1 INTRODUCTION

The clinical significance of adenoid hypertrophy was not truly appreciated until the mid-19th century. This was due to their relatively inaccessible location given the technology available at that time. Once discovered, various techniques for the removal of the adenoids were developed. Some of these basic techniques have remained with us since that time.

Although commonly known for causing chronic sinonasal symptoms or influencing chronic ear disease, enlargement of the adenoids can play a prominent role in obstructive sleep apnea.

2 PATIENT SELECTION

Children with signs and symptoms of obstructive sleep apnea, or those with polysomnogram-proven disease, should have their adenoids evaluated as part of a routine work-up. This can be done in a number of ways. In children of just about any age, flexible fiberoptic nasopharyngoscopy provides the most direct means of evaluation. A camera and monitor attached to the scope can provide families with visual reinforcement. Alternatively, a lateral plain film of the nasopharynx can demonstrate adenoid hypertrophy and resultant compromise of the nasal air column. Although not routinely obtained to evaluate for adenoid hypertrophy, CT scans and MRIs can also demonstrate enlargement of the adenoid pad.

Adenoidectomy is usually inappropriate in children with a history of cleft palate, overt or submucous, or those with a history of velopharyngeal insufficiency. A balance between relief of obstruction and the creation of velar incompetence is crucial. Families must be counseled as to the increased risk for this important complication, even if a limited procedure is performed.

Very commonly, adenoidectomy is performed in concert with tonsillectomy as the most common surgical procedure to treat obstructive sleep apnea in children.

3 OUTLINE OF PROCEDURES

Various options for airway management exist and it is important for the surgical and anesthesia teams to decide on this before the procedure begins. A straight endotracheal tube, laryngeal mask airway (LMA) or oral RAE tube (Ring–Adair–Elwyn) may be used. The surgeon must consider factors such as other procedures (i.e. tonsillectomy) being performed when deciding on the type of airway management.

Historically, adenoidectomy was performed with the surgeon facing the patient, who was sitting upright. Some surgeons still currently employ an orientation similar to that of endoscopic sinus surgery. Today, the Rose position is commonly used in which the patient’s head and neck are extended and the surgeon sits behind the patient. The eyes are protected and the patient is sterilely draped. A mouth gag, such as the Crowe–Davis or McGyver, is then carefully inserted into the mouth and the oropharynx is exposed. The mouth gag can be suspended per surgeon preference. The soft palate should then be visually inspected and palpated to ensure that a submucous cleft is not present. Visualization of the nasopharynx can be easily achieved using a defogged #5 laryngeal mirror and a headlight. Exposure can be enhanced using either one or two red rubber catheters. These are placed transnasally, retrieved from the oropharynx and then clamped back on themselves, effectively retracting the soft palate.

3.1 CURETTE ADENOIDECTOMY

The use of a curette to remove the adenoids dates back to some of the earliest attempts at this procedure and remains an incredibly popular technique worldwide. The original design of Jacob Gottenstein has been modified and many different lengths, widths and curvatures are available. The basic principle is that of a sharp horizontal knife-edge that is designed to cut through the base of the adenoid bed. The instrument is designed to follow the natural curvature of the nasopharyngeal skull base (Fig. 66.1).

Fig. 66.1 Placement of adenoid curette. Note how curve of instrument approximates contour of skull base for effective removal of tissue without damage to underlying structures.

The curette may be passed blindly into the nasopharynx, or the laryngeal mirrors may be used to guide the cutting edge into position. Visualization of the fossa of Rosenmuller helps guide appropriate curette size. The curette is placed against the vomer and then pushed through the adenoid tissue to the more resistant deeper layers. The handle is pulled toward the head and the surgeon’s other hand acts as a fulcrum at approximately the level of the incisors. The curette is swept in an arc through the adenoid tissue until the level of Passavant’s ridge, which is the inferior aspect of the dissection. After the initial pass, the adenoid bed is inspected for the completeness of the procedure. If there is residual adenoid tissue left behind, it must be removed using either a smaller curette or St Claire-Thompson forceps. A tonsil sponge is then generally placed into the nasopharynx to aid in hemostasis. These sponges may contain medications such as oxymetazoline or can be used alone. It is our preference to finalize hemostasis using a suction monopolar cautery using mirror guidance although other techniques including pressure packing, bismuth subgallate and silver nitrate have been described. Once final hemostasis is achieved, the nasopharynx and oropharynx should be irrigated and the stomach emptied of its contents prior to extubation.

3.2 ABLATION ADENOIDECTOMY

The widespread use of the suction monopolar cautery unit to achieve hemostasis after adenoidectomy naturally led to its use as a primary means of reducing adenoid tissue. With the patient in the Rose position, as described above, the adenoid pad is viewed with a mirror. The monopolar cautery unit, generally set at 30–40 watts, can then be shaped to fit the patient’s unique anatomy. Starting at the choana and working inferiorly, the adenoids are sequentially ablated using the cautery unit (Fig. 66.2). As the tissue fluid is vaporized there is dramatic reduction in the size of the adenoid tissue. Care is taken to avoid inadvertent cautery of non-adenoidal tissue. Bleeding tends to be minimal using this technique and can be controlled with any of the methods described above.

Fig. 66.2 Ablation adenoidectomy. Under mirror visualization the adenoid pad is ablated using the suction monopolar cautery. Note ability to adequately view the choana and Eustachian tube region with this technique to avoid inadvertent injury to these structures.

Proponents of this technique cite its low technical difficulty, lower intraoperative blood losses, reduced operating room times and reduced cost compared to other techniques as rationale for its widespread use.

3.3 TRANSNASAL ADENOIDECTOMY

Essentially, two types of transnasal procedures exist. Both utilize rigid nasal endoscopes as in endoscopic sinus surgery. In traditional transnasal techniques the adenoids are removed using sinus instruments such as Blakesley forceps. More recently the soft tissue shaver has been advocated to allow more rapid removal of the adenoid tissue.

These techniques are particularly useful for adenoid tissue that prolapses into the nasal cavity or for residual adenoidal tissue in the choana that cannot be removed via a transoral route. Another potential indication for this technique would be in the child with cervical instability who cannot have the neck extended, such as in certain cases of Down syndrome. Still others have advocated this technique for use in children with submucous cleft palate, where only limited amounts of tissue are to be removed.

During a powered transnasal adenoidectomy, the child is maintained in neutral position and the nasal cavities are decongested. Our preference is to use topical 0.05% oxymetazoline on neurosurgical pledgets. Once the nasal cavity is decongested, a 0º telescope is introduced and used to visualize the adenoids. Anatomic factors can limit ­visualization such as a markedly deviated nasal septum or hypertrophy of the inferior turbinate. The microdebrider can then be introduced into either the ipsilateral or contralateral nostril and the adenoids can be removed. Bleeding can be controlled using bipolar or monopolar cautery passed transnasally or using techniques described above.

3.4 POWERED TRANSORAL ADENOIDECTOMY

Practiced in the United States for well over a decade now, the transoral use of a microdebrider has gained widespread popularity because of its ease of use, safety and proven efficacy. One criticism of this technique is the slightly higher cost associated with the microdebrider blades. It is our procedure of choice for removal of the adenoids.

With the patient in the Rose position with transnasal catheters and a mouth gag in place, the mirror is used to visualize the nasopharynx. Various pre-curved blades exist on the market and these allow for continued visualization during removal (Fig. 66.3). Starting in the region of the choana, the adenoid tissue is removed in a side-to-side manner that progresses inferiorly. The microdebrider is generally set on oscillating mode at 1500 rpm and tissue is removed only at the location of the blade, which is kept under vision at all times. This allows for precise control during removal of tissue. By angling the blade, the Eustachian tube orifice can be cleared of any adenoid tissue without injury. Furthermore, the depth of dissection can be more effectively monitored compared to the curette technique to avoid inadvertent injury to the underlying musculature. This technique also allows the surgeon to very precisely leave adenoid tissue inferiorly to minimize the risk of postoperative velopharyngeal insufficiency, especially in the child with a developmental anomaly of the palate.

Fig. 66.3 Powered transoral adenoidectomy. Note excellent visualization afforded by this procedure. Precise control of the tip of the microdebrider is possible to optimize adenoid removal and minimize risk of injury to surrounding structures.

Once the adenoids are removed bleeding is controlled as described above.

3.5 RADIOFREQUENCY ADENOIDECTOMY

This technology, which has been in use for tonsillectomy, uses radiofrequency energy to excite the sodium ions in saline, which creates a plasma that disintegrates tissue bonds at temperatures around 80º. The result is similar to cautery adenoidectomy but without the tissue char from 400º temperatures of the cautery. A suction wand that bends easily into the nasopharynx but does not clog during resection remains a challenge.

3.6 POSTOPERATIVE MANAGEMENT AND COMPLICATIONS

Upon arrival in the recovery room, patients should be adequately monitored with continuous pulse oximetry. Once the child is fully awake, oral diet may be resumed. Initially this is in the form of clear liquids and diet may then be advanced to soft foods. Adenoidectomy performed without concurrent tonsillectomy generally has a quicker recovery time with much less postoperative pain. The use of narcotics is generally not necessary and should probably be avoided in the child with sleep apnea. Following adenoidectomy, we favor the use of non-steroidal anti-inflammatory drugs, such as ibuprofen, alternating every 3 hours with acetaminophen. The best literature available suggests that this regimen is more effective for control of pain, and does not pose an increased risk of bleeding.

Adenoidectomy performed alone is generally an outpatient procedure and most patients are able to go home the day of surgery. Temporary observation can be considered in patients with craniofacial abnormalities, obesity, bleeding disorders, significant obstructive sleep apnea or other medical co-morbidities.

Fortunately, complications after adenoidectomy are rare. The most common complication of adenoid surgery is regrowth of tissue causing recurrence of symptoms. A recent large series by Stewart and colleagues found a 1.6% rate of secondary adenoidectomy. Postoperative hemorrhage is rare and is usually associated with concurrent tonsillectomy. Torticollis is known to occur after adenoidectomy from irritation of the paravertebral muscles. A more severe form of a post-adenoidectomy inflammatory process in the upper cervical region is Grisel syndrome, a non-traumatic atlantoaxial subluxation. It has been postulated that the risk of Grisel syndrome increases with increasing use of monopolar cautery in the nasopharynx.

The problem most otolaryngologists fear following adenoidectomy is velopharyngeal incompetence (VPI); in most cases it is temporary and resolves in 4–6 weeks. However, there is a small percentage of children, reported to range from one per 1500 to one per 10,000 patients, who will have persistence of the VPI. While the adenoid pad is not part of the velopharyngeal sphincter, it may assist in closure in children with structural or functional abnormalities of the soft palate. Children at risk of developing persistent VPI after adenoidectomy often can be identified preoperatively by presence of repaired cleft palate, submucous cleft palate, high arched palate, or palatal hypotonia. When it is necessary to open up the nasopharyngeal airway for these children, performing a very high, perichoanal adenoidectomy can be safely done with a variety of techniques all of which demand close visualization of the site of resection.

Perhaps the worst complication is nasopharyngeal stenosis. Depending on the severity, surgical correction is difficult and unpredictable with a high rate of failure. A cluster of cases in Texas following use of the potassium titanyl phosphate (KTP) laser for adenoidectomy highlighted this otherwise rare complication.

4 SUCCESS RATE OF PROCEDURE AND WHAT TO DO IF THE PROCEDURE FAILS

Adenoidectomy, usually combined with tonsillectomy in cases of sleep apnea, has an excellent success rate. Studies have demonstrated long-term improved quality of life for these patients. Newer data suggest that sleep apnea may negatively contribute to certain conditions such as attention deficit hyperactivity disorder (ADHD) and correction of the apnea leads to lower disease severity and reduced medication usage. The most critical aspect of early success is the complete removal of obstructing tissue. Because of this, the authors recommend visual inspection of the adenoid bed even if the technique to remove the adenoids was a blind one. In patients whose symptoms return several months to years after the initial procedure, adenoid regrowth must be considered. An article by Emerick and Cunningham sheds light on a potentially overlooked cause of recurrent symptoms, hypertrophy of the tubal tonsils. Tubal tonsils, also known as Gerlach tonsils, are found beneath the mucosa in the region of the torus tubarius. Hypertrophy of this tissue has been shown to cause symptoms similar to those of adenoid hypertrophy. In this study, tubal tonsils were ablated using suction cautery.

If symptoms do not resolve following successful surgery, obstruction at other anatomic locations must be entertained.