1
Introduction
In the last 20 years the surgical management of obstructive sleep apnea (OSA) and snoring has seen a continuous expansion and refinement. As surgeons gained more information about airway mechanics and physiology, many new procedures have been developed that are tailored for reconstruction and stabilization of not only specific levels of the airway but also particular mechanisms of collapse within each level. Newer procedures tend to be less invasive or morbid, thus improving acceptance by patients, which if matched with improved outcomes, makes OSA surgery a reasonable alternative to other modalities for OSA management.
Uvulopalatopharyngoplasty (UPPP) was introduced by Fujita more than a quarter century ago, approximately 5 years before continuous positive airway pressure (CPAP) became commercially available and almost a decade before it was popularized in the United States. At that time UPPP along with midline glossectomy and tracheostomy were the only management options for OSA sufferers. The procedure was designed to enlarge and stabilize the retro-palatal airway, which is the most frequent site of airway collapse, and was performed in the vast majority of OSA patients seeking treatment. Due primarily to inadequate selection methods, its efficacy in significantly reducing the Apnea/Hypopnea Index (AHI) was low, although many patients improved subjectively. Refinement of methods of airway evaluation and better understanding of airway collapse mechanics improved patient selection, resulting in higher UPPP efficacy. Although UPPP (and modifications) is today usually performed as part of a multi-level reconstruction, its efficacy as an isolated procedure could be as high as 60% in a carefully selected group of patients.
Recent reports on variations of retro-palatal anatomy and pathophysiology indicate that stenosis in this region can be present at different levels. To better understand this concept the reader is referred to the recent work of B. Tucker Woodson in which he classifies anatomic variations of the retro-palatal region, the “pharyngeal isthmus,” and their significance in selecting the appropriate surgical approach.
Briefly the retro-palatal region can be stenotic:
- •
Proximally, at the level of the hard palate
- •
Distally at the free end of the soft palate
- •
At both levels ( Fig. 32.1A and B )
FIG. 32.1
(A) Retro-palatal anatomy depicting proximal stenosis. Note relative parallel orientation of the soft palate to the posterior pharyngeal wall. (B) Retropalatal anatomy depicting distal stenosis. Note oblique orientation of the soft palate to the posterior pharyngeal wall.
In addition, many patients display hypertrophy and collapse of the lateral nasopharyngeal and oropharyngeal walls. The UPPP described here targets primarily stenosis at the distal end of the soft palate and to a limited degree of the lateral pharyngeal walls. It is then conceivable that this procedure will not be appropriate in patients with other types of retro-palatal stenosis.
In the last few years several new procedures that target specific areas of the retro-palatal airway have been proposed. These procedures carry descriptive names (lateral pharyngoplasty, palatal advancement, etc.). In this sense the term UPPP appears generic and perhaps it should be replaced with a different more descriptive term. Until then, however, OSA surgeons should keep in mind that UPPP addresses only a specific part of the retro-palatal airway and belongs in a group of procedures designed to reconstruct and stabilize this region.
2
Patient Selection
Generally there are no widely accepted criteria or algorithms for patient selection in any OSA surgery. Theoretically candidates for this procedure are patients who have stenosis only at the level of the distal end of the soft palate. The “classical UPPP” is primarily designed to expand and stabilize the distal “pharyngeal isthmus” and, to some degree, the lateral pharyngeal walls. If there is significant hypertrophy of the lateral pharyngeal walls, the UPPP procedure alone will not be adequate in addressing the problem.
Candidates for the “classical UPPP” should display the following findings on physical examination and fiber-optic endoscopy:
- •
An oblique orientation of the soft palate in relation to the posterior pharyngeal wall.
- •
Evidence of narrowing of the distal retro-palatal region on indirect mirror examination.
- •
A funnel-like appearance of the retro-palatal airway on fiber-optic examination during quiet breathing.
- •
Relatively normal lateral pharyngeal walls. Tonsillar hyperplasia is not considered a contraindication, as the tonsils, if present, are removed routinely during this procedure. Not infrequently, after removal, enlarged tonsils are determined to be much smaller than originally thought, as medialized lateral pharyngeal wall hyperplasia may mislead the observer. In such cases a lateral wall expansion procedure should be performed concurrently with the traditional UPPP.
Lateral cephalometric imaging is also very helpful in the airway evaluation of all OSA surgical candidates and should be requested when feasible. Cephalometry, although a static, upright, and awake technique, is simple, inexpensive, and offers valuable information about the upper airway anatomy. It will demonstrate the soft and hard palate orientation and the position of the maxilla in relation to the posterior pharyngeal wall more accurately than the physical and endoscopic examination, albeit in the sitting position. Cephalometry will also provide significant information about the position and size of the tongue and possible skeletal abnormalities compromising the retro-glottal airway. However, cephalometry is not routinely performed, possibly because of lack of awareness of its utility, unavailability in some centers, and third-party reimbursement issues.
The UPPP technique has undergone significant alterations since its introduction. An initially relatively conservative resection as proposed by Fujita et al. was followed by more aggressive procedures. Due to the relative lack of understanding of the pathophysiology and pharyngeal collapse mechanics, it was felt that a maximum resection of the soft palate without causing permanent velopharyngeal insufficiency was appropriate. This resulted in significant morbidity; in addition to the low efficacy and indiscriminate utilization by many surgeons, UPPP was stigmatized as useless and harmful. The pendulum has now swung in the other direction. Newer palatal procedures tend to emphasize tissue movement and fixation rather than resection. They are more respectful of the region’s physiology and address specific regional anatomy, thus becoming less morbid and more effective.
In this new era of OSA, palatopharyngeal surgery emphasis is placed on avoiding aggressive resection at the center of the soft palate and uvula. The procedure enlarges the retro-palatal airway by fixating the posterior pillar/palatopharyngeous muscle complex laterally while simultaneously pulling the free end of the palate away from the posterior pharyngeal wall.
Technique
The technique presented here is a modification of the one presented in the first edition of this book and emphasizes preservation of the uvula and the mucosa of the free end of the palate, unless the structures are too redundant. The procedure is performed under general anesthesia. The anesthesiology staff should be alerted to the diagnosis and the likelihood of difficult intubation. Administration of narcotics should be kept to a minimum because of the likelihood of respiratory obstruction and depressed respiratory drive after extubation. Dexamethasone and broad-spectrum antibiotics are administered IV preoperatively.
Step 1:
Lateral Pharynx
Following oro-tracheal intubation and deep muscle relaxation the mouth gag is positioned. This provides adequate visualization and exposure. Infiltration of the local mucosa with 3 to 4 mL of 0.5% bupivacaine or 1% lidocaine with 1/100,000 epinephrine solution is performed.
The incision is first outlined with a needle-tip electrocautery on the anterior pillars and, if needed, on the soft palate. Starting either on the right or the left, an incision is made with electrical cautery in a curvilinear fashion on the most lateral aspect of the anterior pillar to resect a generous portion of the underlying palatoglossus muscle. The incision curves gently toward the lateral aspect of the distal end of the soft palate. If conservative resection of the distal end of the soft palate is deemed necessary, the incision continues on the soft palate 5 to 10 mm from its end ( Fig. 32.2 ). The tonsils are then dissected in routine fashion and removed. Attention is paid to preserve as much mucosa of the posterior pillar as possible along with the palatopharyngeus muscle to be used for resurfacing of the lateral pharyngeal walls. In cases of palatopharyngeus muscle hypertrophy, this structure will be utilized for a modification of lateral pharyngoplasty to be performed in conjunction with the UPPP.
