Reflex anoxic attacks (RAA) are paroxysmal, self-limited episodes of transient asystole caused by vagally mediated cardiac inhibition. They are usually brief (<30 seconds), triggered by pain, fear, or minor trauma, and most common in children aged 6 months to 2 years. Although dramatic, they are benign and self-resolving, with most children outgrowing them by school age.

🧠 Introduction

RAA are benign syncopal episodes due to exaggerated vagal reflex → transient cardiac asystole.
Typically triggered by pain, fear, anxiety, or minor head bumps.
Characterised by sudden pallor, collapse, stiffening, and sometimes clonic movements.
Often mistaken for epilepsy, but RAA have distinct features and excellent prognosis ✅.

📌 Clinical Features

Duration: Usually <15–20 seconds, rarely up to 1–2 minutes.
Typical sequence:
- Trigger (pain/fear/trauma) → sudden cardiac pause → loss of consciousness.
- Skin turns deathly pale 😨, child collapses.
- Transient rigidity or hypotonia, occasional clonic jerks.
- Rapid recovery within seconds; no confusion afterwards.
Age group: Peak between 6 months and 2 years; uncommon after 4–5 years.
Prevalence: ~0.8% of preschool-aged children.

⚖️ Differentiation from Epilepsy

RAA can mimic epileptic seizures, but important differences help avoid misdiagnosis:

Feature	Reflex Anoxic Attack	Epileptic Seizure
Trigger	Always identifiable (pain, fright, bump)	Usually none
Colour change	Marked pallor (white)	Cyanosis more common
Duration	Brief (10–20 sec, max 1–2 min)	Usually longer (1–2 min)
Postictal phase	Absent – rapid recovery	Present – confusion, sleepiness
Tongue-biting / Incontinence	Absent	May be present
EEG	Normal	Epileptiform discharges

🧪 Investigations

Usually a clinical diagnosis.
ECG: Recommended at least once to rule out cardiac arrhythmias (e.g., long QT, heart block).
Ferritin: Check iron status – iron deficiency may exacerbate attacks.
Specialist referral: For atypical cases, combined EEG + ECG monitoring during vagal stimulation may be used.

💊 Management

Reassurance: The cornerstone of management. Parents should be educated on the benign nature.
Iron supplementation: If iron deficiency is found (ferritin <50 µg/L).
Medication: Rarely needed. Atropine has been trialled in frequent, severe cases.
Pacemaker: Considered only in exceptional cases with very frequent/prolonged asystolic episodes.

👨‍👩‍👧 Parental Advice

Use the term “white breath-holding spells” rather than “seizures” to avoid unnecessary anxiety.
Explain that attacks look frightening but are not harmful and cause no brain damage.
Most children grow out of them by age 4–5. Episodes may recur in siblings.
Encourage parents to observe and time attacks, and seek review if prolonged (>3 min), frequent, or associated with injury.

✅ Key Takeaway

Reflex anoxic attacks are benign vagally mediated syncope episodes in toddlers, often misdiagnosed as epilepsy. Recognising the triggers, pallor, brevity, and rapid recovery is key. Management is reassurance, iron if deficient, and rarely pacing. Early education prevents unnecessary treatment and anxiety.

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Reflex anoxic attacks in Children