SNARE UVULECTOMY FOR UPPER AIRWAY RESISTANCE SYNDROME

JAMES NEWMAN, MD, FACS

Excessive soft tissue of the palate is found in patients with upper airway resistance syndrome. One method of treating the palate is with a uvu|ectomy using a hot snare. The modern technique of snare uvulectomy is described in detail.

The upper airway resistance syndrome (UARS) defines a group of patients with clinical signs and symptoms of excessive daytime somnolence in the absence of obstruc- tive sleep apnea. Often times these patients complain of snoring. These patients have increased upper airway re- sistance that is characterized by partial collapse of the airway resulting in an increased resistance to airflow. Physical findings often include excessive palatal tissue and narrowing of the oropharynx and hypopharynx. The in- creased respiratory effort required results in multiple sleep fragmentations as measured by very short alpha electroencephalogram (EEG) arousals. 1 Snoring may or may not be a feature of UARS. The resistance to airflow is typically subtle and does not result in apneic or hypopneic events; therefore, a normal respiratory index is recorded. However, it does result in an increasingly negative in- trathoracic pressure during inspiration, which can be mea- sured using an esophageal manometer as an adjunct to a polysomnogram. Therefore, diagnosis of UARS rests on symptoms of excessive daytime somnolence coupled with polysomnographic documentation of >10 EEG arousals per hour of sleep. These EEG arousals are correlated with episodes of reduced intrathoracic pressure, as noted on esophageal manometry. The esophageal pressure monitor- ing is an indirect measurement of upper airway collapse. When the esophageal pressure readings exceed -10 cm of water, the work of breathing is increased, and polysom- nogram with EEG monitoring will pick up these alpha arousals, 2 The frequency of alpha arousals during sleep is thought to be the major contributing factor to daytime somnolence.

The sites of airway obstruction are similar to frank obstructive sleep apnea syndrome, but the degree of col- lapse or relaxation of muscle tone in the palate and or tongue is lower. In the past, these patients have been successfully treated with palate procedures designed to reduce soft tissue mass and stiffen the palate. 2 The current focus has been on minimally invasive surgery to treat UARS, and has included laser-assisted uvulopalatoplasty, bovie uvulectomy, and, injection snoreplasty. The purpose

From the Division of Otolaryngology/Head and Neck Surgery, Stanford University Medical Center, Stanford, CA.

Address reprint requests to James Newman, MD, 50 S. San Mateo Drive, Suite 320, San Marco, CA 94401-3861. E-maih newman_md@ hotmail.com.

Copyright 2002, Elsevier Science (USA). All rights reserved. 1043-1810/02/1302-0016535.00/0 doi:l 0.1053/otot.2002.127285

of this chapter will be to describe the current technique of palatal volume reduction through the means of uvulec- tomy with a hot snare. It should be noted that the proce- dure itself is not a new one; indeed it dates back to Greek physicians in the Byzantine era. 3 The modern form of the procedure is performed strictly in a clinical setting with local anesthesia. In cases where uvulectomy does not im- prove the UARS, procedures related to the tongue base or medical treatment with continuous positive airway pres- sure (CPAP) are alternatives.

MATERIALS

Equipment needed includes a headlight, tongue depres- sor, bayonet forceps with Brown-Adson tissue grasping tips, and a standard cautery source for attachment to a standard hand controlled snare. Several manufaturers supply cautery snares for otolaryngology, including Karl Storz Instruments (Culver City, CA) and Ellman Interna- tional Inc (Hewlitt, NY) (Fig 1).

The anesthetic technique is similar to that of preparation for laser uvulopalatoplasty. The oropharynx is sprayed with 20% benzocaine (Hurricaine Spray; Beutlich, Wauke- gan, IL) followed by injection with 1.5 cc of equal mixture of 1% Lidocaine with 1:100,000 epinephrine (Abott, Chi- cago, IL) and 0.25% bupivicaine through a one and a quarter inch 27 gauge needle attached to a 3 cc syringe (Figs 2 and 3).

When performing injections and using instruments in the oropharynx the patient is instructed to open their mouth and to breathe in and out through their mouth only. This action relaxes the genioglossus muscle and al- lows unimpeded view of the uvula and palate. In cases of larger tongues, an assistant may need to depress the tongue with a standard sweetheart tongue depressor.

During the preoperative examination, the patient is asked to elevate the palate for general muscle tone and the palate is palpated to assess for any submucous cleft of the hard palate. The thickness of the palate and uvula base is also assessed to help determine the duration of cauteriza- tion and speed of snare tightening. The snare is always tested prior to introduction and then relaxed so that the initial diameter of the loop opening is the size of a quarter. A "dry run" placement of the snare is performed so the operator can anticipate movements of the palate and to determine the position of the uvula amputation. Some- times a cautery mark is scored with the tip of the snare to mark the level of amputation and to confirm adequate anesthesia.

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FIGURE 1, Standard cautery snare with three-finger hand con- trol.

T E C H N I Q U E

After pretreatment preparations are checked--as well as ensuring proper grounding--an assistant stands to the left of the patient with a hand held suction and tongue de- pressor. The patient is given a 500 cc emesis basin to hold. The physician should be wearing a headlight and have the Brown-Adson bayonet forcep in left hand and the control snare in right hand; once this is done, he is ready to begin the procedure. With the mouth open, the procedure is initiated by engaging the uvula and snugging the snare at the indicated level for amputation (Figs 4 and 5). The cautery setting depends on the source to be used. In my experience, three different cautery sources have been uti- lized with equally satisfactory results in hemostasis: the Cameron Miller radiofrequency source is typically set be- tween 3 and 4; the Ellman radiotron box is set on 4 to 5 with a partially rectified current; and the Valley Lab Force 2 electrosurgical generator is set in the cut mode with a

FIGURE 2. Application of topical anesthesia into the oral cavity and oropharynx.

FIGURE & Injection of local anesthetic at the neck of the uvula. Injection is within the muscle layer.

blend of 2 and power setting of 3. Regardless of the generator used, one should be familiar with their current device and practice the procedure on a template from an uncooked piece of chicken breast.

The procedure is then begun with depression of the footswitch and closing of the snare loop. During the pro- cedure, there is an absence of smoke plume because no tissue is being vaporized as in either laser or free hand cautery techniques. This is an important fact, and it is also why there is no visual obstruction by an assistant's hand or suction tip device trying to evacuate a plume. The procedure culminates in the forceful closure of the snare, resulting in amputation of the uvula which is then re- moved from the mouth with the bayonet forceps (Fig 6). After the specimen is removed, the stump is observed for any potential sites of bleeding (Fig 7). If any red spots are seen, they can be point cauterized with the partially drawn closed free snare which makes the end into a narrow wire cautery tip.

D I S C U S S I O N

The patients are usually impressed with the brief nature of the procedure and lack of discomfort. Patients are ob- served for 15 minutes and then allowed to go home with a prescription for 3 days of penicillin and a week's supply of liquid codeine with acetaminophen or liquid hydro- codone with acetaminophen. Patients are instructed to

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mance of the procedure requires an appreciation of the anatomy and a feel for the amount of manual squeeze over the course of the procedure. The main risks of other uvu- lectomy procedures have included bleeding and excessive scarring, sometimes resulting in stenosis of the orophar- ynx inlet. Compared to the laser, there is less chance of past pointing or posterior wall injury. Compared to free hand bovie tip cautery amputation, there is less chance of collateral heat damage and less smoke, and a more stable target is present as the single instrument both grasps and cuts.

The lack of smoke plume makes for better visualization when compared to other techniques and the limited lateral thermal damage to the palate makes for faster recovery and diminshed discomfort when compared to laser uvu- lectomy or laser palatoplasty.

Choosing the location of amputation is the most variable portion of the procedure, because a low, mid, or high amputation can be performed. A low amputation is de- fined as a site of tissue cut inferior to the midway length of the uvula, and the mid amputation is defined as the site of tissue cut exactly at the midline length of the uvula. A high amputation is defined as a site of tissue cut above the midway length of the uvula. The length of the uvula is observed beginning at the muscular base and extending to the free tip of the uvula. Treatments for simple snoring can also be performed in similar locations. More risk of bleed- ing has been reported when high amputations are per- formed, possibly because of the larger size diameter ves- sels, which includes arterioles, in this location.

FIGURE 4" Depressing the tongue and securing the snare around the uvula,

return to the office in 3 weeks. If there is bleeding or increased pain after the first 3 days, they are encouraged to come in for an office visit prior to their routine 3 week visit. Their return visit at 3 weeks usually shows a well- healed mucosa and normal palate contraction. There have been no cases of bleeding with the first 30 trials performed to date. Patients have reported pain lasting between 3 and 20 days. No cases of stenosis, voice disturbance, infection, or excessive scarring have been noted. Most patients re- port that their symptoms of excessive daytime somnolence and snoring have been eliminated or significantly re- duced. We have been unsuccessful in our attempts to universally obtain post treatment polysomnograms with esophageal monitoring to confirm the abatement of signs associated with UARS. It is important to stress that some sort of clinical follow up or testing is recommended during the following 2 years to check for continued success. In cases where the symptoms of excessive daytime somno- lence has not improved, CPAP or surgery to address tongue base collapse should be discussed.

This particular procedure seems to offer several advan- tages when compared to similar treatments for UARS or even snoring. It is a single procedure with minimal risks and does not require the expenditure of a unique piece of equipment for the sole purpose of snare uvulectomy. The anatomic configuration of the uvula makes it an ideal candidate for amputation with a snare. The ability to produce circumferential cauterization and cutting makes for excellent hemostasis as well as limiting lateral collat- eral thermal damage. Loop tip cauteries have limited col- lateral damage when used in pure cutting modes. Perfor-

FIGURE 5: Snare is tightened around the base of the uvula and heat cauterization is initiated.

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Possible complicat ions include vasovaga l responses f rom pat ients dur ing local anesthetic adminis t ra t ion, bleeding, and excessive scarring; they have all been re- por ted wi th this procedure . 4 Excessive pain, infection, and dysphag ia are also possibilities, bu t they have not been reported. A rare compla in t f rom one pat ient involved the inability to collect and hur l a w a d of spit fol lowing his uvulec tomy. The author is not aware of any other compli- cations associated wi th this p rocedure and continues to offer it for cases of UARS and s imple snoring.

FIGURE 6. Grasping of the uvula from the oral cavity after its transection by closing the snare across the base of the uvula.

FIGURE 7. Open wound at the base of the uvula at completion of the procedure.

REFERENCES 1. Guilleminault C, Stoohs R: The upper airway resistance syndrome.

Sleep Res 20:250, 1991 2. Newman JP, Moore M, Utley D, et at: Recognition and surgical man-

agement of the upper airway resistance syndrome. Laryngoscope 106:1089-1093, 1996

3. Lascaratos J, Assimakopoulos D: Surgery on the larynx and pharynx and Byzantium (AD 324-1453): Early scientific descriptions of these operations. Otolaryngol Head Neck Surg 122:579-583, 2000

4. Coleman J, Rathfoot C: Oropharyngeal surgery in tire management of upper airway obstruction during sleep. Otolaryngol Clin North Am 32:263-276, 1999

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