Paediatrics: management of Cyanosis
Bedside diagnosis of methaemoglobinaemia: place a drop of blood on a piece of filter paper.
- FBC with differential.
- Blood cultures.
- 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.
- 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.
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.
Characteristic findings include:
- Superior left axis: tricuspid atresia; endocardial cushion defect; primatial septal defect.
- Left axis deviation: pulmonary atresia ± atrial atresia.
- Marked right atrial hypertrophy: Ebstein’s anomaly.
Assessment of specific cardiac lesions.
Standard cardiorespiratory monitoring.
Therapies for specific cardiac, respiratory, and poisoning conditions are discussed elsewhere