Paediatrics: management of Cyanosis

Cyanosis: management

Investigations

Blood tests

·  FBC with differential.

·  Blood cultures.

·  Glucose.

·  Bedside diagnosis of methaemoglobinaemia: place a drop of blood on a piece of filter paper. After 30s exposure to air, normal blood turns red, while blood taken from a patient with methaemoglobinaemia remains chocolate brown.

Infection

·  Lumbar puncture as indicated.

·  Urinary culture.

Arterial blood gas

In the older child a single measurement is needed. In the neonate, assess the change in PaO₂ in response to FiO₂ 100% for 5–10min.

Chest X-ray

In the neonate the lung fields should be assessed for signs of increased vascularity, pulmonary congestion, or oligaemia. Characteristic radiographic findings are:

·  Egg on a string: transposition of the great arteries.

·  Boot-shaped heart: tetralogy of Fallot, pulmonary atresia, ventriculoseptal defect.

·  Snowman sign: supracardiac total anomalous pulmonary venous drainage.

·  Wall-to-wall heart: Ebstein’s anomaly.

Electrocardiogram

Characteristic findings include:

·  Superior left axis: tricuspid atresia; endocardial cushion defect; primum atrial septal defect.

·  Left axis deviation: pulmonary atresia ± atrial atresia.

·  Marked right atrial hypertrophy: Ebstein’s anomaly.

Echocardiography

Assessment for specific cardiac lesions.

Monitoring

Standard cardiorespiratory monitoring.

Therapy

Therapies for specific cardiac, respiratory, and poisoning conditions are discussed elsewhere