eMedicine - Surgical Management of Chronic Aspiration : Article by Mark E Gerber

You are in: eMedicine Specialties > Otolaryngology and Facial Plastic Surgery > LARYNGOLOGY

Surgical Management of Chronic Aspiration

Article Last Updated: Jun 9, 2006

The interplay of several complex mechanisms is required to achieve a balance in the physiologic functioning of the upper aerodigestive tract. When these mechanisms are in optimal functional capacity, voluntary and involuntary neuromuscular control allows the individual to perform the acts of phonation, respiration, swallowing, and airway protection. These functions are critical to the sustained well-being of the individual, and a breakdown of any of these functional areas can produce disease with resultant morbidity and mortality. Once medical management fails, surgical options may be considered as a lifesaving intervention.

History of the Procedure

The surgical management of chronic aspiration is based on the concept of the shared upper airway for the functions of swallowing and respiration. Before 1972, laryngectomy was routinely chosen to separate these functions in the setting of chronic aspiration. This practice was considered less than ideal because voice and supraglottic respiration are lost. Further, the procedure is irreversible.

In 1972, Habal and Murray described a laryngeal closure procedure in one patient that involved creation of an epiglottic flap to close the larynx. In 1975, Lindeman described his experience with a reversible technique in which he diverted the larynx to the esophagus and the trachea to the neck as a stoma in a canine model. He subsequently performed this procedure on a patient with a paralyzed larynx. Modifications have been described (eg, laryngotracheal separation [LTS]), including several by Lindeman.

Since then, as diagnostic and therapeutic techniques have become more sophisticated, more specific procedures have been developed to address specific pathology. These procedures included laryngeal-specific techniques, such as vocal cord medialization, total/partial cricoidectomy, and laryngeal suspension. Alimentary procedures, such as feeding gastrostomy and jejunostomy, cricopharyngeal myotomy, and gastric fundoplication, are also useful. Chronic aspiration of excessive oropharyngeal secretions may be controlled via surgical control of salivation.

Problem

Chronic aspiration is defined as recurrent episodes of liquid or solid materials that pass below the level of the vocal cords. Surgery is indicated when intractable aspiration with life-threatening sequelae does not respond to conservative medical management.

Etiology

The etiology of chronic aspiration is multiple and reflective of the functions of the larynx in airway protection, swallowing, phonation, and respiration. A disorder that has an effect on neurologic control, muscular strength, or local anatomy of the upper aerodigestive tract can affect these functions with resultant chronic aspiration.

In the adult population, the most common etiology is neurologic sequelae from a stroke (infarct or hemorrhage). In this circumstance, aspiration is usually secondary to the loss of cough and swallow reflexes. Closed head injuries, anoxic encephalopathy, and CNS depression due to intoxication may also produce aspiration.

Degenerative neurologic diseases (eg, multiple sclerosis, Parkinson disease, amyotrophic lateral sclerosis), neuromuscular diseases (eg, myasthenia gravis, muscular dystrophies), and peripheral neuropathies (eg, cranial nerve disorders, Guillain-Barré syndrome) can result in chronic aspiration.

Neurogenic aspiration is commonly differentiated into lower and upper motor neuron etiology. Upper motor neuron pathology presents with aspiration that is characterized as straining or strangling in nature; whereas, lower motor neuron disease is associated with flaccid paralysis and aspiration of liquids. Intracranial complications of infection and/or neoplasms may produce aspiration due to neurologic devastation, either directly or from treatment (ie, radiation, surgery).

Pharyngeal and esophageal disorders, such as laryngopharyngeal and gastroesophageal reflux, cricopharyngeal spasm, strictures, Zenker diverticulum, achalasia, and postradiation/postsurgical changes for neoplastic processes, may result in aspiration.

Lastly, the pediatric population may have aspiration as a result of congenital anatomic abnormalities, such as laryngeal clefts and tracheoesophageal fistulas, as well as sialorrhea and many of the previously noted etiologies (Eisele, 1998).

Pathophysiology

Aspiration is not always a pathologic process. A small amount of aspiration is normal. When the normal mechanisms for airway clearance (ie, coughing, cilia) are present, they protect the airway from complications.

Pathologic aspiration is marked by pulmonary complications (eg, aspiration pneumonitis/pneumonia). A breakdown in airway clearance mechanisms and/or in respiration, phonation, or swallowing mechanisms can result in pathologic aspiration. The pathologic processes responsible for the breakdown of these mechanisms have been previously discussed.

Clinical

The clinical presentation of chronic aspiration is variable and nonspecific. Clinical symptoms suggestive of chronic aspiration include choking, coughing, fever, dyspnea, dysphonia, frequent throat clearing, chest pain, dysphagia, odynophagia, tachypnea, wheezing, rales, and emesis. The pediatric population may have many of these symptoms, as well as stridor, failure to thrive, apneic episodes, and regurgitation of feedings. Further, the presentation of chronic aspiration may be so-called silent aspiration with no presenting symptoms or signs until complications develop.

Surgical intervention for intractable aspiration is indicated when life-threatening complications ensue and conservative measures do not adequately control episodes of aspiration.

The upper aerodigestive tract (from the oropharynx to the larynx) allows for separating the various functions of these areas while also coordinating them. These functions are respiration, phonation, swallowing, and airway protection via cough reflexes/ciliary clearance.

The pertinent anatomy and physiology of the oropharynx is related to its function in speech and swallowing. The borders of the cheeks and lips define the mouth. The interior of the mouth contains the dentition, mucosa, salivary gland apertures, and tongue. The hard and soft palate forms the roof of the mouth. The most posterior portion of the soft palate or velum is extremely important in preventing the nasopharyngeal reflux during swallowing. The anterior and posterior muscular pillars formed by the palatoglossus and palatopharyngeus muscles (which form the tonsillar fossa) are important functional and anatomic landmarks.

The pharynx is bordered by mucosa that covers the constrictor muscles of the oropharynx and the hypopharynx. The larynx is bounded superiorly by the upper tip of the epiglottis and inferiorly at the lower border of the cricoid cartilage. The laryngeal mucosa is draped over a cartilaginous framework, which includes the epiglottis, the aryepiglottic folds, the false vocal folds, the cuneiform, corniculate and arytenoid cartilages, and the true vocal folds (which include the vocalis muscles and membranous coverings). The major cartilaginous framework, from superiorly to inferiorly, is the thyroid cartilage (which houses the glottis proper) and the cricoid cartilage. The hyoid bone also serves as an attachment to which the larynx is suspended.

Deglutition is a complex act that is under both voluntary and involuntary neural controls. Swallowing is typically divided into 4 stages. The first 2 stages are under voluntary control, except in the newborn period when the swallowing reflex is regulated at the level of the brain stem. The second 2 stages are reflex actions. The afferent limb of this reflexive action consists of sensory and proprioceptive fibers in the glossopharyngeal, trigeminal, and superior laryngeal nerves that supply the laryngeal and pharyngeal mucosa. Impulses are transmitted to the swallowing center in the floor of the fourth ventricle. The efferent limb consists of general visceral efferent fibers that begin in the nucleus ambiguous and descend through the vagus nerve to supply the laryngeal and pharyngeal musculature.

The preparatory phase consists of the ingestion of food into the mouth and the formation of a food bolus after chewing and salivary mixing. The bolus is held between the hard palate and anterior two thirds of the tongue, while the tongue base and soft palate act to close the pharynx until the bolus is fully prepared.

The oral phase begins with the elevation of the anterior tongue as it meets the hard palate and the food bolus is pushed posteriorly into the pharynx. The preparatory and oral phases are under voluntary control. Once the anterior tonsillar pillar is met, the pharyngeal phase is initiated. The pharyngeal constrictors, the palatopharyngeus, and the closed velum interact to essentially squeeze the bolus down the pharynx and the hypopharynx toward the esophagus.

Once the esophageal phase begins, respiration ceases with laryngeal closure; the epiglottis, aryepiglottic folds, false vocal folds, and true vocal folds close. Concomitantly, the soft palate meets the posterior pharyngeal wall in the nasopharynx, thus closing the nasopharynx during the swallow. The cricopharyngeus muscle relaxes, and esophageal peristalsis completes the swallow.

The cough reflex is mediated via the sensory receptors of the airway located within the respiratory epithelium from the larynx to the terminal bronchioles. The medullary cough centers control the reflex with afferent and efferent limbs of the reflex via cranial nerve X and, to a lesser extent, cranial nerves V and IX.

Cough can be voluntarily initiated without stimulation from other afferent pathways. The efferent fibers of the cough reflex leave the medullary cough center through the phrenic and spinal motor nerves to the diaphragm and intercostal muscles, respectively. The abdominal and pelvic muscles also participate in the efferent limb. The cough mechanism is initiated with a rapid, high-volume inspiration via maximally abducted vocal cords and intrathoracic expansion. This results in a high-pressure gradient once the vocal cords adduct, the supraglottic larynx closes, and the expiratory muscle contracts. This compressive coughing is primarily mediated through the closure action of the false vocal folds, which act as a sphincter. Finally, the glottis opens, accompanied by expiration of a high-pressure air column that carries expectorated materials from the airway (Hollinshead, 1985).

Contraindications to surgical intervention for chronic aspiration are procedure specific and are discussed with each procedure. Generalized surgical contraindications include bleeding diatheses, anesthetic contraindications, poor pulmonary reserve, and/or expectation of return of normal function.

Imaging Studies

Diagnostic Procedures

Medical therapy

Medical therapy frequently requires the interdisciplinary cooperative efforts of medicine, otolaryngology, gastroenterology, speech therapy, radiology, physiatry, and neurology specialists.

Usually, the first step in the medical management of chronic aspiration is the treatment of bronchopulmonary complications (eg, pneumonia). This treatment may entail antibiotic therapy that covers anaerobic and pseudomonal species and intubation for ventilatory support and intensive care. Once the patient stabilizes, the severity, source, pathologic etiology, and chronicity of the aspiration is determined.

Until a swallowing evaluation is completed, allow the patient nothing by mouth (NPO). Consider alternative methods of alimentation that use the gut (when functional). Methods include gastrointestinal feeding tubes via the nose or mouth and percutaneous gastrostomy or jejunostomy. Since alimentary feeding tubes do not eliminate the risk of aspiration (as with orogastric/nasogastric tubes) and actually may increase the aspiration by elimination of the protective action of the esophageal sphincters, reflux precautions must be strictly followed. Reflux precautions include placing the bed in a high Fowler position, especially during and after feedings; maintaining slow drip rather than rapid bolus feedings (or small frequent feedings); and administering medication.

Antiemetics, H2 antagonist, and proton pump inhibitors are frequently used. Hyperalimentation may be used in individuals who are not alimentary feeding candidates. Pursue aggressive pulmonary toilet (including frequent suctioning) in both intubated and nonintubated patients with aspiration.

Surgical therapy

Tracheotomy

Tracheotomy is indicated in both chronic aspiration and pulmonary complications requiring sustained ventilatory support. This procedure is also indicated in relief of upper airway obstruction, in prolonged need for ventilatory support, obstructive sleep apnea, and pulmonary hygiene.

A tracheotomy does not prevent aspiration. In 1999, Schonhofer et al reported a 30% aspiration rate in patients who were tracheotomized. The presence of a tracheotomy tube can increase aspiration risk via limitation of laryngeal elevation and anterior-superior excursion during swallowing (Strome, 1996). A cuffed tracheotomy tube further increases this risk and the risks of mucosal ulceration, tracheal stenosis, and chondritis. These risks have been minimized with the advent of high-volume, low-pressure cuffs.

After achieving an adequate level of endotracheal general anesthesia, the patient is positioned with the neck extended and a shoulder roll placed underneath. The patient is then prepared and draped in a sterile fashion. Local anesthetic containing epinephrine is injected along the proposed incision site.

An incision is made either vertically in the midline or horizontally in a skin fold at the level of the second to third tracheal ring. (This may be approximated by placing the incision 1 cm above the suprasternal notch in adults.) The incision is carried through the skin, subcutaneous tissue, and platysma muscle to the level of the strap muscles. The anterior jugular veins are identified and retracted; however, they may be ligated, if needed. The midline raphe of the strap muscles is identified and split vertically. The strap muscles are retracted laterally. The thyroid isthmus is either retracted or divided and ligated with running 2-0 silk sutures bilaterally.

At this point, the anterior trachea is visualized, and a tracheal hook is used to steady the trachea at the second tracheal ring. An incision is made between the second and third tracheal rings, and the anterior portion of the third or fourth tracheal ring is removed. Alternatively, an inferiorly or superiorly based flap consisting of the ring is sutured to the skin with a nonabsorbable suture. In children, a vertical incision is made in the second and third or third and fourth tracheal rings. Traction sutures are then placed at the edge of the incision and sutured to the skin.

At this juncture, the endotracheal tube is withdrawn, and a tracheotomy tube is inserted. The tracheotomy tube is appropriate to both the patient's age and the size of the trachea. It is fastened to the patient using tracheotomy tape with a finger breadth of room under the tie. Foam padding may be placed under the ties to prevent skin breakdown. Alternatively, the tracheotomy plate can be sutured to the skin with a nonabsorbable suture.

Complications include wound infection, bleeding, hematoma, tracheotomy tube plugging, and pneumothorax.

For postoperative care, ensure that tracheotomy cleaning, dressing changes, and frequent suctioning for the first 24 hours following surgery are accomplished. Additionally, ensure that the postoperative caregiver is educated regarding tracheotomy care and cleaning.

Laryngectomy

Laryngectomy was once the mainstay of surgical intervention for aspiration; however, the loss of phonation, laryngeal respiration, and irreversibility of the procedure has currently limited its application. Billroth performed the first laryngectomy in 1873 for laryngeal carcinoma (Chas, 1985). In 1990, Dedo, who no longer performs LTS for aspiration because reconnection was not accomplished in his hands, stated that the inability of patients who underwent LTS to phonate and the inability to insert voice prosthesis were considerations in his decision to return to laryngectomy for treatment of aspiration.

Laryngectomy is indicated in life-threatening aspiration that follows surgical excision of head and neck tumors (especially of the oropharynx) and in severe neurologic conditions that impair swallowing. Other indications include T3 or T4 tumors of the larynx (ie, with cord fixation and/or transglottic carcinomas).

Contraindications to laryngectomy include good prognosis of neurologic recovery and swallowing ability, as well as T1 and T2 tumors of the larynx.

The first decision in preparing a patient for laryngectomy for chronic aspiration is to choose an incision type. The apron flap incision (which incorporates the previous tracheostomy stoma) is commonly used as a tracheotomy and is often performed in patients with chronic aspiration. The incision starts from the mastoid tip to the level of the stoma, then curves upward to the contralateral mastoid tip following the edge of the sternocleidomastoid (SCM) muscle for the vertical portion and a natural skin crease at the horizontal anterior neck portion. The skin flaps are then elevated in the subplatysmal plane.

In general, a narrow field of resection is performed, and the hyoid, strap musculature, and the hypopharyngeal mucosa are preserved (Wisdom, 1997). The larynx is skeletonized after separation of the strap muscles in the midline and division with ligation of the thyroid isthmus. Following this step, the thyroid is released from the ligamentous attachments to the larynx and the trachea.

The posterior border of the thyroid cartilage is exposed, and the inferior constrictor muscle attachment to the thyroid cartilage is identified. Subsequently, the attachment is released along the ala of the thyroid cartilage. The superior laryngeal nerve with accompanying artery and vein are ligated and divided bilaterally. The superior horn of the thyroid cartilage is identified, and the piriform sinus mucosa is dissected free of the thyroid cartilage bilaterally. The thyrohyoid membrane is incised along the inferior border of the hyoid, and the larynx is mobilized. The trachea is transected at the level of the previous stoma, and the posterior trachea along with the cricoid cartilage is carefully separated from the esophagus. The anterior wall of the distal tracheal segment is then sutured to the skin with a heavy suture, and an armored tube is placed.

The pharynx is entered via the piriform sinus or the vallecula. Alternatively, the pharynx may be entered at the arytenoids, with a limited infrahyoid pharyngotomy performed. This allows preservation of the pharyngeal mucosa in vallecula, aryepiglottic, and postcricoid areas. However, the classic incision is carried along the walls of the sinuses medially and along the vallecula and epiglottis superiorly. Once the level of the cricoid cartilage is reached, the incisions are joined (ie, superior and inferior incisions), and the larynx is removed. The pharynx is then closed using an inverted running-type Connell stitch with 3-0 Vicryl over a nasogastric tube. The constrictor muscles are sutured in a similar fashion to provide for a second-layer closure.

Suturing the skin edges to the tracheal mucosa without tension forms the permanent tracheostome. This may require defatting of the adjacent skin and/or subcutaneous tissue. Lastly, the wound is closed in layered fashion with reapproximation of platysmal, subcutaneous, and epidermal layers. If a tracheotomy was originally present in the skin flap, excision of the scarred tissue is required, and the defect is repaired as meticulously as possible.

Complications include pharyngocutaneous fistula, infection, stomal stenosis, and subcutaneous hematoma.

For postoperative care, the wound drainage is monitored. Drains are discontinued when minimal drainage is noted. Wounds are covered with topical antibiotic ointment. Sutures are removed in 7-10 days. Care of the tracheostome is as previously noted. Systemic antibiotics are administered postoperatively for 3 doses. Prior to discharging the patient from the hospital, methylene blue or radiographic swallow studies may be performed to exclude subclinical pharyngeal or esophageal leakage.

Phonation may be restored postoperatively with minimal aspiration risks by using the Blom-Singer prosthesis via tracheoesophageal puncture.

In 1997, Krespi and Blitzer reported on 10 patients who were treated with this technique after other procedures had failed for aspiration; this technique was successful in all 10 patients.

Laryngeal suspension

Suspension of the supraglottic laryngeal structures may be performed. Laryngeal suspension allows for easier swallowing via a wider hypopharynx and guards against glottic penetration during swallowing. This procedure allows the continuance of normal respiration, phonation, and swallowing.

Indications for laryngeal suspension include aspiration following supraglottic and/or hypopharyngectomy.

Contraindications to laryngeal suspension include life-threatening aspiration. (This procedure is usually performed in conjunction with supraglottic laryngectomy and/or hypopharyngectomy.)

The anterior neck is prepared and draped in a sterile fashion. The skin is incised at the level of the thyroid cartilage and is carried to the platysma. Subplatysmal flaps are then carried to the level of the thyroid cartilage and the anterior border of the mandible.

The strap muscles are identified and dissected in the midline until the thyroid cartilage is identified. The mandibular symphysis is then identified. A drill is used to bore a hole at the symphysis. A wire can be used to suspend sutures, or they may be placed directly in the hole. Three 3-0 nylon sutures are passed along the superior edge of the thyroid cartilage and periosteum; 1-2 sutures are also placed at the inferior edge of the cartilage. An anterosuperior displacement of the larynx and a widening of the hypopharynx occur as the sutures are tightened. Closure of the neck is in a standard layered fashion (Lore, 1988).

Following surgery, patients should be observed for aspiration; swallow studies can be performed to delineate silent aspiration. In addition, patients should receive wound care and 3 doses of postoperative antibiotics.

Total and partial cricoid resection

Partial cricoid resection is usually performed as an adjunct during reconstruction of the oropharynx after tumor resection. In 1993, Cummings proposed subperichondrial cricoidectomy instead of laryngectomy.

Indications for this procedure include chronic aspiration with poor or no chances of recovery.

Contraindications to total or partial cricoid resection include good prognosis for neurologic recovery or return of swallowing capability.

For a total cricoidectomy, the patient is prepared in a similar fashion to that of a tracheotomy (see Tracheotomy). A midline neck incision or an apron incision is performed to the level of the strap muscles and the trachea. The tracheostome is performed, as previously described, and the cricoid ring is identified. The cricoid is incised anteriorly and is grasped with skin hooks. The cricoid cartilage is then removed after elevation of the cartilage in the subperichondrial plane. The inner perichondrium is closed, and the mucosa is sutured after infolding the cut ends. The sternohyoid muscle is placed between the proximal and distal stumps, and the outer perichondrium is closed. Neck closure is performed in a layered fashion, as previously described (Cummings, 1993).

Partial cricoidectomy is approached as described above, except only a submucosal segment of the posterior cricoid cartilage is resected and a cricopharyngeal myotomy is performed.

Complications include pharyngotracheal fistula, wound infection, bleeding, hematoma, and pneumothorax.

Postoperative care is similar to that following a tracheotomy (see Tracheotomy). Adequate wound care must be provided. Sutures are removed in 7-10 days. Antibiotics are administered postoperatively for 3 doses.

Vocal fold medialization

This procedure is used in the setting of aspiration secondary to unilateral paralysis or atrophy of the vocal folds. Isshiki popularized the procedure in 1974, and he described an external approach via the thyroid cartilage and the placement of a silastic subperichondrial implant to mobilize the vocal fold (thyroplasty type 1).

This procedure is indicated when vocal cord paralysis or atrophy is the etiology of aspiration secondary to inadequate glottic closure.

Contraindications may include poor pulmonary reserve (ie, chronic obstructive pulmonary disease [COPD]).

The patient is placed in the supine position with the neck extended and is prepared and draped in the usual sterile fashion. During the procedure, the patient is under monitored sedation with local anesthesia. The incision is placed at the level of the thyroid cartilage. The incision is carried through the subcutaneous tissue, and the strap muscles are divided in the midline to the level of the thyroid cartilage.

The anterior lateral surface of the thyroid cartilage is skeletonized on the paralyzed side to the level of the perichondrium, and the height of the cartilage at the notch is measured anteriorly with calipers. Next, the middle is marked, and the lateral portion is elevated at the middle third of the affected side with a perichondrial elevator.

Windows are based 5-6 mm from the middle mark, which approximates the anterior commissure of the glottis. Males require a window of 6 X 12 mm, and females require a window of 4 X 9 mm (Stasney, 1996). The cartilage is marked through the perichondrium (with either a Bovie needle tip or methylene blue at the 4 corners), and a posterior-based flap of perichondrium is raised. The cartilage is then incised with a No. 11 blade (or, if calcified, drilled with a diamond burr) to approximately half the width of the cartilage. The rest is elevated using a Penfield elevator to the inner perichondrium.

The inner perichondrium is not transgressed but is elevated on the inner surface if the window is removed. Alternatively, the perichondrial window may be left in place, thus requiring a smaller silastic implant (Myers, 1997). The patient's voice is checked at various levels of medialization to determine the size of the implant by depressing the window into the larynx. The silastic implant is formed and tested, with reshaping as needed until the desired result is achieved.

A fiberoptic laryngoscopy is performed to determine closure of the glottic defect. The implant may be sutured in place with permanent sutures or created with a "lip" to prevent migration. The perichondrium is closed with 5-0 absorbable sutures, and a layered closure of the neck wound is performed (Stasney, 1996; Koufman, 1997).

Endoscopic approaches that involve injection of varying substances to stiffen and/or medialize the vocal fold have been described. Teflon injection was once common but now is rarely performed because of the development of Teflon granulomas, extrusion, and migration. Glycerin, collagen, and Gelfoam injections are performed but only have a temporary effect. These injections are commonly used for vocal folds in which function may be expected to return and/or as a prethyroplasty medialization procedure.

Indications include glottic insufficiency and aspiration with unilateral vocal fold paralysis.

Contraindications to this procedure are cancer of the larynx and bilateral vocal fold paralysis.

Complications include bleeding, infection, airway obstruction, exercise intolerance, dysphonia (Beaty, 1999), and granuloma formation.

The patient must remain hospitalized for 24 hours following surgery for airway observation. Antibiotics are administered postoperatively for 3 doses.

Laryngeal closures

Habal and Murray described the creation of an epiglottic flap for laryngeal closure in 1972, and, in 1983, they described a supraglottic closure with an epiglottic flap. In 1975, Montgomery described a glottic closure technique that entails a midline thyrotomy with suturing of the true vocal cords, ventricles, and posterior commissure.

Since that time, both endoscopic and external approaches have been described to perform either epiglottic or glottic closure procedures.

The epiglottis can be sutured over the glottis, and/or the vocal cords can be closed with sutures. These procedures require an alternate route of respiration, and a tracheotomy is required. These procedures are reversible, and they should be used in the setting of a reasonable expectation of return of functional laryngeal protection by the vocal folds.

Contraindications to this procedure are chronic aspiration with a poor recovery prognosis.

During the procedure, a lateral pharyngotomy approach is undertaken, and the epiglottis is sutured to the aryepiglottic folds and arytenoids. Careful denuding of these areas at the points of contact is undertaken prior to suturing. The base of the epiglottis may be scored to lessen its elasticity.

Although dehiscence of the flap may ensue, botulinum toxin injection is reportedly a useful adjunct to limit vocal fold movement in prevention of this complication (Pototschnig, 1996).

Following surgery, patients should receive tracheotomy care; postoperative antibiotics; wound care; and, when appropriate, drain removal. Patients should be monitored for dehiscence with recurrent aspiration.

Contraindications to this procedure are chronic aspiration with a poor chance of recovery.

During the procedure, a midline thyrotomy is performed, and the true cords, ventricles, and arytenoids are denuded of epithelium. The larynx is closed with sutures, passing through the thyroid cartilage, the anterior commissure ipsilaterally to the contralateral side through the vocal cord, and the arytenoid cartilage. Sutures then pass back through the posterior portion of the ipsilateral cord and the thyroid cartilage. The other side is similarly addressed, and the thyrotomy is closed in a standard fashion (Montgomery, 1975).

Complications include an inability to reverse secondary to severe glottic scarring (see Tracheotomy).

Patients should receive adequate care following surgery, including tracheotomy care, postoperative antibiotics, and wound care.

Tracheoesophageal diversion

This procedure is indicated for patients with severe, life-threatening, chronic aspiration who have a potential for recovery from the disease process that causes aspiration.

Contraindications to tracheoesophageal diversion include upper tracheal pathology.

The patient is prepared and draped in a similar fashion to that of a tracheotomy (see Tracheotomy). The approach to the neck is via a horizontally placed skin incision. The incision is carried out in the natural skin creases at the second or third tracheal ring, and the incision is carried through the platysma.

Subplatysmal flaps are developed superiorly and inferiorly. The strap muscles are divided in the midline, and the thyroid isthmus is ligated and separated in the midline, exposing the cervical trachea. The trachea is divided between the third and fourth rings (if a previous tracheotomy is in place, the incision is performed at the level of the tracheostomy) and is mobilized from the esophagus 1-2 cm superiorly and inferiorly. The proximal trachea is then anastomosed to the esophagus anteriorly, and the distal stump is brought to the neck as a tracheostomy stoma and sutured in place to the skin. The cervical wound is closed in a standard layered fashion.

Complications inherent to this procedure are recurrent laryngeal nerve injury, tracheoesophageal fistula, and carotid artery injury and infection (including potential mediastinitis).

Postoperative care includes tracheotomy care, a nasogastric tube for enteral feeding (several postoperative days), wound care, and drain removal. Sutures are removed in 7-10 days.

Laryngotracheal separation

Contraindications to this procedure mirror those for tracheoesophageal diversion.

Several modifications of the original procedure developed by Lindeman have been described. Lindeman's modification included creating a blind pouch with the proximal trachea instead of creating an anastomosis with the esophagus (Yarington, 1976). Diversion of the proximal trachea into the esophagus (as in the Lindeman procedure) is difficult when a preexisting tracheostomy is present because of the need for a long segment of proximal trachea for the anastomosis. Therefore, LTS is preferred when a tracheotomy is already present. The proximal stump is oversewn and is then reinforced with the sternothyroid muscle.

The resulting proximal pouch has not been associated with food stasis or regurgitation, although Snyderman et al reported an increased risk of fistula formation at the proximal stump (1994). Tucker advocated nonclosure of the proximal tracheal stump in favor of creating a second stoma through the SCM muscle (1979). This technique was performed to decrease external drainage.

These procedures are potentially reversible, although success is variable. Dedo stated that he no longer performs these operations because of the inability to reverse them (1990); whereas, Snyderman et al reported successful reversals in select patients (1988).

Adjunctive procedures

Cricopharyngeal myotomy is performed for achalasia secondary to sustained contraction of the cricopharyngeus muscle during swallowing. This is usually secondary to neurologic disorders but may be used in swallowing dysfunction after resection of supraglottic, oral, and oropharyngeal carcinoma.

Indications include cricopharyngeus achalasia in conjunction with Zenker diverticulum and oculopharyngeal muscular dystrophy.

Contraindications are as a primary procedure for aspiration, lack of elevated manometric pressures, and life-threatening aspiration.

During the procedure, the patient is positioned, with the neck prepared and draped in the usual sterile fashion. Once the patient reaches an appropriate depth of surgical general endotracheal anesthesia, an esophageal bougie or cuffed endotracheal tube is passed into the cervical esophagus. Then, via a lateral cervical approach to the skin, subcutaneous tissue and platysma are incised along the anterior border of the SCM muscle.

The trachea and the carotid sheath are identified and retracted medially and laterally, respectively. The pharynx is mobilized to reveal the posterior cricopharyngeus muscle. The muscle is incised over the previously inserted tube (if an endotracheal tube was inserted, the cuff is inflated) down to the esophageal mucosa. The neck is closed in the standard fashion with a drain.

Complications to this procedure include salivary fistula, wound infections, recurrent laryngeal nerve injuries, and vocal cord paralysis.

Postoperative care includes wound drain observation for increasing drainage once feeding begins, wound care, and antibiotics.

Patients who experience chronic aspiration but who have functional alimentary canals may benefit from a feeding gastrostomy or jejunostomy. They may be performed either as an open procedure or as an endoscopic procedure. These procedures allow for bypass of the upper aerodigestive system and prevent aspiration through avoidance of swallowing. They do not prevent reflux, and positioning during and after feeding is important to prevent aspiration of refluxate.

Aspiration is well documented in the presence of feeding enteral tubes and accounts for a significant degree of morbidity and mortality. In 1992, Jarnigan et al reported 15% aspiration pneumonia and 50% mortality in patients who had undergone percutaneous gastrostomy placement (PEG). In 2000, Klodell et al reported a rate of 4% aspiration pneumonia in traumatically brain-injured patients undergoing PEG feedings. Alimentary bypass procedures are frequently the first interventions in chronic aspiration secondary to swallow dysfunction.

This procedure is indicated in patients with dysphagia, chronic aspiration, and/or malnutrition with functioning gut. Jejunostomy tubes may be placed via the gastrostomy into the jejunum in cases of gastroparesis.

Contraindications include infections of the abdominal wall, nonfunctional gut, bleeding diathesis, unstable neck/cervical spine, intestinal perforation, and unstable cardiac or pulmonary conditions. Percutaneous endoscopic gastrostomy is contraindicated in patients who are unable to cooperate during the procedure.

For surgery, the patient is brought to the endoscopy suite and is placed under conscious sedation. Short-acting benzodiazepines and opioid analgesics are frequently used. The patient's vital signs and oxygen saturation are monitored. An oral airway large enough for the flexible esophagoscope is inserted in the mouth. The tip of the endoscope is passed to the level of the cricopharyngeus muscle with active swallowing by the patient. The endoscope is then passed to the stomach.

The abdomen is prepared and draped in a sterile fashion. The abdominal operator can see the endoscopic light shining through the abdominal wall. A left upper quadrant abdominal puncture is performed with a Seldinger-type needle. A wire is passed via the needle into the abdomen and is grasped with a snare by the endoscopist. This wire is brought out via the mouth, and a feeding tube is advanced over it.

The feeding tube is fastened via interior and exterior flanges that hold the tube in place. Feedings may begin on the first postoperative day (Kimmey, 1994).

Complications include infection of the stoma, bleeding, peritonitis, esophageal perforation, and obstruction of the tube.

Patients should receive postoperative antibiotics and wound care. The caregiver should be provided with instructions on flushing and maintaining patency of the tube.

Control of salivary output

Aspiration of salivary secretions can be a source of aspirated materials. Control of salivary output can be accomplished via the following surgical procedures: excision of salivary glands, ductal ligation, ductal re-routing, parasympathetic nerve resection, and more recently, reduction of salivary flow has been obtained successfully by injection to the submandibular and parotid glands with botulinum toxin (Ellies, 2004).

Ductal re-routing is commonly used for anterior drooling. Increased posterior secretions in a patient who is aspirating may actually worsen both the severity and the frequency of aspiration. Salivary glands produce 1500 mL of saliva per day (Lee, 1999). Bilateral 4-duct ligation or bilateral submandibular gland excision and parotid duct ligation eliminates most oropharyngeal secretions that lead to aspiration. Four-duct ligation is advocated as an easier and shorter procedure with equal effectiveness. Excision of the submandibular glands is advocated to minimize the possibility of increased risk of abscess formation in retained submandibular glands.

This procedure is indicated in patients with chronic aspiration secondary to ptyalism, most commonly associated with cerebral palsy, epilepsy, and Down syndrome.

For surgery, the patient is placed on the operating table in the supine position, and the head is turned to the opposite side. The incision line is marked 3 cm below the mandibular margin in the submandibular area. The notch of the facial artery is marked. Paralytic agents are not administered to the patient because they prevent identification of the marginal mandibular nerve with a nerve stimulator.

An incision is made following a natural skin crease (if possible) and is carried through skin and subcutaneous tissue to the level of the platysma muscle. The platysma muscle is carefully incised as the marginal mandibular nerve passes deep to the platysma in the fascial covering. The marginal mandibular nerve is identified with the nerve stimulator and preserved. The posterior facial vein is clamped and ligated. The anterior facial artery and vein are identified, clamped, and ligated.

The fascia that covers the gland and attaches it to the mandible is dissected in a blunt fashion. The dissection is then carried medial to the posterior facial vein and anterior to the anterior belly of the digastric muscle. The mylohyoid muscle is identified, and the attachments to the submandibular gland are dissected away from the gland. The free edge of the mylohyoid is retracted, and the lingual nerve is identified. Dissection using a blunt dissector below the lingual nerve identifies the hypoglossal nerve and the Wharton duct. The parasympathetic ganglion is identified along the lingual nerve, and fibers to the gland are divided. The duct is divided and ligated. All further attachments are released from the gland. The common facial vein and the facial artery are clamped and ligated. The gland is removed, and the neck wound is closed in layers, as previously described (Olsen, 1996).

Parotid duct ligation is then undertaken. The opening of the parotid duct is identified opposite the maxillary second molar. An incision is made, and the duct is isolated. The duct is then clamped, cauterized, and ligated. The wound is not closed (Dundas, 1979).

Ensuing complications include marginal mandibular nerve injuries with resultant lower lip paralysis, wound infection, lingual and hypoglossal nerve injuries, and salivary fistulas. Chronic parotitis and/or submandibular sialadenitis may occur with duct ligation procedures.

Postoperative care includes wound care and antibiotics. Drains are removed once drainage is minimal. Sutures are also removed.

Local injection of botulinum toxin type A acts at the cholinergic receptors within the salivary glands to reduce the salivary secretions. The effect is temporary, usually lasting approximately 12 weeks. The procedure is usually done with ultrasound guidance to ensure that the injection is into the substance of the glands. The amount injected is approximately 20 units to each parotid gland (divided into 3 locations in the gland) and 10-20 units into each submandibular gland (divided into 2 locations in each gland). Potential complications include extravasation outside the gland tissue leading to facial paresis, airway, or swallowing dysfunction. The incidence is low and complications, like the beneficial aspects of this treatment, are transient (Ellies, 2004).

Gastric reflux that has not responded to medical management and that is associated with aspiration pneumonia may benefit from fundoplication. In this procedure, a portion of the stomach is wrapped around the lower esophagus to recreate a sphincteric mechanism, thus preventing reflux. Endoscopic and open abdominal approaches are reported in the literature. Nissen described a 360° wrap (Grosfeld, 1991).

Indications include failure to thrive, refractory reflux, emesis, aspiration pneumonitis/pneumonitis, esophageal stricture, and Barrett esophagus/esophagitis despite conservative/medical therapy.

Contraindications to this procedure are an inadequate trial of medical therapy and aspiration secondary to causes other than reflux (eg, glottic incompetence, neurologic swallowing dysfunction).

During the procedure, the patient is placed in a supine position, and the abdomen is prepared and draped in a sterile fashion. A standard incision is performed, and the incision is carried through the skin, subcutaneous tissue, muscle layers, and peritoneum. The gastric fundus is identified. The vagus nerves are identified and preserved.

The gastric wrap is performed with 3 cm of the fundus encircling the intra-abdominal portion of the esophagus. Proper placement of heavy silk sutures to the seromuscular layers of the stomach, the anterior esophageal wall smooth muscle layer, and the fundus is critical to this procedure. The short gastric vessels must be identified; they can be a significant source of bleeding. These vessels may be ligated as needed to achieve a tensionless wrap. Once the wrap is in place, the wound is closed in a layered fashion (Dundas, 1979).

Complications inherent to this procedure include early satiety, esophageal obstruction, small bowel obstruction, wound infection, dehiscence, pancreatitis, inadvertent splenectomy, inability to belch, wound breakdown, and failure to control gastroesophageal reflux.

Postoperative care includes wound care and antibiotics. A nasogastric tube is used for drainage. When patients resume a solid diet, small, well-chewed food boluses are recommended.

Preoperative details

Intraoperative details

Postoperative details

Follow-up

Complications to surgical intervention for chronic aspiration are procedure specific and are outlined with each procedure.

Outcome and prognosis to surgical intervention for chronic aspiration are procedure specific and are included with each procedure.

Surgical Management of Chronic Aspiration

AUTHOR AND EDITOR INFORMATION

INTRODUCTION

History of the Procedure

Problem

Etiology

Pathophysiology

Clinical

INDICATIONS

RELEVANT ANATOMY

CONTRAINDICATIONS

WORKUP

Imaging Studies

Diagnostic Procedures

TREATMENT

Medical therapy

Surgical therapy

Tracheotomy

Laryngectomy

Laryngeal suspension

Total and partial cricoid resection

Vocal fold medialization

Laryngeal closures

Tracheoesophageal diversion

Laryngotracheal separation

Adjunctive procedures

Control of salivary output

Preoperative details

Intraoperative details

Postoperative details

Follow-up

COMPLICATIONS

OUTCOME AND PROGNOSIS

MULTIMEDIA

REFERENCES