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Oesophageal atresia (OA) encompasses a group of congenital anomalies with an interruption in the continuity of the oesophagus, with or without persistent communication with the trachea. In 86% of cases there is a distal tracheooesophageal fistula, in 7% of cases there is no fistulous connection, while in 4% of cases there is a tracheooesophageal fistula without atresia. The remaining cases are made up of patients with OA with proximal, or both proximal and distal, tracheooesophageal fistula. OA occurs in 1 in 2500 live births. Infants with OA are unable to swallow saliva and are noted to have excessive salivation requiring repeated suctioning. Associated anomalies occur in 50% of cases, the majority involving one or more of the VACTERL association anomalies (vertebral, anorectal, cardiac, tracheooesophageal, renal and limb defects). The aetiology is largely unknown and is likely to be multifactorial, however, various clues have been uncovered in animal models, particularly defects in the expression of the Sonic hedgehog (Shh) gene. The vast majority of cases are sporadic and the recurrence risk for siblings is 1%. The diagnosis may be suspected prenatally by a small or absent stomach bubble on ultrasound scan at around 18 weeks of gestation. The likelihood of an atresia is increased by the presence of polyhydramnios. Inserting a nasogastric tube at birth allows the diagnosis to be confirmed or excluded and should be performed in all infants born to a mother with polyhydramnios, as well as in infants who produce excessive mucus soon after delivery. In OA, the tube will not progress beyond 10 cm from the mouth. Further confirmation is obtained by plain X-ray of the chest and abdomen. Definitive management involves disconnection of the tracheooesophageal fistula, closure of the tracheal defect and primary anastomosis of the oesophagus. Delayed primary repair should be attempted when there is a "long gap" between the ends of the oesophagus. Only very rarely will oesophageal replacement be required. Survival is directly related to birth weight and to the presence of a major cardiac defect. Infants weighing over 1500 g and having no major cardiac problems have a near 100% survival rate, but the survival rate decreases in the presence of additional risk factors. |