2024.1 Day 1 VIVA 7

Paediatric Anaesthesia

A 25kg, 5-year-old girl presents to your anaesthetic clinic for review prior to adenotonsillectomy in 2 weeks’ time. She has a history of mild asthma. She is on no regular medication. She has recently completed a course of amoxycillin for an upper respiratory tract infection. The patient’s mother says that her child is shy and is anxious about the procedure.

What features of your pre anaesthetic assessment are relevant to you proceeding with this case in Scenarioville?

1. History:

• Asthma:

  • From PAData: uses salbutamol 2–3× weekly, no oral steroids in last 12 months.

  • Well controlled → proceed with caution.

  • Ask: recent ED visits, hospitalisation, triggers.

• Recent URTI:

  • Symptoms resolved >2 weeks ago (per PAData) → safe to proceed.

  • If fever, purulence, or wet cough: defer per ANZCA PG29(A).

• OSA symptoms (per PAData):

  • Snoring, restless sleep, daytime fatigue.

  • Moderate severity → ↑ risk of postop obstruction.

  • Plan overnight observation in SCU.

2. Examination:

• Airway: Mallampati score, tonsil size (obstructive), mouth opening.

• Resp: Chest auscultation (wheeze), WOB, SpO₂ on room air.

3. Scenarioville-Specific Adjustments:

• No PICU or paeds anaesthetist → avoid borderline cases.

• SCU = only 4 monitored beds → must pre-warn staff.

• Retrieval = 2 hours → optimise everything pre-op.

4. Anxiety Management:

• Midazolam 0.3–0.5 mg/kg PO, max 20 mg (per PAData weight).

• Avoid midaz if severe OSA.

• Encourage parental presence during induction.

Would you proceed given her recent URTI?

Proceed only if symptoms have resolved ≥2 weeks, and there's no fever, purulent sputum, or active cough.

• URTI increases the risk of laryngospasm, bronchospasm, and desaturation in children under GA.

• ANZCA PG29(A) suggests delaying elective surgery in the presence of active infection.

• In Scenarioville, retrieval delay (2 hours) and lack of HDU mean avoiding even moderate risk is prudent.

• Elective case → low threshold for deferral until child is fully well.

How would you assess asthma severity?

Use a combination of:

• Daytime symptoms,

• Nocturnal symptoms,

• Frequency of reliever use,

• Exercise limitation,

• Recent hospital/ED visits,

• Steroid bursts in past 12 months.

Justification:

• Asthma control is a major predictor of perioperative bronchospasm.

• Objective indicators (salbutamol frequency, steroid use) help stratify risk.

• From PAData: salbutamol use 2–3x/week, no oral steroids → likely well controlled.

• Uncontrolled asthma in Scenarioville = high risk due to no PICU/ventilator backup.

What if she has OSA? How does this change your plan?

• Avoid opioids → increased sensitivity to respiratory depression.

• Plan for overnight monitoring in SCU.

• Extubate awake, monitor closely for airway obstruction.

• Discuss with parents pre-op that discharge may be delayed.

Justification:

• OSA increases risk of post-op airway obstruction, especially in REM sleep.

• Opioids blunt arousal response to hypoxia → higher risk of apnoea, bradycardia.

• Scenarioville has SCU beds but no HDU/ICU, so careful triage and overnight monitoring required for even moderate OSA.

What premedication would you prescribe, and why?

• Oral midazolam 0.3–0.5 mg/kg if no significant OSA.

• Avoid in known severe OSA.

• Parental presence at induction as an adjunct.

Justification:

• Midazolam is effective for pre-op anxiety, facilitates smoother induction.

• In OSA, even low-dose benzodiazepines can cause respiratory depression or upper airway collapse.

• Scenarioville: safety net (ICU backup) is limited → cautious approach preferred.

• Alternative anxiolysis (distraction, parental presence) carries no physiological risk.

How does Scenarioville’s lack of HDU affect your decision?

Avoid high-risk airways, active asthma, or children with severe OSA.

• Only proceed if confident post-op management can be achieved locally.

Justification:

• Retrieval takes 2 hours → delayed management of airway crises can be fatal.

• If a complication requires advanced support (e.g., BiPAP, prolonged intubation), Scenarioville lacks capacity.

• Triage cases accordingly: "safety to proceed" = ability to manage all likely complications locally.

The surgeon notes a halved tidal volume during tonsillectomy. What do you do?

1. Immediate Assessment:

• Check ETCO₂, SpO₂, chest rise, airway pressure.

• Confirm ETT position (mark, bilateral air entry).

2. Differential Dx:

• Surgical gag compression: Most common.

• ETT kinked/dislodged, bronchospasm, secretions, laryngospasm, pneumothorax.

3. Intervention:

• Ask surgeon to release gag → reassess ventilation.

• Suction ETT; auscultate.

• Bronchodilator (e.g., salbutamol via MDI/spacer or inline neb) if wheeze.

4. Airway Prep (from PAData, age 5):

• ETT: 5.0 uncuffed (age/4 + 4), Miller 1, LMA size 2, oral airway size 2.

• Suction, mask, backup ETTs, difficult airway plan ready.

5. Scenarioville Adjustments:

• No BIS → use HR/BP/ETCO₂ to guide depth.

• No ROTEM or platelets → manage bleeding clinically, consider FFP/cryo if ongoing.

• 2-hour retrieval → early escalation if deterioration persists.

How would you distinguish gag compression from bronchospasm?

• Gag compression: sudden tidal volume drop, no wheeze, improves with gag removal.

• Bronchospasm: ↑ airway pressures, expiratory wheeze, slow capnograph upstroke.

Justification:

• Common cause of intraop ventilation issues during tonsillectomy is gag malposition.

• Differentiating the two avoids inappropriate bronchodilator use or panic.

• ETCO₂ waveform is a powerful clue → bronchospasm = sloping phase 3.

• Palpating bag compliance and auscultation confirm findings.

What paediatric airway equipment would you prepare?

• ETT: 5.0 uncuffed (age/4 + 4), Miller 1 blade, size 2 LMA, oral airway size 2.

• Yankauer suction, mask, bag-valve device, lubricant, Magill forceps.

Justification:

• Precise sizing reduces risk of leak or trauma.

• Paediatric airway = narrowest at cricoid → uncuffed ETT traditionally preferred, though cuffed can be used if pressure monitored.

• Always have adjacent sizes available.

• Suction ready to avoid blood aspiration.

How would you dose fentanyl for analgesia?

• 1–2 mcg/kg IV, ideally at induction.

• Avoid intra-op boluses in known OSA.

• Consider paracetamol + NSAID as primary agents.

Justification:

• OSA patients more sensitive to opioid respiratory effects.

• Anaesthetic synergy reduces need for opioids.

• Multimodal analgesia reduces reliance on high-risk drugs.

What if bleeding occurs? How would you manage in Scenarioville?

• Call for help. Secure airway, large-bore IV x2.

• Replace with PRBCs if ongoing blood loss.

• Use FFP empirically for coagulopathy.

• Scenarioville has no platelets, no ROTEM → manage empirically.

Justification:

• Post-tonsillectomy bleeding can be rapid, life-threatening.

• Early airway control = priority.

• ROTEM/platelet support not available → need to be proactive with clinical signs (persistent ooze, clotting time).

Would you extubate deep or awake?

• Awake extubation preferred.

• Ensure full reversal of NMB, good respiratory drive, no airway secretions.

Justification:

• Deep extubation may reduce cough/laryngospasm risk, but unsafe in Scenarioville due to limited rescue capacity.

• Awake extubation allows for rapid recognition and response to obstruction or hypoxia.

How would you manage post-op pain and discharge planning in Scenarioville?

1. Analgesia:

• Paracetamol 15 mg/kg Q6h + Ibuprofen 5–10 mg/kg Q8h.

• Avoid codeine/tramadol – unpredictable metabolism.

• Oxycodone 0.1 mg/kg only as rescue if severe pain and no OSA.

2. Monitoring/Disposition:

• SCU overnight if:

  • OSA (confirmed or suspected),

  • large blood loss,

  • airway events.

• No 24h paeds cover → discharge early in day.

3. Discharge Criteria:

• Tolerating oral fluids, minimal pain on oral meds, no active bleeding.

• SpO₂ >94% on air, ambulating, cooperative parents.

4. Parental Instructions:

• Red flags: frequent swallowing, pallor, vomiting blood, SOB.

• Avoid red drinks, use soft foods, stay close to hospital.

• Emergency contact card provided.

What are your red flags for post-tonsillectomy bleeding?

• Frequent swallowing, tachycardia, pallor, vomiting blood, restlessness, hypotension.

Justification:

• In children, swallowing blood may be the only early sign.

• Tachycardia often precedes hypotension.

• Vomiting = active blood in stomach.

• Early identification allows timely intervention in a resource-limited setting.

How would you adjust analgesia if she has OSA?

• Avoid opioids.

• Maximise paracetamol + NSAID coverage.

• Consider dexamethasone intraop (antiemetic + analgesic).

Justification:

• OSA patients have reduced ventilatory response to CO₂.

• Even low-dose opioids can cause apnoea.

• NSAIDs effective with low respiratory risk.

What if she vomits post-op? Would you discharge her?

• No.

• Assess for active bleeding, opioid reaction, dehydration.

• Observe minimum 4 more hours, re-tolerate fluids before discharge.

Justification:

• Vomiting can mask or be a symptom of bleeding, especially if bright red.

• Safe discharge = no emesis + tolerating oral fluids.

• Vomiting in the setting of limited after-hours care → higher threshold for discharge.

How would you counsel her parents about home care?

• Red flags: swallowing blood, vomiting blood, SOB, lethargy.

• Encourage soft, cool foods; avoid straws/red liquids.

• Keep hydration up.

• Return to ED with any concerns.

Justification:

• Parents are first line of detection at home.

• Clear, simple instructions with examples aid recognition.

• Discharge only if they demonstrate understanding.

Would you keep her overnight in Scenarioville?

• Yes — due to OSA symptoms and post-op airway risk.

• Admit to SCU with cardiac/resp monitoring.

• Avoid sending home late in the day.

Justification:

• Most tonsillar bleeds and airway obstructions occur within 6–12 hours post-op.

• Scenarioville: no after-hours paeds, long retrieval delays.

• Overnight observation provides critical safety net.

Key Phrases:

• "With resolved URTI and well-controlled asthma, I would proceed."

• "This is likely gag compression; ask surgeon to release and reassess."

• "Given her OSA and limited local resources, I’d admit her to SCU overnight."

• "Parental education is vital; red flags include frequent swallowing and vomiting blood."