general anaesthesia for dental treatment in children Flashcards
(42 cards)
1
Q
what is the definition of general anaesthesia
A
- any technique using equipment or drugs which produces a loss of consciousness in specific situation associated with medical or surgical interventions
- loss of consciousness or abolition of protective reflexes
2
Q
what percentage of hospital elective procedures with GA are for dental extractions
A
- around 25%
3
Q
how to anaesthesia agents produce anaesthesia
A
- by depressing specific areas of the brain
4
Q
how do inhaled GA work
A
- enter through the lungs, distribute to tissues by the circulation
- reach specific sites in the central nervous system by crossing the blood brain barrier
- magnitude of CNS depression is proportional to partial pressure as they reach CNS
5
Q
how to intravenous GA work
A
- given straight into circulation
- distributed through body and reach specific sites in CNS by crossing blood brain barrier
6
Q
what is the anatomy to be aware of in a child
A
- large head, short neck
- narrow nasal passages
- high anterior larynx
- larynx narrowest at cricoid cartilage
- large floppy epiglottis
7
Q
what causes CROOP in children
A
- large floppy epiglottis
8
Q
what is respiratory physiology to be aware of in children for GA
A
- low functional residual capacity (FRC)
- closing volume is greater than FRC up to 5, leading to increased perfusion/ventilation mismatch
- horizontal rids, weak intercostal muscles leading to relatively fixed tidal volume (can’t increase)
- oxygen consumption is high (6ml/kg/min)
9
Q
what is the normal oxygen consumption in adults
A
- 3ml/kg/min
10
Q
what are some temperature regulation things to be aware of in children for GA
A
- high surface area to body weight
- large head surface area and heat loss
- require higher temperature for a therm-neutral environment
- immature response to hypothermia (poor shivering and vasoconstriction
- brown fat metabolism which increase oxygen consumption
11
Q
what does brown fat metabolism do
A
- uses a lot more oxygen which is why children’s oxygen consumption is so much higher than adults
- adults don’t have brown fat metabolism
12
Q
what is some nervous system things to be aware of in children for GA
A
- increased incidence of periodic breathing and apnoea’s (irregular breathing)
- ventilatory response to CO2 is more readily depressed by opiates (sensitive to muscle relaxants)
- immature neuromuscular junction leads to increased sensitivity to muscle relaxants
13
Q
what are some common drugs for GA
A
- inhaled agents = nitrous oxide, sevoflurane, halothane, isoflurane, desflurane
- intravenous agents = propofol
14
Q
how decides on what drugs are sued for GA
A
the anaesthetist
15
Q
what does the drug choice depend on
A
- length of procedure
- patient preferences
- medical history
- previous GA experience
- anaesthetist’s recommendations
- equipment
- staff and other resources
16
Q
what are the types of airway used in GA
A
- LMA = laryngeal mask airway (most common)
- nasal endotracheal intubation = tube not in mouth so better for access
- oral endotracheal intubation =
17
Q
what do airways need for GA
A
- throat pack
- some gauze that you pack around tube when working towards the back of the mouth way from where you are working so it will catch saliva and water and blood during procedure
18
Q
what are the stages of anaesthesia consciousness
A
1 = induction 2 = excitement 3 = surgical anaesthesia (what you want) 4 = respiratory paralysis/overdose
19
Q
what happens in stage 2 of GA that parents need to be warned about
A
- patient may move around
- parents may think it is child trying to get away but it is not
- happens more with inhalation induction
20
Q
what are the 2 main indications for the use of GA
A
- child needs to be asleep for treatment because there is a belied that they are too young/anxious or uncooperative to accept treatment any other way
- dentist need patient to be guaranteed to be completely still, operation is complex
21
Q
what are the contraindications of doing GA
A
- risks of procedure do not outweigh the benefits
22
Q
what are the major risks of GA
A
- rare
- death
- brain damage
- need to be very sensitive in discussing this with parents beforehand
23
Q
what are the minor risks of GA
A
- common
- pain
- headache
- nausea, vomiting
- sore throat
- sore nose/nose bleed
- drowsiness
- upset
- increased anxiety about future dental treatment
- usual risks from the treatment itself
- damage to mouth/oropharynx from intubation
- minor idiosyncratic/allergic reactions
24
Q
what is malignant hyperpyrexia
A
- rare but very important to ask about in family history
- allergic reaction to inhaled anaesthetic
- needs specific care
25
what can be an effect but it not very common in children
- prolonged apnoea after muscle relaxant
- suxamthonium causes it
- don't really see in young people as they are more sensitive to it
26
what is a laryngospasm
- happens when something irritates the airway
- not nice to see
- irritation to airway os larynx spasms to throw head back
- not awake
27
what does it mean if patient starts coughing/moving during procedure
- anaesthetic wearing off
| - tends to happen as we do more stimulated things last
28
what needs to be done before patient has GA
- WHO surgical safety checklist
- need to introduce the whole team to the patient before
- agreed protocols to summon help if needed
- need other staff ready incase of emergency
- check machine and medication
29
what must you be careful with the airway
- shared airway with dentist and anaesthetist
- need to not over extend neck
- mandible can easily fall or b pushed backwards and the chin onto the chest = this obstructs the airway
- need to have mandible supported
30
how can GA risks be minimised
- do less procedure
- may be possible to join with other specialities when they are doing GA on patient
- but some won't let us as the mouth is not a clean environment
31
what are some medical conditions that require careful work for GA
- sickle cell disease
- down's syndrome
- bleeding disorders
- cardiac conditions
- renal disease
- diabetes
- liver disease
- cystic fibrosis
- severe asthma
- epilepsy
32
what can happen with a patient with sickle cell disease getting GA
- can have a crisis if not managed well
33
what needs to be aware of with a patient with Down's syndrome for GA
- may have an unstable atrial joint and need to not cause paralysis ?
34
what is the discharge criteria
- fully conscious, able to maintain airway, exhibits protective reflexes
- satisfactory oxygenation and respiration
- CVS stable (no irregularities no persistent bleeding, pulse and BP acceptable)
- pain, nausea and vomiting controlled
- temperature in normal limit s
- eaten, drunk been to toilet
- need to stay for around 2 hours after procedure
35
what is satisfactory oxygenation and respiration rates for discharge
- 2-5-yrs = 24-30 breaths/min
| - 5-12-yrs = 20-24 breaths/min
36
what are the post-op instructions
- pain control
- travel home = no public transport
- rest/quiet play
- monitoring
- look out for pain/bleeding
- extraction advice
- soft diet
- prevention
- follow up
- discharge letters
37
when should consent for GA begin
- first stage of consent should ideally be done on a separate day before the operation to give parents and child time to fully understand all the risks, benefits and alternatives to give them time to ask questions
- advise that the 1st appointment will be for treatment planning only and that plan may change
38
what must be included in the pre-op instructions
- pre-op preparation including fasting, proposed treatment, GA procedure, adult escort with no other children, post-op arrangements, post-op care and pain control
- can give booklets with all this information
39
who can consent for children
- mother automatically has responsibility
- father has ability if married to mother at Childs birth (in England/Wales/NI) or conception (Scotland)
- unmarried father if named on birth certificate (by 04/05/2006 in Scotland)
- unmarried father who child registered before these dates or who is not mentioned on birth certificate then need to acquire responsibility
- adoptive parents
- married stepparents can acquire it
- legally appointed guardian
- person with residence order concerning child
- local authority
- social services if not legal guardian
- foster parents don't have it but could in emergency
40
can child give consent
- children under the age of 16 can consent to medical treatment if they have sufficient maturity and judgement to enable the to fully understand what is proposed
41
what should be included in the referral letter for GA
- patient name
- patient address
- patient/parent contact number
- patient medical history
- patient GP details
- parental responsibility
- justification for GA
- proposed treatment plan
- previous treatment details
- recent radiographs or if not available an explanation as to why
42
who's responsibility is the referral letter
- responsibility of the primary referring practitioner
| - need to make sure referral letter is good and has all the necessary information
