Tracheo-Oesophageal Fistula with Oesophageal Atresia

Oesophageal atresia is a congenital interruption of the oesophagus, most often with a fistula between the trachea and the distal oesophageal segment. It presents in the first hours of life with excessive drooling, choking and cyanosis on feeding.

It occurs in about 1 in 3000 to 4500 live births. About 85% have a blind upper pouch and a distal tracheo oesophageal fistula, about 8% have isolated atresia without fistula, about 4% have an H-type fistula without atresia, and the remainder have a proximal fistula or both fistulae.

Up to half of affected infants have associated anomalies, often as part of the VACTERL association (vertebral, anorectal, cardiac, tracheo oesophageal, renal and limb anomalies), and other syndromes (trisomy 18 and 21, CHARGE syndrome). Cardiac anomalies are the most common and the major determinant of survival.

Pathophysiology.

Failure of normal separation of the foregut into the trachea and oesophagus during the fourth to sixth weeks of gestation causes the anomaly. Saliva pools in the blind upper pouch and is aspirated, and air passes through the fistula into the stomach. Gastric acid refluxes through the fistula into the lungs.

• Antenatal: polyhydramnios and a small or absent stomach bubble on ultrasound (isolated atresia without fistula).
• Frothy oral secretions, drooling, and coughing, choking or cyanosis with the first feed.
• Respiratory distress, abdominal distension (distal fistula), and a scaphoid abdomen (pure atresia).
• Features of VACTERL: spine, anal, heart, renal and limb anomalies.

Red flags.

• Inability to pass a nasogastric tube beyond about 10 cm.
• Respiratory distress with aspiration, abdominal distension, or desaturation after ventilation (gas through the fistula).
• Associated cyanotic heart disease, right sided aortic arch, or low birth weight.

• Pass a firm, wide (10 French) orogastric tube, which meets resistance at 10 to 12 cm.
• Chest and abdominal X-ray with the tube in place: tube coiled in the upper pouch. Gas in the stomach and bowel indicates a distal fistula, and a gasless abdomen indicates pure atresia. Include the spine and look for associated anomalies.
• Echocardiography (cardiac anomalies and the side of the aortic arch), renal ultrasound, spine and anorectal examination, and limb assessment.
• Bronchoscopy at the time of surgery to identify the fistula, any proximal fistula and tracheomalacia. Contrast study is not routinely used. An H-type fistula needs contrast study or bronchoscopy.
• Genetic assessment and chromosomal microarray if dysmorphic.

Differential diagnosis. Choanal atresia, laryngeal cleft, laryngotracheo oesophageal cleft, bulbar dysfunction, oesophageal stenosis, congenital diaphragmatic hernia and aspiration pneumonia from other causes.

Preoperative.

• Nil by mouth, head up 30 to 45 degrees, a double lumen suction catheter in the upper pouch on continuous low suction, and IV fluids (10% glucose, 60 to 80 mL/kg on day 1). Avoid ventilation by mask or positive pressure if possible, since gas enters the stomach through the fistula, and if ventilated, keep pressures low and consider early surgical control of the fistula.
• If aspiration has occurred: ampicillin 50 mg/kg IV every 12 hours and gentamicin 5 mg/kg IV every 48 hours in the first week of life (later doses directed by levels). Give vitamin K 1 mg IM if not given.
• Treat respiratory distress, and transfer to a paediatric surgical centre.

Surgery.

• Ligation of the fistula and primary end-to-end oesophageal anastomosis within the first days of life, by thoracotomy or thoracoscopy, in stable infants. Staged repair with initial fistula ligation and gastrostomy for very low birth weight or unstable infants.
• Long gap atresia (no fistula, wide gap): gastrostomy, delayed primary anastomosis at 6 to 12 weeks after upper pouch stretching, or oesophageal lengthening, or oesophageal replacement (gastric pull up or colonic interposition).
• H-type fistula: division through a cervical approach.

Postoperative care and complications.

• Ventilation, analgesia (morphine 10 to 20 micrograms/kg/hour infusion) and often a transanastomotic feeding tube. Check for anastomotic leak by contrast study at about 5 to 7 days before oral feeds.
• Complications: anastomotic leak (up to 15%), stricture (30 to 50%, treated by dilatation), recurrent fistula, gastro oesophageal reflux (very common, treated with a proton pump inhibitor such as omeprazole 1 mg/kg/day, and fundoplication for severe cases), tracheomalacia, swallowing dysfunction and recurrent respiratory infection.
• Long term follow up for feeding, growth, respiratory health, eosinophilic oesophagitis and Barrett oesophagus, with surveillance endoscopy in adolescence and adulthood.

Monitoring. Respiratory status, feeding, growth and swallowing, with regular follow up through childhood.

Referral and escalation. Refer urgently to a paediatric surgical centre at birth for any infant with suspected oesophageal atresia, with an early cardiac assessment.

Special groups. Infants with severe cardiac disease or very low birth weight need staged repair. Long gap cases need specialist centres.