2024.2 Day 1 VIVA 12

Paediatric Anaesthesia

You are called to the emergency department (ED) to assist with a 5-year-old child (20 kg) who has presented with difficulty breathing and a fever of 38.8 degrees Celsius.

When you arrive, the child is sitting up, leaning forward, and is tachypnoeic.

Outline your inital assessment and management.

DRSABCDE approach:

• Danger: Ensure scene safety (e.g., infectious precautions).

• Response: Assess AVPU; child is alert but distressed.

• Airway: Listen for stridor (croup), wheeze (asthma), or gurgling (epiglottitis).

• Breathing:

  • Work of breathing (tripoding, tracheal tug, subcostal recession).

  • SpO₂ on room air (target >92%); provide high-flow O₂ if <94%.

  • Auscultate for asymmetry (foreign body) or wheeze (asthma/bronchiolitis).

• Circulation:

  • Tachycardia (compensatory vs. septic shock); capillary refill >2 sec suggests dehydration.

  • IV access (22G cannula); IO if delayed (e.g., EZ-IO in left proximal tibia).

• Disability: GCS, pupil reactivity (meningitis concern if photophobia/neck stiffness).

• Exposure: Fever source (rash? Tonsillar exudate?); keep warm to avoid shivering.

Immediate interventions:

• Croup: Nebulised adrenaline (1:1000, 5 mL) if stridor at rest.

• Asthma: Salbutamol 2.5 mg neb + ipratropium 250 mcg neb.

• Sepsis: IV ceftriaxone 50 mg/kg if petechiae/meningism.

Scenarioville constraints:

• No paediatric ICU; prepare for early retrieval if intubation likely.

• Limited blood products (FFP/cryo only; no platelets).

How would you differentiate croup from epiglottitis clinically?

Croup:

• Gradual onset over days, often preceded by coryza.

• Barking, seal-like cough.

• Stridor more pronounced when upset or crying.

• Low-grade fever, child often well-appearing.

• Typically 6 months to 6 years of age.

Epiglottitis:

• Sudden onset with rapid deterioration.

• Muffled, “hot potato” voice; painful swallowing.

• Drooling due to odynophagia.

• High fever; appears toxic and anxious, often in tripod position.

• Avoid examining throat if suspected to prevent laryngospasm.

What if the child deteriorates during assessment?

Call for senior assistance:

• Notify second RGA or senior ED/anaesthetics support early.

• Escalate to retrieval service for potential critical transfer.

Prepare for airway intervention:

• Assemble airway team, airway trolley, and paediatric drug doses.

• High-flow oxygen, BVM ventilation readiness.

• Consider early intubation if signs of impending respiratory failure (fatigue, cyanosis, decreasing GCS).

Crisis resource management:

• Allocate clear roles (airway lead, drug preparation, scribe).

• Anticipate deterioration with pre-drawn drugs and pre-oxygenation

Would you give steroids? If so, which and why?

Yes – indicated in upper airway inflammation (e.g., croup):

• Dexamethasone 0.15–0.6 mg/kg PO/IV (long-acting, anti-inflammatory).

• Evidence supports reduced need for nebulised adrenaline and reduced admission rates.

• Oral preferred if able to swallow; IV if vomiting or critically unwell.

Alternate: Nebulised budesonide 2 mg if unable to tolerate oral/IV dexamethasone.

Avoid routine use in bronchiolitis unless comorbid wheeze/asthma.

How does Scenarioville’s lack of ICU affect your decisions?

• Lower threshold for intubation to secure airway in case of deterioration.

• Aim for controlled, pre-planned intubation with full team support.

• Local resource adaptation:

  • Consider transfer post-stabilisation, even if improving, as deterioration may outpace local capability.

What monitoring would you prioritise?

Continuous monitoring:

• SpO₂: Target >94%, identify desaturation early.

• ECG: Detect arrhythmias, especially in septic or hypoxic child.

• NIBP q2–5 min: Trend MAP and perfusion; hypotension in paeds is a late sign.

• Temperature: To track fever and detect hypothermia from exposure.

Intermittent:

• ETCO₂: If intubated or BVM use; assess ventilation adequacy.

• GCS/AVPU reassessment: Neurological monitoring for decline

The child requires intubation. Describe your preparation and induction technique.

Preparation:

• Team: Second RGA for backup, experienced nurse for drug checks.

• Airway cart:

  • Cuffed ETT size 5.0 (age/4 + 4), size 4.0 and 6.0 available.

  • Videolaryngoscope (C-MAC) + Miller 1 blade as backup.

  • Size 2 LMA, bougie, and difficult airway trolley.

• Drugs:

  • Ketamine 1–2 mg/kg IV (preserves airway reflexes, bronchodilation).

  • Rocuronium 1.2 mg/kg IV (avoid succinylcholine with fever/rhabdo risk).

  • Atropine 20 mcg/kg IV to prevent bradycardia.

  • Epinephrine 1 mcg/kg IV prepared for laryngospasm/bronchospasm.

Induction choice:

• IV preferred (rapid control; avoid inhalational agitation in partial obstruction).

• Modified RSI: Gentle bag-mask ventilation with cricoid pressure (10 N).

Scenarioville adaptations:

• No fibreoptic scope; consider "awake" ketamine-assisted intubation if minimal sedation needed.

Why avoid propofol in this case?

Haemodynamic risk:

• Propofol causes vasodilation and myocardial depression.

• In a dehydrated or septic child, this can lead to profound hypotension and bradycardia.

Airway protection:

• Propofol may reduce upper airway tone and suppress reflexes – undesirable in partial obstruction.

Ketamine preferred:

• Preserves sympathetic tone, supports BP, provides bronchodilation, and maintains respiratory drive if dosed carefully.

How would you adjust dosing if the child were obese?

Weight-based strategy:

• Ketamine: Dose based on total body weight to ensure adequate anaesthesia.

• Rocuronium: Dose using ideal body weight to avoid prolonged neuromuscular blockade.

Airway consideration:

• Obesity increases risk of difficult mask ventilation and intubation – preoxygenate effectively and consider ramped positioning.

Drug onset/offset:

• Anticipate delayed clearance and prolonged sedation with lipophilic agents like ketamine in severe obesity.

What if you cannot intubate or ventilate?

Follow failed airway algorithm:

• Attempt LMA as immediate rescue – size 2 for 5-year-old.

• If unsuccessful:

  • Call for senior help and prepare for front-of-neck access.

Emergency surgical airway:

• Scalpel-bougie technique:

  • Vertical skin incision at cricothyroid membrane.

  • Horizontal stab incision through membrane, bougie insertion followed by size 4.0 ETT.

• 14G needle cricothyroidotomy if surgical unavailable – connect to oxygen for jet insufflation.

Continue oxygenation efforts between attempts; avoid repeated trauma.

Would you use cricoid pressure? What are its limitations?

Modified RSI:

• Apply cricoid pressure (10 N pre-LOC, 30 N post-LOC) to reduce aspiration risk.

Limitations:

• Can worsen laryngoscopic view; if so, release immediately.

• Controversial efficacy – may not prevent aspiration in children due to anatomy.

Best practice:

• Use only if trained personnel available; coordinate timing with intubation attempt

How would you position the child?

Optimal position:

• Sniffing position for age >2 years: Head elevated with towel under occiput.

• Use ramped positioning to align external auditory meatus with sternal notch.

If suspected epiglottitis:

• Avoid supine positioning – keep child upright with parent present.

• Proceed with gentle, ketamine-assisted intubation in OR/theatre environment if possible.

Benefit:

• Enhances FRC, improves preoxygenation, facilitates direct laryngoscopy.

Outline your fluid management plan and retrieval handover.

Fluid resuscitation:

• Deficit replacement:

  • NPO duration: If 8 hours, deficit = 8 × maintenance (4-2-1 rule: 60 mL/hr for 20 kg).

  • Replace 50% over 1st hour (240 mL 0.9% saline), then remainder over 2–4 hours.

• Maintenance: 60 mL/hr (4 mL/kg/hr for first 10 kg, 2 mL/kg/hr for next 10 kg).

• Septic shock: 20 mL/kg bolus; reassess after each (crackles/hepatomegaly = fluid overload).

Retrieval handover (ISBAR):

• Identify: "5-year-old, 20 kg, intubated for croup/sepsis."

• Situation: "Post-nebulised adrenaline, ketamine/rocuronium RSI, currently stable on SIMV."

• Background: "Fever 38.8°C, no meningism, petechiae absent."

• Assessment: "Presumed viral croup vs. bacterial tracheitis; no pneumothorax on CXR."

• Recommendation: "Urgent retrieval for PICU; currently on ceftriaxone 1 g IV.

How would you adjust fluids if the child had wheeze and crackles?

Signs of pulmonary oedema:

• Restrict to 50–60% of maintenance fluids to reduce risk of worsening overload.

• Avoid boluses unless hypotensive with signs of poor perfusion.

Diuretics:

• Furosemide 0.5–1 mg/kg IV if fluid overload evident (crackles, hepatomegaly, rising oxygen requirement).

Monitor:

• Serial lung auscultation, SpO₂, fluid balance chart, and chest X-ray if deteriorating.

• Daily weight if hospitalised >24 hours.

What bloods would you send pre-retrieval?

Full panel to guide further management and anticipate complications:

• FBC: Anaemia, leukocytosis, thrombocytopenia.

• UEC: Assess hydration, electrolyte disturbances.

• VBG with lactate: Acid-base status, perfusion marker.

• CRP/ESR: Inflammatory markers; help support diagnosis.

• Blood cultures: Before antibiotics if feasible.

• Group and hold: In case transfusion needed, especially with sepsis or DIC risk.

What if retrieval is delayed? How would you ventilate?

Mechanical ventilation:

• Pressure control mode (PCV) preferred in paediatrics.

• Tidal volume 6 mL/kg (120 mL for 20 kg child).

• PEEP 5 cmH₂O; adjust based on oxygenation and auscultation.

• Respiratory rate 20–25 breaths/min; adjust to maintain normocapnia.

Monitoring:

• ETCO₂, SpO₂, dynamic compliance, and serial ABGs if prolonged ventilation.

• Sedation with midazolam and morphine infusions if retrieval >2 hours.

Backup plans:

• Have additional oxygen cylinders and battery power ready for retrieval.

Would you give stress-dose steroids?

Indications:

• Known adrenal insufficiency (e.g., Addison’s, chronic steroid use).

• Hypotension refractory to fluids and inotropes.

Drug and dose:

• Hydrocortisone 2 mg/kg IV (max 100 mg), repeat 6-hourly if required.

Cautions:

• Not routine in sepsis unless adrenal suppression suspected.

• Avoid unnecessary steroids unless definite indication

What are your extubation criteria if improving?

Clinical stability:

• Awake, responsive, protective cough/gag reflexes intact.

• Minimal work of breathing, no accessory muscle use.

Ventilation/oxygenation:

• FiO₂ ≤0.4 with SpO₂ >94%.

• Normal or improving ETCO₂, minimal secretions.

• Airway patency:

  • Leak test positive around ETT (suggests reduced airway oedema).

  • No stridor or upper airway obstruction signs during cuff deflation.

Logistics:

• Only extubate in a centre with PICU support unless retrieval imminent.

• Ensure airway rescue equipment ready in case of re-intubation.

Key Learning Points

1. Always maintain a high index of suspicion for life-threatening upper airway obstruction in children presenting with stridor, especially with drooling, muffled voice, or rapid deterioration.

2. Ketamine is the induction agent of choice in children with potential airway obstruction, due to its bronchodilatory effects and preservation of airway tone and haemodynamics.

3. Early escalation and team activation are critical in rural or resource-limited settings, particularly when ICU or paediatric anaesthesia is not available.

4. A structured, stepwise airway plan with pre-labelled drug doses and backup strategies (LMA, surgical airway) reduces cognitive load and improves outcomes in difficult paediatric airways.

5. Fluid management must be cautious and tailored to signs of perfusion and respiratory status, with maintenance adjustments or diuretics as needed in children showing signs of overload.

Key Phrases to Use in the Viva

1. "This child has a potentially rapidly evolving airway obstruction — I will maintain them in an upright position and minimise distress."

2. "I will prepare for a ketamine-assisted intubation with full airway team support and a clear failed airway plan."

3. "In a setting without PICU or paediatric ENT backup, I have a low threshold to involve retrieval and secure the airway early."

4. "If I cannot intubate or ventilate, I will proceed to a scalpel-bougie front-of-neck access using the cricothyroid membrane landmarks."

5. "My fluid plan is 80% maintenance with boluses only if signs of shock are present — I’ll closely monitor for fluid overload."