Otolaryngology—Head and Neck Surgery



Otolaryngology—Head and Neck Surgery


Michael J. Kaplan MD (Head & Neck Surgery)1

Edward J. Damrose MD (Laryngology)1

Nikolas H. Blevins MD (Otology & Neurotology)1

Robert K. Jackler MD (Otology & Neurotology)1

Peter H. Hwang MD (Endoscopic Sinus Surgery)1

Sarmela T. Sunder MD (Endoscopic Sinus Surgery)1

Sam P. Most MD (Nasal Surgery)1

Willard E. Fee Jr. MD (Head & Neck Surgery)1

Robert W. Riley DDS, MD (Sleep-disordered breathing)1

Nelson B. Powell MD (Sleep-disordered breathing)1

Donald M. Sesso DO (Sleep-disordered breathing)1

Vladimir Nekhendzy MD (All topics)2

Brett L. Miller (Sleep-disordered breathing)2

Michael W. Champeau MD (Sleep-disordered breathing)2


1SURGEONS

2ANESTHESIOLOGISTS




INTRODUCTION—SURGEON’S PERSPECTIVE

Interdisciplinary cooperation is nowhere more critical than where the priority of airway maintenance is confronted both with abnormalities in the airway and with adjacent surgical goals. An anesthesiologist versed both in the management of the difficult airway and an ability to accurately anticipate the issues confronting the surgeon is critical. Similarly, a communicative surgeon fully aware of the problems the anesthesiologist is likely to encounter is critical to minimizing complications. Important issues that require mutual understanding include:



  • Airway management: anesthesia induction, endotracheal tube size, head range of motion with shared airway space, a well-secured ETT, postop airway edema, and smooth emergence from anesthesia


  • Muscle relaxation, patient immobility, patient positioning


  • Deliberate relative hypotensive anesthesia and management of bradycardia


  • Antiemetics and pain management postop


  • Patient population considerations: frequent cardiac and pulmonary issues associated with older patients, especially with alcohol and tobacco use; degenerative c-spine issues; and prior irradiation affecting neck mobility.

Airway management: An initially compromised airway is not uncommon in many otolaryngology head and neck procedures. Many others may develop airway loss at induction or if premature extubation occurs. Communication between the surgeon and anesthesiologist is essential, as is a discussion of a plan and backup plan should an emergency arise. Availability of a sliding Jackson scope and tracheotomy equipment, as well as plans for fiberoptic intubation, awake intubation, or retrograde intubation, should be discussed as indicated.

For procedures within the airway, an endotracheal tube no larger than 6 mm should be adequate and will reduce postop airway edema. An armored tube is helpful when the surgical procedure is intraoral and the tube may be compressed. A nasotracheal intubation should be discussed as an alternative in this situation. If laser surgery is planned, maintaining the FiO2 at < 0.3 is indicated. If fiberoptic bronchoscopy is planned, then a 7.0- or 7.5-mm ETT will facilitate passage of the bronchoscope through the ETT, after which for a longer case, changing to a smaller tube may be warranted.

As the patient is generally turned 90° or 180° away from the anesthesiologist, a very secure airway is important. If the surgeon needs access in the mouth, securing the tube via a wire to several teeth may work better than tape.

Muscle relaxation and patient positioning: Avoidance of muscle relaxation is important if a motor nerve, such as the facial nerve, is to be dissected. Muscle relaxation is important, on the other hand, in esophagoscopy and tongue surgery. Communicate and coordinate timing of drug administration. Frequently the surgeon will need to turn the patient’s head during surgery. Anticipating this movement when initially securing the endotracheal tube and its connections will prevent disconnection. In neck surgery, the neck is often rotated away from the surgeon; overrotation presents the risk of brachial plexus stretch injuries. If a radial free flap is anticipated, then positioning of the arm as well as rotation of the head should be carefully coordinated to avoid injury while still providing needed access and a secure airway.

Deliberate relative hypotensive anesthesia, to a SBP of <100 mmHg, depending on individual patient’s needs, is often a boon to the surgeon operating in the highly vascular fields of the head and neck, or operating with a microscope. For selected cases the patient also will have had preop embolization of a tumor and its blood supply (e.g., angiofibromas and skull base paragangliomas). Bradycardia may occur if the surgeon operates near the vagus nerve or carotid bifurcation. If this occurs, it is usually sufficient for the anesthesiologist to communicate this and the surgeon can desist for a period of time. Occasionally topical or locally injected anesthetics will be necessary.


INTRODUCTION—ANESTHESIOLOGIST’S PERSPECTIVE


PATIENT POPULATION

Many ENT patients are smokers and elderly, and have ↑ incidence of CAD, HTN, chronic renal insufficiency, and COPD. Careful H&P must be performed to ensure that the patient’s functional status is optimized. Chronic cigarette smoking and alcohol use also cause an induction of cytochrome P450 multi-enzyme system →↑ opioids and ↑ NMB requirements.









Table 3-1. Predictors of Difficult Face Mask Ventilation

















Age > 57 y.o.


Body Mass Index ≥ 30 kg/m2


Beard


Snoring or OSA


Lack of teeth


Mallampati III or IV


Limited mandibular protrusion









Table 3-2. Predictors of Impossible Mask Ventilation













Male


Beard


Obstructive sleep apnea (moderate to severe, requiring PAP treatment)


Mallampati III or IV


H/o neck radiation



AIRWAY

ENT patients often present with H&P findings associated with a difficult airway including: (1) anatomic characteristics (e.g., ↓ C-spine ROM, large tongue, receding jaw, etc.); (2) Hx of stridor and hoarseness (airway narrowing and possible vocal cord (VC) dysfunction); (3) previous Hx of neck surgery, trauma, or XRT (↓ compliance of the tissues, ↓ neck ROM, ↓ mouth opening); (4) previous Hx of difficult intubation, and (5) infections (e.g., epiglottitis, retropharyngeal abscess, Ludwig’s angina).

Meticulous examination of the airway must be performed, and there should be a low threshold for an awake intubation if the airway is questionable. The awake vs. asleep approach to tracheal intubation should be guided by the presence of predictors of difficult or impossible mask ventilation, and their association with difficult intubation (DI) (Tables 3-1 and 3-2).

If intubation difficulty is anticipated, but a conventional DL after induction of GA is nevertheless chosen, at least two clearly defined backup airway management plans should be in place. Video laryngoscopy (e.g., Glidescope) will often improve airway visualization, and the LMA-Fastrach™ provides rescue ventilation with a 95-100% success rate in difficult airway situations. If a conventional DL was chosen as a first approach, the patient’s head positioning should be optimized and simple intubating aids (e.g., stylets, gum elastic bougie) as well as the ETTs of different sizes made readily available. The number of DL intubation attempts should be limited to two; repeated intubating attempts are associated with increased incidence of airway trauma, unanticipated ICU admission and “cannot ventilate-cannot intubate” events.

For most ENT surgical procedures the patient’s airway is shared with the surgeon, and immediate access to the airway may be difficult or impossible. The ETT must be secured diligently to prevent an accidental extubation or pullout of the ETT to the subglottic area, which may result in exerting direct pressure on the recurrent laryngeal nerves by the ETT cuff. For certain procedures (e.g., excision of tumors of the base of the tongue) nasal intubation may be required to facilitate surgical access, and the surgeon should be consulted before induction.


ANESTHETIC MANAGEMENT

Some of the essential anesthesia management requirements for ENT surgery include: (1) assurance of good intraop and postop analgesia (most of the procedures are performed on highly reflexogenic areas); (2) quiet surgical field (the operated areas are highly vascular). Moderate controlled hypotension is widely employed: ↓SBP <100 mm Hg, MAP = 60-70 mm Hg, unless contraindicated; (3) immobility (for certain procedures profound muscle relaxation may be required, while for others administration of NMB must be avoided); (4) smooth emergence from anesthesia. The latter constitutes one of the most challenging tasks, as every attempt should be made to avoid or minimize the patient’s
reaction to the ETT during tracheal extubation. Straining, bucking, or coughing may provoke early postop bleeding (↑ venous and arterial pressure), disrupt delicate suture lines (e.g., facial nerve repair), dislodge surgical grafts (e.g., tympanoplasty), or cause additional trauma to the vocal cords after VC surgery. Many ENT surgeons have their own “list” of the procedures where the patient’s reaction to the ETT should be completely avoided during extubation, and an anesthesiologist should be familiar with the surgeon’s preferences.

Opioid-based anesthetic techniques are especially advantageous and result in significant ↓ MAC while providing sufficient blunting of the tracheal responses to the in-situ ETT. In an opioid-naive patient, the choice of an opioid analgesic depends primarily on several factors: anticipated surgical stimulation and postop pain, duration of surgery, coexisting medical conditions. High dose opioids (fentanyl: loading dose 3-10 mcg/kg iv, sufentanil: loading dose 0.5-1.5 mcg/kg iv), followed by either intermittent boluses or continuous infusion are the author’s preferred choice for major ENT surgery. For procedures that may be highly stimulating, but associated with minimal postop discomfort (e.g., laser surgery of the airway), shorter-acting opioids are preferred: remifentanil (loading dose 0.5-1.0 mcg/kg iv, infusion 0.1-0.3 mcg/kg/min iv).

TIVA is commonly employed, especially for endoscopic procedures. Most studies demonstrate that, compared to inhalational and balanced inhalational techniques, TIVA offers improved hemodynamic stability, quicker recovery times, decreased incidence of PONV, and improved patient satisfaction.

Maintenance of moderate controlled hypotension (MAP, 60-70 mmHg) is useful for maintaining optimal operating conditions. A variety of pharmacological approaches have been successfully employed for this purpose. The use of remifentanil is particularly effective in that regard, and is equally useful with both inhalational and TIVA techniques. The use of esmolol 0.5-1 mg/kg iv bolus, followed by continuous iv infusion 100-300 mcg/kg/min represents another attractive therapeutic option.

GETA is most widely employed. Use of a laryngeal mask airway (LMA) for ENT surgery, when feasible, is beneficial (↓ coughing, ↓ laryngospasm; see Table 3-3). Furthermore, the use of an LMA does not require NMB and facilitates the resumption of spontaneous ventilation. When used appropriately in selected patients, absence of immediate access to the patient’s airway is not a deviation from the standard of care.

A flexible laryngeal mask airway (FLMA), but not an LMA Classic™, LMA ProSeal™, or LMA Supreme™, is most frequently used in ENT anesthesia, because its shaft can be bent away from the surgical field without causing cuff displacement. Close communication between the surgeon and anesthesiologist is essential, as even a properly placed FLMA can become dislodged during surgical manipulations. The LMA-Proseal/Supreme is preferred whenever central positioning of the LMA can be safely maintained, (e.g., otologic surgery). Proper LMA insertion technique is crucial for minimizing the risk of aspiration or gastric insufflation especially if positive pressure ventilation (PPV) is planned. To minimize leaks, the largest size (FLMA #5) should be used for PPV whenever possible. Gastric insufflation is further minimized by ↓ Vt to 6-10 mL/kg and by keeping PIP < 20 cm H2O. The absence of gastric insufflation should be documented in the anesthesia record after auscultating the epigastric area.

Smooth emergence from anesthesia constitutes a particularly challenging task when GETA is used. Deeper stages of anesthesia are usually required until the very end of the procedure to blunt patient’s laryngo-tracheal responses. A low-dose remifentanil infusion to blunt the tracheal responses and promote smooth extubation may be helpful. The EC95 effect site concentration of remifentanil for blunting tracheal reflexes after balanced desflurane and sevoflurane anesthesia is in the range 2.3-2.9 ng/mL (corresponding manual infusion rate 0.08-1.0 mcg/kg/min).

Antiemetic prophylaxis should be routine and is most commonly achieved by iv administration of a 5-HT3 blocker. Multimodal antiemetic prophylaxis should be employed for patients at high risk for PONV. The addition of metoclopromide (10-20 mg iv) may be beneficial for the patients who had undergone the procedures resulting in accumulation of the passively swallowed blood in the stomach (e.g., nasal or intraoral surgery).








Table 3-3. Advantages of the LMA Compared with the ETT








































Adverse Event ETT:LMA


ETT %


LMA %


Ratio


Clinically significant problems


3.4


0.9


3.8


Laryngeal spasm


0.38


0.12


3.2


Aspiration


0.017


0.02


0.85


Sore throat


50


10


5


Laryngeal trauma


6.2


? (< 1)


> 6


Coughing on emergence


60


2


30


(Modified from Brimacombe JR, Brain AJ: The Laryngeal Mask Airway. A Review and Practical Guide, Saunders: 1997.)





Suggested Readings

1. Apfel CC, Philip BK, Cakmakkaya OS, et al: Who is at risk for postdischarge nausea and vomiting after ambulatory surgery? Anesthesiology 2012; 117:475-86.

2. Beer GM, Goldscheider E, Weber A, et al: Prevention of acute hematoma after face-lifts. Aesthetic Plast Surg 2010; 34:502-7.

3. Bitar G, Mullis W, Jacobs W, et al: Safety and efficacy of office-based surgery with monitored anesthesia care/sedation in 4778 consecutive plastic surgery procedures. Plast Reconstr Surg 2003; 111:150-6.

4. Blake DR: Office-based anesthesia: dispelling common myths. Aesthet Surg J 2008; 28:564-70.

5. Caloss R, Lard MD: Anesthesia for office-based facial cosmetic surgery. Atlas Oral Maxillofacial Surg Clin N Am 2004; 12:163-77.

6. Chuang YC, Wang CH, Lin YS: Negative pressure pulmonary edema: report of three cases and review of the literature. Eur Arch Otorhinolaryngol 2007; 264:1113-6.

7. Clevens RA: Avoiding patient dissatisfaction and complications in facelift surgery. Facial Plast Surg Clin North Am 2009; 17:515-30.

8. Friedberg BL: Propofol-ketamine technique: dissociative anesthesia for office surgery (a 5-year review of 1264 cases). Aesthetic Plast Surg 1999; 23:70-5.

9. Hoefflin SM, Bornstein JB, Gordon M: General anesthesia in an office-based plastic surgical facility: a report on more than 23,000 consecutive office-based procedures under general anesthesia with no significant anesthetic complications. Plast Reconstr Surg 2001; 107:243-51.

10. Kolodzie K, Apfel CC: Nausea and vomiting after office-based anesthesia. Curr Opin Anaesthesiol 2009; 22:532-8.

11. Liu YH, Li MJ, Wang PC, et al: Use of dexamethasone on the prophylaxis of nausea and vomiting after tympanomastoid surgery. Laryngoscope 2001; 111:1271-4.

12. Mamiya H, Ichinohe T, Kaneko Y: Negative pressure pulmonary edema after oral and maxillofacial surgery. Anesth Prog 2009; 56:49-52.

13. Niamtu J: Expanding hematoma in face-lift surgery: literature review, case presentations, and caveats. Dermatol Surg 2005; 31:1134-44.

14. Prendiville S, Weiser S: Management of anesthesia and facility in facelift surgery. Facial Plast Surg Clin North Am 2009; 17:531-8.

15. Steely RL, Collins DR Jr, Cohen BE, et al: Postoperative nausea and vomiting in the plastic surgery patient. Aesthetic Plast Surg 2004; 28:29-32.

16. Taub PJ, Bashey S, Hausman LM: Anesthesia for cosmetic surgery. Plast Reconstr Surg 2010; 125:1e-7e.

17. Westreich R, Sampson I, Shaari CM, et al: Negative-pressure pulmonary edema after routine septorhinoplasty: discussion of pathophysiology, treatment, and prevention. Arch Facial Plast Surg 2006; 8:8-15.


LARYNGOSCOPY/BRONCHOSCOPY/ESOPHAGOSCOPY


SURGICAL CONSIDERATIONS

Description: Laryngoscopy is used for inspection of the pharynx, hypopharynx, or larynx for diagnostic and/or therapeutic benefit. The patient is supine with cervical spine flexed and atlantoaxial joint extended (this position is best achieved with a headrest); and the teeth are protected with a mouth guard. The laryngoscope is introduced (Fig. 3-1); then, with a lifting motion, a thorough examination of the oropharynx, hypopharynx, laryngopharynx, and larynx is carried out and biopsies can be taken. Any bleeding normally can be controlled easily with cotton pledgets soaked in epinephrine, packing, or endoscopic cautery. Laryngoscopy often is combined with esophagoscopy,
bronchoscopy, or direct nasopharyngoscopy to survey the aerodigestive tract for malignancy. If the procedure is diagnostic, the surgeon may need to visualize the airway before intubation and/or muscle relaxation. If a laser is to be utilized, a special laser ETT, < 30% FiO2, and avoidance of N2O are required.






Figure 3-1. Placement of anterior commissure laryngoscope for laryngoscopy.

Usual preop diagnosis: Oropharyngeal, hypopharyngeal, or laryngeal tumors

Description: Operative microlaryngoscopy. A variety of laryngeal lesions, including papilloma, cysts, and polyps, can be removed endoscopically. Because of their close apposition to the delicate tissues of the vocal fold, a high degree of precision may be needed to remove the growth without damaging the underlying membrane. To this end, specialized endoscopes, such as the Dedo operating laryngoscope, are deployed transorally to allow the surgeon a binocular view of the vocal fold and the target lesion. They can be suspended from a Mayo stand to free both of the surgeon’s hands for operating. Using the microscope, a variety of specialized endoscopic instruments and the CO2 laser, the surgeon may be afforded excellent visualization of and unobstructed access to the vocal folds for diagnostic and therapeutic purposes. Operative microlaryngoscopy may necessitate several hours of work. Because of the precision involved in such procedures and the high degree of stimulation to the patient, general anesthesia (± jet ventilation) with muscle relaxation is required. Intubation with a small-caliber microlaryngeal or laser-safe tube (5 or 6 mm) may be required for these procedures. In cases where jet ventilation is to be performed, an endoscope suitable for this technique should be available. Intermittent apneic ventilation is also a possibility, although this involves periodic interruption of surgery, which can be cumbersome and distracting.

Usual preop diagnosis: Vocal fold neoplasm; vocal fold paralysis

Description: Bronchoscopy is used for visualization of the tracheobronchial tree for both diagnostic and therapeutic purposes. The patient is supine with head elevated and neck extended at the upper cervical level. The bronchoscope is directed along the right side of the tongue forward toward the midline to visualize the epiglottis. Next, the bronchoscope tip is used to lift the epiglottis and advance the bronchoscope through the vocal cords, into the trachea and bronchus (Fig. 3-2). With the aid of telescopes, the bronchoscope can be directed for inspection of the carina, main bronchi, and the segmental bronchi. Rigid bronchoscopes provide a large working channel through which to
introduce grasping and biopsy forceps. As such, rigid bronchoscopes may provide a more stable platform for removal or retrieval of foreign bodies, tumors, and stents than flexible fiberoptic bronchoscopes.






Figure 3-2. Rigid bronchoscopy showing adaptor (Racine) for anesthesia machine. Note neck flexion and head extension to align oropharyngeal and tracheal axes.

Flexible fiberoptic bronchoscopy is more commonly performed than rigid bronchoscopy. The endoscope is usually connected to a monitor, and suction, irrigation, and biopsy channels are self-integrated. Spontaneous ventilation can be maintained, which can allow the procedure to be performed without an ETT in place, affording unobstructed visualization of the entire upper airway. A bite block is usually placed to protect the endoscope from dental trauma and to allow easier advancement through the oropharynx into the larynx.

Usual preop diagnosis: Head and neck squamous-cell carcinoma; foreign body (FB) in bronchus

Description: Esophagoscopy is used for visualization of the esophagus for either diagnostic or therapeutic benefit. The patient is supine with head elevated and neck extended at the upper cervical level. The esophagoscope (held in the dominant hand) is advanced through the mouth behind the arytenoids, gently using the thumb of the nondominant hand. The bevel of the scope is then used to advance through the cricopharyngeal muscle (upper esophageal sphincter) with an upward lifting movement, entering the cervical esophagus. As the scope advances, the head may have to be lowered or the neck extended and the scope directed slightly toward the left. The scope is advanced to the gastroesophageal junction with great care to ensure a visible lumen is seen at all times to avoid inadvertent perforation. Flexible fiberoptic esophagoscopy is performed in an essentially identical manner. Superior visualization has made this the technique of choice for many surgeons. Biopsies may be taken and percutaneous gastrostomy tubes may be placed using the fiberoptic esophagoscope.

Usual preop diagnosis: Head and neck squamous-cell carcinoma; FB ingestion

Description: Panendoscopy, or triple endoscopy, is the combination of laryngoscopy, bronchoscopy, and esophagoscopy. It is usually performed as part of the evaluation of patients with newly diagnosed cancer of the head and neck for several reasons: (a) to gauge the extent of the primary tumor and to evaluate resectability; (b) to evaluate for the presence of synchronous tumors in other locations within the upper aerodigestive tract; and (c) to identify the source of the primary lesion in patients who present with secondary cervical metastases. In the 3rd case, after PET-CT, endoscopy is supplemented with directed biopsies from those locations most likely to contain the occult primary lesion, including the nasopharynx, tonsillar fossae, and tongue base, with tonsillectomy commonly performed as well. Identification of the source of the primary lesion allows for more directed therapy, tailored irradiation fields, improved local control, and decreased morbidity.

Usual preop diagnosis: Head and neck squamous-cell carcinoma.





ANESTHETIC CONSIDERATIONS

(Procedures covered: bronchoscopy, esophagoscopy, panendoscopy, operative microlaryngoscopy, Zenker’s diverticulectomy, laser surgery of the airway)


PREOPERATIVE

Many of these patients are elderly and have a history of smoking and alcohol abuse with corresponding implications for intraop management. Patient fluid and nutritional status may be further compromised by preexisting malignancy. Meticulous attention to airway management is paramount in these procedures, and close communication with the surgeon is essential. Some patients presenting for esophagoscopy may have obstructing lesions of the esophagus or Zenker’s diverticulum, active gastrointestinal bleeding, or require the removal of a foreign body, putting them at increased risk of aspiration.
































Airway


Although rare, the airway may be compromised in these patients at both the upper and lower airway levels; thus a thorough preop airway assessment is essential. A clear backup plan for securing the airway should be devised and discussed with the surgeon before induction of GA. Stridor at rest suggests an airway narrowing ≤4.5 mm, although the airway diameter can be seriously reduced even without stridor being present. Patients with lesions in the mediastinum may have involvement of the recurrent laryngeal nerve, presenting with hoarseness and potential airway management problems (e.g., difficult mask ventilation, difficult intubation, ↑ aspiration risk). (See also Anesthetic Considerations for Laryngectomy, p. 206)


Respiratory


These patients may have a high incidence of COPD and ↓respiratory reserve. The nature and characteristics of a productive cough must be noted. Wheezing on exam must be treated with bronchodilators before induction. Patients presenting with vocal cord (VC) paralysis or achalasia may have had the repeated episodes of pulmonary aspiration.


Tests: CXR; other tests as indicated from H&P


Dental


Physical exam should include a careful dental assessment and documentation of any missing, loose, or damaged teeth. Patients (or parents, as appropriate) should be informed that dental trauma may occur as a result of surgical instrumentation of the patient’s mouth during the procedure.


Cardiovascular


Adrenergic responses during endoscopy may be associated with up to a 4% incidence of myocardial ischemia. Careful preop Hx and thorough physical exam should be undertaken in patients with Hx of CAD and CHF, or those with cardiac risk factors (including age > 40 yr, male, HTN, hypercholesterolemia, long Hx of smoking, obesity, and family Hx). The volume status of debilitated patients who are unable to eat because of obstructing lesions of the esophagus should be assessed by measuring orthostatic BP changes.


Tests: ECG; other tests as indicated from H&P


Neurologic


Some patients may have Hx of ETOH abuse, which may result in ↑ anesthetic requirements 2° hepatic enzyme induction. Symptoms of alcohol withdrawal (e.g., tremulousness, ↑ sympathetic activity, and altered mental status), if present, should be controlled before surgery.


Hematologic


Patients with malignancy or chronic disease may have evidence of anemia or coagulopathy.


Tests: CBC; coagulation studies as indicated from H&P


Gastrointestinal


In some patients (e.g., with malignant tumors), significant electrolyte abnormalities may be present 2° malnutrition. Hypokalemia and hypomagnesemia should be corrected preop. In patients with Hx of ETOH abuse, liver disease and cirrhosis may be present.


Tests: Electrolytes; BUN; Cr; LFT; coag studies, as indicated from H&P


Premedication


An antisialogogue (e.g., glycopyrrolate 0.2 mg iv) may be desired by the surgeon to faciliate panendoscopy, especially in patients with copious secretions. Sedative premedication is routine, but should be minimized in the elderly and avoided in patients with symptoms of upper airway obstruction.




INTRAOPERATIVE

Anesthetic technique: GETA. Airway management requires careful planning and continuous communication with the surgeon. Surgical requirements include adequate muscle relaxation (movement, coughing, or bucking during endoscopy may have disastrous consequences) and immobile vocal cords for vocal cord surgery. Cardiovascular stability is important: laryngeal, tracheal, and carinal reflexes may provoke severe ↑ BP and ↑ HR, which can be detrimental in some patients. Adequate depth of anesthesia is essential, but the requirements for rapid awakening and return of laryngeal reflexes present additional challenges in anesthetic management. Short-acting β-blockers (e.g., esmolol) may be indicated to treat breakthrough sympathetic responses, especially in patients with cardiac disease. Remifentanil or alfentanil (see Introduction, p. 178) is useful for these procedures, which, although highly stimulating, are characterized by minimal or absent postop pain, and the majority of patients are discharged home from the recovery room.

Special considerations: If flexible bronchoscopy is planned, the patient’s trachea is intubated in routine fashion by the anesthesiologist with a large-diameter ETT (7.5-8.0 mm ID) to acommodate a flexible video bronchoscope. The ETT is usually taped midline. As an alternative, in selected patients, flexible bronchoscopy can be performed without tracheal intubation through the Patil-Syracuse mask during manual bag-mask ventilation. Placement and manipulation of the flexible bronchoscope by the surgeon will be facilitated by the concomitant use of one of the hollow oral airways used for the fiberoptic intubation (e.g., Williams airway). The patient can then be tracheally intubated with a smaller diameter ETT (e.g., 6.0 mm ID), to facilitate surgical access.


Flexible esophagoscopy is rarely performed as an isolated procedure but, if done, would also be facilitated by tracheal placement of a small-diameter (e.g., 6.0 mm ID) ETT. The ETT is usually moved over to the left corner of the mouth and taped to the lower jaw, to provide more room for the esophagoscope advancement and manipulation.

If rigid bronchoscopy is planned first, GA is induced, and the patient is hyperventilated through the face mask with FiO2 = 1.0. Following muscle relaxation, the surgeon may proceed, without securing an airway. Quick and gentle DL for application of topical lidocaine to the larynx and upper trachea (LTA, 4% lidocaine 3-4 cc) before rigid bronchoscopy may help blunt hemodynamic responses to the subsequent surgical manipulation. DL with LTA should be avoided in patients with tumors at the base of the tongue (↑ risk of bleeding; see Anesthetic Considerations for Glossectomy, p. 212) or when preexisting copious secretions or bleeding are present in the upper airway 2° risk of pulmonary aspiration on emergence from anesthesia. It is advisable to demonstrate to the surgical team and document in the chart absence of dental damage after DL has been performed.

After the rigid bronchoscope is introduced into the patient’s trachea, it is connected to an anesthesia circuit through a flexible side port adapter (Racine, Fig. 3-1), and the patient is ventilated manually. High flows are usually required because of the leak around the bronchoscope. Close communication with the surgeon is essential for adjusting ventilation when the bronchoscope is introduced into the mainstem bronchus to avoid high inflating pressures and to ensure complete exhalation (↓ risk of barotrauma). After rigid bronchoscopy is completed, mask ventilation with FiO2 = 1.0 before intubation is advisable to ensure adequate oxygenation and normocapnia. A reinforced ETT is useful for rigid esophagoscopy to avoid possible compression of the ETT. The ETT should be moved to the left side of the patient’s mouth to facilitate introduction of the surgical instruments and taped to the lower jaw because full opening of the patient’s mouth is required.

For operative microlaryngoscopy, a small-diameter (usually 5.0 mm ID), cuffed long microlaryngeal tube (MLT) is most commonly used to facilitate visualization of the larynx, but will interfere with posterior glottis lesions, for which jet ventilation (see below) is most commonly employed. The CO2 laser, which can precisely vaporize superficial tissue, is widely used for vocal cord laser surgery, whereas the Nd:YAG (neodymium-yttrium-aluminumgarnet) laser is usually employed for airway tumor debulking because of its ability to coagulate deeper lesions. The Nd:YAG can be used through the suction channel of the fiber optic or video bronchoscope, whereas the CO2 laser must be aimed directly at the targeted tissue. Both the CO2 and Nd:YAG wavelengths lie outside the visible spectrum, and a separate, lower energy visible beam is used for aiming. The patient must be motionless, the patient’s eyes must be protected with tape and moistened gauze, and OR personnel must wear protective goggles.

An intermittent apnea technique involves hyperventilation, followed by intermittent tracheal extubation for 1-5 min, during which the laser is used. This approach is time consuming and may be associated with a higher incidence of airway trauma and edema 2° repeated intubations. Careful pulse oximeter monitoring is essential for this technique.

Manual low-frequency jet ventilation (Fig. 3-3), or automated high-frequency jet ventilation (HFJV) may be necessary when an ETT cannot be used (e.g., some supraglottic and subglottic lesions). For supraglottic manual jet ventilation, the ventilating laryngoscope is most commonly employed. The axis of the jet should be in line with the trachea, and full egress of air (complete chest deflation) should be ensured between the jet ventilator “puffs.” Close communication with the surgeon is essential. The jet should be triggered during pauses between laser firings to keep the vocal cords immobile. If jet ventilation is used for laser resection of papillomas, there is a risk of spreading the virus to OR personnel, and special face masks should be worn in the OR. Jet ventilation generally provides adequate ventilation without introducing flammable material into the airway or obstructing the surgical field. Its use, however, may be associated with potentially severe complications, including barotrauma, pneumothorax and gastric distension (risk of regurgitation), and is hindered by ↓ chest-wall into the airway or lung compliance. Full muscle relaxation is usually required to facilitate precise laser firing. HFJV is most commonly delivered through a subglottic catheter or specialized tube (e.g., Hunsaker tube).

For laser cases, precautions must be taken to prevent airway fire, including



  • Use special laser ETT (e.g., Mallinkrodt Laser-Flex, Xomed Laser Shield), although none of them provides 100% protection from all types of lasers. Small (5.0 mm ID and smaller) diameter laser ETTs are preferred to facilitate surgical access.


  • Use the lowest possible FiO2 (≤ 0.3 strongly preferred), that will ensure adequate oxygenation (dilute O2 with air, N2, or helium) and avoid N2O (both O2 and N2O promote combustion).


  • Use colored (methylene blue-tinged) NS in the ETT cuff (will immediately alert the surgeon in case of a laser hit).


  • Place the ETT sufficiently deep into the trachea for the cuff to reduce the risk of laser contact.

Similar considerations apply in patients undergoing endoscopic Zenker’s diverticulectomy, when the CO2 laser is used.







Figure 3-3. Rigid endoscope with modified Sanders jet ventilation technique. The oxygen supply at 50 psi is connected to a reducing valve that allows the pressure to be adjusted from 0 to 50 psi. The side port of the endoscope is used as the Venturi injector site, and the open end can be used for continuous viewing by the endoscopist.













































Induction


Patients at risk for aspiration may require RSI with cricoid pressure (CP) if symptoms of active gastroesophageal reflux disease are present. Otherwise, anatomical location of the diverticulum (above the cricoid cartilage) makes application of CP largely ineffective. With the possible exception of endoscopic Zenker’s diverticulectomy, fentanyl use should be minimized (1-2 mcg/kg) or even completely avoided in favor of the short-acting opioids (remifentanil or alfentanil iv; see Introduction, p. 178), 2° minimal postop pain. Propofol (1-2 mg/kg) is the ideal induction agent. Patients with mobile, floppy, supraglottic tumors (e.g., papillomatosis, epiglottic cancer, large vocal cord polyps) are at ↑ risk for complete airway obstruction after induction of GA with or without neuromuscular blockade. Anesthetic management of these patients requires careful planning and meticulous preparation (see Anesthetic Considerations for Laryngectomy, p. 206.) The surgeon should be consulted about the extent of the disease and the potential need for a tracheostomy. If the disease is severe, the surgeon should be present during induction for the possible need to perform urgent or emergent rigid bronchoscopy or cricothyrotomy/tracheostomy.


Maintenance


TIVA (e.g., propofol: 80-180 mcg/kg/min; remifentanil 0.1-0.25 mcg/kg/min) is widely used, especially when rigid bronchoscopy or jet ventilation/intermittent apnea techniques are planned. Compared to alfentanyl, the use of remifentanil during TIVA is associated with the increased hemodynamic stability, reduction in propofol dose and faster respiratory recovery. When the ETT is used throughout the case, delivery of anesthetic gases may be used instead of a propofol infusion, especially if a bronchodilating effect is desirable. Desflurane and sevoflurane are the preferred agents because of their low blood:gas solubility; sevoflurane may be favored in patients with preexisting cardiac disease to minimize the risk of a dose-dependent tachycardia. Breakthrough sympathetic responses can be managed safely by administration of β-blockers iv or small boluses of a short-acting opioid (see Introduction, p. 178). With intermittent apnea or jet ventilation techniques, it may be difficult to avoid hypercapnia and hypoxemia, which may provoke intraop dysrhythmias.


Full muscle relaxation is routine: vocal cord immobility is essential for microlaryngeal and laser surgery. Monitoring the neuromuscular blockade may be more accurate at the facial nerve (orbicularis oculi muscle), than the ulnar nerve (adductor pollicis muscle) because the recovery of the former better reflects the recovery of the laryngeal muscles. Care should be taken to avoid inadvertent prolonged neuromuscular blockade by coordinating administration of additional doses of muscle relaxants with the surgeon. As the surgery approaches its end, deepening the level of anesthesia may be the preferred approach to minimize VC movement. A succinylcholine infusion (2-6 mg/min iv) can be used safely in selected patients (limiting the total dose of succinylcholine ≤ 4-6 mg/kg will help avoid phase 2 block).


Emergence


Patient should have full return of protective airway reflexes prior to extubation. The patient’s stomach may need to be decompressed following jet ventilation. Smooth emergence from anesthesia is obligatory to avoid additional trauma to the vocal cords. For this reason, some surgeons request deep extubation after vocal cord surgery, which presents extra challenges to the anesthesiologist (see Emergence for Tonsillectomy, Adenoidectomy, p. 210).


Blood and fluid requirements


IV: GI bleeder: 14-16 ga × 2 Others: 20 ga × 1


NS/LR @ 2-3 mL/kg/h


Blood loss is usually minimal; however, in patients with ↑ risk of GI bleed, blood loss may be massive. T&C these patients for 2 U PRBC with blood immediately available in OR.


Monitoring


Standard monitors (p. B-1). ± arterial line


In patients with ↑ risk of GI bleed, an arterial line is desirable.


Positioning


OR table rotated 90° or 180° away from the anesthesiologist


[check mark] and pad pressure points


[check mark] eyes


A shoulder roll is placed and the patient’s neck is extended to facilitate endoscopy. Special attention should be paid to prevent compression of the patient’s shoulder by the vertical bar of the Mayo stand, which is frequently employed for suspending the operating laryngoscope or endoscope.


Complications


Inadequate ventilation Loss of airway


Hypoxia and hypercarbia may be difficult to avoid with jet ventilation.


Perforation of airway Dysrhythmias Pneumothorax


Mechanical or laser perforation of the airway may → bronchospasm or uncontrollable hemorrhage. Dx: ↑RR, ↓BP, ↑CVP, wheezing, ↓O2 saturation, ↑PIP, SOB, chest pain, ↓breath sounds, ↓ECG amplitude, dullness on percussion. Rx: chest tube or needle aspiration, FiO2 = 1.0, ventilation and volume expansion.



Eye trauma Bleeding postbiopsy


Eye trauma from surgical instruments used during endoscopy may require ophthalmology consult.


Airway fire (steps taken simultaneously by the anesthesiologist and surgeon)


Disconnect the inspiratory limb of the anesthesia circuit.


Remove ETT


Extinguish fire with oral NS


Remove all burning material


Resume ventilation by face mask with 100% O2 . Consider reintubation.


Flexible fiberoptic bronchoscopy.


Save ETT for later examination.


This is an acute, life-threatening emergency. NB: turning ventilator off only may not be sufficient due to continued delivery of fresh gas to the patient’s lungs. Rigid or flexible bronchoscopy is required to [check mark] extent of damage, presence of ETT fragments, and airway edema. All inhaled gases should be humidified. Patients are usually reintubated and monitored in the ICU.


To assess lower airway damage and to remove ETT fragments.




POSTOPERATIVE
































Complications


Dental trauma Bleeding Eye trauma


Dental trauma may result from surgical manipulation of the airway, and the anesthesiologist must check the teeth immediately after airway access is gained. If dental trauma is detected, notify the surgeon to discuss management options, both immediate and subsequent.



Postop airway compromise


Has a higher incidence than in general surgery patient population. Patients with T3 lesions and those with associated laryngeal biopsy (↑ airway swelling) after panendoscopy may be at high risk for reintubation in PACU. Delayed upper airway edema after laser surgery has been described, when the coagulation (Nd:YAG) laser is used.



Esophageal perforation


Complaints of painful swallowing as well as fever, tachycardia, neck/chest/back pains postop may suggest an esophageal perforation.



Pneumothorax


Pneumomediastinum


Hemothorax


Aspiration


Pneumothorax (see above), mediastinal air or hemothorax from esophageal perforation may present as ↓ BP and cardiovascular collapse.


Pain management


Short-acting opiod


Fentanyl 25-50 mcg iv prn is usually sufficient.


Tests


[check mark] CXR


For evidence of pneumothorax, hemothorax, mediastinal air.




Suggested Readings

1. Abdelmalak B, Ryckman JV, AlHaddad S, et al: Respiratory arrest after successful neodymium:yttrium-aluminum-garnet laser treatment of subglottic tracheal stenosis. Anesth Analg 2002; 95:485-6.

2. Bacher A, Lang T, Weber J, et al: Respiratory efficacy of subglottic low-frequency, subglottic combined-frequency, and supraglottic combined-frequency jet ventilation during microlaryngeal surgery. Anesth Analg 2000; 91:1506-12.

3. Braverman I, Sichel JY, Halimi P, et al: Complication of jet ventilation during microlaryngeal surgery. Ann Otol Rhinol Laryngol 1994; 103:624-7.

4. Donati F, Meistelman C, Benoit P: Vecuronium neuromuscular blockade at the adductor muscles of the larynx and adductor pollicis. Anesthesiology 1991; 74:833-7.

5. Gaumann DM, Tassonyi E, Fathi F, et al: Effects of topical laryngeal lidocaine on the sympathetic response to rigid panendoscopy under general anesthesia. J Otorhinolaryngol Relat Spec 1992; 54:49-53.

6. Hill RS, Koltai PJ, Parnes SM: Airway complications from laryngoscopy and panendoscopy. Ann Otol Rhinol Laryngol 1987; 96:691-4.

7. Jaquet Y, Monnier P, Van Melle G, et al: Complications of different ventilation strategies in endoscopic laryngeal surgery: a 10-year review. Anesthesiology 2006; 104:52-9.

8. McRae K: Anesthesia for airway surgery. Anesthesiol Clin North Am 2001; 19:497-541.

9. Ozkose Z, Yalcin Cok O, Tuncer B, et al: Comparison of hemodynamics, recovery profile, and early postoperative pain control and costs of remifentanil versus alfentanil-based total intravenous anesthesia (TIVA). J Clin Anesth 2002; 14:161-8.



TRACHEOTOMY/TRACHEOSTOMY AND CRICOTHYROIDOTOMY


SURGICAL CONSIDERATIONS

Description: When an airway needs to be obtained right away and intubation is not an option, a cricothrotomy is indicated. A vertical incision is made in the midline through the cricothyroid membrane, an initial influx of air is facilitated if the patient is spontaneously breathing, and a small ETT placed. It is wise to convert this to a tracheostomy as soon as it is convenient to do so as this reduces the subsequent incidence of subglottic stenosis and cricoid chondritis.

A tracheotomy is generally done in a controlled setting, either under general anesthesia in an intubated patient or under local anesthesia. Either a short transverse incision 1-2 cm inferior to the cricoid or a midline vertical incision beginning at the same location may be used. Strap muscles are retracted laterally, the thyroid isthmus is divided if necessary, and in adults an inferiorly based tracheal flap consisting of the 2nd or 3rd tracheal ring is made and secured to the skin inferiorly. In small children, it is better to make only a vertical midline incision to minimize the incidence of stenosis; left and right stay sutures are then placed to assist in reintubation in the event of accidental dislodgment of the tracheotomy tube. The tracheotomy tube in all patients is secured to the skin with sutures. Trach ties supplement this securing of the tube unless these circumferential ties would interfere with venous drainage of a flap used in the head and neck reconstruction.

When prolonged use of a tracheotomy is anticipated and it is unlikely that mechanical ventilation will be needed, there are specialized silicon tracheotomy tubes with minimal intraluminal plastic and may be associated with fewer intraluminal potential complications.

Usual preoperative diagnosis: Indications for tracheostomy are numerous, but share the common theme of securing a safe airway either in anticipation of postop airway edema, inability to protect the airway from aspiration, or as an urgent need to obtain an upper airway in pending obstruction. The fastest way to obtain an airway in an outright emergency when intubation is not an option is a cricothyrostomy. Another 3rd general indication is to protect the larynx from injury if prolonged intubation is anticipated, such as in a prolonged ICU setting or in paralysis associated with cervical spinal cord trauma. Rarer indications are bilateral vocal cord paralysis or a history of recurrent allergy associated with larynogspasm.





ANESTHETIC CONSIDERATIONS


PREOPERATIVE

Typically, there are three patient populations presenting for tracheostomy: (1) critically ill intubated patients in chronic respiratory failure or following major trauma; (2) patients for whom tracheostomy is part of a scheduled procedure (e.g., laryngectomy); and (3) patients with impending or total upper airway obstruction (e.g., Ludwig’s angina, retropharyngeal abscess). If the latter constitutes life-threatening emergency, tracheotomy/cricothyroidotomy may be the preferred approach. Aside from an occasional otherwise healthy patient in the 3rd category, all patients presenting for tracheostomy are usually debilitated, have associated cardiac or pulmonary disease, and frequently present with neurological and metabolic abnormalities.


























Respiratory


Patients in group 1 usually require mechanical ventilation with PEEP to maintain adequate oxygenation. The continued application of PEEP may be an important consideration during their transport from ICU to OR. Patients in group 2 require a careful airway evaluation (see Anesthetic Considerations for Neck Dissection, p. 220, and Laryngectomy, p. 206). Based on the assessment, the anesthesiologist must decide whether to choose a DL, an awake FOI, or a tracheostomy under local anesthesia to secure the airway. Patients in group 3 will usually require semi-emergent or emergent tracheostomy. Patients in all three groups should be evaluated for the presence of possible recurrent aspiration. Tests: CXR; ABG, as indicated from H&P


Cardiovascular


All patients may have significant cardiac risk factors, including smoking, ETOH abuse, male gender, ↑ cholesterol, family Hx, and HTN. Some patients may have recently undergone major cardiac surgery and may be on pharmacological inotropic support, with full invasive monitoring, including PA line. Tests: ECG, and other tests as indicated, in patients of the 2nd group


Neurological


Preop neurological deficits should be fully documented.


Hematologic


In cases of malignancy or chronic disease, coagulopathies or anemia may be present Tests: CBC; Coagulation studies.


Laboratory


Other tests as indicated from H&P


Premedication


Standard premedication (p. B-1) in elective cases. Premedication is best avoided in critically ill patients and patients with symptoms of upper airway obstruction.




INTRAOPERATIVE

Anesthetic technique: GETA in intubated patients, or in patients who pose no problems for conventional DL and tracheal intubation. In the presence of significant airway compromise or anticipated very difficult intubation local anesthesia may be required. Most tracheostomies are elective or semiurgent and are performed under GA. Patients with ↑ mucosal swelling (e.g., generalized edema, prolonged intubation) and ↑ tissue fragility (e.g., chronic steroid therapy) are at risk for tracheal mucosal separation → creation of a false passage during tracheostomy. This will constitute a true emergency (see Postoperative Complications, below).









































Induction


If already intubated (group 1, above), convert preexisting ICU sedation to GA, using carefully titrated induction (e.g., etomidate 0.2-0.3 mg/kg iv) or an inhalational agent. If not intubated, and no airway problems are anticipated, a standard induction (p. B-2) may be appropriate. If airway problems are anticipated, an awake FOI or tracheostomy performed under local anesthesia may be the techniques of choice (see Anesthetic Considerations for Neck Dissection, p. 220, and Laryngectomy, p. 206). In any event, the anesthesiologist should be prepared to deal with a failed intubation and have a surgeon immediately available to perform cricothyrotomy/tracheostomy if ventilation proves impossible.


Maintenance


Standard maintenance (see p. B-3). Full muscle relaxation is required. FiO2 = 1.0 usually is required before insertion of the tracheostomy tube. This high O2 concentration, combined with electrocautery, may precipitate airway fire (see Postoperative Complications, below). A cuffed ETT should be used to prevent O2 from leaking into the surgical site. In order to avoid inadvertent ETT cuff puncture, consider advancing the ETT closer toward the carina, before the trachea is opened. The trachea is usually opened above the cuff, and the ETT is slowly retracted cephalad, under direct vision by the surgeon (NOTE: Do not remove the ETT completely!). Sterile gas sampling tubing, extra ETTs, and anesthesia circuit should be readily available (see Maintenance for Laryngectomy, p. 207). After the tracheostomy tube is secured, it should be suctioned and connected to the anesthesia circuit. Verify the ETCO2 tracing, 3 the inflation pressures, and remove the ETT.


Emergence


Considerations for group 2 and 3 patients are described above. Patients in the first group will continue on ventilatory support in the ICU. The tracheostomy tube must be carefully suctioned, and the delivered O2 should be humidified. Opioid sedation will minimize reaction to suctioning in the early postop period. Tracheostomy tubes should not be removed for at least the first 5-7 days until a track is formed.


Blood and Fluid Requirements


IV: 18 ga × 1 NS/LR @ 2-3 mL/kg/h


EBL is typically minimal, when the tracheostomy is performed as an isolated procedure


Monitoring


Standard monitors (p. B-1)


Avoid ECG pad placement in the prepped area. Invasive monitoring may be appropriate depending on the patient’s condition.


Positioning


Shoulder roll [check mark] and pad pressure points [check mark] eyes


A shoulder roll is usually placed, and patient’s neck extended, which may result in ETT cuff migrating cephalad, closer to the incision site (danger of inadvertent perforation by the surgeon on entering the trachea!). Make sure the ETT is positioned at the sufficient depth and taped securely.


Complications


Pneumothorax Pneumomediastinum Hemorrhage Aspiration of blood


False tracheal passage/tracheal disruption


Difficult ETT insertion/reinsertion


Pneumothorax may occur with a low neck dissection, or if a false passage (see Postop Complications, below) has been created during the tracheostomy tube insertion. Dx and Rx—see Anesthetic Considerations for Laryngoscopy/Bronchoscopy/Esophagoscopy, p. 184. This is an airway emergency and must be quickly recognized (absent CO2, ↑ PIP, absent or very distant breath sounds). Reintroduction of the existing ETT from the proximal trachea should be attempted.




Rigid bronchoscope should be available to reestablish the airway, in case of a failed reintubation. An alternative approach is to insert a large-bore iv catheter into the tracheal lumen distal to the tracheostomy site and jet-ventilate the patient. Insertion of an airway exchange catheter through the bronchoscopy elbow adapter attached to the existing ETT has been advocated prior to tracheostomy tube insertion in patients at high risk for this complication.



Airway fire


Tracheostomy fires are usually not catastrophic, possibly because the tracheostomy acts as a vent. Rx: immediately disconnect the patient from the anesthesia machine, extinguish the fire with NS, and ventilate the lungs with room air using a self-inflating bag. Removing or changing the existing ETT at this point may be more risky than leaving it in, especially if the patient was previously difficult to intubate or the airway has become edematous.




POSTOPERATIVE




















Complications


Pneumothorax


Pneumomediastinum


Hemorrhage


Occlusion of the tracheostomy tube


Tracheostomy tube displacement


See Postoperative complications after Laryngoscopy/Bronchoscopy/Esophagoscopy, p. 189.


This could be due to secretions, mucus plug, blood, or positioning of the tube in the mainstem bronchus or against the tracheal wall. Reintubate orally or through the tracheostomy site


Pain management


PCA (p. C-3)


IV opioids



Tests


CXR


[check mark] tracheostomy tube position and 3 for evidence of either pneumothorax or pneumomediastinum




Suggested Readings

1. Atkins JH, Mirza N: Anesthetic considerations and surgical caveats for awake airway surgery. Anesthesiol Clin 2010; 28(3): 555-75.

2. Brown BR: Anaesthesia for ear, nose, throat and maxillofacial procedures. In: Prys-Roberts C, Brown BR, eds. International Practice of Anaesthesia. Butterworth-Heinemann, Oxford: 1996, 2-9.

3. Chee WK, Benumof JL: Airway fire during tracheostomy: extubation may be contraindicated. Anesthesiology 1998; 89:1576-8.

4. Donlon JV, Feldman MA: Anesthesia for eye, ear, nose, and throat surgery. In: Miller RD, ed. Miller’s Anesthesia, 6th edition. Elsevier, Philadelphia: 2005, 2527-49.

5. Mcguire G, El-Beheiry H, Brown D: Loss of the airway during tracheostomy: rescue oxygenation and re-establishment of the airway. Can J Anesth 2001; 48:697-700.

6. Rogers ML, Nickalls RWD, Brackenbury ET, et al: Airway fire during tracheostomy: prevention strategies for surgeons and anaesthetists. Ann R Coll Surg Engl 2001; 83:376-80.

7. Sheinbein DS, Loeb RG: Laser surgery and fire hazards in ear, nose, and throat surgeries. Anesthesiol Clin 2010; 28(3): 485-96.



INTUBATION FOR EPIGLOTTITIS


ANESTHETIC CONSIDERATIONS


PREOPERATIVE

Epiglottitis is an acute inflammation and swelling of the epiglottis, associated with a generalized systemic toxicity, usually due to Haemophilus influenza Type B. It also can be caused by β-hemolytic streptococci, staphylococci, pneumococci, or unusual pathogens among immunocompromised individuals and drug/alcohol abusers. It occasionally results in total laryngeal obstruction and death 2° asphyxia. At one time, the typical patient was a previously healthy child 3-5 yr old; however, since the advent of the H-flu vaccine, epiglottitis is more common in adults (predominantly males). The most common presenting symptoms are sore throat, dysphagia/odynophagia, fever, respiratory difficulty, and drooling. Pediatric patients may appear toxic on presentation.




















Airway


Enlarged epiglottis seen frequently on neck x-ray. Neck tenderness or swelling also observed in some patients. Patients with stridor are at high risk for upper airway obstruction.


Respiratory


The patient, typically sitting upright, may display hoarseness, muffled voice, dyspnea, and chest-wall retractions. NB: Rapid treatment should be instituted instead of performing time-consuming investigations. The sudden development of respiratory obstruction in the x-ray suite could have a disastrous outcome.


Hematologic


A high leukocyte count usually is found in these patients.


Tests: Blood drawing before the airway is secured may be inadvisable.


Premedication


None



INTRAOPERATIVE

Anesthetic technique: GETA. Patients presenting with imminent or actual airway obstruction should be intubated immediately. Airway management for adult patients presenting with mild-to-moderate symptoms is controversial. Although routine prophylactic intubation of these patients may not be necessary, 18% subsequently develop complete airway obstruction; thus, close monitoring is mandatory if intubation is deferred. It is imperative to realize that total airway obstruction can occur suddenly and without warning.

An experienced anesthesiologist should be present for this procedure. In the pediatric patient, it is critical that neither visualization of the epiglottis nor other maneuvers be attempted to confirm the Dx before anesthesia. In adults, it has been suggested that indirect laryngoscopy or FOB may be performed without the risk of precipitating complete airway obstruction, although this approach is controversial.































Induction


If an iv is in place, atropine 0.02 mg/kg may be given to the pediatric patient to prevent vagal reflexes resulting from manipulation of the inflamed epiglottis. If no iv access is available, inhalation induction (sevoflurane in FiO2 = 1.0) with the patient in the sitting position should be used. Intramuscular injection should be avoided to prevent agitation, crying, and subsequent total airway obstruction (iv line is placed after induction of anesthesia). An experienced ENT surgeon, ready to perform an emergency tracheostomy, must be present at induction. Early application of CPAP is essential to maintain the upper airway patency. Inhalation induction may be prolonged and intubation extremely difficult. Different sizes of ETTs must be available.


Maintenance


Standard maintenance (see p. B-3)


Emergence


The patient will remain intubated for 24-48 h and should be kept sedated and restrained to prevent accidental extubation.


Blood and fluid requirements


IV: 18-20 ga (adult) 22-26 ga (child)


NS/LR @ 3-5 mL/kg/h (adult); @ 1.5 mL/kg/h (child)


Minimal blood loss


Fluid requirements may be ↑ 2° fever and dehydration.


Monitoring


Standard monitors (p. B-1)


Positioning


[check mark] and pad pressure points


[check mark] eyes


Complications


POPE (postobstructive pulmonary edema)


A short-lived POPE occasionally occurs after relief of the obstruction and must be treated with IPPV.




POSTOPERATIVE
















Complications


Accidental extubation


ETT blockage


These complications can prove fatal. The blockages are sometimes due to crusting of the ETT 2° insufficient humidification.


Pain management


PCA (p. C-3)


IV opioids


Postop sedation and manual restraints are often required.




Suggested Readings

1. Crockett DM, Healy GB, McGill TJ, et al: Airway management of acute supraglottitis at the Children’s Hospital, Boston: 1980-1985. Ann Otol Rhinol Laryngol 1988; 97(2Pt1):114-19.

2. Dort JC, Frohlich AM, Tate RB: Acute epiglottis in adults: diagnosis and treatment in 43 patients. J Otolaryngol 1994; 23:281-5.

3. Feldman MA, Patel A: Anesthesia for eye, ear, nose, and throat surgery. In: Miller RD, ed. Miller’s Anesthesia, 7th edition. Elsevier, Philadelphia: 2010, 2357-88.

4. Park KW, Darvish A, Lowenstein E: Airway management for adult patients with acute epiglottitis. Anesthesiology 1998; 88:254-61

5. Senior BA, Radkowski D, MacArthur C, et al: Changing patterns in pediatric supraglottitis: a multi-institutional review, 1980 to 1992. OHNS 1994; 110:203-10.

6. Verbruggen K, Halewyck S, Deron P, Foulon I, Gordts F: Epiglottitis and related complications in adults. Case reports and review of the literature. B-ENT 2012; 8(2):143-8.


ZENKER’S DIVERTICULECTOMY (OPEN APPROACH)


SURGICAL CONSIDERATIONS

Description: Zenker’s diverticulum is a herniation of mucosa through the posterior hypopharyngeal wall immediately above the cricopharyngeus muscle and below the inferior constrictor in an area called Killian’s dehiscence. This is an acquired disorder, usually seen in the 6th to 9th decades of life and felt secondary to tonic spasm or achalasia of the cricopharyngeus muscle. Clinically, patients may experience dysphagia, globus, coughing, and regurgitation of undigested food. Weight loss and aspiration pneumonia can be seen in severe cases. Barium swallow is usually diagnostic. Endoscopy will reveal the presence of a pouch of variable size posterior to the cricopharyngeus muscle often filled with undigested debris. Cricopharyngeal achalasia may present in the absence of a well-formed diverticulum with much the same symptom complex. Treatment is usually aimed at division of the cricopharyngeus muscle and eradication of the pouch.

Variant approaches. Open: Under GA with muscle relaxation, an incision is made in the left side of the neck to expose the diverticulum and cricopharyngeus muscle. The muscle is cut, the diverticulum resected, and the hypopharyngeal defect closed. In patients with pure cricopharyngeal spasm, the muscle alone is cut. A drain is placed,
and the wound is closed. A nasogastric tube may be placed for postop feeding. Aspiration precautions should be observed at both induction (consider awake intubation in severely symptomatic patients) and reversal of anesthesia, as this is a common comorbidity in patients with Zenker’s diverticulum. Endoscopic: Selected patients may be candidates for endoscopic treatment of a Zenker’s diverticulum. This is better described as diverticulotomy rather than diverticulectomy because the redundant hypopharyngeal mucosa is not removed, and the cricopharyngeus muscle is not divided in its entirety. Rather, the common wall separating the diverticulum from the esophagus is reduced to prevent food and debris from collecting within the confines of the diverticulum. With the patient under general anesthesia and muscle relaxation, an esophagodiverticuloscope is placed transorally and advanced into the hypopharynx. The endoscope is deployed to visualize clearly the opening into the diverticulum. The common wall separating the diverticulum from the true esophageal inlet is then cut, either with a stapler or with a CO2 laser.

Usual preop diagnosis: Dysphagia; Zenker’s diverticulum; cricopharyngeal spasm




ANESTHETIC CONSIDERATIONS

(See p. 184)




Suggested Readings

1. Aly A, Devitt PG, Jamieson GG: Evolution of surgical treatment for pharyngeal pouch. Br J Surg 2004; 9(6):657-64.

2. Dzeletovic I, Ekbom DC, Baron TH: Flexible endoscopic and surgical management of Zenker’s diverticulum. Expert Rev Gastroenterol Hepatol 2012; 6(4):449-65.

3. Feeley MA, Righi PD, Weisberger EC, et al: Zenker’s diverticulum: analysis of surgical complications from diverticulectomy and cricopharyngeal mytomoy. Laryngoscope 1999; 109(6):858-61.

4. Huang B, Payne WS, Cameron AJ: Surgical management for recurrent pharygoesophageal (Zenker’s) diverticulum. Ann Thoracic Surg 1984; 37(3):189-91.

5. van Overbeek JJ: Pathogenesis and methods of treatment of Zenker’s diverticulum. Ann Otol Rhinol Laryngol 2003; 112(7):583-93.


LARYNGEAL FRAMEWORK SURGERY (THYROPLASTY, ARYTENOID ADDUCTION, INJECTION LARYNGOPLASTY)


SURGICAL CONSIDERATIONS

Description: Thyroplasty is a surgical technique of medializing a paralyzed vocal fold via placement of an implant inserted through the cartilage of the thyroid ala. Under local anesthesia with intravenous sedation, a skin incision is made at the level of the larynx and the thyroid cartilage exposed. Using a small saw, drill bit, or knife, a window is cut in the cartilage to the level of the inner perichondrium. Lateral pressure is then applied to the paralyzed side to gauge the amount of medialization necessary to improve phonation. Because the shape and size of the implant is created based on the location and degree of medialization needed to improve the voice, it is important for the patient to be awake and able to phonate during the procedure. Often the patient is kept in a state of deeper sedation in the beginning of the case and then is lightened as the case proceeds to allow the patient to be responsive and interactive with the surgeon. This can be a challenge for the anesthesiologist to strike a happy medium between patient comfort and coherence. After the desired degree of medialization is obtained, the implant is secured in place and the wound closed over a drain.

Description: Arytenoid adduction is often performed in conjunction with thyroplasty. This involves placement of a suture around the muscular process of the arytenoid cartilage, which, when tightened, causes posteromedial rotation of the vocal process and adduction of the vocal fold. Usually the technique is employed when there is a persistent gap between the vocal folds posteriorly.

Description: Injection laryngoplasty refers to medialization of a paralyzed vocal fold by means of injection, whether percutaneous or endoscopic. Its minimally invasive nature is its chief advantage over thyroplasty or arytenoid adduction. However, the longevity of the injected material as well as its side effect profile are major determinants as to whether or not this procedure should be considered. Traditionally, Teflon was the injectable material of choice. However, because of the potential for a foreign body reaction, Teflon has been replaced by more biocompatible materials, such as acellular human dermis, fat, gelfoam, and calcium hydroxylapatite to name a few. Because of the low viscosity of some of these injectibles, many patients are candidates for percutaneous injection, which can be performed in the office or procedure room under simple topical anesthetic. The patient is seated upright and the nasal cavity topically anesthetized with lidocaine 2% and neosynephrine. A fiberoptic rhinolaryngoscope attached to a camera and television monitor is then passed transnasally to the level of the glottis. Through a 25- or 27-gauge needle, the desired material is injected either transcartilagenously, through the cricothyroid membrane, or under the thyroid ala into the paraglottic space. Observing on the monitor, the material is injected until the desired degree of medialization is obtained. This is well tolerated by patients with minimal pain. Airway obstruction or bleeding are exceedingly rare.

For those who request or require injection under GETA a 5.0 microlaryngeal tube is desirable. Jet ventilation and apneic techniques can also be used. An operating laryngoscope is advanced to the level of the glottis and suspended from a Mayo stand. The paryalyzed vocal fold is then injected, usually at the mid and posterior aspects, until adequate medialization is seen. Usually this entails slight overcorrection such that the medialized fold will now be slightly across midline. Hemostasis if needed is usually obtained with epinephrine-soaked pledgets placed directly on the vocal fold. The scope is then withdrawn and the procedure terminated.


It is important for the anesthesiologist to be aware if a patient has undergone a prior medialization procedure. This is not a contraindication to orotracheal intubation for subsequent procedures requiring GETA. However, traumatic intubation or the use of a tube larger than 6 mm may cause trauma to the adducted fold. A laceration of the vocal fold can potentially expose or dislodge a thyroplasty implant, making it more likely to become infected and potentially extrude.

Usual preop diagnosis: Vocal fold paralysis






Suggested Readings

1. Cotter CS, Avidano MA, Crary MA, et al: Laryngeal complications after type 1 thyroplasty. Otolaryngol Head Neck Surg 1995; 113(6): 671-3.

2. Damrose EJ, Berke GS: Advances in the management of glottic insufficiency. Curr Opin Otolaryngol Head Neck Surg 2003; 11(6):480-4.

3. Flint PW, Purcell LL, Cummings CW: Pathophysiology and indications for medialization thyroplasty in patients with dysphagia and aspiration. Otolaryngol Head Neck Surg 1997; 116(3):349-54.

4. Herman C: Medialization thyroplasty for unilateral vocal cord paralysis. AORN J 2002; 75(3):512-22.

5. Isshiki N, Morita H, Okamura H, et al: Thyroplasty as a new phonosurgical technique. Acta Otolaryngol 1974; 78(5-6): 451-7.

6. Isshiki N, Taira T, Tanabe M: Surgical alteration of the vocal pitch. J Otolarygnol 1983; 12(5):335-40.

7. Isshiki N, Tsuji DH, Yamamoto Y, et al: Midline lateralization thyroplasty for adductor spasmodic dysphonia. Ann Otol Rhinol Laryngol 2000; 109(2):187-93.

8. Pou AM, Carrau RL, Eibling DE et al: Laryngeal framework surgery for the management f aspiration in high vagal lesions. Am J Otolaryngol 1998; 19(1):1-7.

9. Weinman EC, Maragos NE: Airway compromise in thyroplasty surgery. Laryngoscope 2000; 110(7):1082-5.


ANESTHETIC CONSIDERATIONS


PREOPERATIVE

The laryngeal framework surgery (LFS) is the surgery of choice for dysphonias resulting from incomplete glottic closure or inadequate vocal fold tension. With thyroplasty, direct surgery on the vocal folds is avoided, eliminating the possibility of scarring and voice aggravation. Type I (medialization) thyroplasty is most commonly performed for the unilateral VC paralysis or bowing (in elderly patients), and involves placement of a small silicon implant within the larynx on the affected side.























Airway


No airway problems are usually encountered in these patients.


Cardiovascular


Elderly patients may present with advanced cerebrovascular, cardiovascular, or pulmonary disease. Preop pulmonary aspiration due to glottic incompetence is uncommon, but may be seen when the VC paralysis is of central origin, affecting both motor and sensory components of the VC innervation.


Tests


EKG; other tests as indicated from H&P


Laboratory


Tests, as indicated from H&P


Premedication


Standard premedication with iv midazolam can frequently be reduced or avoided, especially in the elderly.



INTRAOPERATIVE

Anesthetic technique: Most commonly, thyroplasty is performed under MAC, which allows the surgeon to achieve optimal improvement in the patient’s voice quality (sometimes facilitated by visualization of the VC movement through a nasally introduced flexible fiberoptic endoscope) before locking the laryngeal implant in place. It can also be performed under GA, when the concomitant use of the LMA and flexible fiberoptic bronchoscope allows a real-time assessment of VC positioning. Arytenoid adduction and injection laryngoplasty are usually performed under GETA with the use of a small (5.0 mm ID) MLT ETT.

The essential surgical requirements for thyroplasty performed under MAC include patient immobility for an effective injection of a local anesthetic; alternating levels of MAC sedation, depending on the part of the surgery (deep level of sedation during the surgical approach to the cartilage, light for the implant placement, and deep again during the surgical closure); absence of straining/bucking/coughing during the implant placement and manipulation on the thyroid cartilage necessitates the use of iv opioids.

GETA for arytenoid adduction and injection laryngoplasty requires full muscle relaxation with quick return of protective airway reflexes and smooth emergence from anesthesia.

When providing MAC for thyroplasty, a quick patient transition to the “light” state for the implant placement is required. A combination of a small dose (1-2 mcg/kg) of iv fentanyl with the iv propofol infusion, or iv midazolam
with iv remifentanil infusion (typically, 0.05-0.1 mcg/kg/min to avoid severe respiratory depression), will achieve the stated objective. For a thyroplasty performed under GA, as well as for the GETA employed for a arytenoid adduction and injection laryngoplasty surgery, the use of TIVA (see Introduction, Anesthesiologist’s Perspectives, p. 178) has been shown to be highly beneficial. Injection laryngoplasty procedures can be very short and, if properly coordinated with the surgeon, can occasionally be performed without tracheal intubation, using an apneic technique following full preoxygenation, iv induction, administration of a relatively large dose of succinylcholine (1.5-2 mg/kg) and brief mask hyperventilation with FiO2 = 1.0.
























Blood and fluid Requirements


IV: 20 ga × 1


LR @ 2 cc/kg/h


EBL is minimal during all the LFS procedures.


Monitoring


Standard monitors (p. B-1)


± arterial line


Even in patients with preexisting significant CV disease, A-line monitoring is usually not necessary.


Positioning


Table may be turned 90-180°


[check mark] and pad pressure points


[check mark] eyes


To prevent claustrophobia, inform the patient presenting for thyroplasty under MAC that his/her face will be partially covered with surgical towels.


Complications


Overmedialization


Stridor and dysphonia


Can be quickly corrected by the surgeon



POSTOPERATIVE














Complications


Wound hematoma


Airway obstruction


Stridor


Extrusion of the prosthesis


Pain management


Short-acting parenteral opioids


(p. C-1) are usually sufficient.




Suggested Readings

1. Grundler S, Stacey MR: Thyroplasty under general anesthesia using a laryngeal mask airway and fibreoptic bronchoscope. Can J Anaesth 1999; 46(5Pt1):460-3.

2. Hoffman H, McCabe D, McCulloch T, et al: Laryngeal collagen injection as an adjunct to medialization laryngoplasty. Laryngoscope 2002; 112(8 Pt1):1407-13.

3. Lundy DS, Casiano RR, Xue JW: Can maximum phonation time predict voice outcome after thyroplasty type I? Laryngoscope 2004; 114:1447-54.

4. Razzaq I, Wooldridge W: A series of thyroplasty cases under general anaesthesia. Br J Anaesth 2000; 85:547-9.

5. Remacle M, Lawson G, Jamart J, et al: Treatment of vocal fold immobility by injectable homologous collagen: short-term results. Eur Arch Otorhinolaryngol 2006; 263:205-9.

6. Remacle M, Lawson G, Mayné A: Use of a laryngeal mask during medialization laryngoplasty. Rev Laryngol Otol Rhinol (Bord) 2003; 124:335-8.


TRACHEAL AND CRICOTRACHEAL RESECTION


SURGICAL CONSIDERATIONS

Description: Prolonged endotracheal intubation and complications from tracheotomy account for most cases of subglottic or tracheal stenosis. Wegener’s disease commonly affects the subglottic airway, and secondary dyspnea may be the first presenting sign of the disease. In females in the 4th to 6th decades of life, subglottic stenosis can be idiopathic. Whatever the etiology, subglottic and tracheal stenosis can be a major source of morbidity for afflicted
patients, resulting in dyspnea, dysphonia, and tracheostomy dependence. In selected individuals, resection of the stenotic region with primary repair can often produce marked and sustained relief of symptoms in a single-stage procedure, often without need for a temporary tracheostomy.

Tracheal resection is the treatment of choice in patients with isolated tracheal stenosis. Up to four to five rings of cartilage can be resected, more if releasing maneuvers to mobilize the larynx and intrathoracic trachea are performed. Induction of anesthesia is simplest in patients with preexisting tracheostomies. For those patients who present without a tracheostomy, a tracheostomy under local anesthesia can be performed at or immediately below the stenotic segment. If possible, it is preferable to dilate the stenosis and proceed to endotracheal intubation to avoid further injury to the trachea with a fresh tracheotomy. With the patient in the supine position, a transverse cervical incision is made. The thyroid isthmus is divided and separated from the cervical trachea. Careful blunt dissection on the lateral aspects of the diseased segment is performed to avoid injury to the recurrent laryngeal nerves. A vertical incision is made along the face of the stenotic segment until a healthy complete ring of cartilage is identified above and below the stenotic segment. The anesthesiologist withdraws the ETT up into the subglottis, and the diseased segment of trachea is resected. At this time, the surgeon may intubate the distal segment of trachea to afford better access to the superior aspect of the diseased segment. In this case, the breathing circuit will need to be switched from the orotracheal tube to the distal tube. The distal trachea can be more easily mobilized superiorly following blunt finger dissection along the anterior tracheal wall into the mediastinum. The orotracheal tube is then advanced inferiorly into the distal healthy segment. The healthy distal and proximal segments of trachea are then reanastomosed over the ETT using interrupted sutures. The wound is closed and a drain placed. If the patient is to remain intubated overnight, it is important to ensure that the cuff of the endotracheal tube remains inferior to the suture line so as not to put tension on the repair. If the patient is to be extubated in the OR, care should be taken to minimize coughing or bucking so as not to rupture the repair site. Endoscopy can be performed prior to transport from the operating room to ensure that at least one vocal fold is mobile. If neither vocal fold is mobile, a bilateral recurrent laryngeal nerve injury should be suspected and a tracheostomy performed. Regardless of whether or not the patient is extubated immediately or later, fiberoptic laryngoscopy to assess vocal fold motion postop is standard of care. Voice quality is not an adequate assesment of vocal fold function. A paralyzed vocal fold can be midline with complete compensation by the mobile fold and no overt dysphonia. In bilateral vocal fold paralysis, the voice is often normal, and the patient’s only symptoms will be dyspnea and stridor.

Cricotracheal resection allows single-stage repair of subglottic or a combined subglottic/tracheal stenosis. The procedure is similar to that of tracheal resection with several caveats. It is important to carefully gauge the relationship of the stenosis to the vocal folds. Stenosis that involves the vocal folds is a contraindication to cricotracheal resection. The anterior arch of the cricoid cartilage is usually resected, along with the subglottic soft tissue component of the stenosis, preserving the cricoid plate. This creates a cradle into which the trachea will slide superiorly. No more than one-third of the inferior aspect of the cricoid plate can be resected. More than this will disrupt the posterior cricoarytenoid muscles and prevent vocal fold abduction during inspiration. As resection proceeds, the ETT will be withdrawn above the glottis. It is helpful at this point to attach an umbilical tape to the distal tip of the ETT to allow the surgeon to assist the anesthesiologist in advancing the tube back through the glottis and into the trachea when the resection is complete. The trachea is sutured to the thyroid cartilage anteriorly and the cricoid ring laterally; the wound is closed; and a drain may be placed. The patient is extubated in the OR and vocal fold mobility checked. Tracheostomy is only required in the setting of bilateral vocal fold paralysis and should otherwise be avoided. As with tracheal resection, a preop assesment of vocal fold motion is critical in planning surgery. If unilateral paralysis is present preop, great care is needed to minimize potential injury to the contralateral recurrent laryngeal nerve.

Usual preop diagnosis: Subglottic stenosis; tracheal stenosis






Suggested Readings

1. Brown BR: Anaesthesia for ear, nose, throat and maxillofacial procedures. In: Prys-Roberts C, Brown BR, eds. International Practice of Anaesthesia. Butterworth-Heinemann, Oxford: 1996, 2-9.

2. Chee WK, Benumof JL: Airway fire during tracheostomy: extubation may be contraindicated. Anesthesiology 1998; 89:1576-8.

3. Feldman MA, Patel A: Anesthesia for eye, ear, nose, and throat surgery. In: Miller RD, ed. Miller’s Anesthesia, 7th edition. Elsevier, Philadelphia: 2010, 2357-88.

4. Hobai IA, Chhangani SV, Alfille PH: Anesthesia for tracheal resection and reconstruction. Anesthesiol Clin 2012; 30(4): 709-30.

5. McGuire G, El-Beheiry H, Brown D: Loss of the airway during tracheostomy: rescue oxygenation and re-establishment of the airway. Can J Anesth 2001; 48:697-700.

6. Rogers ML, Nickalls RWD, Brackenbury ET, et al: Airway fire during tracheostomy: prevention strategies for surgeons and anaesthetists. Ann R Coll Surg Engl 2001; 83:376-80.



LARYNGECTOMY: PARTIAL AND TOTAL


SURGICAL CONSIDERATIONS

Description: Either radiation, chemoradiation or surgery is commonly employed as primary treatment of laryngeal squamous cell carcinoma. Selected tumors can be removed endoscopically, as reviewed above. Open procedures, which may be primary or following recurrence after irradiation, are designed to fit tumor extent. If at least one cricoarytenoid unit (innervated posterior cricoarytenoid muscle and working cricoarytenoid joint) is uninvolved by tumor, the patient may be a candidate for less than a total laryngectomy.

A vertical partial laryngectomy (VPL) involves removal of the affected true and false vocal folds, and up to one-third of the contralateral folds including the anterior commissure. The contralateral cricoarytenoid unit is preserved, and reconstruction often includes a pedicled sternohyoid flap as well as thyroid cartilage perichondrium. Exposure and anesthetic considerations are similar to that of a total laryngectomy (discussed below) other than the fact that a temporary tracheotomy is used in the partial laryngectomy.

A supraglottic laryngectomy (Figs. 3-4 and 3-5) or anterior horizontal partial laryngectomy (AHPL; Fig. 3-6) involves removal of laryngeal structures superior to the true vocal cords. Both cricoarytenoid units remain. The resection may include some of the base of tongue. Exposure and anesthetic considerations are the same as for for a VPL, including the need for a temporary tracheotomy.

A supracricoid laryngectomy involves removal of the larynx from the top of the cricoid ring to the hyoid bone with preservation of at least one arytenoid. A temporary tracheostomy is required. Cuts are made above the thyroid ala, through the cricothyroid membrane, and anterior to the arytenoid cartilages. The epiglottis may be included in the resection if necessary, depending upon the extent of the tumor. Blunt finger dissection anterior to the trachea into the mediastinum is performed to allow for superior mobilization of the trachea. A cricohyoidopexy, involving the suturing of the cricoid ring to the hyoid bone, is then performed with three heavy sutures. If the epiglottis has been preserved, a cricohyoidoepiglottopexy is performed. The strap muscles are then used to reinforce the closure, and drains are placed.






Figure 3-4. The larynx is viewed from the midline, as seen by the surgeon standing at the head of the operating table. Unless the lesion extends posteriorly to the arytenoid, the aryepiglottic fold is transected on each side by placing one blade of the dissecting scissors into the laryngeal ventricle or above the false vocal cord and the other blade in the pyriform sinus. The arytenoid on one side can be resected if the tumor extends posteriorly to involve this structure. (Reproduced with permission from Montgomery WW: Surgery of the Upper Respiratory System, 3rd edition. Williams & Wilkins, Baltimore: 1996.)







Figure 3-5. The repair following supraglottic partial laryngectomy begins by carefully approximating the margin of the mucous membrane of the pyriform sinus to the lateral margin of the laryngeal ventricle, or to the margin of resection above the false vocal cord. There is usually some distortion of the true vocal cord when the repair is accomplished, as is shown on the patient’s right side. The repair is continued anteriorly by placing multiple interrupted 3-0 chromic catgut sutures. (Reproduced with permission from Montgomery WW: Surgery of the Upper Respiratory System, 3rd edition. Williams & Wilkins, Baltimore: 1996.)






Figure 3-6. A: Horizontal incisions, corresponding to the mucosal incision, are made through the thyroid lamina. B: The specimen—including true and false vocal cords, the arytenoid, and a portion of the thyroid lamina—is resected en bloc. (Reproduced with permission from Montgomery WW: Surgery of the Upper Respiratory System, 3rd edition. Williams & Wilkins, Baltimore: 1996.)


A total laryngectomy (TL) involves the resection of the entire larynx and can be done via an incision about 8 cm long, low in the midline neck. An apron incision is often used instead, or the low incision is extended toward a mastoid tip to provide exposure for a neck dissection if indicated. The thyroid gland is often preserved, pedicled on its superior and inferior vasculature after dividing the isthmus; but if indicated a partial thyroidectomy may be included. The thyoid is resected with the specimen and the pharynx closed primarily. A nasogastric tube is used for nutrition for all open laryngeal tumor surgery, unless the surgeon opts to provide nutrition via a tracheoesphageal puncture, discussed below. As the remaining trachea is sutured to the anterior skin in a true tracheostoma, no tracheotomy tube or ETT is required postop unless there is marked stomal edema or mechanical ventilaton is required, which is not common.

If a TL is performed, a tracheoesphageal puncture (TEP) may be performed simultaneously. This involves the creation of a tract or fistula between the trachea and the esophagus for placement of a voicing prosthesis (a one-way valve that allows airflow from the trachea into the pharynx for alaryngeal speech). The voicing prosthesis may be placed at the time of the laryngectomy or as a secondary procedure at a later date. If performed secondarily, it is placed using the technique of rigid esophagoscopy (see previous section). If TEP is performed at the time of laryngectomy, the valve can be placed simultaneously. Some surgeons prefer to place a red rubber catheter instead, which can allow the patient to be fed via this route in lieu of a nasogastric or gastrostomy tube. After the patient is deemed fit to start oral intake, the catheter can be exchanged secondarily for the voice prosthesis. If a rubber catheter is used, the tube will protrude from the stoma, and care must be taken not to dislodge it during suctioning or while removing or replacing the laryngectomy tube if one is temporarily used during the period of postop edema.

A TL can be extended to include part of the hypopharyx or oropharynx as dictated by tumor extent. If flap reconstruction is necessary because of the extent of the tumor, options include use of a pectoralis major myocutaneous flap or a free flap, such as a radial free flap, to reconstruct less than a circumferential defect. If a circumferential defect following resection exists (e.g., after resection of the superior cervical esophagus and the larynx), options for reconstruction include use of a laparascopically harvested jejunal free flap, gastric pullup, or a tubed radial free flap reinforced with a pectoralis major myogenous flap.

Postop care: Inpatient admission for 5-10 d; monitored bed or ICU for tracheostomy care or following more extensive pharyngeal reconstruction; a cuffed tracheostomy tube (and a temporary tracheotomy) will usually be required for partial laryngectomy patients or if the patient will require postop mechanical ventilation. A shorter tracheostomy tube following a TL will be needed if there is significant peristomal edema or if mechanical ventilation is required. General and drain management is similar to a neck dissection.

Usual preop diagnosis: Cancer of larynx; intractable aspiration with resultant pneumonia unresponsive to other techniques

Only gold members can continue reading. Log In or Register to continue

May 23, 2016 | Posted by in ANESTHESIA | Comments Off on Otolaryngology—Head and Neck Surgery

Full access? Get Clinical Tree

Get Clinical Tree app for offline access