Tracheoesophageal Fistula (TEF)

Definition & Embryology

• The Developing Human: Clinically Oriented Embryology, p. 576
• Schwartz's Principles of Surgery, p. 1744

Anatomic Classification (5 Types)

• Schwartz's Principles of Surgery, p. 1745
• Tintinalli's Emergency Medicine, p. 3986

Associated Anomalies

• VACTERL association: Vertebral anomalies, Anal atresia, Cardiac defects, Tracheoesophageal fistula, Esophageal atresia, Renal anomalies, Limb anomalies
• CHARGE syndrome: Coloboma, Heart defects, Atresia choanae, Retardation of growth, Genital/urinary abnormalities, Ear abnormalities
• Specific breakdown in EA-TEF patients:
  • Cardiac defects: 38%
  • Skeletal defects: 19%
  • Neurological defects: 15%
  • Renal defects: 15%
  • Anorectal defects: 8%

• Schwartz's Principles of Surgery, p. 1745; Miller's Anesthesia, p. 10638

Clinical Presentation

• Excessive drooling from birth (unable to swallow secretions)
• Choking/coughing immediately upon feeding
• Cyanotic episodes during nursing
• Abdominal distention (air enters stomach via fistula during crying/coughing)
• Respiratory distress from aspiration - chemical pneumonitis from refluxed gastric acid passing through fistula into the trachea

• Presents later in infancy/childhood (esophagus is patent)
• Recurrent respiratory tract infections
• Chronic cough, particularly with feeds

• The Developing Human, p. 576; Cummings Otolaryngology, p. 2755

Diagnosis

1. Inability to pass an orogastric/NG tube into the stomach - tube coils in the upper pouch (stops 9-13 cm from nares). This is the classic bedside test.
2. Chest X-ray: Shows the coiled tube in the upper pouch; gastric bubble confirms a distal fistula (Type C); right upper lobe pneumonia from aspiration is common.
3. Contrast esophagram: Diagnostic - demonstrates the fistula and/or atresia. For H-type fistulas, a barium study is particularly useful.
4. Endoscopy: Useful as an alternative to contrast studies, especially to avoid aspiration risk.
5. Bronchoscopy: Used intraoperatively to confirm fistula size and location before repair.

Important differential: Esophageal perforation from traumatic NG tube insertion - typically occurs at the piriform sinus.

• Schwartz's Principles of Surgery, p. 1745; K.J. Lee's Essential Otolaryngology, p. 1131

Management

Preoperative / Initial Stabilization

• Withhold feeds; maintain upright (head-up, prone) positioning
• Place a Replogle tube (double-lumen sump catheter) in the upper esophageal pouch for continuous low-pressure suction of secretions
• IV fluids, antibiotics if pneumonitis is suspected
• Workup for associated anomalies (echo, abdominal US, spinal films)

Surgical Repair

• Primary anastomosis via right thoracotomy (or thoracoscopy) with ligation of the fistula at the trachea followed by esophageal anastomosis - this is the current standard approach
• Thoracoscopic repair is now the preferred approach in most centers
• Long-gap EA (gap >3 cm, or height of 2 vertebrae) is more challenging and may require:
  • Foker technique - external traction sutures to elongate the esophagus prior to anastomosis
  • Staged repair: gastrostomy followed by delayed primary anastomosis at ~3 months
  • Esophageal substitution: colonic interposition, gastric transposition, or free jejunal graft

Endoscopic Treatment

• Schwartz's Principles of Surgery, p. 1745; Cummings Otolaryngology, p. 2762

Anesthetic Considerations

1. Aspiration pneumonitis - compromises baseline respiratory function
2. Positive-pressure mask ventilation - forces air through the fistula into the stomach, causing gastric distention that splints the diaphragm and reduces FRC, making ventilation worse
3. ETT malplacement - the tube can inadvertently enter the fistula rather than the trachea

• Inhalational induction with spontaneous ventilation maintained until fistula is ligated
• Bronchoscopy after induction to assess fistula size and location; a balloon embolectomy catheter may be placed in the fistula to occlude it
• ETT placed distal to the fistula - can be done by advancing into a main bronchus then withdrawing until bilateral air entry is confirmed
• If large fistula or poor lung compliance: urgent transcutaneous gastric decompression or intra-abdominal clamping of the distal esophagus may be needed
• Invasive arterial BP monitoring recommended
• Pre- and post-ductal pulse oximetry to detect intracardiac shunting

• Miller's Anesthesia, pp. 10638-10639

Complications

• Anastomotic leak
• Esophageal stricture (most common - occurs in ~30-40%)
• Recurrent fistula

• Esophageal dysmotility
• GERD (very common)
• Tracheomalacia (TM)
• Only ~20% of patients with repaired EA have normal pulmonary function at long-term follow-up (Helsinki study)

Prognosis

• K.J. Lee's Essential Otolaryngology, p. 1133; Schwartz's Principles of Surgery, p. 1744

Anaesthetic Management of a Neonate with Tracheoesophageal Fistula

1. Preoperative Assessment

Understanding the Pathophysiology - Why It Matters for Anaesthesia

• Aspiration pneumonitis - gastric contents reflux up the distal esophagus and enter the trachea through the fistula; saliva pools in the upper pouch and overflows
• Positive-pressure ventilation (PPV) before fistula ligation - gas preferentially takes the path of least resistance through the fistula into the stomach, causing progressive gastric distention that:
  • Splints the diaphragm and reduces functional residual capacity (FRC)
  • Makes lung ventilation progressively harder, causing a vicious cycle
  • Risk is proportional to fistula size and inversely proportional to lung compliance
• ETT malplacement into the fistula - the fistula orifice is usually on the posterior membranous wall of the trachea, just proximal to the carina; the ETT tip can enter it
• Coexisting congenital heart disease - present in 15-38% of cases; can profoundly alter anaesthetic conduct

Preoperative Workup (Before Anaesthesia)

Optimisation Before Theatre

• Nil by mouth - feeds withheld
• Replogle tube (sump catheter) placed in the upper esophageal pouch on continuous low-pressure suction - prevents aspiration of pooled saliva
• Positioning - nurse upright prone (head-up, prone position) to reduce gastric reflux through the fistula into the trachea
• IV antibiotics if aspiration pneumonitis is present
• IV fluids for hydration and electrolyte correction
• Rarely, if pneumonitis is severe, a gastrostomy under local anaesthesia may be performed first to protect the pulmonary system, followed by delayed definitive repair

Definitive repair is rarely a surgical emergency. If the infant is haemodynamically stable and oxygenating well, repair may proceed within 24-48 hours - this allows time for full anomaly workup and assembly of an experienced team.

• Barash's Clinical Anesthesia, p. 3664-3665; Morgan & Mikhail's Clinical Anesthesiology, p. 1715

2. Monitoring

• Precordial (or oesophageal) stethoscope placed in the dependent (left) axilla - during right thoracotomy with the infant in the left lateral position, surgical retraction can obstruct the left mainstem bronchus; a sudden drop in breath sounds signals the need to re-expand the retracted lung
• Invasive arterial line (usually right radial) - for beat-to-beat BP monitoring; surgical retraction can compress great vessels causing sudden hypotension
• Pre- and post-ductal pulse oximetry (right hand = preductal; foot = postductal) - detects intracardiac shunting
• SpO₂ continuous
• Capnography (ETCO₂)
• Temperature monitoring - neonates are at high risk of hypothermia
• Urinary catheter
• Miller's Anesthesia, p. 10639; Morgan & Mikhail's, p. 1716

3. Induction and Airway Management

The Core Principle

Three Accepted Approaches to Intubation

• Inhalation induction with sevoflurane or halothane in oxygen
• Topical lidocaine spray to the larynx
• Intubate while spontaneous ventilation is maintained - no muscle relaxant
• Spontaneous breathing throughout until fistula is ligated

• Risk: controlled ventilation via mask before ETT placement will distend stomach via fistula
• If this route is used, minimize mask ventilation time and use gentle pressures
• Gastrostomy tube (if present) must be left open to air to vent stomach distension

• Protects airway while reducing aspiration risk
• Useful in very sick or extremely premature neonates

Modern practice generally favours Option 1 (inhalational induction, spontaneous ventilation). Options 2 or 3 may be necessary when spontaneous ventilation is not achievable.

• Barash's Clinical Anesthesia, p. 3665; Morgan & Mikhail's, p. 1715-1716

ETT Positioning - The Critical Step

1. Advance the ETT deliberately into a mainstem bronchus (unilateral chest expansion + unilateral breath sounds confirm endobronchial position)
2. Slowly withdraw until bilateral chest movement and bilateral breath sounds are confirmed
3. The tip is now distal to the fistula but proximal to the carina

• Confirm fistula location and size
• Guide ETT placement
• A balloon embolectomy (Fogarty) catheter may be passed directly into the fistula to occlude it - this is particularly useful when the fistula is large or when adequate ventilation cannot be maintained

• Withdraw the tube immediately
• The surgeon can confirm by palpating the tube tip in the fistula
• If gasric distension is extreme and ventilation impossible:
  • Transcutaneous gastric decompression (needle/trocar)
  • Intra-abdominal clamping of the distal esophagus via abdominal incision
  • Emergent thoracotomy with fistula ligation as a last resort
• Barash's Clinical Anesthesia, p. 3665-3666; Miller's Anesthesia, p. 10638-10639

4. Maintenance of Anaesthesia

• Volatile agent (sevoflurane/isoflurane) in oxygen - most neonates with TEF require 100% oxygen or high FiO₂ due to pre-existing pulmonary compromise
• Spontaneous ventilation is maintained until the fistula is ligated; after ligation, controlled ventilation with the lowest effective pressures and tidal volumes
• Muscle relaxants are used cautiously and only after fistula ligation in most cases; if used before ligation, the gastrostomy tube must be open
• Gastrostomy tube (if present) - kept open to air at the head of the table under the anaesthetist's direct observation; prevents kinking or obstruction; allows venting of gastric air during PPV
• Opioids - used sparingly in neonates planned for early extubation; moderate doses may necessitate postoperative ventilation
• Neuraxial anaesthesia (caudal catheter threaded to thoracic level, or paravertebral block) - adjunct to reduce volatile agent requirements, limit muscle relaxant use, reduce opioid need, and facilitate early extubation

Surgical Position and Intraoperative Concerns

• Patient in left lateral decubitus position for right thoracotomy (conventional left-sided aortic arch)
• For right-sided aortic arch, approach is based on surgeon preference (either side)
• During surgery: retraction of mediastinal structures can cause:
  • Obstruction of left mainstem bronchus - detected by precordial stethoscope in left axilla
  • Compression of great vessels (hypotension) - detected by arterial line
  • Compression of vagus nerve (bradycardia)
  • Lung retraction causing desaturation - surgeon must re-expand lung as needed

Thoracoscopic (VATS) Repair

• Now the most common approach at experienced centres
• Anaesthetic principles are the same
• Additional challenges: single-lung ventilation in a neonate is technically demanding; hypercapnia and hypothermia are more pronounced; CO₂ insufflation for thoracoscopy can worsen hypercapnia and reduce venous return
• Barash's Clinical Anesthesia, p. 3665-3666; Morgan & Mikhail's, p. 1715-1716; Miller's Anesthesia, p. 10639

5. Special Situation: H-Type (Type E) Fistula

1. Direct laryngoscopy and rigid bronchoscopy under spontaneous ventilation to identify the fistula
2. A guidewire is passed through the fistula tract into the esophagus
3. The infant is intubated carefully, without dislodging the wire
4. Esophagoscopy is performed; the guidewire is visualised and brought out through the mouth
5. Fluoroscopy determines the fistula level and guides choice of cervical vs. thoracic surgical approach
6. Intraoperatively, the anaesthetist applies traction to the wire loop to help the surgeon localise the fistula

• Barash's Clinical Anesthesia, p. 3666

6. Management of the Premature Neonate with TEF

• High airway pressures required for RDS force large volumes of air through the fistula into the stomach
• Progressive gastric distension further compromises already poor lung compliance
• Moving the ETT tip distal to the fistula or placing a balloon catheter in the fistula may improve ventilation
• Emergent gastrostomy (tube placed to water seal, analogous to a chest drain) can allow fistula air to escape while permitting some positive pressure ventilation
• May require urgent thoracotomy with fistula ligation before full stabilisation
• Sabiston Textbook of Surgery, p. 2679

7. Postoperative Management

Extubation Decision

• If extubation is planned at end of surgery, tailor the anaesthetic technique accordingly: neuraxial analgesia + low volatile + minimal relaxants + minimal/no opioids
• If postoperative ventilation is required: keep head in neutral position; avoid neck extension; PEEP as appropriate

Critical Postoperative Precautions

• Neck extension is strictly avoided - can disrupt the esophageal anastomosis
• Esophageal instrumentation (e.g., NG tube advancement) is prohibited until cleared by the surgeon - blind suctioning past the anastomosis can disrupt the repair
• Gastrostomy tube remains in situ if placed; used for feeds while anastomosis heals

Postoperative Analgesia

• Wound infiltration with local anaesthetic
• Caudal catheter threaded to thoracic level - continuous infusion or intermittent bolus of local anaesthetic
• Paravertebral block (ultrasound-guided, unilateral) - excellent for ipsilateral hemithorax
• Systemic opioids used sparingly given respiratory concerns

Postoperative Complications to Monitor

• Barash's Clinical Anesthesia, p. 3666-3667; Morgan & Mikhail's, p. 1716

Summary: Key Anaesthetic Principles at a Glance