When GA is required for young patients Flashcards
What is GA?
Any technique using equipment or drugs which produces a loss of consciousness in specific situations associated with medical or surgical interventions
loss of consciousness or abolition of protective reflexes
How does GA work?
Anaesthetic agents produces anaesthesia by depressing specific areas of the brain
How does inhaled GA work?
Inhaled agents enter through lungs, distributed 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 the CNS.
How does intravenous GA work?
Intravenous agents given straight into circulation, distributed through body and reach specific sites in CNS by crossing the blood brain barrier.
Anatomically what are distinctions in child anatomy?
Large head, short neck, large tongue
Narrow nasal passages
Are obligate nasal breathers at
birth
High anterior larynx
Larynx narrowest at cricoid cartilage
Large floppy epiglottis
Physiologically what are the distinctions in child anatomy?
Low functional residual capacity (FRC)
Closing volume is greater than FRC up to 5years of age, leading to increased ventilation/perfusion (V/Q) mismatch
Horizontal ribs, weak intercostals muscles leading to relatively fixed tidal volume
Oxygen consumption is high 6ml/kg/min compared to 3ml/kg/min in adults
What are the distinctions in the child nervous system?
Increased incidence of periodic breathing and apnoea
Ventilatory response to CO2 is more readily depressed by opiates
Immature neuromuscular junction leads to increased sensitivity to muscle relaxants
What are the distinctions in the child temperature regulation?
High surface area to body weight ratio
Large head surface area and heat loss
Require a higher temperature for a thermoneutral environment
Immature responses to hypothermia (poor shivering and vasoconstriction)
Brown fat metabolism which increases oxygen consumption
Nervous System
What are common inhaled agents?
nitrous oxide
sevoflurane (agent of choice for induction)
halothane
isoflurane
desflurane
What are common intravenous agents?
propofol (used for induction and in some situations for maintenance)
What is used to keep the airway open?
LMA (laryngeal mask airway)
Nasal endotracheal intubation
Oral endotracheal intubation
What is used in any type of airway?
throat pack
A throat pack is a piece of absorbent cotton or gauze placed in the back of the throat during oral or dental surgery. Its primary purpose is to:
Prevent aspiration: This means stopping foreign objects like blood, saliva, or small pieces of tissue from entering the lungs.
Maintain a clear surgical field: By absorbing fluids, it keeps the surgical area clean and visible.
What are the stages of anesthesia?
Stage 1: Induction
Stage 2: Excitement
Stage 3: Surgical Anaesthesia
Stage 4: Respiratory Paralysis/ Overdose
What phase is very dangerous to enter?
stage 4 - respiratory paralysis/overdose
What are GA indications?
Child needs to be asleep for treatment because there is a belief that they are too young, too anxious, or too uncooperative to accept treatment any other way i.e. the child needs to be fully anaesthetised
OR
Dentist needs patient to be guaranteed to be completely still, operation is complex i.e. the surgeon needs the child to be fully anaesthetised
What are GA contraindications?
risks of procedure do not outweigh the benefits
What are the major risks of GA?
Serious outcome/ major adverse event 1:400,0000, 3 in a million
Death, will not wake up again, brain damage
What are the minor/common risks of GA?
Common
Pain
Headache
Nausea, vomiting,
Sore throat
Sore nose/ nose bleed
Drowsiness
Upset
Increased anxiety about future dental treatment
Risks from treatment - pain, bleeding , swelling, bruising, loss of space, visible restorations, restorations may be lost/ fail/wear through, stitches
What are potential complications that may occur due to GA?
Damage to mouth/ oropharynx from intubation
Minor idiosyncratic/ allergic reactions- nausea and vomiting
Malignant hyperpyrexia (rare! But VERY important to ask re FH of this!!! Needs specific care)
Slow recovery from anaesthetic
Prolonged apnoea after muscle relaxant (suxamethonium)
“awareness”- paralysed but not effective anaesthesia
Laryngospasm
Coughing/moving during procedure- anaesthetic too light during stimulation e.g. extractions
Prolonged bleeding intra- operatively or bleeding post-op
What documentation must be completed for safety?
WHO Surgical Safety Checklist
Brief before list, debrief after
For every patient every time:
Sign in
Time Out
Sign Out
Why is dental treatment on the lower arch during GA more difficult?
During dental treatment (especially extractions on lower arch) mandible can easily fall or be pushed backwards and the chin onto the chest—obstructing airway!!!!!! Dentist must be aware of this and lift mandible or anaesthetist/ assistant may help to hold mandible forward
What medicial conditions require careful work up for GA?
sickle cell disease
down’s syndrome
bleeding disorders
cardiac conditions
renal disease
diabetes
liver disease
cystic fibrosis
severe asthma
epilepsy
What is the discharge criteria for post-op
Fully conscious, able to maintain clear airway, exhibits protective
reflexes
Satisfactory oxygenation and respiration
CVS stable- no unexplained cardiac irregularities, no persistent bleeding, pulse and BP acceptable, adequate peripheral perfusion
Pain, nausea and vomiting controlled
Temperature in normal limits
Eaten, drunk, been to toilet
What are the satisfactory respiration values?
2-5yrs 24-30 breaths/min
5-12yrs 20-24 breaths/min
