Sedation and GA BRIEF questions

Question 1

Briefly what are the stages of NO sedation?

Question 2

At what stage and planes do we have to stay within during NO sedation?
What is this sedation level known as?
What is this level of analgesia known as and why?

Answer 2

-Stage 1, Plane I and II
-Conscious Sedation (No loss of consciousness - pt is aware but relaxed)
-Relative Analgesia (only partial analgesic effect

Question 3

what is the dose to achieve conscious sedation, and what is the dose to maintain it with NO?

Answer 3

40-50%, then 20-25% to maintan

Question 4

What happens in Stage 1 Plane I NO sedation?

Answer 4

• Increased pain threshold
• Vitals intact
• Reflexes unaffected
• paraesthesia (tingling sensation on lips, fingers, toes)
• feeling relaxed
  -Conscious communication
  -Vasomotor - feeling of warmth

Question 5

What happens in Stage 1 Plane II sedation?

Answer 5

Same as stage 1 plane I, +
- further relaxation
- floaty, euphoric feeling
- reduced blink rate
- reduced pharyngeal reflex
- can maintain open mouth
- may have some amnesia + telescoping of time (can be beneficial)
- may have flushing of face or extremeties

Question 6

How may you be able to tell if a pt is going into Stage 1 plane III?

Answer 6

-may not be bale to maintain open mouth
- may be sleepy, sweaty or nauseous
- may not respond verbally to painful stimuli
- reduced pharyngeal and laryngeal reflexes

Question 7

Should you do NO sedation in a pt with air filled cavities (Eg. Ear infection, bowel obstruction) and why?

Answer 7

No
-NO has a very low blood-gas solubility ratio compared to nitrogen (15-30x quicker)
-the air-filled cavities will have nitrogen in them
-> NO enters the cavity 15-30x quicker than nitrogen, which can cause pressure/volume increases in the cavity

Question 8

Does NO biotransform in the body when it is inhaled?

Answer 8

No, there is no biotransformation in the body
Low blood-gas solubility -> has rapid onset and recovery
It is excreted Unchanged via the lungs

Question 9

Can you use NO in a pregnant patient?

Answer 9

Yes, but avoid in 1st Trimester
(NO passes readily through placenta)

Question 10

Indications for nitrous oxide sedation

Answer 10

• able to cooperate with tx (masks and instructions)
• mild-moderate fear or anxiety
• sensitive gag reflex
• intolerance to long appointments

Question 11

What are TRUE contraindications for nitrous oxide sedation?

Answer 11

• Airway blockage (eg. cold, obstructed passage)
• Psychiatric disorder (can’t judge whether their reactions are due to NO or not)
  -Bleomycin chemotherapy
• MTHFR* deficiency

Question 12

What are some cautions / relative contraindications for NO use?

Answer 12

• Pre-cooperative child (<3yo)
• uncooperative pt
• requiring extensive or very complex tx
• Conditions with trapped gas (eg. ear infection, bowel obstruction)
  -Claustrophobic
  -significantly medically compromised
  -Pregnancy 1st trimester
• Pt at risk of bone marrow suppression from NO - eg. Vit B 12 or Folate deficiency

Question 13

How do you end the course of NO sedation? why?

Answer 13

administer 100% oxygen for 3 mins and seat the child for a few mins after the procedure

to prevent diffusion hypoxia (although, it is not a significant clinical problem)

Question 14

what can cause complications with NO sedation?

Answer 14

-over-sedation
-lack of monitoring
-interactions with other medications

Question 15

what are some possible adverse reactions to NO?

Answer 15

-nausea and vomiting
-dizziness, light headedness
-over-sedation
-Hypoxia
-Pressure/volume change in gas-filled cavities
-bone marrow suppression from chronic use

Question 16

what is an occupational hazard of the use of NO?

Answer 16

chronic exposure can cause haematopoiesis and myeloneuropathic disorders

Question 17

Advantages of NO

Answer 17

-non-invasine
-safe when administered correctly
-mild analgesia
-anxiolytic/sedative
-minimal impact on reflexes
-Vitals intact
-easily titrated
-rapid onset and recovery

Question 18

Disadvantages of NO

Answer 18

-need cooperation with mask
-mask can interfere with procedure
-continuous administration - need to monitor
-possibility of occupational hazard
-may still need behaviour management
-cost for the practice

Question 19

Indications for Oral sedation?

Answer 19

-anxiety
-co-operative
-when other routes are undesirable / not possible

Question 20

Contraindications of oral sedation

Answer 20

-unable to take medication
-medical issues/interactions
-use w precaution in children under 6

Question 21

Indications for IV sedation

Answer 21

-anxiety
-invasive procedure of short duration (eg. one exo)

Question 22

contraindications for IV sedation

Answer 22

-inability to tolerate IV access
- medical issues or interactions
-use w precaution in children under 6

Question 23

some examples of sedative agents used

Answer 23

-benzodiazepines
-antihistamines
-opioids
-ketamine
-barbiturates

Question 24

Indications for GA for paediatric dentistry?

Answer 24

-very anxious child
-moderate - extremely uncooperative
-lack of cooperation due to psychological or emotional maturity
-not responsive to other modes of behaviour management
-extensive surgical treatment
-when prompt tx of acute condition is required (eg. dental abscess threatening patency of airway)

Question 25

contraindications for GA in paeds pts

Answer 25

-medical issues where risk outweigh benefits

Question 26

Is GA safe for paeds pts?

Answer 26

is regarded extremely safe, however, there can always be risks

Question 27

How should you tx plan if a child is requiring GA?

Answer 27

Effort should be made that there be only one GA
-> tx planning should take the GA session into account