
hrs to return to its normal functioning state after a
• STEP-1 P (POSITION)
– As soon as presyncopal signs and symptoms appear, the
procedure should be halted the legs slightly elevated.
– This position change usually halts the progression of
– Muscle movement also helps increase the return of blood
from the periphery.
– If patients can move their legs vigorously, they are less
likely to experience significant peripheral pooling of
blood, minimizing the severity of the reaction.
• STEP-2: A B C
– AIRWAY - BREATHING - CIRCULATION
– The fairly common practice of placing the victim’s head
between his or her legs when presyncopal signs and
symptoms develop should be discontinued.
– Bending over to such an extreme degree may actually
further impede the return of blood from legs through a
partial obstruction of the inferior vena cava, resulting in a
greater decrease in blood flow to the brain.
– Furthermore, if patients lose consciousness while placing
head between their legs, this position does not facilitate
proper airway management.
– O2 may be administered through use of a full- face mask,
or an ammonia ampule may be crushed under patient
nose for speed recovery.
• STEP: 3 D( DEFINITIVE CARE)
– Modifications in future dental treatment should be
considered to minimize the risk of recurrence
– The planned dental treatment may proceed only if both
the doctor and the patient feel it is appropriate.
– If either party remains doubtful, treatment should be
• The basic management required for all
unconscious patients: P A B C
Step 1 Assessment of consciousness
• The patient suffering vasodepressor syncoper demonstrates
a lack of response to sensory stimulation.(Shake & shout)
Step 2 Activation of the dental office emergency
• Office team members should perform their assigned duties.
STEP 3 P
• The placement of patient in supine position with
slightly elevation of legs which helps in increase
the return of blood from the periphery.
• Clinical manifestations during syncope are
result of inadequate cerebral blood flow.
• Failure to place the victim in the supine position
may result in death or permanent neurological
damage secondary to prolonged cerebral
• This damage occurs in as little as 2 to 3 mins if
victim maintains an upright position.
STEP 4: A-B-C ( BASIC SUPPORT, AS
The victim must be assessed immediatetly and a patent
airway ensured. The head tilt- chin life position successfully
establishes a patent airway.
An adequate airway is present when the patient’s chest
moves and exhaled air can be heard and felt.
To assess circulation, the carotid pulse must be palpated.
STEP 5: D (DEFINITIVE CARE)
Adminsitration of oxygen
• Oxygen may be adminstered to the syncopal or postsyncopal
patient at any time during the episode.
Monitoring of vital signs
• Blood pressure, heart rate, respiratory rate should be monitored.
• Loosening of binding clothes such as ties, collars and belt.
• Use of respiratory stimulant( aromatic ammonia)
• If bradycardia persist an anticholinergic such as atropine
administered either I.V OR I.M
• If the victim doesnot regain conciousness after the
previous steps have been performed or doesnot
recover completely in 15 to 20 minutes, a different
cause for the syncopal episode should be
considered and the emergency medical service
• After recovery patient must not undergo any dental
treatment the remainder for that day.
• Body requires up to 24 hours to return to its normal
• Prior to dismissal of the patient from the dental
office, the doctor should determine the primary
precipitating event and any other factor that
contributed to it.
• Arrangement must be made for a person with
vested intrest in the health and safety of the patient
to take the patient home