OXIDE -OXYGEN INHALATION
Dr.zameer pasha
Sedation
• The provision of adequate anxiety control is an integral part of the
practice of dentistry.
• It is of fundamental importance that the level of sedation must be
such that the patient remains conscious, and is able to both
understand and respond to verbal commands.
• Conscious sedation: • A minimally depressed level of consciousness,
that retains patient’s ability to maintain an airway independently and
respond appropriately to physical stimulation and verbal command
• Deep sedation: a controlled state of depressed consciousness,
accompanied by partial loss of protective reflex, including inability to
respond to verbal commands
• General anesthesia : control state of unconsciousness accompanied
by complete loss of protective reflexes including inability to maintain
air way independently and respond to verbal commands
• Goals for sedation to control behavior to allow procedure to be
completed successfully.
• • Kids under age 5 or 6 (chronologically or developmentally) may
require deep sedation
Pre- sedation assessment
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A fully recorded medical history.
Blood pressure.
Weight, if recorded.
ASA status.
A dental history.
A conscious sedation and general anaesthetic history.
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Dental treatment plan.
The selected conscious sedation technique.
Any individual patient requirements.
Provision of pre- and post-operative written instructions provided
before treatment.
• Written consent for conscious sedation and dental treatment.
TYPES / ROUTES OF ADMINISTRATION
• Inhalation
• Nitrous oxide
• Desflurane
• Sevofuraine
• Oral
• Diazepam
• Triazolam
• Intramuscular
• Ketamine
• Midazolam
• Intravenous
• Midazolam
• propofol
• Conscious Sedation for Children
• Nitrous oxide/oxygen is usually the technique of choice for conscious
sedation of pediatric dental patients
• Nitrous Oxide is a very quick acting inhaled sedation medicine that
decreases discomfort and anxiety.
• Sometimes called “laughing gas”
• Often given at the dentists office
• Nitrous Oxide is a sweet-smelling, colorless gas.
• It is heavier than air or oxygen
History of N2O
• 1793 - Joseph Priestly invented N2O
• In 1844, Dr. Gardner Colton
• Initially used as an anesthetic agent
in 1844. by Dr. Horace Wells
• Roberts in 1990 and dr. kevin allen
demonstrated relative analgesia on
child patient
Pharmacokinetic properties Onset
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Anywhere from a few seconds up to 3-5 minutes
Crosses the blood-brain barrier rapidly Elimination
Rapid elimination
Unchanged with exhalation from the lungs
Do not hold a child close to your face while they are “waking up”
No significant metabolism by the liver or kidneys
• Not stored in the tissues
Fear Reduction & N2O
• One group treated with behavior management only;
• other group with behavior management and N2O.
• Dental treatment of highly fearful children is carried out more
successfully with N2O during the first few sessions.
• N2O is thus a valuable aid for making highly fearful children treatable
quickly.
• When highly anxious children are treated with nitrous oxide for a
number of consecutive sessions, their anxiety remains significantly
lower during a following control period, even without use of nitrous
oxide.
Four Stages of Anesthesia
• Analgesia
• patient is conscious
• reflexes are intact
• Delerium
• Surgical Anesthesia
• Respiratory Paralysis
• In analgesia stage, the patient is
conscious, has all vital reflexes intact, can
communicate and cooperate with the
dentist, and quickly returns to a normal
state following a few minutes of
oxygenation.
N2O Should Be Used To:
• Ease fears and anxieties
• Aid in the treatment of special patients
• Increase tolerance for longer appointments
• Raise the pain reaction threshold
N2O Should Not Be Used To:
• uncontrolled behavior
• Control pain by replacing local anesthesia
• Replace poor techniques of behavior management
Administration of N2O
• 5 - 6 liters O2
• Increase N2O gradually; watch for stages of analgesia
• Maintenance about 40% -50%
• Reduce N2O with long procedures
• Record N2O levels in the chart
• 3 - 5 minute O2 flush
• Rapid induction technique
• 1. Open both tanks (O2 and N2O)
• 2. Turn the On/Off switch to On
• 3. Adjust the green (O2) and blue (N2O) levers to administer a 50/50
mixture of oxygen and Nitrous Never turn on the gases until the mask
is sealed on the patients face! …
• Begin with a 20/80 mix of N2O and O2 and titrate to achieve desired
level of sedation/anxiolysis
• Nitrous oxide may be administered to a maximum of 60% Remember
the patient is not “asleep”
• Patient should appear calm and relaxed
Administration of N2O/O2
Titration is an important skill in
administering nitrous oxide.
Titration is a method of administering a
drug in incremental amounts until a
desired endpoint is reached. If done
properly, the patient does not receive
more of the drug than is necessary.
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Administration of N2O/O2
Advantages of N2O titration
• Only the amount of drug
required by the patient is
given.
• Allows for individual
biovariability
• Uncovers idiosyncratic
reactions early
• Minimizes negative
experiences with over
sedation
Potential side effects of nitrous oxide
• Detachment / disassociation from environment
• Dreaming, hallucinating, or sexual fantasizing
• Out-of-body experiences
• Floating and/or flying
• Physical body movements may become restless, combative,
sluggish
• Inability to move, communicate, or keep mouth open
• Words may be slurred or repeated; incoherent sentences
Potential side effects of nitrous oxide
• Humming or vibrating sounds that progressively worsen
• Fits of uncontrolled laughter
• Patient may experience:
• Drowsiness
• Dizziness / Light headedness / spinning sensations
• Diaphoresis
• Nausea / vomiting
• Fixed eyes
• Uncomfortable body warmth
• Unconsciousness
Contraindications for use of N2O/O2 sedation
• N2O rapidly replaces N2 in air filled spaces in the body causing
expansion of those spaces; therefore, N2O/O2 should not be used in
patients with:
• Pneumothorax
• Middle ear occlusion/surgery
• Recent (within 3 weeks) craniotomy/pneumoencephalography
• Increased intracranial pressure
• Intraocular injury/surgery (injected gas may last up to 10 weeks)
• Maxillofacial injuries
• Intestinal obstruction
• Cystic fibrosis
Contraindications for use of N2O/O2
sedation
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Current upper respiratory tract infection
Chronic obstructive pulmonary diseases
Vitamin B12 deficiency
Psychological impairment
Phobic individuals
Bleomycin therapy
Current psychotropic drug use
Current or recovering drug use/addiction
First trimester of pregnancy
Any facial injury which would prevent use of the mask
Note: Asthma is not a contraindication
Potential biohazards of N2O for health professionals
• No direct evidence suggests any causal relationship between chronic
low-level exposure to N2O and potential biologic effects.
• The following preventive measures to reduce or eliminate trace gas
contamination are encouraged:
• Operate a delivery system with scavenging capabilities, accurate
flow meter, adequate vacuum, and a variety of mask sizes.
• Maintain a ventilation system to include vent exhaust to outside and
fresh air exchange when possible.
• Maintain an adequate suction system – ensure vacuum, use
appropriate size mask, discourage patient talking.
• Inspect cylinder attachments, lines, hosing, and reservoir bag for
leaks.
• Calibrate flow meters every 2 years.