Tracheoesophageal fistula is considered to be one of the foremost causes of severe and fatal pulmonary complications. Read on to find out more about the causes, symptoms, diagnosis, and treatment approaches of this disorder.
Tracheoesophageal fistula Definition
This is a common congenital anomaly in which the trachea and the esophagus are abnormally connected. This abnormal duct or passage is usually called fistula. It is normally abbreviated as TEF, or TOF.
Tracheoesophageal fistula Types
The condition could be classified into several types based on the structure and location of the fistula. Esophageal agenesis, absence or incomplete development of the esophagus, may be present in some forms of TEF.
Picture 1 – Tracheoesophageal fistula
Type A
Some patients have a maldeveloped esophagus without the fistula.
Type B
The upper segment of the esophagus, which ends in a blind sac, forms an abnormal connection with the trachea.
Type C
The upper section of the esophagus abnormally terminates in a blind-ended pouch. On the other hand, the lower esophageal segment is joined to the trachea by a fistula.
Type E or H
In this form, two segments of the esophagus joins the trachea. Therefore, two fistulas can be observed in such patients.
Tracheoesophageal fistula Symptoms
Polyhydramnios, or excessive secretion of amniotic fluid in the amniotic sac, is a common sign of TEF in the prenatal stage. In affected neonates, the symptoms aggravate during feeding, causing extreme discomfort and serious consequences. These include:
- Abdominal distension
- Profuse, white frothy bubbles of mucus in the mouth and nose
- Frequent coughing
- Vomiting
- Choking
- Fever
- Sucking in of food particles or fluids into the lungs
- Groaning noises while breathing
- Cyanosis, abnormal blue discoloration of the skin and mucous membranes
Tracheoesophageal fistula Causes
The tracheoesophageal septum usually divides the esophagus from the trachea. It forms when the tracheoesophageal folds undergo fusion. In TEF, however, the tracheoesophageal ridges may fail to fuse properly during the 3rd week of embryological development, causing posterior deviation of the septum and incomplete separation of the esophagus from the laryngotracheal tube, a precursor for the larynx and trachea. Inability of the septum to separate the trachea from the esophagus leads to formation of a tracheo-esophageal fistula. Presence of a central cavity in the fistula may allow passing of food and air into the esophagus and trachea respectively. Congenital TEF could be related to a chromosomal defect. Medical experts believe that three copies of chromosome 13, 18 and 21 may cause abnormal development of the Tracheoesophageal septum.
TEF cannot always be assumed as a congenital defect as the condition could occur in the later stages of life due to a number of reasons. In such cases, an individual suffers from acquired TEF. Some of its possible causes may include:
- Infection or injury due to a Tracheostomy tube
- Surgical excision of the larynx
- Blunt thoracic injuries
- Neck trauma
- Tremendous pressure exerted by a cuffed endotracheal tube during lung ventilation
- Lung cancer
Tracheoesophageal fistula Associated disorders
The existence of other anomalies has been noted in some children with TEF. These are:
- VACTERL association
- Laryngeal cleft
- Down syndrome
- Duodenal atresia
- Dysphagia
- Horseshoe kidney
- Polycystic kidney
- Malrotation
- Intestinal malformation
- Rib malformation
- Scoliosis
- Lower limb defect
Tracheoesophageal fistula Diagnosis
The condition could be diagnosed shortly after birth, owing to the presence of symptoms at the onset of feeding. Certain diagnostic procedures are conducted in order to locate the fistula for further confirmation.
Nasogastric intubation
In this medical process, a plastic tube also called nasogastric tube is inserted through the nose or throat and guided into the abdomen. Obstruction of the nasogastric tube at the esophageal level in TEF-affected newborns indicates a possible existence of a fistula.
X-ray
Radiographic examination of the chest assesses the state of the trachea, esophagus, heart and lungs as well as helps in detecting the underlying causes of acquired TEF such as:
- Fracture
- Tumor
- Accumulation of excess fluid in the pericardial or pleural cavity
Barium swallow
The imaging procedure involves ingestion of a barium meal in order to examine the condition of the upper gastrointestinal tract. With the help of a fluoroscope, images are taken as the contrast medium is swallowed. If patient shows difficulty in swallowing due to obstruction of esophagus, TEF is most likely to be present.
Bronchoscopy
In this method, a viewing tube is used to evaluate the lungs and airways of a person suspected of having the disorder. Direct inspection of the pulmonary tissues is not possible in this procedure. However, samples of the tissue or pleural fluid can be collected and examined for any tumor, nodule, inflammation or infection.
Gastrointestinal Endoscopy
An endoscope is used to view the upper gastrointestinal tract to spot the fistula. Biopsies can be collected for ruling out any abdominal disorders.
CT scan
Intravenous administration of a contrast dye, followed by a CT scan, can give distinct images of the lungs, trachea and heart. Individuals with TEF may show an abnormal passageway between the trachea and esophagus.
Tracheoesophageal fistula Differential Diagnosis
Physicians must segregate TEF from disorders sharing similar symptoms. Some of the common ones include:
- Esophageal Rupture
- Esophageal Cancer
- Esophagitis
- Tracheal Tumors
- Zenker Diverticulum
- Gastroesophageal Reflux Disease
Tracheoesophageal fistula Treatment
Acquired TEF can be corrected by treating its predominant causes. Some of the common methods of treatment used are:
Picture 2 – Tracheoesophageal fistula Image
Medications
Healthcare providers may administer antibiotics in case of an infection in the lungs or gastrointestinal tract.
Stenting
A small mesh tube called stent is inserted into the trachea or esophagus for facilitating proper passage of food and oxygen. It also seals leaks at the trachea-esophagus junction and does not cause reflux.
Pulmonary support
Depletion of oxygen in blood can hinder respiration and lead to complications in severe cases of TEF. Oxygen masks are primarily used by doctors for compensating the shortage of air. The therapeutic procedure can promote proper digestion as well as cellular metabolism. An endotracheal tube connected to a ventilator can be inserted through the mouth down into the trachea in order to permit air to pass freely to and from the lungs.
Surgery
Partial or complete surgical excision of the fistula followed by joining/anastomosing of the segments of the esophagus can repair TEF. In other cases, a small portion from the large bowel can be used to connect the discontinuous parts of esophagus. Endoscopic procedure is normally performed in young children.
Tracheoesophageal fistula Complications
The congenital and acquired forms of the disorder can lead to an array of complications. Some of these include:
- Acute respiratory distress
- Pneumonia
- Poor nutrition
- Bronchiectasis
- Lung abscess
- Abrupt esophageal motility
Tracheoesophageal fistula Prognosis
Post-surgery, the survival rate of infants is almost 100%. Presence of associated disorders can reduce the survival rate to 80-95%.
Tracheoesophageal fistula should be diagnosed immediately after birth before affected infants develop life-threatening complications. Although most sufferers can resume normal life post treatment, some of them may encounter problems with feeding and breathing. Regular follow-up is necessary for patients to ensure quick recovery.
