Inhalation Sedation

Question 1

When was modern Inhalation Sedation founded and who gave the first course

Answer 1

1949
Harry Langa

Question 2

Who described the analgesic properties of nitrous oxide in 1799?

Answer 2

Humphrey Davey

Question 3

indications for inhalation sedation

Answer 3

adults and children
- anxiety
- needle phobia
- gagging
- traumatic procedures
- medical conditions aggravated by stress
- unaccompanied adults requiring sedation

Question 4

inhalation sedation contraindications

Answer 4

• common cold
• tonsillar/adenoidal enlargement
• severe COPD
• first trimester of pregnancy
• fear of ‘mask’/claustrophobia
• patients with limited ability to understand
• obstruction of the operating field by mask

Question 5

inhalation sedation - equipment

Answer 5

gas cylinders
pressure reducing valves
flow control meter
reservoir bag
gas delivery hoses
nasal hood
waste gas scavenging system

Question 6

gas delivery hoses - function

Answer 6

one hose delivers fresh gases from machine
one hose delivers waste gases to scavenging system
single use

Question 6

reservoir bag features

Answer 6

2 or 3 litre bag - rubber or silicone
smaller bag available
should move visibly with each inspiration and expiration
- most not collapse
helps to monitor respiration

Question 7

features of the nasal mask/hood

Answer 7

comes in various sizes
should form a seal around patients nose
2 connections to breathing circuit

Question 8

Scavenging system 0 outline

Answer 8

active scavenging of waste gases
- small negative pressure
change in surgery air reduces nitrous oxide levels
watch for patient mouth breathing
- check mask seal to reduce contamination
- rubber dam uses decreases likelihood of mouth breathing

Question 9

inhalation sedation safety features

Answer 9

air entrapment valve
oxygen flush button
oxygen monitor
reservoir bag
colour coding
scavenging system
oxygen and nitrous oxide pressure dials
pressure reducing valves
one way expiratory valve
quick fit connection for positive pressure oxygen delivery

Question 10

inhalation sedation advantages

Answer 10

rapid onset
- 2-3 mins
rapid peak action
- 3-5 minutes
flexible duration
rapid recovery
few side effects on patient
drug not metabolised
some analgesia
no amnesia

Question 11

inhalation sedation disadvantages

Answer 11

equipment expensive
gases expensive
space occupying equipment
environmental concerns
requires ability to brave through nose
staff addiction
difficult to accurately determine actual dose

Question 12

signs of adequate inhalation sedation

Answer 12

patient relaxed/confortable
patient awake
reduced blink rate
laryngeal reflexes unaffected
vital signs unaffected
gag reflex reduced
mouth open on request
decreased reaction to painful stimuli
decrease in spontaneous movements
verbal contact maintained

Question 13

symptoms of adequate sedation

Answer 13

mental and physical relaxation
lessened awareness of pain
paraesthesia
- lips, fingers, toes, legs, tongue
lethargy
euphoria
detachment ‘floating feeling’
warmth
altered awareness of passage of time
dreaming
small controllable ‘fit of the giggles’

Question 14

signs and symptoms of over sedation

Answer 14

repeated mouth closing
spontaneous mouth breathing
irrational and sluggish responses
decreased cooperation
incoherent speech
uncontrolled laughter
patient no longer enjoying the effects

Question 15

inhalation sedation - pre operative instructions

Answer 15

have a light meal before appointment
take routine medicines as usual
children accompanied by a competent adult
adults accompanied at their first sedation appointment afterwards may then attend alone
do not drink alcohol on day of appointment
wear sensible clothing
arrange care of children during and after appointment
plan to remain in Clinic for up to 30 minutes after treatment

Question 16

inhalation sedation technique prior to positioning the hood on patient’s nose

Answer 16

set up the machine
select nasal hood
connect to hoses
set mixture dial to 100% oxygen
settle patient in dental chair
reinforce explanations of procedure
set flow to 5-6l per minute
position hood on patients nose

Question 17

inhalation sedation techniques - steps once hood is positioned on patient’s nose

Answer 17

encourage nasal breathing
check reservoir bag movement
- small movements = check seal and look for mouth breathing and/or decrease flow
- movement too great - increase flow rate
patient to be comfortable with hood before proceeding - about 1 minute
- ask patient to signal when they begin to feel different
- reduce oxygen by 10%
- wait 1 minute and repeat
- after 80% o2 reduce by 5% per minute
stop titration when patient ready for treatment

Question 18

what to do if patient is over-sedated

Answer 18

increase oxygen in 5-10% increments until satisfactory sedation

Question 19

patient is under-sedated - what should you do?

Answer 19

decrease oxygen in 5% increments until satisfactory sedation

Question 20

inhalation sedation - recovery - steps

Answer 20

gradually increase oxygen by 10-20% per minute until 100%
administer 100% oxygen for 2-3 minutes to prevent diffusion hypoxia
remove hood and turn gas flow off
return patient to upright slowly, give praise and reassurance

Question 21

inhalation sedation - success rate and influences

Answer 21

success rate 50-90% according to published data
- greater success for orthodontic extractions
poorer in patients with pain
success depends on appropriate patient assessment and sedation

Question 22

steps following completion of treatment after inhalation sedation

Answer 22

adult patients may leave unaccompanied at dentist’s description
child patients (u16s) must be accompanied by a competent adult
prior to discharge, ask patient how they felt procedure went
patients may feel shivery after IS
- reassure patient that this is common and passes quickly