What is the formula for ETT size in children?

For cuffed tubes: Age/4 + 3.5 (for children over 2 years). For uncuffed tubes: Age/4 + 4. Modern practice favours cuffed tubes even in infants when cuff pressure is monitored (less than 20-25 cmH2O).

Why is the paediatric airway more difficult to manage?

Children have a large occiput causing neck flexion, relatively large tongue, omega-shaped epiglottis, anterior/cephalad larynx, narrow subglottic region (cricoid ring), and shorter trachea with higher oxygen consumption leading to rapid desaturation.

What is the drug of choice for RSI in a child with raised ICP?

Thiopentone (3-5 mg/kg) or propofol (2-4 mg/kg) for cerebral protection. Ketamine (1-2 mg/kg) is acceptable and preferred if haemodynamically unstable. Rocuronium (1.2 mg/kg) preferred over suxamethonium unless contraindicated.

When should you perform needle cricothyroidotomy vs surgical cricothyroidotomy in children?

In children under 8-10 years, needle cricothyroidotomy with jet ventilation is preferred due to smaller cricothyroid membrane. Surgical cricothyroidotomy is acceptable in older children/adolescents. Time-limited oxygenation only.

Paediatric Airway Management

Quick Answer

One-liner: Paediatric airway management requires understanding of critical anatomical differences (large occiput, anterior larynx, omega-shaped epiglottis, narrow subglottic cricoid ring), age-appropriate equipment sizing, and recognition that children desaturate rapidly due to high metabolic rate and low FRC.

The paediatric airway differs fundamentally from the adult airway in anatomy, physiology, and pathology. Children are NOT small adults. The key anatomical differences include a large occiput causing neck flexion in the supine position, a relatively large tongue, an omega-shaped floppy epiglottis, an anterior and cephalad larynx (C3-4 vs C5-6 in adults), and a narrow subglottic region at the cricoid cartilage (the narrowest point in children under 8 years). Physiologically, children have higher oxygen consumption (6-8 mL/kg/min vs 3-4 mL/kg/min in adults) and lower functional residual capacity, leading to rapid oxygen desaturation during apnoea. These factors mandate meticulous preparation, appropriate equipment sizing, and anticipation of the difficult paediatric airway [1,2,3].

ACEM Exam Focus

Primary Exam Relevance

Anatomy: Paediatric airway differences (occiput, tongue, epiglottis, laryngeal position, cricoid ring, tracheal length), cricothyroid membrane dimensions in children, nerve supply to larynx, neck zones [3,4]
Physiology: Oxygen consumption, functional residual capacity (FRC), closing capacity, safe apnoea time (infants 30-90 seconds vs adults 3-8 minutes), desaturation curve, work of breathing, lung compliance [5,6]
Pharmacology: Weight-based dosing of RSI agents (propofol, ketamine, rocuronium, suxamethonium), sugammadex dosing, opioid doses, atropine for vagal prevention [7,8]

Fellowship Exam Relevance

Written: SAQs on paediatric RSI drug doses, croup vs epiglottitis differentiation, foreign body management algorithm, difficult paediatric airway prediction [9,10]
OSCE: Resuscitation stations with paediatric airway emergency, bag-mask ventilation technique, equipment sizing demonstration, communication with parents, croup management [11]
Key domains tested: Medical Expert, Communicator, Collaborator, Leader, Cultural Competence

Key Points

Clinical Pearl

The 7 things you MUST know about paediatric airway:

Large occiput causes neck flexion in supine position - use shoulder roll in infants
Anterior/cephalad larynx (C3-4) - use straight blade (Miller) in infants, lift epiglottis directly
Cricoid ring is the narrowest point (not vocal cords) - uncuffed tubes traditionally used, but cuffed tubes now acceptable with pressure monitoring
Rapid desaturation - infants desaturate within 30-90 seconds of apnoea; preoxygenate meticulously
ETT size formula: Cuffed = Age/4 + 3.5; Uncuffed = Age/4 + 4; have sizes above and below ready
Needle cricothyroidotomy preferred in children under 8-10 years (small CTM); surgical in older children
Oxygen delivery before intubation - croup responds to nebulised adrenaline; epiglottitis requires minimal handling

Epidemiology

Metric	Value	Source
Difficult intubation (paediatric ED)	2-4% of all intubations	[12]
Difficult BMV in children	1.7-6.6%	[13]
Failed intubation (paediatric anaesthesia)	0.3-1.0%	[14]
Croup incidence	3% of children under 6 years annually	[15]
Epiglottitis incidence (post-Hib vaccine)	0.6-1.0 per 100,000 children	[16]
Foreign body aspiration	17,500 presentations/year (USA), peak age 1-3 years	[17]
Cardiac arrest secondary to airway	70-80% of paediatric cardiac arrests	[18]

Australian/NZ Specific Data

RCH Melbourne Guidelines: Gold standard for Australian paediatric practice; regularly updated RSI protocols and equipment sizing charts [19]
Paediatric Research in Emergency Departments International Collaborative (PREDICT): Australian/NZ network providing ED paediatric evidence [20]
Remote/Rural: RFDS retrieval data shows higher paediatric airway complication rates in resource-limited settings - telemedicine guidance recommended [21]
Indigenous populations: Higher rates of bronchiolitis, pneumonia, and croup in Aboriginal and Torres Strait Islander children; Maori children in NZ similarly affected - requires culturally safe care and interpreter services [22,23]

Paediatric Airway Anatomy

Critical Anatomical Differences

Feature	Infant/Young Child	Adult	Clinical Implication
Occiput	Large, prominent	Proportional	Causes neck flexion supine; use shoulder roll to achieve neutral position [3]
Head/Body ratio	Head is 25% of body length	Head is 12% of body length	Position differently; sniffing position not always optimal [3]
Tongue	Relatively large, fills oral cavity	Proportional	More difficult mask seal; more likely to cause obstruction [3]
Epiglottis	Omega-shaped, floppy, angled (45 degrees)	Flat, angled posteriorly	Use straight blade to lift directly; may obscure view [4]
Laryngeal position	High: C3-C4 (infant), C4-C5 (child)	C5-C6	More anterior appearance at laryngoscopy [4]
Vocal cords	Angled anteriorly (makes angle with trachea)	Perpendicular to trachea	ETT may catch on anterior commissure [4]
Narrowest point	Cricoid ring (subglottic)	Glottis (vocal cords)	Cuffed tube risk; oedema causes significant obstruction [3,4]
Trachea length	4-5 cm (infant), 5-7 cm (child)	10-12 cm	High risk of right mainstem intubation; short margin of safety [4]
Trachea diameter	3-4 mm (term newborn)	15-20 mm	1mm oedema = 75% reduction in cross-sectional area (Poiseuille's law) [24]
Cricothyroid membrane	2.6 x 3.0 mm (infant), 6.5 x 6.6 mm (8 years)	10 x 22 mm	Needle cric in young children; surgical cric difficult [25]

Poiseuille's Law - Why Paediatric Oedema Matters

Poiseuille's Law: Resistance is inversely proportional to the fourth power of the radius (R = 1/r4)

Scenario	Infant (4mm diameter)	Adult (8mm diameter)
Normal airway	Baseline resistance	Baseline resistance
1mm oedema	75% reduction in cross-sectional area; 16-fold increase in resistance	44% reduction; 3-fold increase in resistance [24]

Clinical Relevance: Minor upper airway inflammation (croup, post-extubation) causes profound airway compromise in children but minimal symptoms in adults.

Laryngoscopy View Differences

INFANT LARYNGOSCOPY VIEW:
- Use straight blade (Miller 0-1)
- Lift epiglottis directly (do not place in vallecula)
- Larynx appears more anterior
- External laryngeal manipulation (ELM) helpful
- Omega-shaped epiglottis may obscure cords

       Tongue
         │
         ▼
    ┌─────────┐
    │  Omega  │ ← Floppy epiglottis
    │ Epiglot │
    └────┬────┘
         │
    ┌────┴────┐
    │  Vocal  │ ← Angled anteriorly
    │  Cords  │
    └────┬────┘
         │
    ┌────┴────┐
    │ Cricoid │ ← NARROWEST POINT in children under 8 years
    │  Ring   │
    └─────────┘

Physiology

Oxygen Consumption and Desaturation

Parameter	Infant	Child	Adult
Oxygen consumption	6-8 mL/kg/min	5-6 mL/kg/min	3-4 mL/kg/min [5]
FRC	30 mL/kg	34 mL/kg	34 mL/kg [6]
FRC/Oxygen consumption ratio	Low	Low	High [6]
Safe apnoea time (preoxygenated)	30-90 seconds	1-3 minutes	3-8 minutes [5,6]
Time to desaturation (100% to 80%)	Under 100 seconds	100-200 seconds	Over 300 seconds [26]

Why Children Desaturate Rapidly

High oxygen consumption relative to body weight (2-3× adult)
Low functional residual capacity (oxygen reservoir)
Closing capacity exceeds FRC in infants (airway collapse during tidal breathing)
Higher respiratory rate - less time for preoxygenation
Difficulty with preoxygenation - cannot cooperate, cry causes desaturation

Implications for Airway Management

Preoxygenation is critical: 100% O2 for 3-5 minutes if cooperative; high-flow nasal oxygen during apnoea (THRIVE) if available
Rapid sequence intubation: True RSI with no bag-mask ventilation increases desaturation risk - consider modified RSI with gentle BVM
Apnoeic oxygenation: Nasal cannula at 1-5 L/min during laryngoscopy maintains oxygen delivery
Be prepared for rapid desaturation: SpO2 can fall from 100% to under 70% in under 60 seconds in an infant

Equipment Sizing

Age-Based Formulas

Clinical Pearl

Essential Equipment Sizing Formulas:

Equipment	Formula	Notes
ETT size (cuffed)	Age/4 + 3.5	Children over 2 years; have half sizes above/below [27]
ETT size (uncuffed)	Age/4 + 4	Traditionally used under 8-10 years; now less common [27]
ETT depth at lip	Age/2 + 12 cm	Alternative: ETT ID × 3 [28]
ETT depth at nose	Age/2 + 15 cm	Nasotracheal intubation [28]
Laryngoscope blade	Neonate: Miller 0; Infant: Miller 1; Child: Miller/Mac 2; Adolescent: Mac 3-4 [29]
LMA size	See weight-based table below	[30]
Suction catheter	2 × ETT size	e.g., 4.0 ETT = 8Fr suction [31]
NG/OG tube	Age/2 + 10	French gauge [31]

ETT Sizing by Age and Weight

Age	Weight (kg)	Cuffed ETT (mm ID)	Uncuffed ETT (mm ID)	Depth at Lip (cm)
Premature	Under 1	2.5	2.5-3.0	6-7
Term newborn	3-4	3.0-3.5	3.5	9-10
3-6 months	5-7	3.5	3.5-4.0	10-11
6-12 months	7-10	3.5-4.0	4.0	11-12
1-2 years	10-12	4.0	4.0-4.5	12-13
2-4 years	12-16	4.0-4.5	4.5-5.0	13-14
4-6 years	16-20	4.5-5.0	5.0-5.5	14-15
6-8 years	20-25	5.0-5.5	5.5-6.0	15-16
8-10 years	25-30	5.5-6.0	6.0-6.5	16-17
10-12 years	30-40	6.0-6.5	6.5-7.0	17-19
Over 12 years	Over 40	6.5-7.5	7.0-8.0	19-22

Cuffed vs Uncuffed ETT Debate

Factor	Cuffed ETT	Uncuffed ETT
Traditional view	Avoid under 8 years (subglottic stenosis risk)	Standard in children
Modern evidence	Safe in all ages with pressure monitoring (under 20-25 cmH2O) [32]	Still used but declining
Advantages	Better seal, less leak, fewer reintubations, more accurate ETCO2 [32]	No cuff pressure monitoring needed
Disadvantages	Requires cuff pressure monitoring; narrower lumen for equivalent OD	Air leak, multiple tube changes, aspiration risk
RCH/APLS recommendation	Cuffed tubes acceptable in all ages [19]	Have uncuffed available as backup

Current Consensus: Cuffed ETTs are acceptable in all children including infants when cuff pressure is monitored and maintained below 20-25 cmH2O [32].

LMA/Supraglottic Airway Sizing

LMA Size	Weight (kg)	Age Approximation	Max Cuff Volume (mL)
1	Under 5 kg	Neonates	4
1.5	5-10 kg	Infants	7
2	10-20 kg	1-5 years	10
2.5	20-30 kg	5-10 years	14
3	30-50 kg	10-14 years	20
4	50-70 kg	Adult small	30
5	Over 70 kg	Adult large	40

i-gel Sizing

i-gel Size	Weight (kg)
1	2-5 kg
1.5	5-12 kg
2	10-25 kg
2.5	25-35 kg
3	30-60 kg
4	50-90 kg
5	Over 90 kg

Bag-Mask Ventilation in Children

Equipment Selection

Age Group	Bag Size	Mask	Notes
Neonate/Infant	250-500 mL	Round (size 0-1)	Finger-sized round mask covers nose and mouth [33]
Child 1-8 years	500-750 mL	Round or triangular (size 2-3)	Transition to triangular mask [33]
Child over 8 years	750-1000 mL	Adult triangular (size 3-4)	Adult equipment appropriate [33]

Technique

Clinical Pearl

Optimal Bag-Mask Ventilation Technique in Children:

Position:

Infant: Neutral position or slight extension (shoulder roll to align)
Child: Sniffing position (similar to adult but less extension needed)
Avoid hyperextension (kinks the pliable trachea)

Mask Seal:

E-C technique: Thumb and index finger form "C" on mask; 3rd-5th fingers form "E" under mandible
Two-person technique: One person holds mask with two hands (bilateral jaw thrust); second squeezes bag
Cover from bridge of nose to chin crease; avoid pressure on eyes

Ventilation:

Rate: 12-20 breaths/minute (age-dependent)
Tidal volume: 6-8 mL/kg (visible chest rise)
Squeeze bag over 1 second
Observe chest rise; adjust if no rise (reposition, suction, airway adjunct)
Avoid excessive pressures (gastric insufflation, aspiration, pneumothorax)

Adjuncts if Needed:

Oropharyngeal airway (OPA): Size = corner of mouth to angle of mandible; only if unconscious
Nasopharyngeal airway (NPA): Size = nare to tragus; can use if semi-conscious
Two-person ventilation if difficult

Troubleshooting Failed BMV

Problem	Solution
Inadequate chest rise	Reposition head/neck; adjust mask seal; use two-person technique [33]
Air leak around mask	Better seal technique; try different mask size; two-hand technique [33]
High airway resistance	Insert OPA/NPA; suction; check for obstruction [33]
Gastric distension	Reduce tidal volume/pressure; insert NG tube after intubation [33]
Oxygen desaturation despite BVM	Prepare for intubation or SGA; call for help [33]

Rapid Sequence Intubation (RSI) in Children

Indications for RSI

Respiratory failure not responding to non-invasive management
Impending respiratory arrest
Severe shock requiring mechanical ventilation
Decreased consciousness (GCS 8 or less) with loss of airway protective reflexes
Status epilepticus requiring airway protection
Anticipated deterioration (epiglottitis, progressive stridor)
Major trauma requiring airway control

Pre-RSI Preparation

Checklist (SOAP-ME):

Suction: Yankauer, appropriate catheter size
Oxygen: High-flow, bag-mask connected, THRIVE if available
Airway: ETT (calculated size + 0.5 above and below), laryngoscope (2 blades), bougie, stylet
Pharmacy: Draw up drugs (sedation, paralysis, atropine, emergency drugs)
Monitoring: SpO2, ETCO2, ECG, NIBP
Equipment: LMA (backup), surgical airway kit, difficult airway trolley

Weight Estimation

Method	Formula/Technique
Measured weight	Gold standard if available
Broselow tape	Length-based; colour-coded zones
APLS formula (1-10 years)	Weight (kg) = (Age + 4) × 2
Parent/carer estimate	Often accurate; use if reliable

RSI Drug Dosing (Weight-Based)

Drug	Dose	Max Dose	Notes
Induction Agents
Propofol	2-4 mg/kg IV	200 mg	Avoid in haemodynamic instability; causes hypotension [7]
Ketamine	1-2 mg/kg IV	200 mg	Preferred if haemodynamically unstable; maintains airway reflexes; raises ICP debate resolved (safe) [7,8]
Thiopentone	3-5 mg/kg IV	500 mg	Cerebral protection; significant hypotension [7]
Midazolam	0.1-0.3 mg/kg IV	10 mg	Less haemodynamic effect; slower onset [7]
Neuromuscular Blockers
Rocuronium	1.2 mg/kg IV	100 mg	Rapid onset (60 sec at high dose); reversible with sugammadex [8]
Suxamethonium	1-2 mg/kg IV	150 mg	Fastest onset (30-60 sec); avoid if hyperkalaemia risk, burns, neuromuscular disease [8]
Adjuncts
Fentanyl	1-3 mcg/kg IV	100 mcg	Blunts sympathetic response; use with caution in hypovolaemia [7]
Atropine	20 mcg/kg IV	0.6 mg	Consider if under 1 year old or if giving suxamethonium (prevents bradycardia) [34]
Glycopyrrolate	4-10 mcg/kg IV	0.2 mg	Alternative to atropine; less CNS effects [34]

Atropine Before RSI - When to Use

Indication	Rationale
Infants under 1 year	Higher vagal tone; bradycardia with laryngoscopy [34]
Suxamethonium use (especially repeat dose)	Muscarinic effects cause bradycardia [34]
Known congenital heart disease	May not tolerate bradycardia [34]
Previous bradycardia with airway manipulation	History of vagal response

Dose: Atropine 20 mcg/kg IV (minimum 100 mcg, maximum 600 mcg) [34]

Suxamethonium Contraindications in Children

Absolute Contraindications	Relative Contraindications
Hyperkalaemia or at-risk states	Recent burns (after 24-48 hours)
Family history of malignant hyperthermia	Crush injury/trauma (after 24-48 hours)
Known muscular dystrophy	Prolonged immobilisation
Denervating conditions (spinal cord injury after 24 hours)	Upper motor neuron lesion
Severe burns greater than 24-48 hours	Chronic renal failure with hyperkalaemia
Personal history of malignant hyperthermia

Black Box Warning: Suxamethonium can cause hyperkalemia and cardiac arrest in children with undiagnosed muscular dystrophy - use rocuronium preferentially unless rapid sequence is critical and rocuronium unavailable [8].

Intubation Technique in Children

Positioning

Age	Position	Technique
Infant (under 2 years)	Neutral/slight extension	Shoulder roll under scapulae to compensate for large occiput [3]
Child (2-8 years)	Modified sniffing	Small pillow under head; less extension than adults [3]
Older child/Adolescent	Sniffing position	Similar to adult technique [3]

Laryngoscope Selection

Age	Blade Type	Size	Technique
Premature-3 months	Miller (straight)	0	Lift epiglottis directly [29]
3 months-2 years	Miller (straight)	1	Lift epiglottis directly [29]
2-6 years	Miller or Macintosh	1-2	Either technique acceptable [29]
6-12 years	Macintosh (curved)	2-3	Vallecula technique (like adults) [29]
Over 12 years	Macintosh	3-4	Adult technique [29]

Video Laryngoscopy

First-line in difficult airway: Better glottic view; standard care in many centres [35]
Learning tool: Supervising clinician can see the same view as operator
Sizing: Use appropriate paediatric blade (hyperangulated blades may make tube advancement difficult)
Caution: Improved view does not always mean easier tube passage; use stylet or bougie

ETT Confirmation

Method	Reliability	Notes
Waveform capnography	Gold standard	Must have waveform, not just colour change [36]
Colorimetric CO2 detector	Good	May be falsely negative with poor cardiac output [36]
Chest rise	Moderate	Bilateral and equal
Auscultation	Moderate	Listen axillae and epigastrium
Misting of ETT	Low	Unreliable alone
SpO2 maintained	Supportive	Late indicator
CXR	Confirmatory	ETT tip at T1-T2 (mid-trachea)

Difficult Paediatric Airway

Prediction - LEMON Adaptation for Children

Clinical Pearl

Paediatric Difficult Airway Predictors:

Factor	Specific Features
L - Look externally	Craniofacial syndromes (Pierre Robin, Treacher Collins, Goldenhar), obesity, micrognathia, midface hypoplasia
E - Evaluate	Mouth opening under 2 finger-breadths; cannot palpate landmarks
M - Mallampati	Difficult in crying/uncooperative child; limited utility under 4 years
O - Obstruction/Obesity	Epiglottitis, croup, foreign body, peritonsillar abscess, morbid obesity
N - Neck mobility	Down syndrome (atlantoaxial instability), Klippel-Feil syndrome, juvenile arthritis, cervical spine injury

High-Risk Conditions for Difficult Airway

Category	Conditions
Craniofacial syndromes	Pierre Robin, Treacher Collins, Goldenhar, Apert, Crouzon, hemifacial microsomia [37]
Chromosomal abnormalities	Down syndrome (atlantoaxial instability, macroglossia), mucopolysaccharidoses (Hunter, Hurler) [37]
Acquired conditions	Burns (facial/neck), trauma, tumours, deep space infections, angioedema [37]
Inflammatory	Epiglottitis, croup (severe), peritonsillar abscess, Ludwig angina [37]
Congenital airway	Subglottic stenosis, laryngomalacia, vascular rings, tracheomalacia [37]

Vortex Approach Adaptation for Children

The Vortex approach applies equally to children:

Face mask: Maximum 3 optimised attempts
Supraglottic airway: Maximum 3 optimised attempts
ETT: Maximum 3 optimised attempts
CICO declaration: If all three lifelines fail and cannot oxygenate

Paediatric-specific considerations:

Faster progression through algorithm (rapid desaturation)
Earlier declaration of CICO
Needle cricothyroidotomy preferred in young children [38]

Surgical Airway in Children

Needle Cricothyroidotomy

Clinical Pearl

Preferred in children under 8-10 years due to small cricothyroid membrane (CTM) dimensions.

Equipment:

Large-bore cannula: 14G (adolescent), 16-18G (child), 18-20G (infant)
Syringe with saline for aspiration
Jet ventilation system (Manujet, Sanders) OR bag-valve connected via 3-way tap
Alternatively: BVM attached to 3.0 ETT adapter inserted into cannula hub

Technique:

Identify CTM (inferior to thyroid cartilage prominence, superior to cricoid ring)
Stabilise larynx with non-dominant hand
Insert cannula at 45-degree angle caudally, aspirating until air bubbles
Advance cannula, remove needle
Confirm placement with air aspiration
Connect to jet ventilation (1 second inflation, 4-5 second expiration) OR BVM
This is a temporising measure only - proceed to definitive airway

Complications:

Posterior tracheal wall perforation
Subcutaneous emphysema
Barotrauma (especially with jet ventilation)
Inadequate ventilation
Cannula kinking/displacement

Surgical Cricothyroidotomy

Acceptable in older children/adolescents (over 8-10 years) with CTM large enough for surgical access.

Technique (Scalpel-Bougie-Tube):

Identify CTM (may be difficult in obese or short-neck children)
Stab incision through skin and CTM (single horizontal or vertical incision)
Insert bougie through membrane, caudally
Railroad size 4.0-6.0 cuffed ETT over bougie
Remove bougie, inflate cuff, confirm placement
Secure tube; prepare for formal tracheostomy

Note: In children under 8 years, CTM may be only 2.6 × 3.0 mm in infants - needle cric preferred [25].

Specific Conditions

Croup (Laryngotracheobronchitis)

Aspect	Details
Aetiology	Parainfluenza (75%), RSV, influenza, adenovirus [15]
Peak age	6 months - 3 years
Presentation	Barking cough, inspiratory stridor, hoarse voice, coryzal prodrome, worse at night
Severity grading (Westley)	Mild (stridor at rest only when agitated), Moderate (stridor at rest, mild chest retractions), Severe (stridor at rest, marked retractions, decreased air entry, altered consciousness)

Management (RCH/ANZCOR Guidelines):

Severity	Treatment	Disposition
Mild	Dexamethasone 0.15-0.6 mg/kg PO (single dose); supportive care	Discharge with safety-netting [19,39]
Moderate	Dexamethasone 0.6 mg/kg PO/IM; nebulised adrenaline (5 mL of 1:1000) if marked stridor	Observe 2-4 hours post-adrenaline; discharge if improved [19,39]
Severe	Dexamethasone 0.6 mg/kg; nebulised adrenaline 5 mL 1:1000; high-flow oxygen; ENT/PICU notification	Admit to high-dependency/PICU; repeat adrenaline PRN [19,39]
Impending respiratory failure	Intubation (use ETT 0.5-1mm smaller than calculated); consider heliox; PICU [19,39]

Red Flag

Croup Red Flags:

Stridor at rest that persists despite nebulised adrenaline
Altered conscious state
Cyanosis or SpO2 below 92%
Silent chest (pre-terminal)
Drooling (consider epiglottitis)
No response to dexamethasone/adrenaline (consider alternative diagnosis)

Epiglottitis

Aspect	Details
Aetiology	Haemophilus influenzae type b (pre-vaccine); now Streptococcus, Staphylococcus, viral [16]
Peak age	2-6 years (classical); now adults more common due to Hib vaccine
Presentation	Rapid onset (hours), high fever, toxic appearance, drooling, tripod position, muffled voice, minimal cough, NO coryzal prodrome

Key Differentiators from Croup:

Feature	Croup	Epiglottitis
Onset	Gradual (days)	Rapid (hours)
Fever	Low-grade	High (over 39 degrees)
Cough	Barking	Minimal/absent
Drooling	No	Yes
Voice	Hoarse	Muffled
Posture	Normal	Tripod/sitting forward
Appearance	Non-toxic	Toxic
Prodrome	Coryzal	Absent

Management:

Red Flag

DO NOT agitate the child with epiglottitis:

No throat examination
No blood tests
No IV cannulation
Keep parent with child
Allow position of comfort
Humidified oxygen (blow-by only)

Call for expert help: ENT, anaesthesia, PICU
Prepare for emergency airway: Theatre/resuscitation bay
Controlled intubation in theatre by most senior anaesthetist with ENT standby
Inhalational induction (sevoflurane) with spontaneous ventilation until deep
Use ETT 1-2 sizes smaller than expected
IV antibiotics after securing airway: Ceftriaxone 50 mg/kg IV (max 2g)
PICU admission for observation; extubate when air leak develops (24-48 hours)

Foreign Body Aspiration

Aspect	Details
Peak age	1-3 years (oral exploratory phase) [17]
Common objects	Peanuts, seeds, small toys, coins, hot dogs
Presentation	Witnessed choking event, sudden onset cough/wheeze, unilateral decreased air entry, stridor (if laryngeal/tracheal)

Management Algorithm (ANZCOR Guideline 4):

CONSCIOUS CHILD WITH FOREIGN BODY OBSTRUCTION:

Effective cough?
        │
    ┌───┴───┐
   YES      NO
    │        │
 Encourage  Ineffective cough / Unable to cough
  coughing   │
    │        ▼
    │   Responsive?
    │        │
    │    ┌───┴───┐
    │   YES     NO
    │    │       │
    ▼    ▼       ▼
        ┌────────────────┐
        │ INFANT (under 1yr)  │     ┌────────────────┐
        │ 5 back blows   │     │ CHILD (greater than 1yr)   │
        │ 5 chest thrusts│     │ 5 back blows   │
        │ (no abdominal) │     │ 5 chest thrusts│
        └────────────────┘     │ (or abdominal) │
                               └────────────────┘
                                       │
        If becomes unconscious:        ▼
               │                  CPR (15:2)
               ▼                  Look for FB
        Start CPR (15:2)          each time mouth
        Look for visible FB       opened before
        each cycle                ventilation

Post-retrieval/stable child with history of FB:

CXR (inspiratory/expiratory or decubitus films)
Rigid bronchoscopy if confirmed or high suspicion
Do not attempt blind finger sweeps in children

LMA and Supraglottic Airway Use in Children

Indications

Bag-mask ventilation failure as rescue device
Planned use for brief procedures
Cannot intubate, cannot oxygenate (CICO) rescue prior to FONA
Resuscitation (ARC/ANZCOR acceptable airway if intubation expertise unavailable)

Insertion Technique

Classic LMA:

Select appropriate size based on weight
Fully deflate cuff
Lubricate posterior surface
Open mouth with non-dominant hand
Insert with opening facing anteriorly
Advance along hard palate until resistance felt
Inflate cuff to just seal (minimal leak at 20 cmH2O)
Confirm with ETCO2, chest rise, SpO2

i-gel:

Select size based on weight
Lubricate posterior surface
Insert with notch facing chin
Advance until resistance felt
No cuff inflation required
Confirm placement

Troubleshooting

Problem	Solution
Air leak	Check size; reinflate cuff; reposition; try larger size
Gastric insufflation	Check position; use second-generation SGA with gastric drain
Obstruction/high pressures	Reposition; ensure tongue/epiglottis not folded; try different device
Regurgitation	Second-generation SGA with gastric port; suction via gastric channel

Needle Cricothyroidotomy in Detail

Equipment for Paediatric Needle Cricothyroidotomy

Item	Specification
Cannula	14G (over 8 years), 16-18G (1-8 years), 18-20G (under 1 year)
Syringe	5-10 mL with saline
Connection	3-way tap or Luer-lock to jet ventilator
Alternative connection	3.0 ETT adapter inserted into cannula hub, connect to BVM
Jet ventilator	Manujet, Sanders injector (if available)
Oxygen source	Wall outlet at 1-4 bar (15-60 psi)

Jet Ventilation Settings (if using)

Age	Driving Pressure	I:E Ratio
Infant	0.5-1 bar (7-15 psi)	1:4 minimum
Child	1-2 bar (15-30 psi)	1:4 minimum
Adolescent	2-4 bar (30-60 psi)	1:4 minimum

Critical: Allow full passive exhalation (4-5 seconds); risk of barotrauma if stacking breaths. This is oxygenation only, not ventilation - CO2 will rise; proceed urgently to definitive airway.

Alternative Oxygenation via Cannula

If jet ventilation unavailable:

Insert cannula as above
Remove syringe, attach 3.0 ETT adapter directly to cannula hub
Connect to paediatric BVM
Attempt gentle ventilation with long expiratory time
Watch for chest rise and subcutaneous emphysema
This provides minimal ventilation - proceed to definitive airway

Indigenous Health Considerations

Aboriginal and Torres Strait Islander Children

Important Note: Higher Burden of Respiratory Disease:

2-3× higher rates of hospitalisation for respiratory infections [22]
Higher rates of bronchiectasis requiring repeated airway interventions [22]
Higher prevalence of chronic suppurative lung disease [22]
Post-infectious bronchiectasis from pneumonia, pertussis, measles [22]

Cultural Safety in Airway Emergencies:

Family presence is important - allow family members in resuscitation if they wish
Use Aboriginal Health Workers (AHW) or liaison officers when available
Brief clear explanations to family even during emergency
Avoid jargon; use interpreter services if English not first language
Some families may prefer traditional healing alongside Western medicine - respect this
Be aware of "sorry business" (bereavement) which may affect family attendance
Document cultural considerations in medical record

Maori Children (New Zealand)

Important Note: Health Disparities:

Higher rates of bronchiolitis hospitalisation [23]
Higher rates of rheumatic fever (may affect cardiac status during RSI) [23]
Higher prevalence of obesity affecting airway management [23]

Cultural Safety:

Whanau (extended family) involvement in decision-making
Te Reo Maori interpreter if needed
Karakia (prayer) may be requested before procedures
Head is tapu (sacred) - explain necessity of airway interventions
Kaumatua (elder) may need to be consulted for major decisions

Remote and Rural Considerations

RFDS/retrieval team guidance: Telemedicine for paediatric airway emergencies
Limited equipment: May need improvisation; ensure basic sizing available
Delayed definitive care: Lower threshold for securing airway before transport
Family separation: May be significant distances from extended family for support

Pitfalls and Pearls

Clinical Pearl

Clinical Pearls:

Position matters more in children: Neutral/slight extension, shoulder roll in infants - hyperextension kinks the pliable trachea
Straight blade in infants: Lift epiglottis directly; omega-shaped epiglottis obscures view with curved blade in vallecula
Have smaller ETT ready: Subglottic stenosis is common; if there's resistance, go down 0.5mm
Cuffed tubes are safe: Modern evidence supports cuffed tubes in all ages with pressure monitoring (under 20-25 cmH2O)
Atropine in infants: Consider pretreatment to prevent vagal bradycardia
Ketamine is your friend: Maintains airway reflexes, haemodynamic stability; "dissociative dose" preserves some ventilation
Video laryngoscopy first: In anticipated difficult airway; learning tool for supervisors
External laryngeal manipulation (ELM/BURP): Improves view; have assistant apply gentle pressure

Red Flag

Pitfalls to Avoid:

Not preparing for rapid desaturation: Have suction, rescue devices, and surgical airway ready
Hyperextending infant's neck: Causes tracheal kinking; use neutral position with shoulder roll
Using adult ETT size formulas: Overestimates size; use paediatric formulas
Forgetting right mainstem intubation risk: Short trachea; advance cautiously; confirm with capnography and auscultation
Delayed declaration of CICO: Children die faster than adults; declare early
Attempting too many intubation attempts: Maximum 3 attempts per device; move to rescue strategy
Blind finger sweep for foreign body: May push object further; only remove if directly visualised
Agitating child with epiglottitis: Can precipitate complete obstruction

Viva Practice

Viva Scenario

Stem: A 2-year-old presents to the ED at 2 AM with barking cough, stridor at rest, and marked intercostal retractions. Temperature 38.2 degrees, SpO2 93% on room air, HR 145.

Opening Question: How would you assess and manage this child?

Model Answer: This child has severe croup based on stridor at rest, intercostal retractions, and hypoxia. My immediate priorities are:

Do not distress the child - allow parent to hold, position of comfort
Oxygen - high-flow blow-by or Hudson mask if tolerated
Corticosteroids - Dexamethasone 0.6 mg/kg PO/IM immediately (approximately 6-7mg for typical 2-year-old ~11kg)
Nebulised adrenaline - 5 mL of 1:1000 (5mg) via nebuliser given the severity
Notify senior ED/PICU/ENT - may need escalation
Prepare for potential intubation - have equipment ready but expectant management first

Follow-up Questions:

What are the red flags suggesting impending respiratory failure?
- Model answer: Altered consciousness (listlessness or agitation), cyanosis, decreasing respiratory effort ("tiring out"), silent chest, poor air entry despite effort, SpO2 under 90% on oxygen
If you need to intubate, what size ETT would you use?
- Model answer: Calculate using formula (Age/4 + 3.5 for cuffed = 4.0mm or Age/4 + 4 for uncuffed = 4.5mm), then use 0.5-1mm smaller due to subglottic oedema. So 3.5mm cuffed or 4.0mm uncuffed. Have sizes above and below available.
When can this child be discharged?
- Model answer: After treatment, observe for 2-4 hours post-nebulised adrenaline (rebound stridor can occur). Discharge criteria: No stridor at rest, comfortable on room air, SpO2 over 94%, able to drink, reliable parents, access to medical care. Provide safety-net advice about when to return.

Discussion Points:

Steroid onset is 2-4 hours; adrenaline provides bridge
Adrenaline effect lasts 1-2 hours; rebound can occur
Heliox (70% helium/30% oxygen) reduces work of breathing in severe cases

Viva Scenario

Stem: A 4-year-old is brought in by ambulance sitting forward, drooling, with a muffled voice and high fever. The parents report rapid onset over 4 hours. Stridor is present. SpO2 is 94% on blow-by oxygen.

Opening Question: What is your differential diagnosis and initial approach?

Model Answer: The classic presentation (acute onset, drooling, tripod position, high fever, muffled voice, minimal cough) is highly suspicious for epiglottitis until proven otherwise. Differentials include severe croup (less likely - no coryzal prodrome, different voice quality), peritonsillar/retropharyngeal abscess, and bacterial tracheitis.

Immediate approach:

Do NOT examine throat or distress the child
Keep child with parents in position of comfort
Humidified oxygen by blow-by only
Immediately call: Senior ED consultant, ENT, Anaesthesia, PICU
Prepare for emergency airway in theatre - this child needs controlled intubation
Stay with the child - do not leave unattended
Do NOT attempt IV access yet - may precipitate complete obstruction

Follow-up Questions:

Where should this child be intubated and by whom?
- Model answer: In the operating theatre by the most senior available anaesthetist, with ENT surgeon scrubbed and ready for emergency surgical airway if intubation fails. Inhalational induction with sevoflurane maintaining spontaneous ventilation until sufficiently deep. IV access after induction.
What antibiotic would you prescribe?
- Model answer: Ceftriaxone 50 mg/kg IV (max 2g) once daily after airway secured. Covers H. influenzae (if unvaccinated), Streptococcus, Staphylococcus.
How do you know when to extubate?
- Model answer: Typically 24-48 hours. Signs of readiness include: development of air leak around ETT (suggesting reduced supraglottic swelling), afebrile, improved inflammatory markers. Some centres perform direct laryngoscopy to assess epiglottis. Extubate in controlled setting with capability for re-intubation.

Discussion Points:

Hib vaccine has dramatically reduced incidence, but non-typeable H. flu and other organisms now predominate
Adults are now more commonly affected than children
Mortality with optimal management is under 1%; without, up to 10%

Viva Scenario

Stem: A 5-year-old (20kg) with severe head injury (GCS 7) requires RSI. During laryngoscopy, SpO2 drops from 100% to 78% within 45 seconds. You cannot see the cords.

Opening Question: What are your immediate actions?

Model Answer: This is a failed first attempt with critical desaturation. Immediate actions:

Stop laryngoscopy - maximum 30 seconds per attempt
Bag-mask ventilate with 100% oxygen - two-person technique, jaw thrust, OPA if needed
Optimise position - ensure neutral/sniffing position with shoulder roll
Call for help - senior colleague, anaesthetics
Plan next attempt - different operator, video laryngoscopy, bougie
Once SpO2 over 95%: Attempt intubation again with optimisation

If second attempt fails:

Insert LMA (size 2 or 2.5 for 20kg child) as rescue device
Ventilate through LMA
Consider intubation through LMA or prepare for surgical airway if all attempts fail

Follow-up Questions:

What RSI drugs and doses would you have used?
- Model answer:
  - Preoxygenation with 100% O2 for 3 minutes (or apnoeic oxygenation with nasal cannula 5L/min during attempt)
  - Atropine 20 mcg/kg (400mcg) - consider in this age
  - Induction: Ketamine 1-2 mg/kg (20-40mg IV) OR Propofol 2-3 mg/kg (40-60mg) if haemodynamically stable OR Thiopentone 4 mg/kg (80mg) for neuroprotection
  - Paralysis: Rocuronium 1.2 mg/kg (24mg) for rapid onset
  - Fentanyl 1-2 mcg/kg (20-40mcg) to blunt ICP rise
What ETT size and depth would you use?
- Model answer: ETT size = Age/4 + 3.5 = 5/4 + 3.5 = 4.75, so use 4.5 or 5.0 cuffed. Depth at lip = Age/2 + 12 = 14.5 cm, so approximately 14-15 cm at lip. Alternative: ETT ID × 3 = 13.5-15 cm.
What is the maximum number of intubation attempts before declaring CICO?
- Model answer: Vortex approach allows 3 optimised attempts at each of face mask, SGA, and ETT. However, in paediatrics with rapid desaturation, move faster between modalities. If cannot oxygenate despite optimal BVM AND optimal SGA AND failed ETT attempts = CICO. In a 5-year-old, would proceed to scalpel-bougie-tube surgical cricothyroidotomy (CTM is approximately 5-6mm at this age).

Discussion Points:

THRIVE (high-flow nasal oxygen during apnoea) extends safe apnoea time
Video laryngoscopy improves first-pass success
External laryngeal manipulation (ELM/BURP) improves view
Have bougie ready for all intubations

Viva Scenario

Stem: A 14-month-old is brought in by parents who report sudden choking while eating peanuts 1 hour ago. The child had a coughing fit but is now breathing comfortably with occasional cough. Mild wheeze on right side.

Opening Question: How do you assess and manage this child?

Model Answer: This is a witnessed foreign body aspiration with asymmetric signs suggesting the foreign body has lodged distally (likely right main bronchus given anatomy).

Assessment:

Stability - if breathing comfortably, do not intervene urgently
Examination - look for stridor (proximal FB), unilateral wheeze/decreased air entry (distal FB)
Investigations - CXR (inspiratory and expiratory views or right/left decubitus views) looking for hyperinflation, atelectasis, or radio-opaque FB

Management of stable child with suspected distal FB:

Keep nil by mouth - anticipate bronchoscopy
Contact ENT/Paediatric Surgery - rigid bronchoscopy is definitive management
Avoid excessive coughing - could dislodge to more proximal position
Admit for observation if bronchoscopy delayed

Follow-up Questions:

What would you do if this child suddenly deteriorated with complete obstruction?
- Model answer:
  - Infant (under 1 year): 5 back blows, 5 chest thrusts, repeat cycle
  - Child (over 1 year): 5 back blows, 5 abdominal thrusts (Heimlich)
  - If unconscious: Start CPR (15:2), look in mouth before each ventilation for visible FB
  - If FB visible: Remove with Magill forceps under direct laryngoscopy
  - Do NOT perform blind finger sweeps
The CXR shows right-sided hyperinflation. What does this indicate?
- Model answer: Ball-valve effect - the FB allows air entry on inspiration but traps air on expiration, causing hyperinflation of the affected side. This is classic for partially obstructing endobronchial FB.
What are the risks of peanut aspiration specifically?
- Model answer: Peanuts and other food material cause chemical pneumonitis from the oils/lipids in addition to mechanical obstruction. This leads to significant inflammation, bronchospasm, and infection risk. Early removal is important.

Discussion Points:

Most FB lodge in right main bronchus (shorter, wider, more vertical)
Rigid bronchoscopy is gold standard; flexible bronchoscopy for diagnosis
Delayed presentation (weeks-months) may present with recurrent pneumonia

OSCE Scenarios

Station 1: Paediatric Bag-Mask Ventilation

Format: Skills station Time: 8 minutes Setting: Paediatric resuscitation bay

Candidate Instructions:

A 6-month-old infant is apnoeic and bradycardic after a choking episode. The foreign body has been removed. Demonstrate bag-mask ventilation on this infant manikin and talk through your technique.

Examiner Instructions: The candidate should demonstrate appropriate equipment selection, positioning, mask seal technique, and ventilation. After 2 minutes, inform the candidate that the chest is not rising despite their efforts and assess troubleshooting.

Equipment Provided:

Infant manikin
Various mask sizes (neonatal, infant, child)
Self-inflating bags (250mL, 500mL)
OPA sizes 000, 00, 0, 1
Suction

Marking Criteria:

Domain	Criterion	Marks
Preparation	Selects appropriate equipment (infant mask, 250-500mL bag)	/2
Positioning	Positions in neutral/slight extension; uses shoulder roll	/2
Technique	Demonstrates correct E-C clamp; achieves mask seal	/2
Ventilation	Delivers breaths over 1 second; observes chest rise	/2
Troubleshooting	When chest not rising: repositions, inserts OPA, uses two-person technique, considers suction	/2
Safety	Monitors for gastric distension; avoids hyperventilation	/1
Total		/11

Expected Standard:

Pass: 7 or above out of 11
Key discriminators: Correct equipment selection, appropriate positioning without hyperextension, effective troubleshooting

Station 2: Paediatric RSI Preparation

Format: Skills/Communication station Time: 11 minutes Setting: Resuscitation bay

Candidate Instructions:

A 3-year-old child (15kg) with status epilepticus and GCS 6 requires RSI for airway protection. The nursing staff have asked you to prepare the equipment and drugs. Talk through your preparation with the examiner acting as the nurse. The child is haemodynamically stable.

Examiner Instructions: Assess the candidate's systematic preparation, correct drug/equipment dosing, and communication with the nursing staff. After 7 minutes, inform the candidate that the parent is distressed and asks "Is my child going to be okay?" Assess communication.

Equipment Available:

Drug chart
Broselow tape
Airway equipment trolley
Drug labels

Marking Criteria:

Domain	Criterion	Marks
Airway equipment	Correctly sizes ETT (4.0 cuffed OR 4.5 uncuffed), confirms sizes above/below	/2
Laryngoscope	Selects appropriate blade (Miller 1-2 or Mac 2)	/1
Drugs - Induction	Correct dose (e.g., Propofol 30-45mg or Ketamine 15-30mg)	/2
Drugs - Paralysis	Correct dose (Rocuronium 18mg or Suxamethonium 15-30mg)	/2
Additional preparation	Mentions atropine, backup airway (LMA), suction, preoxygenation	/1
Communication with nurse	Clear, systematic handover; confirms understanding	/1
Communication with parent	Empathic, honest, provides reassurance without false promises	/2
Total		/11

Expected Standard:

Pass: 7 or above out of 11
Key discriminators: Correct weight-based dosing, appropriate ETT sizing, empathic parent communication

Station 3: Croup Management and Parent Counselling

Format: Communication station Time: 11 minutes Setting: ED cubicle

Candidate Instructions:

A 20-month-old with moderate croup has been treated with dexamethasone and nebulised adrenaline. The stridor has resolved and SpO2 is 98% on room air. The mother is anxious about taking the child home. Counsel the mother about discharge and safety-netting.

Actor Brief (Mother): You are anxious because this is your first child with croup. You are worried the stridor will come back at night. You live 45 minutes from the nearest hospital. If the candidate provides clear safety-net advice and seems competent, become reassured.

Marking Criteria:

Domain	Criterion	Marks
Introduction	Introduces self, confirms identity, ensures privacy	/1
Explanation of diagnosis	Explains croup in lay terms; reassures about benign course	/2
Treatment summary	Explains what was given (steroid, adrenaline) and effects	/2
Safety-netting	Clear return instructions: stridor at rest, drooling, colour change, poor feeding, worsening breathing	/2
Home management	Cool air, hydration, upright positioning; avoid cough suppressants	/1
Addresses concerns	Acknowledges anxiety, reassures appropriately, addresses distance from hospital	/2
Summarises and checks understanding	Clear summary, asks if questions	/1
Total		/11

Expected Standard:

Pass: 7 or above out of 11
Key discriminators: Clear safety-net advice, empathic acknowledgment of parental anxiety

SAQ Practice

Question 1 (8 marks)

Stem: A 9-month-old infant (8kg) requires emergency intubation for severe bronchiolitis with respiratory failure.

Question: List the equipment and drug doses you would prepare for rapid sequence intubation, with specific values.

Model Answer: Equipment (4 marks - 0.5 each):

ETT: 3.5 cuffed (or 4.0 uncuffed) - Age/4 + 3.5 = 3.75, use 3.5 cuffed (1 mark)
ETT depth at lip: 10-11 cm (Age/2 + 12 or tube × 3) (0.5 marks)
Laryngoscope: Miller 1 (straight blade) (0.5 marks)
LMA size 1.5 (backup) (0.5 marks)
Suction: 8Fr catheter (2 × ETT) (0.5 marks)
OPA size 00 or 0 (0.5 marks)
Self-inflating bag: 250-500mL with infant mask (0.5 marks)

Drugs (4 marks - 0.5 each):

Atropine: 20 mcg/kg = 160 mcg IV (consider in infants) (0.5 marks)
Ketamine: 1-2 mg/kg = 8-16 mg IV (preferred for haemodynamic stability) (1 mark)
OR Propofol: 2-3 mg/kg = 16-24 mg IV (if stable) (alternative 0.5 marks)
Rocuronium: 1.2 mg/kg = 9.6 mg IV (~10mg) (1 mark)
OR Suxamethonium: 2 mg/kg = 16 mg IV (alternative if rocuronium unavailable) (0.5 marks)
Adrenaline 1:10,000 (100mcg/mL): 80 mcg (0.8 mL) drawn up for emergency (0.5 marks)

Examiner Notes:

Accept reasonable rounding of drug doses
Must have backup equipment listed
Must mention preoxygenation strategy

Question 2 (6 marks)

Stem: You are managing a 4-year-old with severe croup who has failed to respond to two doses of nebulised adrenaline and remains stridorous at rest with SpO2 91% on high-flow oxygen.

Question: Outline your immediate management plan, including airway considerations.

Model Answer: Immediate actions (3 marks):

Escalate to senior ED/PICU/ENT immediately (0.5 marks)
Continue high-flow oxygen; consider heliox (70:30) if available (0.5 marks)
Repeat dexamethasone if not already given/underdosed (0.6 mg/kg) (0.5 marks)
Consider continuous nebulised adrenaline or IV adrenaline infusion (0.5 marks)
Prepare for intubation with all necessary equipment and personnel (0.5 marks)
Contact operating theatre and anaesthesia for controlled intubation (0.5 marks)

Airway considerations (3 marks):

Use ETT 0.5-1mm smaller than calculated due to subglottic oedema (1 mark)
Inhalational induction with sevoflurane to maintain spontaneous ventilation preferred (0.5 marks)
Most senior airway operator available should perform intubation (0.5 marks)
Have ENT available for emergency surgical airway (0.5 marks)
Post-intubation: PICU admission for sedation, ventilation, extubate when air leak develops (0.5 marks)

Examiner Notes:

Do not accept intubation without senior involvement
Must mention smaller ETT size

Question 3 (6 marks)

Stem: Describe the anatomical differences between the infant and adult airway and explain how each difference impacts airway management.

Question: List 6 key anatomical differences with their clinical implications.

Model Answer:

Anatomical Difference	Clinical Implication	Marks
Large occiput	Causes neck flexion supine; use shoulder roll for neutral position	1
Relatively large tongue	More likely to obstruct airway; difficult mask seal; pushes epiglottis posteriorly	1
Omega-shaped floppy epiglottis	Use straight blade to lift directly; curved blade may not control epiglottis	1
Anterior and cephalad larynx (C3-4 vs C5-6)	Appears more anterior at laryngoscopy; external laryngeal manipulation helpful	1
Cricoid ring is narrowest point (not glottis)	Risk of subglottic oedema; traditionally uncuffed tubes used; air leak at this level indicates correct size	1
Short trachea (4-5cm infant)	High risk of right mainstem intubation or accidental extubation; confirm position carefully	1

Examiner Notes:

Accept equivalent clinical implications
Must have both anatomical difference AND implication for full mark

Question 4 (8 marks)

Stem: A 3-year-old child is brought to the remote ED by RFDS with suspected epiglottitis. ENT and anaesthesia backup is 2 hours away by road. The child has increasing stridor and drooling.

Question: Describe your approach to managing this child's airway, including specific considerations for the remote setting.

Model Answer: Immediate stabilisation (4 marks):

Do not distress the child - allow to sit in parent's lap, position of comfort (0.5 marks)
Humidified oxygen by blow-by; do not force mask (0.5 marks)
Do NOT examine throat or attempt IV access initially (0.5 marks)
Initiate telemedicine/retrieval service consultation immediately (0.5 marks)
Prepare emergency airway equipment: ETT 1 size smaller than calculated, straight blade, surgical airway kit (0.5 marks)
Identify most senior airway operator available locally (0.5 marks)
Nebulised adrenaline may buy time but less effective than in croup (0.5 marks)
Have IV antibiotics drawn up but do not give until airway secured (0.5 marks)

Remote-specific considerations (4 marks):

Lower threshold for intubation if deterioration likely during transport (1 mark)
If intubation required: Inhalational induction with sevoflurane if available; alternatively careful IV ketamine RSI maintaining spontaneous ventilation until deep (1 mark)
Prepare for needle/surgical cricothyroidotomy if intubation fails (0.5 marks)
Brief parent clearly about risks and plan; may need consent for emergency surgical airway (0.5 marks)
Document everything; debrief staff after event (0.5 marks)
Consider cultural liaison for Aboriginal/Torres Strait Islander families (0.5 marks)

Examiner Notes:

Must mention remote-specific adaptations for full marks
Accept alternative approaches if clinically reasonable

Australian Guidelines

ARC/ANZCOR Paediatric Airway Guidelines

ANZCOR Guideline 12.1 - Basic Life Support:

Airway opening: Head tilt-chin lift (neutral in infant, sniffing in child)
Rescue breathing: 2 initial breaths then 15:2 ratio [40]

ANZCOR Guideline 12.2 - Choking:

Conscious infant: 5 back blows, 5 chest thrusts
Conscious child: 5 back blows, 5 abdominal thrusts
Unconscious: CPR with FB check before each breath [40]

ANZCOR Guideline 12.6 - Equipment:

Weight estimation: Broselow tape or APLS formulas
ETT sizing: Age/4 + 4 (uncuffed) or Age/4 + 3.5 (cuffed) [40]

RCH Melbourne Clinical Guidelines

Croup Clinical Practice Guideline [19]:

Westley croup score for severity assessment
Dexamethasone 0.6 mg/kg for all severities
Nebulised adrenaline 5mg (5mL of 1:1000) for moderate-severe
Observe 2-4 hours post-adrenaline before discharge

Paediatric RSI Guideline [19]:

Weight-based drug dosing charts
Equipment sizing by age and weight
Pre-intubation checklist
Post-intubation care bundle

Key Differences from AHA/ERC

Element	ARC/ANZCOR	AHA	ERC
Initial breaths	5 (primary respiratory cause)	2	5
Compression:ventilation (2 rescuers)	15:2	15:2	15:2
Defibrillation energy	4 J/kg	2-4 J/kg	4 J/kg
Drugs	Same	Same	Same

Remote/Rural Considerations

Pre-Hospital Paediatric Airway

RFDS retrieval team guidance: Contact early; telemedicine support for airway decisions
Lower threshold for securing airway: If deterioration anticipated during prolonged transport
Equipment availability: Ensure basic paediatric equipment stocked in remote clinics
Decision to intubate vs transfer: Balance risks of intubation in remote setting vs deterioration in transit
Family involvement: May be significant distances from extended family for support

Resource-Limited Airway Management

Resource	Alternative
Video laryngoscope not available	Direct laryngoscopy with bougie
i-gel not available	Classic LMA
ETCO2 not available	Clinical confirmation + CXR
Jet ventilator not available	BVM via ETT adapter in cannula
Paediatric ETT not available	Cut adult ETT to appropriate length

References

Guidelines

ANZCOR. Guideline 12.1 - Paediatric Basic Life Support. 2023. Available from: https://resus.org.au
ANZCOR. Guideline 12.6 - Equipment and Techniques in Paediatric Life Support. 2023. Available from: https://resus.org.au
Harless J, Ramaiah R, Bhananker SM. Pediatric airway management. Int J Crit Illn Inj Sci. 2014;4(1):65-70. PMID: 24741500
Adewale L. Anatomy and assessment of the pediatric airway. Paediatr Anaesth. 2009;19 Suppl 1:1-8. PMID: 19572839
Patel R, Lenczyk M, Hannallah RS, McGill WA. Age and the onset of desaturation in apnoeic children. Can J Anaesth. 1994;41(9):771-774. PMID: 7954990
Hardman JG, Wills JS. The development of hypoxaemia during apnoea in children: a computational modelling investigation. Br J Anaesth. 2006;97(4):564-570. PMID: 16873390

Pharmacology

Andolfatto G, Abu-Laban RB, Zed PJ, et al. Ketamine-propofol combination (ketofol) versus propofol alone for emergency department procedural sedation and analgesia: a randomized double-blind trial. Ann Emerg Med. 2012;59(6):504-512. PMID: 22401952
Neuhaus D, Schmitz A, Gerber A, Weiss M. Controlled rapid sequence induction and intubation - an analysis of 1001 children. Paediatr Anaesth. 2013;23(8):734-740. PMID: 23713861

Epidemiology

Graciano AL, Tamburro R, Thompson AE, Fiadjoe J, Nadkarni VM, Nishisaki A. Incidence and associated factors of difficult tracheal intubations in pediatric ICUs: a report from National Emergency Airway Registry for Children: NEAR4KIDS. Intensive Care Med. 2014;40(11):1659-1669. PMID: 25160031
Sanders RC Jr, Giuliano JS Jr, Sullivan JE, et al. Level of trainee and tracheal intubation outcomes. Pediatrics. 2013;131(3):e821-e828. PMID: 23439898
Long E, Sabato S, Babl FE. Endotracheal intubation in the pediatric emergency department. Paediatr Anaesth. 2014;24(12):1204-1211. PMID: 25203847
Long E, Cincotta DR, Grindlay J, et al. A quality improvement initiative to increase the safety of pediatric emergency airway management. Paediatr Anaesth. 2017;27(12):1271-1277. PMID: 28960667
Heinrich S, Birkholz T, Ihmsen H, Irouschek A, Ackermann A, Schmidt J. Incidence and predictors of difficult laryngoscopy in 11,219 pediatric anesthesia procedures. Paediatr Anaesth. 2012;22(8):729-736. PMID: 22340664
Fiadjoe JE, Nishisaki A, Jagannathan N, et al. Airway management complications in children with difficult tracheal intubation from the Pediatric Difficult Intubation (PeDI) registry: a prospective cohort analysis. Lancet Respir Med. 2016;4(1):37-48. PMID: 26705974

Specific Conditions

Bjornson CL, Johnson DW. Croup in children. CMAJ. 2013;185(15):1317-1323. PMID: 23939212
Shah RK, Roberson DW, Jones DT. Epiglottitis in the Hemophilus influenzae type B vaccine era: changing trends. Laryngoscope. 2004;114(3):557-560. PMID: 15091234
Fidkowski CW, Zheng H, Firth PG. The anesthetic considerations of tracheobronchial foreign bodies in children: a literature review of 12,979 cases. Anesth Analg. 2010;111(4):1016-1025. PMID: 20802055
Atkins DL, Everson-Stewart S, Sears GK, et al. Epidemiology and outcomes from out-of-hospital cardiac arrest in children: the Resuscitation Outcomes Consortium Epistry-Cardiac Arrest. Circulation. 2009;119(11):1484-1491. PMID: 19273724

Australian/NZ Guidelines

The Royal Children's Hospital Melbourne. Clinical Practice Guidelines. 2024. Available from: https://www.rch.org.au/clinicalguide/
PREDICT Network. Paediatric Research in Emergency Departments International Collaborative. Available from: https://www.predict.org.au
Rashid A, Bhananker S, Paix A. Flying Doctor emergency airway management in Australia. Can J Anesth. 2014;61(2):98-101. PMID: 24218191
Australian Institute of Health and Welfare. Aboriginal and Torres Strait Islander Health Performance Framework. 2020. Available from: https://www.aihw.gov.au
Craig E, Anderson P, Jackson C. The health status of children and young people in New Zealand. Ministry of Health. 2018. Available from: https://www.health.govt.nz

Anatomy and Physiology

Holm-Knudsen RJ, Rasmussen LS. Paediatric airway management: basic aspects. Acta Anaesthesiol Scand. 2009;53(1):1-9. PMID: 19128325
Navsa N, Tossel G, Boon JM. Dimensions of the neonatal cricothyroid membrane - how feasible is a surgical cricothyroidotomy? Paediatr Anaesth. 2005;15(5):402-406. PMID: 15828992
Fawzy H, Hendawy AM, Abuelnaga ME, Ewees IA. Comparison between apneic oxygen insufflation via standard nasal cannula and THRIVE during intubation in morbidly obese patients undergoing bariatric surgery. Anesth Essays Res. 2018;12(3):667-672. PMID: 30283165

Equipment Sizing

Weiss M, Dullenkopf A, Fischer JE, Keller C, Gerber AC. Prospective randomized controlled multi-centre trial of cuffed or uncuffed endotracheal tubes in small children. Br J Anaesth. 2009;103(6):867-873. PMID: 19887533
Kemper M, Dullenkopf A, Schmidt AR, et al. Optimal depth of insertion of endotracheal tubes: a systematic review and meta-analysis. Anesth Analg. 2022;134(6):1215-1224. PMID: 35286279
Frei FJ, Ummenhofer W. Difficult intubation in paediatrics. Paediatr Anaesth. 1996;6(4):251-263. PMID: 8827740
Jagannathan N, Ramsey MA, White MC, Szmuk P. An update on newer pediatric supraglottic airways with recommendations for clinical use. Paediatr Anaesth. 2015;25(4):334-345. PMID: 25559870

Techniques

Pediatric Advanced Life Support Provider Manual. American Heart Association. 2020.
Shi F, Xiao Y, Xiong W, Zhou Q, Huang X. Cuffed versus uncuffed endotracheal tubes in children: a meta-analysis. J Anesth. 2016;30(1):3-11. PMID: 26395414
Neumar RW, Otto CW, Link MS, et al. Part 8: adult advanced cardiovascular life support: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2010;122(18 Suppl 3):S729-S767. PMID: 20956224
Fleming B, McCollough M, Henderson SO. Myth: Atropine should be administered before succinylcholine for neonatal and pediatric intubation. CJEM. 2005;7(2):114-117. PMID: 17355664

Video Laryngoscopy

Lingappan K, Arnold JL, Fernandes CJ, Pammi M. Videolaryngoscopy versus direct laryngoscopy for tracheal intubation in neonates. Cochrane Database Syst Rev. 2018;6:CD009975. PMID: 29862482

Confirmation

Grmec S. Comparison of three different methods to confirm tracheal tube placement in emergency intubation. Intensive Care Med. 2002;28(6):701-704. PMID: 12107674

Difficult Airway

Sims C, von Ungern-Sternberg BS. The normal and the challenging pediatric airway. Paediatr Anaesth. 2012;22(6):521-526. PMID: 22594405
Chrimes N, Fritz P. The Vortex Approach to airway management. Available from: http://vortexapproach.org

Croup Management

Huang C, Bjornson C, Engel S, Malmberg LP, Jenner R, Johnson DW. The Australasian guidelines for the management of croup: a systematic review. Med J Aust. 2018;208(10):436-441. PMID: 29848259

ANZCOR Guidelines

Australian Resuscitation Council. ANZCOR Guidelines. 2023. Available from: https://resus.org.au

Additional Evidence

Myatra SN, Shah A, Kundra P, et al. All India Difficult Airway Association 2016 guidelines for the management of unanticipated difficult tracheal intubation in adults. Indian J Anaesth. 2016;60(12):885-898. PMID: 28003690
Apfelbaum JL, Hagberg CA, Caplan RA, et al. Practice guidelines for management of the difficult airway: an updated report by the American Society of Anesthesiologists Task Force on Management of the Difficult Airway. Anesthesiology. 2013;118(2):251-270. PMID: 23364566

Clinical board

Urgent signals

Exam focus

Linked comparisons

Editorial and exam context

Paediatric Airway Management

Quick Answer

ACEM Exam Focus

Primary Exam Relevance

Fellowship Exam Relevance

Key Points

Epidemiology

Australian/NZ Specific Data

Paediatric Airway Anatomy

Critical Anatomical Differences

Poiseuille's Law - Why Paediatric Oedema Matters

Laryngoscopy View Differences

Physiology

Oxygen Consumption and Desaturation

Why Children Desaturate Rapidly

Implications for Airway Management

Equipment Sizing

Age-Based Formulas

ETT Sizing by Age and Weight

Cuffed vs Uncuffed ETT Debate

LMA/Supraglottic Airway Sizing

i-gel Sizing

Bag-Mask Ventilation in Children

Equipment Selection

Technique

Troubleshooting Failed BMV

Rapid Sequence Intubation (RSI) in Children

Indications for RSI

Pre-RSI Preparation

Weight Estimation

RSI Drug Dosing (Weight-Based)

Atropine Before RSI - When to Use

Suxamethonium Contraindications in Children

Intubation Technique in Children

Positioning

Laryngoscope Selection

Video Laryngoscopy

ETT Confirmation

Difficult Paediatric Airway

Prediction - LEMON Adaptation for Children

High-Risk Conditions for Difficult Airway

Vortex Approach Adaptation for Children

Surgical Airway in Children

Needle Cricothyroidotomy

Surgical Cricothyroidotomy

Specific Conditions

Croup (Laryngotracheobronchitis)

Epiglottitis

Foreign Body Aspiration

LMA and Supraglottic Airway Use in Children

Indications

Insertion Technique

Troubleshooting

Needle Cricothyroidotomy in Detail

Equipment for Paediatric Needle Cricothyroidotomy

Jet Ventilation Settings (if using)

Alternative Oxygenation via Cannula

Indigenous Health Considerations

Aboriginal and Torres Strait Islander Children

Maori Children (New Zealand)

Remote and Rural Considerations

Pitfalls and Pearls

Viva Practice

OSCE Scenarios

Station 1: Paediatric Bag-Mask Ventilation

Station 2: Paediatric RSI Preparation

Station 3: Croup Management and Parent Counselling

SAQ Practice

Question 1 (8 marks)

Question 2 (6 marks)

Question 3 (6 marks)

Question 4 (8 marks)

Australian Guidelines

ARC/ANZCOR Paediatric Airway Guidelines

RCH Melbourne Clinical Guidelines