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Cyanotic episodes spells

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    Cyanotic spells occur in children with cyanotic congenital heart disease, in particular tetralogy of Fallot and pulmonary atresia. They usually occur early in the morning, or in the context of stress or dehydration ie periods of increased oxygen demand/ultilisation. The pathophysiology is not fully understood, but relates to decreased pulmonary blood flow.

    Most episodes are self limiting.


    • Severe cyanosis/pallor (more than usual)
    • Distress/hyperpnoea (not tachypnoea)
    • Signs of dehydration
    • Lethargy/depressed conscious state
    • Known or evidence suggesting structural heart disease
    • Lessening or absence of previously heard heart murmur
    • Previous history of squatting



    • Knee to chest position
    • High flow oxygen via mask or headbox
    • Avoid exacerbating distress
    • Morphine 0.2 mg/kg IM
    • Continuous ECG and oxygen saturation monitoring, frequent BP
    • Correct any underlying cause/secondary problems, which may exacerbate episode, eg cardiac arrhythmia, hypothermia, hypoglycaemia

    If prolonged

    • Consult paediatrician or cardiologist
    • Intravenous fluids - 10 mL/kg bolus followed by maintenance fluids
    • Sodium bicarbonate 2-3 mmol/kg IV (ensure adequate ventilation)
    • Consider admission