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Pediatric Dentistry 538 WEB Lecture
Child Management – Sedation and General Anesthesia
Author – Dr. Norman Tinanoff
SPECIFIC OBJECTIVES:
The student should know:
1. The general concepts and requirements of sedation for children.
2. The anatomic and physiologic differences between children and
adults that affect sedation techniques.
3. The general concepts of the techniques and agents that are used to
sedate child patients for dental procedures.
4. The indications for general anesthesia to perform oral rehabilitation in
children.
METHODOLOGY:
ASSIGNMENT:
WEB Lecture
McDonald and Avery, 2000; Chapters 14, pages 297-324; Chapter 15,
pages 325-348 - 534
Synopsis
Concepts of Sedation in Children
The goals of conscious sedation for pediatric patients are to control behavior that
interferes with the provision of dental care and to produce a patient that will have a positive
attitude toward future care. Sedated children have all reflexes intact, have the ability to maintain
a patent airway and can respond to physical stimuli and verbal commands. Deep sedation
involves partial or complete loss of the ability to continuously maintain a patent airway and the
patient does not respond purposefully to physical stimulation or verbal commands.
Requirements for sedation:

Thorough knowledge of agents to be used.

Careful planning taking into consideration patient’s age, weight and behavior.

Patient evaluation to consider conditions that might alter the expected response
including previous experiences with sedation, lung and airway patency.

Medical history that includes current medications, allergies, previous hospitalizations.

Well-documented informed consent that includes risks, benefits and alternative
procedures.

Office facilities that allow for appropriate monitoring.

Emergency medical services and office personal thoroughly trained in their use.
Anatomic and Physiologic Differences in Children Compared to an Adult
Basal metabolic activity is greater in children, which affects drug response and
oxygen demand. Airway management is more difficult in children because of narrow
nasal passages and frequent hypertrophic tonsils and adenoids. Children have less
functional oxygen reserve due to smaller lungs with less expansion capability. The heart
rate is faster and the blood pressure is lower than adults. The effect and duration of
drugs is more variable in children.
Sedation Techniques
Sedative drugs may be administered by inhalation, oral, rectal, submucosal,
intramuscularly or intravenous routes. Inhalation of nitrous oxide-oxygen mixture is often
combined with any of the other routes. Nitrous oxide produces nonspecific central
nervous system depression with limited analgesia. At levels of 30-50%, it will produce a
somnolent patient who may appear dissociated and easily susceptible to suggestion. In
combination with other drugs, nitrous oxide potentiates the effects; however, it is safer
than increasing the sedative drug because it can be rapidly reversed.
The oral route is the most variable because the effect depends on absorption
through the gastrointestinal mucosa. It is also difficult to reverse oral medications.
Recovery time may be prolonged. Papoose Board is often used to restrain children who
are combative. Shoulder rolls keep the head slightly up and back. Nitrous oxide is
generally used with oral sedation.
Intramuscular sedation also has a similar problem as the oral route in that there
is a prolonged time to peak effect and the lack of reversibility. Intravenous sedation is the
easiest and most efficient, but extremely hard to manage in child patients because of
behavior and very small veins.
Common Agents
Antihistamines such at hydroxyzine (Atarax, Vistaril), promethazine
(Phenergan) and diphenhydramine (Benadryl) are rapidly absorbed from the GI tract and
ideal for oral administration. They produce drowiness, prevent histamine release and
have antiemetic properties.. Clinical effect is in 30 minutes. Excretion is by the liver and
the half-life is 3 hours. Vistaril dosage is 0.6 mg/kg and comes in a dosage of 25 mg/5
ml.
Antianxiety agents such as diazepam (Valium) medazolam (Versed) are rapidly
absorbed in the GI tract. They tranquilize as well as produce amnesia. Diazepam halflife is 20-50 hours and can have a rebound effect with the consumption of a fatty meal.
Oral dosage of 0.2 – 0.5 mg/kg. Medazolam has twice the potency as diazepam. Halflife is 2-5 hours. It can produce respiratory depression at high dosages. Dosage is 0.25
– 0.5 mg/kg, supplied as syrup in a concentration of 2 mg/ml. Flumazenil is a
benzodiazepine receptor antagonist and reversal of sedation can be given with an initial
dose of 0.2 mg, with repeats at 1-minute intervals.
Sedative hypnotics such as barbiturates can produce all levels of CNS
depression. Short-acting barbiturates include seconal, triazolam and pentobarbital. They
are not used that often because of other more modern drugs. Chloral hydrate (Noctec),
25-60 mg/kg, taken orally has an onset of action within 30 minutes, peak effect in 1 hour,
and half-life of 8-11 hours. It has an unpleasant taste and irritates the gastric mucosa.
Young children should not receive more than 1-gram total dose. At higher dosages and
in combination with other drugs there can be loss of a patent airway.
Dissociative agent such as Ketamine (Ketalar) produce a cataleptic state with
profound analgesia and amnesia. Dosage 3 – 7 mg/kg IM. Disadvantages increase
salivation, increase heart rate, potential for delirium in older children, potential for
laryngospasm. Advantage is rapid onset, no respiratory depression, lack of skeletal
movement. Often used with medazolam (to potentiate effect and amnesia) and atropine
(to reduce salivary secretions).
Narcotics such as meperidine (Demerol) and fentanyl (Sublimaze) produce
hypnotic states, relief from pain and respiratory depression. They are powerful
potentiators of other CNS depressant drugs. Demerol can be administered orally but with
rapid loss due to liver metabolism. Dosage in all three routes is 1- 2.2 mg/kg. Oral syrup
is 50mg/5ml; parenteral solutions come in 25, 50, 75 and 100 mg/ml. Fentanyl is
approximately 1,000 times more potent that meperidine. Dosage is 0.002 – 0.004 mg/kg.
Nalozone (Narcan) is the preferred narcotic antagonist. It acts in 2-5 minutes after a
subcutaneous dose. Duration of reversal is about 45 minutes. Dosage 0.1 mg/kg with
subsequent dosages of 0.1 mg/kg every 2-3 minutes. Caution -- the duration of the
opiate is longer that that of the antagonists.
Monitoring
If the patient is being sedated, heart, respiratory rate, blood pressure and oxygen
saturation need to be continuously monitored. Hypoxia is the primary complication in
children. Pulse oximeters are adequate for measuring blood oxygen saturation, but
devices that measure the respiratory concentration of carbon dioxide (capnographs) is a
better measure inspired and end-tital respirations.
Dental Procedures Performed on a Sedated Child Patient
Note monitoring devices on the child
General Anesthesia
There are many indications for treating a child in the hospital with general anesthesia for
oral rehabilitation. Some of these include:
 very young children requiring extensive dental work.
 children that have to travel significant distances for dental care.
 children with mental or physical handicapping conditions that makes
treatment in the outpatient setting very difficult.
 children with severe dental phobias that does not permit dental care in the out
patient setting.
Dentists who wish to work in the hospital OR generally must have advanced training that
has included experience in the hospital setting. Additionally, dentists must apply for and receive
hospital privileges from the hospital credentials committee.
Dental procedures are performed as a “dirty case” which means that absolute sterile
operating conditions are not followed. However, the patient is draped with sterile clothes, and the
operators perform normal scrubbing and gowning procedures.
Instruments for restorative procedures in the OR are the same as those for procedures in
the dental operatory. The use of rubber dam isolation is preferred for all operative procedures.
The treatment plan may be modified in that all restorations should provide greatest longevity.
Conservative procedures are not performed on questionable teeth.