INTRODUCTION — Elective or emergency tracheal surgical procedures are typically performed to improve tracheal patency or repair loss of tracheal integrity. Anesthetic challenges can include abnormal airway anatomy and physiology, requirements for specialized endotracheal tubes (ETTs) and additional airway devices to meet evolving intraoperative needs, and changes to alternative modes of ventilation (eg, jet ventilation [JV], intermittent ventilation) if the trachea is open or obstructed.
This topic will discuss anesthetic management of adult patients undergoing specific procedures involving the trachea from the distal edge of the larynx to the tracheal bifurcation at the carina.
General considerations for anesthetic management of tracheal surgery (eg, preoperative assessment and planning; anesthetic techniques for induction, maintenance, and emergence from general anesthesia; options for oxygenation and ventilation; management of postoperative pain) are discussed in a separate topic. Considerations for patients with novel coronavirus disease 2019 (COVID-19) who require tracheostomy are also addressed in that topic. (See "Anesthesia for tracheal surgery: General considerations".)
Other topics discuss anesthetic management of patients undergoing surgical or other invasive procedures involving the larynx, bronchi, or esophagus:
●(See "Anesthesia for head and neck surgery".)
●(See "Anesthesia for adult bronchoscopy".)
●(See "Anesthesia for esophagectomy and other esophageal surgery".)
TRACHEOSTOMY — A tracheostomy is performed to bypass pathology that compromises upper airway patency, or to provide access for ventilation support by creating a tracheal stoma with insertion of a tracheostomy tube (cuffed or uncuffed) below the larynx. The surgical approach is midline at the neck approximately midway between the cricoid cartilage and the sternal notch, usually through the second and third tracheal rings. The patient is placed in a supine position with the upper back slightly elevated and the head extended in order to stabilize the trachea and improve surgical exposure.
Open tracheostomy
General considerations — Important aspects of anesthetic management during a tracheostomy procedure include:
●Protection of the patient's eyes with tape before surgical prepping and draping. (See "Postoperative visual loss after anesthesia for nonocular surgery", section on 'Corneal abrasion'.)
●Confirmation that the endotracheal tube (ETT) cuff pressure is adequate for airway protection prior to surgical incision.
●Suctioning of potentially copious secretions that may pool in the oropharynx prior to draping and again before deflation of cuff and withdrawal of the ETT.
●Appropriate control of oxygen and ignition source, particularly during open tracheostomies, which carry the highest risk of intraoperative airway fire (see "Fire safety in the operating room" and "Anesthesia for tracheal surgery: General considerations", section on 'Preoperative team planning'):
•Ensure that the oxygen concentrations within the airway (both the fraction of inspired oxygen concentration [FiO2] and the fraction of expired oxygen concentration [FeO2]) are <30 percent once the closed trachea is exposed in the presence of an ignition source (eg, the electrosurgery [ESU] unit) [1]. Often three to five minutes are necessary to allow the FeO2 to be reduced to <30 percent. (See "Fire safety in the operating room", section on 'Special precautions during airway surgery'.)
Medical air should be used to dilute the oxygen concentration. Since nitrous oxide (N2O) supports combustion similar to oxygen, it is never an appropriate diluent for oxygen.
The oxygen analyzer is monitored to ensure that a FiO2 <30 percent is the actual delivered oxygen concentration and the expired concentration goal of <30 percent is met. We never simply reduce flow of 100 percent oxygen delivered through an open source such as a facemask or nasal cannula, as this will result in nonhomogeneous zones of oxygen concentrations, and is not condoned by the Anesthesia Patient Safety Foundation (APSF) or the Emergency Care Research Institute (ECRI).
•Other precautions to avoid airway fire in this setting include minimizing oxygen buildup by configuring the surgical drapes to be "open" to prevent accumulation of oxygen underneath them, flushing the surgical field with medical air, and scavenging the operating field with a suctioning device when an ESU is being used. (See "Fire safety in the operating room", section on 'Drapes, towels, sponges, and gauzes'.)
•Prior to opening the trachea, the surgeon, nurses, and anesthesiologist must verify that the ESU has been handed off the surgical field. Then the FiO2 is increased to 1.0 prior to manipulation of the ETT (but only after the ESU is no longer on the surgical field). (See "Safety in the operating room", section on 'Timeouts'.)
•Clear communication with the surgeon is necessary, particularly while pulling back the ETT to allow surgical insertion of the tracheostomy tube, as well as after connection of the new tracheostomy tube to the circuit to verify adequacy of ventilation. (See "Safety in the operating room", section on 'Structured communication'.)
A quiet and nondistracting operating room is essential. (See "Safety in the operating room", section on 'Techniques to minimize distractions and disruptions'.)
•If correct positioning of the tracheostomy tube is uncertain, flexible bronchoscopy is employed to verify its position within the trachea before initiating ventilation.
Patient-specific considerations — Open tracheostomy is typically performed for one of the following situations (see "Tracheostomy in adults: Techniques and intraoperative complications", section on 'Selecting percutaneous versus operative'):
●Elective tracheostomy for anticipated airway compromise at or above the vocal cords due to existing tracheal pathology or as an expected result of planned surgery.
●Emergency tracheostomy for critical airway occlusion at or above the vocal cords.
●Elective tracheostomy to facilitate airway management in a currently intubated patient with likely need for prolonged controlled ventilation [2], including those with novel coronavirus disease 2019 (COVID-19). (See "Anesthesia for tracheal surgery: General considerations", section on 'Tracheal surgery in COVID-19 patients'.)
Need for prolonged intubation — Patients who are currently intubated and ventilator-dependent typically have respiratory insufficiency and are critically ill. Elective tracheostomy should be postponed if the patient is hemodynamically unstable and cannot be safely transported from the intensive care unit (ICU) to the operating room.
Anesthetic management involves continuing or adjusting baseline intravenous (IV) sedative-analgesic agents and/or adding additional anesthetic agents to maintain sedation/anesthesia. It may also be necessary to adjust baseline vasoactive infusions to maintain hemodynamic stability. For example, during ETT removal and tracheostomy tube insertion, augmentation of anesthetic depth may beneficially blunt hemodynamic responses to this intense noxious stimulation of the airway. Doses of IV anesthetic agents may be used, or addition of an inhalation anesthetic is a reasonable option during certain portions of the procedure. However, when the trachea is temporarily open, escape of volatile anesthetic agent and consequent pollution of the operating room atmosphere will occur.
Although administration of a neuromuscular blocking agent (NMBA) is common and typically useful, this is not always necessary and may be unwise if there is concern regarding patient-related surgical or anatomic challenges.
Anticipated airway compromise above the vocal cords — Selection of local or general anesthesia for planned tracheostomy due to existing or impending upper airway compromise is based on the likelihood that the airway would be lost if the patient is sedated or anesthetized. (See "Anesthesia for tracheal surgery: General considerations", section on 'Selection of anesthetic technique'.)
●If general anesthesia is selected, an ETT may be passed through the cords, either directly or through a supraglottic airway (ie, laryngeal mask airway [LMA]). If upper airway compromise allows for ventilation from above the cords, the ETT can be inserted after induction, then the surgeon may proceed with the tracheostomy with the precautions noted above. (See 'General considerations' above.)
●If a general anesthetic is to be avoided and the patient will remain awake then the airway and neck must be made insensate. Use local anesthetic to topicalize the airway with optional sedation. The goal is a comfortable patient who is sedated and not moving but breathing spontaneously. (See "Anesthesia for tracheal surgery: General considerations", section on 'Use of local anesthetic for selected procedures'.)
●Oxygen may be delivered via a facemask or nasal cannula as needed. With oxygen delivery via such open systems, use of the ESU is avoided if possible. However, if the surgeon will use an ESU and the patient needs supplemental oxygen, attach the facemask or nasal tubing to a 5 mm ETT connector attached to the Y-piece of the breathing circuit of the anesthesia machine so that a precise preset blending of oxygen and air at a FiO2 <30 percent can be delivered (the lower the better). Notably, several minutes may be required for FeO2 to be reduced to <30 percent, as noted above [1]. (See 'General considerations' above and "Fire safety in the operating room", section on 'Management of open oxygen delivery systems'.)
Emergency tracheostomy for critical airway occlusion — Emergency surgical entry directly into the subglottic larynx (ie, cricothyrotomy) may be necessary to treat critical airway occlusion. Jet ventilator equipment should be immediately available for any patient with critical tracheal stenosis especially those that are unstable. (See "Anesthesia for tracheal surgery: General considerations", section on 'Jet ventilation'.)
Indications and technical aspects for this procedure are discussed separately. (See "Emergency cricothyrotomy (cricothyroidotomy)".)
Percutaneous "mini" tracheostomy — A percutaneous tracheostomy is typically performed in the ICU between the second and fourth tracheal rings, with sequential dilations over a guide wire to allow for transcutaneous placement of a small diameter tracheostomy tube [3,4]. A modified technique employing a tube exchanger has been employed [5]. Typically, this procedure is performed under local anesthesia, often at the bedside. (See "Anesthesia for tracheal surgery: General considerations", section on 'Use of local anesthetic for selected procedures'.)
Indications for percutaneous tracheostomy are presented separately. (See "Tracheostomy: Rationale, indications, and contraindications".)
Considerations for patients with a previous tracheostomy — Patients who have a recent or long-term tracheostomy may present for a variety of surgical or diagnostic procedures requiring general anesthesia or sedation with monitored anesthesia care (MAC) [2,6]. Preoperative multidisciplinary planning for airway management is necessary. This may include use of a tracheostomy tube (T-tube) with an appropriately sized endotracheal tube (ETT) connector or replacing the T-tube with a standard or pediatric ETT [2,6].
BRONCHOSCOPIC EVALUATION BEFORE TRACHEAL SURGERY
Flexible bronchoscopy — Before beginning some elective tracheal surgical procedures, such as stent placement or open repair or reconstruction, the surgeon usually inspects the glottis and trachea via a flexible bronchoscope. This preprocedural examination is useful to define current anatomy and pathology, confirm that the planned surgical procedure is appropriate, and rule out the presence of a new acute process that could be improved with therapy. In some cases, a decision to reschedule elective surgery is appropriate.
Depending on the goal of the bronchoscopic examination and patient-specific factors, the anesthetic technique may involve local anesthetic topicalization of the vocal cords and trachea with optional sedation, rather than general anesthesia. (See "Anesthesia for adult bronchoscopy", section on 'Topical airway anesthesia with sedation'.)
If a general anesthetic technique is selected, support of ventilation will be necessary. The flexible bronchoscope may be inserted through a supraglottic airway (ie, laryngeal mask airway [LMA]) device or endotracheal tube (ETT) that has an inner diameter (ID) that is ideally ≥7.5 mm. Adequate ventilation is usually achieved by ventilating around the scope after its passage through the LMA or ETT. The breathing circuit from the anesthesia machine is attached to a side port of a bronchoscope adapter (picture 1). (See "Anesthesia for adult bronchoscopy", section on 'Airway control'.)
Either an inhalation anesthetic technique or total intravenous anesthesia (TIVA) may be employed to produce general anesthesia during flexible bronchoscopy. We typically select a TIVA technique if significant suctioning of the trachea is anticipated since suctioning causes interruptions in inhalation anesthetic delivery. Patient immobility and absent cough reflex may be achieved with or without administration of a neuromuscular blocking agent (NMBA). Details regarding anesthetic techniques and agents are discussed separately. (See "Anesthesia for adult bronchoscopy", section on 'Anesthetic techniques'.)
Rigid bronchoscopy — Rigid bronchoscopy may be employed in selected patients to accomplish airway evaluation, dilation, or placement of a tracheal T-tube or stent. The rigid bronchoscope is a straight metal tube available in a range of calibers with a beveled distal end that is inserted into the trachea through the mouth (or tracheostomy stoma) in order to visualize the trachea, and, in some cases, the mainstem bronchi.
Typically, deep general anesthesia is necessary during rigid bronchoscopy due to noxious airway stimulation and extreme discomfort. Details regarding specific anesthetic techniques and agents used during rigid bronchoscopy are discussed separately. (See "Anesthesia for adult bronchoscopy", section on 'General anesthesia for rigid bronchoscopy'.)
Advantages and disadvantages of different ventilation methods that may be employed during rigid bronchoscopy are discussed separately (see "Anesthesia for adult bronchoscopy", section on 'Ventilation techniques'). These include:
●Standard positive pressure ventilation (PPV) – PPV is accomplished by attaching the anesthesia circuit to the side port of the rigid bronchoscope (picture 2). Ventilation is typically controlled by hand to accommodate the bronchoscopist's need for periods of apnea. (See "Anesthesia for adult bronchoscopy", section on 'Positive pressure ventilation'.)
In patients with tracheal narrowing, conditions for ventilation may vary. For example, a small-caliber rigid bronchoscope may be passed through a tracheostomy stoma, and ventilation is accomplished through the side-port of the bronchoscope. The tight fit of the rigid bronchoscope against the narrowed segment of the trachea allows PPV. However, leakage of gases around the bronchoscope occurs when it is not fully engaged with the stricture, or as the stenotic tracheal segment becomes progressively dilated. It may then be necessary to administer high flows of oxygen to compensate for lost airway gases, with continuous monitoring of pulse oximetry and observation of chest rising to ensure adequacy of PPV and oxygenation [7]. Since gas flows are high in this setting, capnography is not a useful monitor.
●Jet ventilation (JV) – JV is accomplished via a purpose-built port that has a Luer-Lock connector for the JV tubing (picture 3 and picture 4). (See "Anesthesia for adult bronchoscopy", section on 'Jet ventilation'.)
●Intermittent ventilation with an ETT – If necessary to ensure adequacy of ventilation, the bronchoscope may be intermittently removed and replaced by an ETT. In such cases, a flexible kink-resistant ETT (eg, a wire-reinforced "armored" ETT) is preferred (picture 5). (See "Anesthesia for tracheal surgery: General considerations", section on 'Endotracheal tube selection'.)
We usually select a TIVA technique to maintain general anesthesia, including administration of a NMBA to induce complete muscle relaxation. This prevents patient movement and facilitates exposure of the glottis for the bronchoscopist. We typically avoid inhalation anesthesia with a volatile anesthetic agent since leakage of anesthetic gases around and through the bronchoscope will contaminate the operating room during interventions performed by the bronchoscopist. Furthermore, measurements of the end-tidal anesthetic agent will be inaccurate. In addition, if JV is employed, TIVA is the only anesthetic choice since inhalation anesthetics cannot be administered via a JV system. (See "Anesthesia for adult bronchoscopy", section on 'Total intravenous anesthesia'.)
Occasionally, we may use an inhalation anesthetic technique with sevoflurane if the surgeon requests a period of spontaneous negative pressure ventilation for observation of dynamic pathology such as movement of the membranous back wall of the trachea with respiratory variations that occur in patients with tracheomalacia. (See "Anesthesia for adult bronchoscopy", section on 'Inhalation anesthesia'.)
INSERTION OF AN ENDOTRACHEAL STENT — An endotracheal stent provides tracheal support to improve or maintain airway patency in patients with a tracheal mass, stenosis, or collapse [8]. Urgent or emergency stenting may be employed to treat critical tracheal stenosis. In such cases, ventilation strategies are individualized depending on the location (and cause) of tracheal narrowing [9]. Less commonly, placement of a stent may be necessary to occlude a tracheal laceration or fistula.
Orally placed tubes are straight and situated distal to the vocal cords. In some cases, the distal end bifurcates to travel for a distance down the mainstem bronchi. Stents placed via a tracheal stoma are "T" shaped, with a limb extending through the tracheostomy site and the proximal and distal limbs positioned in the trachea. These stents may be straight or bifurcated at the end (picture 6 and picture 7) [8]. (See "Airway stents".)
The stent or T-tube is deployed through a rigid or flexible bronchoscope inserted and/or forceps via a transoral or stomal route (see 'Bronchoscopic evaluation before tracheal surgery' above) [8]. If placement is through a mature stoma into an intact trachea, the airway will be reliably accessible throughout the procedure.
●Local anesthesia – In selected cases it is possible to place a stent via a flexible bronchoscope with local anesthetic applied to the airway plus optional sedation. Examples include silicone or expandable metal stents that can be gently and quickly deployed into position and do not need removal for sizing (table 1) [10]. (See "Anesthesia for adult bronchoscopy", section on 'Topical airway anesthesia with sedation'.)
●General anesthesia – Deep general anesthesia is usually necessary for stent insertion, particularly if the device is deployed via a rigid bronchoscope (see 'Rigid bronchoscopy' above). In one randomized study of 64 patients undergoing airway stenting, controlled ventilation with administration of a neuromuscular blocking agent (NMBA) resulted in a lower incidence of desaturation events (ie, percutaneous oxygen saturation [SpO2] <95 percent) compared with allowing spontaneous respiration (10 versus 75 percent) [11].
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 (see "Anesthesia for tracheal surgery: General considerations", section on 'Intermittent ventilation'). If transoral ventilation can be used, we employ an oxygen mask, supraglottic airway (ie, laryngeal mask airway [LMA]), 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 a 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 5). (See "Anesthesia for tracheal surgery: General considerations", section on 'Endotracheal tube selection'.)
We prefer a total intravenous anesthesia (TIVA) technique since delivery and end-tidal measurements of inhalation anesthetic gases are unreliable during these periods, and we also use a neuromuscular blocking agent (NMBA) to prevent patient movement. (See "Anesthesia for tracheal surgery: General considerations", section on 'Maintenance'.)
Before extubation, possible administration of dexamethasone 8 to 10 mg to reduce airway and vocal cord swelling is discussed with the surgeon. We avoid administration of any long-acting opioid since insertion of an endotracheal stent or T-tube produces little or no postoperative pain, and to avoid harm from oversedation when airway patency may be tenuous in the postoperative period (see "Anesthesia for tracheal surgery: General considerations", section on 'Pain management'). For example, airway obstruction may be caused by accumulation of secretions or clot, or by a dynamic tracheal lesion that allows a stent to drift into malposition. Continued close observation is necessary during and after emergence to ensure airway patency. (See "Anesthesia for tracheal surgery: General considerations", section on 'Emergence and extubation'.)
Some patients cough repeatedly postemergence with their primary complaint being the feeling of a foreign body in the trachea. If the patient's airway is patent, low doses of a short-acting opioid (eg, fentanyl 25 to 50 mcg) may be judiciously administered to blunt the cough reflex.
OPEN REPAIR OR STENT OCCLUSION OF A TRACHEOESOPHAGEAL FISTULA — Tracheoesophageal fistulae (TEF) are patent connections between the respiratory and upper gastrointestinal (GI) tract (picture 8). 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). TEFs due to motor vehicle accidents with a crush injury to the chest are typically located at the carina. Other etiologies may occur anywhere along the trachea. (See "Tracheo- and broncho-esophageal fistulas in adults".)
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 9). Tracheal stents are positioned via flexible or rigid bronchoscopy, and may be combined with an esophageal "kissing stent" placed via esophagoscopy (picture 10). (See 'Bronchoscopic evaluation before tracheal surgery' above and "Anesthesia for esophagectomy and other esophageal surgery", section on 'Repair of tracheoesophageal fistula'.)
For open repair, a transverse low "collar" incision that may be extended via a partial sternotomy is typically accomplished in the supine position. However, a right thoracotomy in the left lateral decubitus position may be selected for a distally located TEF. A long endotracheal tube (ETT) may be necessary for a distally located TEF (picture 11).
Preoperative preparation
Preoperative assessment and planning — General anesthesia is necessary for open repair of TEF or for stent occlusion via a rigid bronchoscope. As noted above, when flexible bronchoscopy is employed, stent placement may be possible using local anesthesia plus sedation in selected patients. (See 'Insertion of an endotracheal stent' above.)
In addition to standard assessment and planning for tracheal surgery, the following preoperative considerations are important (see "Anesthesia for tracheal surgery: General considerations", section on 'Preoperative assessment and planning'):
●Confirm optimal medical condition, particularly whether treatment of pulmonary infection and nutritional status are adequate.
●Confirm administration of usual medications on the morning of surgery, particularly proton pump inhibitors and acid suppression therapy.
●Understand the patient's anatomy (precise location and size and patency of the lesion) and confirm the surgical approach and planned interventional sequence (eg, positioning, use of flexible or rigid bronchoscopy, location of incision[s]).
●Achieve consensus during the preoperative team briefing regarding techniques for anesthetic induction, endotracheal intubation and positioning of the tip positioning, and maintenance of oxygenation and ventilation. (See "Anesthesia for tracheal surgery: General considerations", section on 'Key points for surgical briefings'.)
●If a right thoracotomy is planned, insertion of a thoracic epidural (TEA) or paravertebral block (PVB) catheter is typically accomplished before induction of general anesthesia. (See "Anesthesia for tracheal surgery: General considerations", section on 'Planning for postoperative analgesia'.)
Operating room setup — In addition to standard equipment for airway management, the following specific equipment should be available (see "Anesthesia for tracheal surgery: General considerations", section on 'Operating room setup'):
●Flexible bronchoscopes in both adult and pediatric sizes immediately available in the operating room throughout the surgical procedure.
●Dedicated suction for the bronchoscope and a second setup with a Yankauer suction tip available at the head of the bed.
●An assortment of regular, extra-long, and a wire-reinforced "armored" ETTs in all sizes from 7.0 mm ID down to the smallest available cuffed sizes (picture 5). If the fistula is close to the carina or involves a bronchus, a long ETT, double-lumen endotracheal tube (DLT), and/or a bronchial blocker may be needed (picture 11). The selected tube will be advanced over the flexible bronchoscope beyond the fistula into the opposite bronchus so that one lung ventilation (OLV) can be initiated. Then, the nonventilated lung can be isolated from the fistula by a bronchial blocker, if necessary. (See "Anesthesia for tracheal surgery: General considerations", section on 'Endotracheal tube selection' and "Lung isolation techniques".)
●An assortment of supraglottic airway devices (ie, laryngeal mask airway [LMA]) may be used as another option to facilitate fiberoptic bronchoscopic examination and tracheal suctioning. (See "Anesthesia for tracheal surgery: General considerations", section on 'Supraglottic airway devices'.)
Induction and initial airway management — Patients with TEF are at high risk for pulmonary aspiration of gastric contents that have seeped through the fistula tract. Applying cricoid pressure during induction is not protective. The following strategies may be beneficial:
●Preinduction strategies are employed to minimize gastric insufflation and risk for soilage of the trachea via the fistula tract include:
•Elevation of the head of the bed to a 30 degree angle to both reduce the risk and improve the functional residual capacity of lungs that may be chronically damaged by pulmonary aspiration.
•Preoxygenation with 100 percent oxygen to increase oxygen reserve and provide additional time to secure the airway before positive pressure ventilation (PPV) is initiated [12]. (See "Rapid sequence induction and intubation (RSII) for anesthesia", section on 'Preoxygenation'.)
•Preinduction stomach evacuation via an esophagoscope after numbing the oropharynx. However, blind instrumentation of the esophagus is avoided. Typically, the surgeon will use an esophagoscope to evacuate gastric contents under direct visualization, and, in some cases, may position a nasogastric or orogastric tube for later evacuation of stomach contents.
●Induction strategies emphasize avoiding blind intubation as this may result in inadvertently traversing the fistula tract and intubating the esophagus or mediastinum. Thus, intubation and ETT positioning are always accomplished with fiberoptic bronchoscopic guidance. Isolation of the TEF while avoiding soiling of the trachea with gastric contents may be accomplished by:
•Awake intubation of a spontaneously breathing patient after topical anesthesia and/or nerve blocks, as described separately (see "Flexible scope intubation for anesthesia", section on 'Topical anesthesia'). However, the airway must be exceptionally well anesthetized during intubation since coughing increases abdominal and epigastric tone, thereby increasing risk of spillage of gastric contents into the trachea and copious tracheal secretions may present a topicalizing challenge. General anesthesia is induced only after the ETT has been properly positioned.
•Induction of general anesthesia with efficient endotracheal intubation and avoidance of PPV until the fistula is isolated by placement of the ETT cuff beyond the TEF (see "Anesthesia for tracheal surgery: General considerations", section on 'Induction and airway management'). Specific techniques for induction of general anesthesia and placement and positioning of the ETT via a flexible bronchoscope include:
-Rapid sequence induction and intubation (RSII). 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 [13,14]. We prefer RSII if it is likely that the airway can be easily secured in a patient with unambiguous airway anatomy. (See "Rapid sequence induction and intubation (RSII) for anesthesia" and "Rapid sequence induction and intubation (RSII) for anesthesia", section on 'Defasciculation'.)
-Inhalation induction to avoid PPV by maintaining negative pressure spontaneous breathing until the fistula has been isolated by a properly positioned ETT. Potentially difficult airway anatomy should be anticipated (eg, patients with severe tracheal inflammation or copious secretions). This can create challenges in distinguishing the trachea from the fistula tract or esophagus during bronchoscopic examination. For such patients, an inhalation induction or awake intubation is a safer choice than RSII since these techniques allow the patient to continue ventilating during the additional time that may be required to adequately visualize anatomical structures.
-Awake intubation after numbing the airway with topically applied local anesthetic or use of airway nerve blocks, with optional sedation when appropriate. Notably, patients with copious secretions may interfere with adequacy of topical anesthetic techniques.
●Verification of correct ETT position ensures 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. In some cases, the surgeon may opt to perform flexible bronchoscopic inspection of the fistula while the patient is awake or may request that an LMA be inserted immediately after induction of general anesthesia to allow a quick inspection before insertion of the ETT (which may cover up the pathology). In such cases, the ETT can subsequently be inserted over the flexible bronchoscope for proper positioning.
●Patients with a TEF near the carina require special management. Either a DLT or a long single lumen tube may be employed. If it is not possible to inflate the tracheal cuff of the DLT due to proximity to the TEF, a bronchial blocker is used to isolate the nonventilated lung from the TEF. (See "Anesthesia for tracheal surgery: General considerations", section on 'Endotracheal tube selection' and "Lung isolation techniques".)
●PPV is avoided until the fistula has been isolated by a properly positioned ETT, in order to prevent gastric insufflation and pressurization. If the trachea is grossly soiled, the flexible bronchoscope can be used for suctioning and cleaning the distal airways prior to initiating PPV.
●Initiation of controlled PPV is with low pressure settings. Start at 10 to 15 cm H2O for a target tidal volume (TV) of 4 to 6 mL/kg using either one or two lungs. Typically, the fraction of inspired oxygen (FiO2) is set at 100 percent initially, then reduced to the lowest level that maintains adequate oxygen saturation (measured with pulse oximetry). Controlled ventilation and oxygenation may be facilitated by administration of a NMBA and/or lung recruitment maneuvers. Further details are available in separate topics. (See "Anesthesia for tracheal surgery: General considerations", section on 'Standard positive pressure ventilation' and "One lung ventilation: General principles", section on 'Lung-protective ventilation strategies'.)
Maintenance and intraoperative airway management — After general anesthesia has been induced and the airway has been secured, the surgeon will reevaluate airway and esophageal pathology using both bronchoscopy and esophageal endoscopy. In some cases, the surgeon may opt to place an esophageal stent that at least partially isolates the TEF. Repair of the esophagus and trachea (or stent placement) is subsequently completed after the distal airway has been suctioned and cleaned via a flexible bronchoscope and after maneuvers to facilitate alveolar recruitment.
If the ETT is positioned beyond the fistula, it is pulled back intermittently during the surgical repair in order to visualize and access the TEF. PPV is avoided whenever the fistula is exposed; instead, intermittent ventilation is employed during these periods (see "Anesthesia for tracheal surgery: General considerations", section on 'Intermittent ventilation').
Since inhalation anesthetic delivery and end-tidal measurements of exhaled concentration are unreliable during intermittent ventilation, we employ a TIVA technique to ensure maintenance of adequate anesthetic depth. (See "Anesthesia for tracheal surgery: General considerations", section on 'Maintenance' and "Maintenance of general anesthesia: Overview", section on 'Total intravenous anesthesia'.)
Extubation and recovery
●Extubation – Typically, tracheal extubation is planned at the end of the surgical procedure in the operating room [15,16]. The surgeon must be present.
Just before emergence, the surgeon may inspect and further clean the airway with a flexible bronchoscope inserted via the existing ETT or through an LMA that is placed at the end of the case. If an LMA is selected, bronchoscopic examination of the vocal cords can address any concerns regarding vocal cord swelling or injury to the recurrent laryngeal nerve. (See "Respiratory problems in the post-anesthesia care unit (PACU)", section on 'Vocal cord paralysis'.)
Other prerequisites for extubation are described separately. (See "Anesthesia for tracheal surgery: General considerations", section on 'Emergence and extubation'.)
●Recovery – Following extubation, positive pressure airway support is used judiciously after any tracheal repair. Although reintubation is avoided if possible, this is accomplished over a flexible bronchoscope using a small diameter ETT when necessary.
Patients undergoing TEF repair are transported to the intensive care unit (ICU) for postoperative observation and management, as discussed separately. (See "Anesthesia for tracheal surgery: General considerations".)
Postoperative pain after isolated stent insertion or a transverse cervical incision is typically minimal. (See "Anesthesia for tracheal surgery: General considerations", section on 'Pain management'.)
TRACHEAL RESECTION AND RECONSTRUCTION — Tracheal pathology requiring tracheal resection and reconstruction may be malignant or benign. The surgical approach depends on lesion location [17]:
●Upper or midtracheal lesions such as postintubation injuries are typically approached through a cervical transverse collar incision.
●Lower tracheal or carinal lesions, as well as hilar or carinal releases are typically approached via either a sternal split or a right thoracotomy.
Preoperative assessment and preparation — Preoperative preparations are generally similar to those for repair of a tracheoesophageal fistula (TEF) (see 'Preoperative assessment and planning' above). Additional considerations include [17] (see "Anesthesia for tracheal surgery: General considerations", section on 'Preoperative assessment and planning'):
●Since tracheal pathology may be dynamic, reevaluation just before surgery is particularly important to check for changes in status, and to select the most appropriate induction and airway management techniques.
●The patient is informed that there will be retention "chin" stitches running from their chin to upper chest to hold their head and neck in flexion during the postoperative period (to offload the trachea tension), and that they should not pull these stitches by attempting to extend the head and neck when they awaken from anesthesia.
●An intra-arterial catheter is inserted in all patients undergoing tracheal resection and reconstruction; this is particularly important for postoperative management.
●Intravascular access via two reliable peripheral or other IV catheters is preferred, since the arms will be tucked and inaccessible. (See "Anesthesia for tracheal surgery: General considerations", section on 'Monitoring'.)
Induction and initial airway management — Anesthetic induction requires careful planning [17]. (See "Anesthesia for tracheal surgery: General considerations", section on 'Induction and airway management'.)
An endoscopic airway evaluation with flexible or rigid bronchoscopy, or both, is typically performed before surgical incision to finalize the to finalize the operative plan [8]. A flexible bronchoscope may be inserted transorally with the patient awake, or through an endotracheal tube (ETT) or a supraglottic airway (ie, laryngeal mask airway [LMA]) with the patient asleep (see 'Flexible bronchoscopy' above). Some surgeons may elect to insert a rigid bronchoscope immediately after anesthetic induction, but before ETT intubation (see 'Rigid bronchoscopy' above). Furthermore, if the patient has critical airway stenosis, the surgeon may need to dilate the trachea using the rigid bronchoscope to allow subsequent passage of a 5.5 or 6.0 mm cuffed ETT though the stenotic area.
An LMA may be considered for use as the primary airway until cross-table or jet ventilation (JV) is established [17-20] (see "Anesthesia for tracheal surgery: General considerations", section on 'Supraglottic airway devices' and 'Maintenance and intraoperative airway management' below), especially if the patient has a friable mid- to proximally-located subglottic stenosis. The LMA is placed during induction of general anesthesia and used until the trachea is resected distal to the pathology. By avoiding traversing the tracheal pathology with an ETT, risks for mechanical trauma, swelling, bleeding, or tumor fragmentation, with resultant airway occlusion, are minimized. An LMA may also serve as a rescue airway if the trachea cannot be intubated after anesthetic induction agents are administered [9,20]. Potential disadvantages of LMA use include managing an airway that is not secured and potential difficulty in performing an anastomotic leak test (at 20 cm H2O and maybe higher) using a brief Valsalva maneuver after completion of the tracheal reconstruction [17].
Maintenance and intraoperative airway management — We typically select a total intravenous anesthesia (TIVA) technique (eg, with propofol and remifentanil titrated to maintain adequate anesthetic depth) and add a nondepolarizing NMBA to maintain anesthesia [8,17]. Intermittent manipulation of the airway during surgery is highly stimulating, necessitating careful titration of the anesthetic agents used for a TIVA technique. (See "Anesthesia for tracheal surgery: General considerations", section on 'Maintenance' and "Maintenance of general anesthesia: Overview", section on 'Total intravenous anesthesia'.)
Once the trachea is exposed, the FiO2 should be reduced to <0.3 if any ignition source (eg, an electrosurgery unit [ESU]) is being used (see "Fire safety in the operating room", section on 'Special precautions during airway surgery'). Immediately prior to transection of the trachea, all ESU devices must be handed off the surgical field. This allows administration of 100 percent oxygen for preoxygenation. When the trachea is transected, the oral ETT is retracted so that the tip is just proximal to the transected portion of the trachea. The surgeon then directly intubates the main conducting airway distal to the affected tracheal area and directly connects the ETT (typically a wire-reinforced ETT (picture 5)), connected to sterile breathing circuit tubing (or jet ventilator tubing) on the surgical field [18]. The proximal end of such tubing is passed over the surgical drapes to non-sterile extension tubing, which is immediately connected to the anesthesia machine or jet ventilator by the anesthesiologist to establish cross-field ventilation. Subsequent ventilation is accomplished with well-timed hand-delivered breaths via the distal tracheal ETT, alternating with periods of intermittent ventilation (see "Anesthesia for tracheal surgery: General considerations", section on 'Intermittent ventilation'), or with JV (see "Anesthesia for tracheal surgery: General considerations", section on 'Jet ventilation'). This cross-field ventilation technique ensures continued oxygenation and ventilation, potentially for a prolonged period of time, while the trachea is being reconstructed. An alternative technique to achieve JV is by advancing the jet ventilator tubing through the oral airway (ie, an LMA or ETT) or by retrograde passage of the proximal end of the jet ventilator tubing from the surgical field up into the oropharynx (or the lumen of an LMA), thereby allowing the anesthesiologist to grasp and connect it to a jet ventilator, while the surgeon places the distal tip of the tubing into the distal trachea (picture 12) [20].
After reconstruction of the trachea, the oral ETT is carefully readvanced through the new anastomosis. Circumferential tracheal sutures are then tightened so that controlled positive pressure ventilation (PPV) may be employed without significant leaking. Typically, an anastomotic leak test is performed. The repair is completed with the patient's head flexed and supported on blankets to reduce tension on the fresh tracheal suture lines. (See "Anesthesia for tracheal surgery: General considerations", section on 'Key points for surgical briefings'.)
Extubation and recovery — After completion of the repair, the surgeon often repeats flexible bronchoscopy to inspect and clean the upper airway and trachea, either via the retracted ETT or through an LMA that is inserted shortly before emergence.
Most patients undergoing tracheal resection and reconstruction are then allowed to emerge from general anesthesia with the ETT or LMA in place, and are extubated in the operating room [8,17]. In the rare case that reintubation becomes necessary while the patient is still in the operating room or in the immediate postoperative period, a small ETT is selected and placed over a fiberoptic bronchoscope [17]. Compared with endotracheal extubation, use of an LMA may cause less coughing and mechanical stress on the freshly sutured airway during emergence [17,20].
Patients undergoing tracheal resection and reconstruction are transported to the intensive care unit (ICU) for postoperative observation and management. Other aspects of extubation and recovery are similar to those after other types of major tracheal surgery, as discussed above and in a separate topic. (See 'Extubation and recovery' above and "Anesthesia for tracheal surgery: General considerations", section on 'Emergence and extubation'.)
SUMMARY AND RECOMMENDATIONS
●General considerations – General considerations for anesthetic management of tracheal surgery including preoperative assessment and planning; anesthetic techniques; options for oxygenation and ventilation; induction, maintenance, and emergence from general anesthesia; and management of pain and other issues in the immediate postoperative period, as discussed in a separate topic. (See "Anesthesia for tracheal surgery: General considerations".)
Specific anesthetic considerations and techniques are procedure-dependent, as noted below:
●Tracheostomy (see 'Tracheostomy' above)
•Open tracheostomy (see 'Open tracheostomy' above)
•Percutaneous tracheostomy (see 'Percutaneous "mini" tracheostomy' above)
•Considerations with a previous tracheostomy (see 'Considerations for patients with a previous tracheostomy' above)
●Bronchoscopic evaluation – (picture 1 and picture 2 and picture 3 and picture 4) (see 'Flexible bronchoscopy' above and 'Rigid bronchoscopy' above and "Anesthesia for adult bronchoscopy")
●Insertion of an endotracheal stent – (table 1 and picture 6 and picture 7) (see 'Insertion of an endotracheal stent' above)
●Open repair or stent occlusion of a tracheoesophageal fistula (TEF) – (picture 8 and picture 9 and picture 10) (see 'Open repair or stent occlusion of a tracheoesophageal fistula' above)
●Tracheal resection and reconstruction – Just before resection, the surgeon directly intubates the main conducting airway distal to the affected tracheal area and directly connects a wire-reinforced endotracheal tube (ETT) (picture 5). During resection, ventilation is accomplished with hand-delivered breaths via the distal tracheal ETT alternating with periods of intermittent ventilation, or with jet ventilation via a catheter passing through the transected trachea (picture 12). (See 'Tracheal resection and reconstruction' above.)
