Tetralogy of Fallot Overview

Tetralogy of Fallot

• Acute cyanosis and hypoxia: Caused by infundibular spasm, which increases right-to-left shunting through the ventricular septal defect, reducing pulmonary blood flow and increasing cyanosis.

Hypercyanotic Spells ('Tet Spells')

• Triggers: Infundibular spasm, dehydration, fever, or crying, which increase right-to-left shunting, reducing pulmonary blood flow and increasing cyanosis.
• Symptoms: Sudden onset of deep blue discoloration, irritability, and increased respiratory rate.

Squatting in Children with Tetralogy of Fallot

• Purpose: To increase systemic vascular resistance, which reduces right-to-left shunting and increases pulmonary blood flow, thereby decreasing cyanosis.

Definitive Surgical Intervention

• Timing: Usually performed during the first year of life.
• Procedure: Total correction of Tetralogy of Fallot, which involves closing the ventricular septal defect and relieving right ventricular outflow tract obstruction.

Characteristics of Increasing Cyanosis

• Clubbing: Often observed in children with increasing cyanosis due to Tetralogy of Fallot, as a result of chronic hypoxia.