Inhalation Sedation Flashcards
Read articles
Read articles
What is conscious sedation
- Technique that produces a state of central nervous system depression to enable treatment to be delivered
- But during which verbal contact with the patient is maintained throughout the period of sedation
Use SDCE guidelines
Use
What can the patient do during conscious sedation
- They are conscious
- Independently retains protective reflexes and a stable patent airway
- Understands and repsonds to verbal stimuli throughout
Examples of conscious sedation
- Inhalation sedation
- oral
- Transmucosal (nasal)
- Intravenous
Aims of conscious sedation for the child
- Prevent and reduce dental fear, anxiety and procedure associated pain
- Facilitate cooperation
- Promote a positive attitude and response to treatment
Aims of conscious sedation for the dentist
- Facilitate safe provision and completion of quality care by minimising disruptive behaviour
- Leave child fit for safe discharge at end of treatment
Options for managing dental anxiety
- Behaviour management
- Behaviour therapy
- Conscious sedation
- GA
Indications of IHS
- Manageent of mild anxiety
- Gag reflex
- Medically compromised patients
- Traumatic procedures
Contraindications of IHS
- Upper respiratory tract issues
- Blocked nose
- Medical contras
- Pre cooperative children
What gas(s) is used in IHS
- Nitrous oxide
- With oxygen
Pharmocology of nitrous oxide
- Colourless and virtually odourless gas
- Insoluble
- rapidly excreted by the lungs
- Much more soluble than nitrogen in blood (diffusion hypoxia therefore may occur)
- Euphoria and CNS depressant effect. Decreases memory, concentration and intelligence
- Minimal effect on respiratory system
- Non-irritant to mucosa
- Minor decrease in cardiac output
- Slight increase in peripheral resistance thereby maintaining blood pressure
What kind of med comp pts is ihs good at treating and why
- Cerebrovascular system disorders
- Minor decrease in cardiac output
- Slight increase in peripheral resitance so maintains BP
3 main modes of actions of NOS
- Analgesic effect: works on opioid receptors
- Anxiolytic effect: resembles that of benzodiazepines, initiated at GABA receptors
- Anaesthetic effect: GABA receptors
Aims of N2o
- Reduce or eliminate anxiety
- Reduce untoward movement and reaction to dental tx
- Enhance communication and pt cooperation
- Raise pain reaction threshold
- Increase tolerance for longer appointments
- reduce gag
- Aid in tx of medical compromised its
Safety checks for ihs
- Plug oxygen and nitrous tubing
- Make sure all fitting nicelyy and not loose
- Turn moisture to 100% ox and flow meter to 6l/min
- Check that nitrous oxide is 0
- Change mixture to 50 and see how it changes
- Stop common gas outlet with balm of hand and press oxygen flush. Bag should inflate. No leaks
- If you pull out oxygen check both go to 0
Medical Contras to IHS
- Nasal obstruction/congestion
- Severe forms of respiratory disease (COAD, emphysema)
- Middle ear disease/infections
- Neuromuscular disorders (MS, 3myasthenia gravis)
- Porphyria (enzyme disorder)
- anti-folate meds eg. methotrexate
- bleomycin chemotherapy
Pre-op checks
Consent form signed Med history Nasal congestion Chaperone should be present throughout Nasal hood allow a good seal
Sensations of ihs
Floating
Tingling of fingers and toes
Heaviness or lightness
Technique in terms of increments
- Incremental increase of nitrous oxide in 5-10% increments
- Monitor patients breathing
- Calm monotone voice
- Encourage nasal breathing
- Use rubber dam to protect airway
- 100% oxygen for 3-5 mins to prevent diffusion hypoxia at the end of treatment
Signs and symptoms of ideal sedation
Signs:
- Slightly increased BP and HR initially
- Normal and smooth respirations
- Peripheral vasodilation
- Flushing of extremities and face
- Decreased muscle tone as anxiety decreases
- Arms and legs relax
Symptoms
- Light headedness
- Tinging of hands and feet
- Wave of warmth
- Feeling of vibration throughout the body
- Numbness of the hands and feet
- Numbness of oral soft tissues
- Euphoric feeling
- Analgesia
- Lightness of extremities
What should u monitor during tx
- Responsiveness
- Colour
- Respiratory rate
- Rhythm
what is the main post complication of nitrous oxide
- Diffusion hypoxia
- During the recovery period
- rapid release of nitrous oxide from blood stream into alveoli thereby diluting concentration of oxygen
- Reduces alveolar oxygen tension, which then produces hypoxia
- May lead to headache, disorientation, nause and can be avoided by administering 100% oxygen spot treatment
What should be documented in the notes
- Name of assistant
- Name of escort
- Time of administration
- Tidal flow
- Proportion of N20/O2 reached
- Amount of o2 given /
- State of patient during
- State of patient after
- Time of departure
Reasons for failure and management
Mouth breathing instead of nose breathing
- Encourage nose breathing
- Ensure not blocked
No effective seal around nosepiece
-Adjust so effectively fitting
Too anxious and not able to cooperate
-Stop and consider other options
Fault in machine
-Stop and check equipment
Resisting the effect
- USe BM techniques
- Consider other options
Advantages of IHS
- Non invasive and well tolerated
- Easily titratable and adjust level of sedation
- Wide margin of safety if used by suitably trained operator
- Rapidly absorbed (2-3 mins onset)
- Rapidle eliminated (5 mins complete recovery)
- Minimal impairment of reflex
- Reduced anxiety to follow ups
- Some analgesic effect
- Cost effective alternative to GA
- Reduces awareness of pain
Disadvantages of IHS
- Lack of potency
- Relies on psychological reassurance
- Nasal mask may impede access
- Effective nasal breathing requires
- Nitrous oxide pollution
- Variable post op amnesia
- LA still required
Potential adverse effects of IHS
- HEadahces, nausea and vomiting up to 10%
- Loss of consciousness
- Unfavourable psychological reactions
Chronic exposure effects (usually occupational)
Haematological effects
-Impaired RBC production and pernicious anaemia
Reproductive effects
- Avoid in pregnancy
- Offer pregnant staff choice
- Exposure to N20 should not exceed 100ppm for an 8 hour period
How can nitrous oxide pollution be reduced
- Active scavenging systems
- Good ventilation
- Floor level extractor fans
- Good technique with the patient
- Equipment that has been checked and serviced on a regular basis
