Anesthesia for endotracheal stenting or repair of tracheoesophageal fistula

INTRODUCTION — This topic will discuss anesthetic management for adult patients undergoing endotracheal stenting or repair of tracheoesophageal fistula (TEF) via stent occlusion or open surgery. Anesthetic management of other tracheal surgical procedures is addressed in separate topics.

●(See "Anesthesia for tracheostomy".)

●(See "Anesthesia for tracheal resection and reconstruction".)

PREANESTHETIC ASSESSMENT — Considerations for preanesthetic assessment are similar to those for patients undergoing tracheal resection. This includes details regarding the tracheal lesion (its precise location, size, stability, and likelihood to bleed or otherwise compromise airway patency) and plans for anesthetic induction. (See "Anesthesia for tracheal resection and reconstruction", section on 'Preanesthetic assessment'.)

Additional considerations for selected patients include:

●Management of patients with a tracheal stent already in place – Preoperative planning and discussion with the surgical team are essential because a previously placed stent must not be dislodged or even touched during anesthetic induction and airway control. The location of the stent is determined with preoperative radiographic studies. There may be adequate space above a stent in the distal trachea, such that an endotracheal tube (ETT) can be inserted via a flexible intubating bronchoscope and positioned without touching the stent. However, if preoperative imaging reveals inadequate tracheal length such that an ETT cannot be inserted above the stent, then the best plan may be to use a supraglottic airway (SGA).

●Management of patients undergoing repair of TEF – Additional considerations in the immediate preoperative period for patients with TEF are discussed below. (See 'Preoperative considerations on the day of surgery' below.)

In all cases, the surgical approach and planned interventional sequence are discussed with the surgical team. This includes planned positioning, location of any incision(s), and timing and sequence for use of flexible and/or rigid bronchoscopy. (See "Anesthesia for tracheal resection and reconstruction", section on 'Preinduction communication'.)

PREPARATION OF ANESTHETIC EQUIPMENT — Preparations for any tracheal surgical procedure include ensuring availability and proper function of all equipment that may be necessary during induction of anesthesia and subsequent surgical interventions. This includes an assortment of regular endotracheal tubes (ETTs), as well as wire-reinforced "armored" ETTs (picture 1) in all sizes from 7.0 mm inner diameter (ID) down to the smallest available cuffed sizes, and all possible stent choices. If the fistula is close to the carina or involves a bronchus, a long single-lumen ETT (picture 2), double-lumen ETT (DLT), and/or a bronchial blocker device may be needed (see "Lung isolation techniques"). Supraglottic airway (SGA) devices should also be available (see "Supraglottic devices (including laryngeal mask airways) for airway management for anesthesia in adults"). Furthermore, flexible and rigid bronchoscopes should be ready for use. These details are discussed in a separate topic. (See "Anesthesia for tracheal resection and reconstruction", section on 'Preparation of anesthetic equipment'.)

Finally, the surgeon should be available prior to and during induction to help execute plans for airway rescue if necessary. (See "Anesthesia for tracheal resection and reconstruction", section on 'Specific strategies'.)

INSERTION OF AN ENDOTRACHEAL STENT

Procedural considerations — An endotracheal stent provides tracheal support to improve or maintain airway patency in patients with a tracheal mass, stenosis, or collapse, and sometimes to cover and protect a weakened tracheal wall [1]. These stents may be straight or bifurcated at the end (picture 3 and picture 4) [1]. Less commonly, placement of a stent may be necessary to occlude a tracheal laceration or fistula. Stents may be "off the shelf" items but often are customized. Before induction, the surgical team should confirm that all possible stent choices are available in the operating room. (See "Airway stents".)

The surgeon may deploy the stent by using a forceps via a transoral or stomal route, or through an orally inserted rigid or flexible bronchoscope [1]. If placement is through a mature tracheostomy stoma into an intact trachea, the airway will be reliably accessible throughout the procedure. (See "Airway management for anesthesia for the patient with a tracheostomy".)

Anesthetic technique

Local anesthesia — In selected cases it is possible to place a stent via a flexible bronchoscope with local anesthetic applied to the airway by the surgeon. Examples include expandable metal stents that can be gently and quickly deployed into position and do not need removal for sizing (table 1) [2]. Supplemental sedation is typically necessary. (See "Anesthesia for adult bronchoscopy", section on 'Anesthetic techniques for flexible bronchoscopy'.)

General anesthesia — Deep general anesthesia is necessary for most stent insertions, particularly if the device is deployed via a rigid bronchoscope. We prefer a total intravenous anesthesia (TIVA) technique that includes administration of a neuromuscular blocking agent (NMBA) to prevent patient movement that may cause tracheal injury. (See "Anesthesia for adult bronchoscopy", section on 'General anesthesia for rigid bronchoscopy'.)

Airway and ventilation management

●Airway management – In some cases, the surgeon can deploy the stent while the patient is transorally ventilated via an oxygen mask, supraglottic airway (SGA), or endotracheal tube (ETT).

In patients with a tracheostomy, manual occlusion of the tracheal stoma may be required to achieve adequate ventilation via a transoral airway device. If ventilation via the tracheal stoma becomes necessary during the procedure, a wire-reinforced "armored" ETT is selected for insertion into the stoma to minimize the risk of ETT kinking (picture 1).

●Ventilation management – Ventilation is typically controlled. In one randomized study of 64 patients undergoing airway stenting, controlled ventilation after administration of an NMBA resulted in a lower incidence of desaturation events (defined as percutaneous oxygen saturation [SpO₂] <95 percent) compared with allowing spontaneous respiration (10 versus 75 percent) [3].

Typically, the bronchoscope and stent are inserted, then repeatedly repositioned or removed to adjust limb lengths for an optimal tracheal fit. This technique requires periods of intermittent ventilation. For critical tracheal stenosis requiring urgent or emergency stenting, ventilation strategies are individualized depending on the location (and cause) of tracheal narrowing [4].

Extubation and recovery — Before extubation and after discussion with the surgeon, dexamethasone 8 to 10 mg is typically administered to reduce airway and vocal cord swelling.

Prior to emergence, a final inspection and suctioning of the trachea and bronchi to remove any secretions or blood in the airway is essential, as well as communication with the surgeon regarding their satisfaction with hemostasis and position of the stent. Residual bleeding and clot formation may compromise airway patency on emergence. Additionally, airway compromise may occur if the stent does not fit well or drifts into malposition in a patient with a dynamic tracheal lesion. In such cases, repositioning or removal of the stent would be necessary.

Safe emergence and recovery require a high level of vigilance. Continued close observation for one to two hours during the early postoperative period is necessary to verify airway patency. Administration of any long-acting opioid is avoided since insertion of an endotracheal stent or T-tube produces little or no postoperative pain. Furthermore, oversedation is particularly risky in the immediate postoperative period when airway patency may be tenuous.

For patients with repetitive cough and a primary complaint of feeling a foreign body in the trachea, low doses of a short-acting opioid (eg, fentanyl 25 to 50 mcg) may be judiciously administered to blunt the cough reflex and discomfort after confirmation that the airway is patent.

OPEN REPAIR OR STENT OCCLUSION OF TRACHEOESOPHAGEAL FISTULA — Tracheoesophageal fistulae (TEFs) are patent connections between the respiratory and upper gastrointestinal (GI) tract (picture 5). A TEF may be present at birth due to a genetic variant or may form later in life as a result of an inflammatory process, neoplasm, or trauma to the respiratory tract and/or esophagus (table 2). The precise location of a TEF varies. Most acquired TEFs are proximal (ie, at the cervicothoracic junction). However, a TEF forming after crush injury to the chest is typically located at the carina. Other etiologies may occur anywhere along the trachea. (See "Tracheo- and broncho-esophageal fistulas in adults".)

Procedural considerations — An occlusive tracheal stent (silicone or self-expanding metallic) may be deployed for palliation of a TEF due to a malignant tracheal or esophageal lesion, or to serve as a bridge if surgery must be deferred (picture 6). (See "Anesthesia for esophagectomy and other esophageal surgery", section on 'Repair of tracheoesophageal fistula'.)

Tracheal stents may be positioned via flexible or rigid bronchoscopy and, in some cases, are combined with an esophageal "kissing stent" placed via esophagoscopy (picture 7). (See "Anesthesia for esophagectomy and other esophageal surgery", section on 'Repair of tracheoesophageal fistula'.)

For patients who require open repair, a transverse low "collar" incision that may be extended via a partial sternotomy is typically accomplished in the supine position. However, if the TEF is distally located, a right thoracotomy in the left lateral decubitus position may be selected by the surgeon.

Preoperative considerations on the day of surgery

●Re-evaluate airway patency on the day of surgery since some tracheal lesions may rapidly progress. (See "Anesthesia for tracheal resection and reconstruction", section on 'Re-evaluation on the day of surgery'.)

●Confirm adequate treatment of any pulmonary infection due to aspiration.

●For elective cases, confirm that malnutrition has been adequately treated. (See "Overview of prehabilitation for surgical patients", section on 'Nutritional supplementation'.)

●Confirm that usual medications such as proton pump inhibitors and acid suppression therapy were administered on the morning of surgery.

●Achieve consensus regarding planned techniques for anesthetic induction, tracheal intubation, positioning of the end of the endotracheal tube (ETT), and maintaining oxygenation and ventilation during the procedure. (See "Anesthesia for tracheal resection and reconstruction", section on 'Key points for the surgical briefing'.)

●Discuss the planned surgical incision and postoperative pain management. If a right thoracotomy is planned, a thoracic epidural (TEA) or paravertebral block (PVB) catheter is placed, typically before induction of general anesthesia to facilitate postoperative pain control, as well as for supplementation of intraoperative analgesia. (See "Anesthesia for open pulmonary resection", section on 'Post-thoracotomy pain management'.)

Local anesthesia — In selected cases, when flexible bronchoscopy is employed, stent placement may be possible using local anesthesia plus sedation, similar to placement of an endotracheal stent for other indications. (See 'Local anesthesia' above.)

General anesthesia — General anesthesia is necessary for open repair of TEF, or for stent occlusion if a rigid bronchoscope is used.

Preinduction strategies — Patients with TEF are at high risk for pulmonary aspiration of gastric contents that have seeped through the fistula tract. Applying cricoid pressure during anesthetic induction is not protective. Strategies to minimize gastric insufflation and risk for soilage of the trachea via the fistula tract include:

●Elevate the head of the bed to a 30 degree angle to both reduce this risk and improve the functional residual capacity of lungs that may be chronically damaged by pulmonary aspiration.

●Preoxygenate with 100 percent oxygen to increase oxygen reserve and provide additional time to secure the airway [5]. (See "Rapid sequence induction and intubation (RSII) for anesthesia", section on 'Preoxygenation'.)

●Evacuate GI contents under direct visualization via an esophagoscope before induction. Typically, this is accomplished by the surgeon after numbing the oropharynx. In some cases, the surgeon may position a nasogastric or orogastric tube for later evacuation of stomach contents. Blind instrumentation of the esophagus is avoided.

Induction and initial airway management — Tracheal intubation must isolate the TEF while avoiding tracheal soiling with gastric contents. A flexible bronchoscope should always be used for intubation and ETT positioning to ensure that the tip of the ETT stays within the trachea (and does not follow the fistula tract) and that the cuff is positioned in the trachea beyond the fistula. In some cases, the selected tube is advanced over the flexible bronchoscope beyond the fistula into the opposite bronchus so that one lung ventilation (OLV) can be initiated. Then, if necessary, the nonventilated lung can be isolated from the fistula by a bronchial blocker. (See "Lung isolation techniques".)

Blind tracheal intubation is avoided, as this may result in inadvertently traversing the fistula tract with intubation of the esophagus or mediastinum. Also, avoid positive pressure ventilation (PPV) until the fistula is isolated by placement of the ETT cuff beyond the TEF.

●Intubation strategies

•Induction of anesthesia followed by tracheal intubation – If efficient tracheal intubation can be ensured, general anesthesia may be induced, but PPV by mask is avoided. Specific techniques to accomplish this include:

-Rapid sequence induction and intubation (RSII) – RSII is selected if it is likely that the airway can be easily secured in a patient with unambiguous airway anatomy. If succinylcholine is used, we administer a defasciculating dose of a nondepolarizing neuromuscular blocking agent (NMBA) before succinylcholine to reduce the intragastric pressure increase that would otherwise occur [6,7]. (See "Rapid sequence induction and intubation (RSII) for anesthesia" and "Rapid sequence induction and intubation (RSII) for anesthesia", section on 'Defasciculation'.)

-Induction of general anesthesia followed by insertion of a supraglottic airway (SGA) – An SGA may be inserted immediately after induction of general anesthesia to facilitate a quick inspection of the trachea via the flexible bronchoscope, before inserting the ETT (which may cover up the pathology). Subsequently, the SGA is removed and the ETT can be inserted over the flexible bronchoscope for final positioning. As above, this strategy is selected only in patients with straightforward, easily identified anatomy and an expected expeditious intubation.

•Preservation of spontaneous ventilation until after tracheal intubation – If potentially difficult airway anatomy is anticipated, then preservation of spontaneous ventilation until after tracheal intubation may be a safer choice. Suspicion for difficult anatomy should be high in patients with chronic gastric spillage into the trachea and severe tracheal inflammation that may distort anatomic landmarks. This and/or copious secretions create challenges in distinguishing trachea from esophagus or fistula tract during bronchoscopic examination and may increase the time required to secure/isolate the airway.

For such patients, inhalation induction of general anesthesia while maintaining spontaneous ventilation is typically selected to allow additional time to visualize anatomic structures. This technique avoids PPV (and the associated risk of gastric insufflation) until the fistula has been isolated by a properly positioned ETT. (See "Inhalation anesthetic agents: Clinical effects and uses", section on 'Inhalation induction (sevoflurane, halothane, nitrous oxide)'.)

•Awake intubation – Awake intubation is another strategy that may be selected if ambiguous anatomy is suspected in order to preserve spontaneous ventilation and avoid PPV until the fistula has been isolated. In some cases, the surgeon may need to inspect the fistula and then place and position the ETT via a flexible bronchoscope in an awake spontaneously breathing patient.

This technique is accomplished after numbing the airway with topically applied local anesthetic and/or use of airway nerve blocks. Notably, adequate topicalization is challenging if excessive secretions are present. (See "Awake tracheal intubation", section on 'Airway anesthesia'.)

●Additional considerations after intubation

•Before initiating PPV, verify correct ETT position via flexible bronchoscopy, ensuring that its tip is within the tracheal lumen (and not out through the fistula tract) and that it has been advanced far enough to allow the cuff to be distal to the fistula and above the carina. Avoiding PPV until the fistula has been isolated prevents gastric insufflation and pressurization. If the trachea has been grossly soiled, a flexible bronchoscope should be used to suction and clean the distal airways prior to initiating PPV.

•Initiate controlled PPV with low pressure settings after confirming ETT positioning. Start at 10 to 15 cm H₂O for a target tidal volume (TV) of 4 to 6 mL/kg. Typically, the fraction of inspired oxygen (FiO₂) is initially set at 100 percent, then reduced to the lowest level that maintains adequate oxygen saturation (measured with pulse oximetry). Administration of an NMBA facilitates controlled ventilation and oxygenation. Also, lung recruitment maneuvers may be carefully initiated.

•Subsequent maintenance of optimal lung protective controlled ventilation is discussed separately. (See "Mechanical ventilation during anesthesia in adults", section on 'Lung protective ventilation during anesthesia'.)

●Considerations for a distally located TEF – Patients with a distally located TEF near the carina require special management. A long single-lumen tube (picture 2) or a double-lumen ETT (DLT) may be suitable. If it is not possible to inflate the tracheal cuff of the DLT due to proximity to the TEF, then a bronchial blocker is used to isolate the nonventilated lung from the TEF and prevent soiling via the fistula. DLT and bronchial blocker devices are described in detail separately. (See "Lung isolation techniques".)

Maintenance of anesthesia and airway management — After general anesthesia has been induced and the airway has been secured, the surgeon will re-evaluate tracheal and esophageal pathology using both bronchoscopy and esophageal endoscopy.

If the ETT is positioned beyond the fistula, it may be necessary to pull it back intermittently during the surgical repair to visualize and access the TEF. PPV is avoided whenever the fistula is exposed; instead, intermittent ventilation is employed during these periods.

Since inhalation anesthetic delivery and end-tidal measurements of exhaled concentration are unreliable during intermittent ventilation, we employ a total intravenous anesthesia (TIVA) technique during the maintenance phase of general anesthesia to ensure adequate anesthetic depth. (See "Maintenance of general anesthesia: Overview", section on 'Total intravenous anesthesia'.)

Extubation and recovery

●Extubation – Typically, tracheal extubation is accomplished at the end of the surgical procedure while the patient is still in the operating room [8,9]. The surgeon must be present.

Just before emergence from general anesthesia, the surgeon may inspect and further clean the airway with a flexible bronchoscope inserted via the existing ETT. In some cases, the ETT is exchanged for an SGA before emergence so that further bronchoscopic examination of the vocal cords can be accomplished to address any concerns regarding vocal cord swelling or injury to the recurrent laryngeal nerve that may create postoperative respiratory distress. (See "Overview of the management of postoperative pulmonary complications".)

●Recovery – Following extubation, positive pressure airway support is used judiciously. Reintubation is avoided if possible. However, if reintubation becomes necessary, the surgeon typically uses a small-diameter ETT inserted over a flexible bronchoscope.

Other aspects of anesthetic management after extubation, including transport to the intensive care unit for observation and postoperative pain management, are similar to those after tracheal resection and reconstruction. (See "Anesthesia for tracheal resection and reconstruction", section on 'Postoperative management'.)

SUMMARY AND RECOMMENDATIONS

●Preanesthetic assessment – Considerations for preanesthetic assessment are similar to those for patients with other tracheal pathology. Additional considerations for patients with a previously placed endotracheal stent are noted above. (See 'Preanesthetic assessment' above and "Anesthesia for tracheal resection and reconstruction", section on 'Preanesthetic assessment'.)

●Preparation of anesthetic equipment – Preparations include ensuring availability of all possible stent choices, an array of endotracheal tubes (ETTs), supraglottic airway (SGA) devices, and other airway equipment. (See "Anesthesia for tracheal resection and reconstruction", section on 'Preparation of anesthetic equipment'.)

●Insertion of an endotracheal stent

•Procedural considerations – Endotracheal stents (table 1 and picture 3 and picture 4) may be inserted via a transoral or stomal route using forceps, or deployed through a rigid bronchoscope. (See 'Procedural considerations' above.)

•Local anesthesia – In selected cases when an expandable metal stent can be gently and quickly deployed via a flexible bronchoscope, local anesthesia plus sedation may be adequate. (See 'Local anesthesia' above and "Anesthesia for adult bronchoscopy", section on 'Topical airway anesthesia with sedation'.)

•General anesthesia – Deep general anesthesia is necessary if rigid bronchoscopy is used. We employ a total intravenous anesthesia (TIVA) technique with administration of a neuromuscular blocking agent (NMBA) to prevent patient movement that may cause tracheal injury. (See 'General anesthesia' above.)

•Airway and ventilation management – If transoral ventilation is feasible, an oxygen mask, SGA, or ETT may be used. For ventilation via a tracheal stoma, a wire-reinforced "armored" ETT is selected to minimize risk of kinking (picture 1). Ventilation is typically controlled, with periods of intermittent ventilation and removal of the ETT. (See 'Airway and ventilation management' above.)

•Extubation and recovery – We suggest administration of dexamethasone 8 to 10 mg prior to extubation if airway and vocal cord swelling is likely (Grade 2C). Avoid long-acting opioids since postoperative pain is minimal and oversedation increases risk of airway compromise. Low doses of a short-acting opioid (eg, fentanyl 25 to 50 mcg) may be judiciously administered to blunt the cough reflex in stable patients complaining of discomfort due to a tracheal foreign body. (See 'Extubation and recovery' above.)

●Tracheoesophageal fistula – Tracheoesophageal fistulae (TEFs) are patent connections between the respiratory and upper gastrointestinal (GI) tract (picture 5).

•Procedural considerations – In some cases, an occlusive tracheal stent (self-expanding metallic) is positioned via flexible or rigid bronchoscopy (picture 6), sometimes combined with an esophageal "kissing stent" placed via esophagoscopy (picture 7). For open repair, surgical options include a transverse low "collar" incision that may be extended via a partial sternotomy in the supine position, or a right thoracotomy in the left lateral decubitus position for a distally located TEF. (See 'Procedural considerations' above.)

•Considerations on the day of surgery – (See 'Preoperative considerations on the day of surgery' above.)

-Re-evaluate airway patency.

-Confirm adequate treatment of any aspiration-related pulmonary infection.

-Confirm administration of usual medications (eg, proton pump inhibitors, acid suppression therapy) on the morning of surgery.

-Plan techniques for anesthetic induction, tracheal intubation, positioning the end of the ETT, and maintaining oxygenation and ventilation.

-If a thoracotomy is planned, a thoracic epidural (TEA) or paravertebral block (PVB) catheter is usually placed for pain control. (See "Anesthesia for open pulmonary resection", section on 'Post-thoracotomy pain management'.)

•Anesthetic choice – General anesthesia is necessary for open repair of TEF, or if a stent for occlusion is deployed using a rigid bronchoscope. (See 'General anesthesia' above.)

•Preinduction strategies – Preinduction strategies to minimize gastric insufflation and risk for tracheal soilage via the fistula tract include elevating the head of the bed by 30 degrees, preoxygenation, and evacuating stomach contents via esophagoscopy performed by the surgeon. (See 'Preinduction strategies' above.)

•Initial airway management

-Avoid blind tracheal intubation, which may inadvertently traverse the fistula tract and intubate the esophagus or mediastinum. Intubation strategies include (see 'Induction and initial airway management' above):

-Rapid sequence induction and intubation (RSII) if airway anatomy can be easily secured.

-Inhalation induction of general anesthesia while maintaining spontaneous ventilation if potentially difficult airway anatomy is anticipated.

-Awake intubation of a spontaneously breathing patient.

-For distal TEF close to the carina, a long single-lumen ETT (picture 2), double-lumen ETT (DLT), and/or bronchial blocker. (See "Lung isolation techniques".)

•Considerations after intubation – Avoid positive pressure ventilation (PPV) until the fistula is isolated by placing the ETT cuff beyond the TEF. Then use PPV with low pressure settings. Recruitment maneuvers may be carefully initiated.

•Anesthetic and airway management during maintenance – If the ETT is positioned beyond the fistula, it is pulled back intermittently to access the TEF during the surgical repair. Intermittent ventilation is employed, and PPV is avoided whenever the fistula is exposed. We use a TIVA technique because inhalation anesthetic delivery and end-tidal measurements of exhaled concentration are unreliable during intermittent ventilation. (See 'Maintenance of anesthesia and airway management' above.)

•Extubation and recovery – Before extubation, flexible bronchoscopy via the existing ETT is used to inspect and further clean the airway. Then the ETT is exchanged for an SGA to allow further bronchoscopic examination of the vocal cords to rule out cord swelling or recurrent laryngeal nerve injury. Following extubation, judicious positive pressure airway support is employed. Reintubation is usually avoided but can be performed by the surgeon with a small-diameter ETT inserted over a flexible bronchoscope if necessary. Patients are transported to the intensive care unit for observation and postoperative pain management. (See 'Extubation and recovery' above.)