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Cyanotic Spells

Hypercyanotic or Cyanotic spell is a peadiatric emergency, which requires prompt recognition, and intervention to prevent disabling cerebro-vascular insults and to save lives. A cyanotic spell needs to be taken seriously not just because of the immediate threat but also because it indicates the need for early operation.

How to Recognize a Spell?

• Commonly seen below 2 years (peaks between 2 months to 6 months).

• Onset is usually spontaneous and unpredictable.

• Occurs more often in early morning, although can occur at anytime in the day.

• Infant cries incessantly, is irritable and often inconsolable.

• Tachypnea is prominent and a cardinal feature. Typically these infants have a pattern of deep and rapid breathing without significant subcostal recession.

• Cyanosis deepens as the spell progresses.

• Later gasping respiration and apnea ensues, which leads to limpness and ultimately anoxic seizures.

• Can last from minutes to hours.

• Auscultation reveals softening or disappearance of pulmonary ejection murmur.

• Occasional patient can have profound bradycardia.

Cardiac Lesions which Produce Spells

• Tetralogy of fallot.

• TOF with pulmonary atresia.

• Tricuspid atresia and PS.

• DORV with VSD and PS.

• D-TGA or L-TGA with VSD and PS.

• Single ventricle with PS.

• Atrioventricular septal defect with PS.

Mechanism of spells

Cyanotic spells are due to an acute decrease in pulmonary blood flow, increased right to left shunt and systemic desaturation due to various causes:• Infundibular spasm due to increased circulating catecholamines as a result of effort of feeding or crying.

• Activation of mechano-receptors in RV due to decrease in systemic venous return or that in LV due to decreases in pulmonary blood flow, leading to peripheral vasodilatation and fall in systemic vascular resistance producing increased right-left shunt and systemic
desaturation. Same mechanism can account for occasional episodes of bradycardia.(vaso-inhibitory response).

•Supraventricular tachycardia as a cause of spells in pulmonary atresia.

Management of Spells
•Check airway and start oxygen

If child is uncomfortable with mask or nasal cannula, deliver oxygen via tube whose end is held 1⁄2 - 1 inch away from nose. This corresponds to delivering 80 per cent oxygen.

• Knee – chest position.

• Sedate child with subcutaneous morphine 0.2 mg/kg/dose or i/m ketamine (3-5mg/kg/dose).

• Obtain a reliable intravenous access.

• Soda –bicarbonate 1- 2 ml/kg given as 1:1 dilution or can be diluted in 10 ml/kg of isolyte P which is given bolus as the initial resuscitating fluid.

• Correct hypovolemia (10 ml/kg fuild bolus of isolyte P or dextrose normal saline).

• Keep the child warm.

• Correct anemia by packed cell transfusion. Hemoglobin levels < 12 gm/dl merit correction through a blood transfusion in children with cyanotic spells.

• Start beta –blockade. Beta blockade is fairly safe unless a specific contraindication like bronchial asthma or ventricular dysfunction exists. It should always be given with heart rate monitoring.

Medications and Dosages

• IV metoprolol 0.1 mg/kg, given slowly over 5 minute.

• Can repeat every 5-min for a maximum of 3 doses.

• Can be followed by infusion 1-2 mcg/kg/minute.

• Monitor saturation, heart rates and BP.

• Aim to keep heart rate below 100/minute.

Other Options

•I/V esmolol: 500 mcg/kg over 1 min as loading dose, 50 mcg/kg/min for 4 minutes; if desaturation persists without a significant decrease in heart rate the loading dose will need to be repeated and the infusion rate can be increased in 50 mcg/kg/min increments until 300mcg/kgmin; this infusion should be maintained at the rate that produces the desired result.Esmolol is relatively expensive but has the advantage of being very short acting.

•I/V propranolol (0.1 mg/kg).

If desaturation persists and there is still no significant trend towards improvement despite maximum beta blockage.

•Start vasopressor infusion.

Methoxamine given i/v at dose of 0.1mg-0.2 mg/kg /dose or i/m (0.1- 0.4 mg/g/dose).Phenylepherine: 5 ug/kg as bolus and than 1-4 ug/kg/min as infusion.

• If spells are persistent, consider paralysing the child, elective intubation and ventilation and plan for surgery, which can be corrective or palliative (BT shunt).

• If convulsions occur-consider IV diazepam 0.2 mg/kg or IV midazolam 0.1-0.2 mg/kg/dose, as slow push.

Appropriate and timely management of cyanotic spells can save lives and prevent CNS insults.

After a Spell: After a spell is successfully managed, a careful neurological examination is mandatory. In case of suspicion of neurologic insult during a spell, a CT scan is to be done to assess the presence and extent of cerebral infarcts.

• Initiate maximally tolerated beta-blockade (propranolol 0.5-1.5 mg/kg/dose 8 hourly or 6 hourly). The dose can be titrated by the heart rate response. Beta blockade may help improve resting saturation and can decrease frequency of spells.

• Do a detailed segmental analysis by 2D echo for complete diagnosis.

• Plan towards early corrective or palliative operation (depending on the age and anatomy).

• Continue therapeutic (if anemic) or prophylactic iron therapy (if not anemic).

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