Uvulopalatopharyngoplasty is a generally safe and widely accepted surgical procedure for the treatment of obstructive sleep apnea. Unfortunately, uvulopalatopharyngoplasty does not always result in success, and patients who initially experienced improvement in the severity of their obstructive sleep apnea may relapse. Proper patient selection and performing uvulopalatopharyngoplasty in conjunction with other surgical procedures that are directed at other sites of upper airway collapsibility may yield favorable outcomes.
Uvulopalatopharyngoplasty is a generally safe and widely accepted surgical procedure for the treatment of obstructive sleep apnea.
Unfortunately, uvulopalatopharyngoplasty (UPPP) does not always result in success, and patients who initially experienced improvement in the severity of their obstructive sleep apnea may relapse.
Proper patient selection and performing UPPP in conjunction with other surgical procedures that are directed at other sites of upper airway collapsibility may yield favorable outcomes.
The uvulopalatopharyngoplasty (UPPP) procedure was initially presented by Fujita and colleagues in 1981. It was explicitly intended to treat obstructive sleep apnea (OSA) by increasing the retropalatal airway and decreasing upper airway collapsibility. Numerous UPPP procedures were completed during the 1980s, although with variable outcomes in treating apnea. Sher and colleagues conducted a meta-analysis that showed a success rate of 40.8% for unselected patients when surgical success was defined as a postoperative apnea-hypopnea index (AHI) of less than 20 and at least a 50% reduction in the AHI from baseline. When evaluating selected patients, Larsson and colleagues demonstrated a success rate of 50% to 60%. UPPP increases the velopharynx by excising the posterior segment of the soft palate and uvula, by remodeling the anterior and posterior tonsillar pillars, and, if not already resected, extirpation of the tonsils.
After Fujita’s publication, various revisions of his procedure were introduced, but not a single one of them exhibited a significant enhancement in outcome. Recently, however, more modern alterations have displayed favorable results: coblation of the tonsils instead of a tonsillectomy; designing a uvulopalatal flap instead of excising the posterior segment of the soft palate and uvula; and using electrocautery.
The notion of multilevel airway surgery was developed as a corollary to the understanding that an isolated UPPP procedure is quite limited in effectively treating OSA. At present, UPPP is typically used concurrently with other surgical procedures because there are multiple sites of airway collapse in OSA patients.
Proper patient selection for UPPP surgery continues to be challenging. Although numerous methods exist for airway evaluation in OSA patients, most have a limited efficacy in forecasting success with UPPP. Initially, patient selection was based on disease severity as manifested by the AHI or the respiratory disturbance index (RDI). However, researchers showed that this traditional approach resulted in conflicting findings when evaluating UPPP success rates. Therefore, Friedman and colleagues introduced a staging system whereby OSA patients are classified into 3 groups based on anatomy, which includes the size of the tonsils, the position of the palate in relation to the tongue, and the body mass index (BMI).
The size of the tonsils is classified from 0 to 4. Grade 0 tonsils refer to tonsils that are resected. Grade 1 tonsils indicate that the tonsils are concealed within the tonsillar pillars. Grade 2 tonsils indicate that the tonsils reach the border of the tonsillar pillars. Grade 3 tonsils indicate that the tonsils spread past the pillars but do not reach the midline. Grade 4 tonsils indicate that the tonsils reach the midline.
The Friedman tongue position or Friedman palate position is a stratification scheme that allows for estimation of obstruction at the level of the hypopharynx and is a method that was established through modification of the Mallampati score. Evaluation of the palate is performed by having the patient open his or her mouth widely with the absence of tongue protrusion. Palate position 1 implies that the whole uvula is in view as well as the tonsils and tonsillar pillars. Palate position 2 implies that the uvula is perceived, whereas the tonsils are not. Palate position 3 implies that the uvula is not able to be viewed, leaving only the soft palate to be perceived. Palate position 4 implies that only the hard palate is in view.
The anatomic staging system developed by Friedman can be used as a dependable tool for anticipating the surgical outcome of UPPP and is useful in selecting patients for the procedure. Stage I classification includes patients with tonsil size 3 or 4, palate position 1 or 2, and a BMI less than 40. Patients who meet criteria for stage II classification have tonsil size 0, 1, or 2 with palate position 1 or 2, or tonsil size 3 or 4 with palate position 3 or 4, and a BMI less than 40. Stage III classification includes patients with tonsil size 0, 1, or 2 and palate position 3 or 4. In addition, a stage III designation is applied to all patients with a BMI greater than 40. Information obtained from the retrospective study conducted by Friedman and colleagues demonstrated that patients designated as stage I had a success rate of 80.6%; patients with a stage II classification had a success rate of 37.9%, and those with stage III reached a success rate of just 8.1%. These data suggest that stage I patients should proceed with UPPP, whereas stage III patients should not be treated with UPPP. The efficacy of surgical treatment with UPPP for patients who are stratified in the stage II category leaves much to be desired; therefore, these patients should be treated comparably to stage III patients.
Surgeons typically use data attained by physical examination, fiberoptic endoscopy, and lateral cephalometric analysis to evaluate the airway preoperatively. Elements of the physical examination that are salient include the following: Friedman tongue position, length of the uvula, size of the tonsils, existence of posterior pharyngeal folds, and the existence of pillar and palatal webbing. Endoscopic components include the following: orientation of the airway, position of the lateral pharyngeal wall, cross-section of the retrolingual and retropalatal airway, epiglottis position, and shape, and the existence of lingual tonsils. Important factors from cephalometric analysis are as follows: the existence of retrognathia, posterior airway space, soft palate length, including the uvula, and the distance from the mandibular plane to the hyoid ( Table 1 ).
|Posterior nasal spine to uvula tip distance||>38 mm|
|Tonsil size||+++ to ++++|
|Posterior airway space||>10 mm|
|Mandibular plane to hyoid distance||<27 mm|
|Friedman tongue position||I or II|
|Absence of retrognathia|
|Absence of retroglossia|
|Absence of hypopharyngeal narrowing|
|Absence of lateral pharyngeal wall bulging|
|Absence of morbid obesity||BMI >40|
|Absence of sagittal orientation of airway|
OSA patients who are deemed appropriate candidates for UPPP generally present with palatal redundancy, an elongated uvula, and enlarged tonsils while simultaneously not having an enlarged tongue, narrowing of the hypopharynx, or a BMI characteristic of morbid obesity. It is important to remember that most patients who undergo UPPP will require a multilevel approach in treating OSA.
Numerous modifications have been applied to UPPP surgery since it was first developed. The procedure has progressed gradually in consideration of the differences in physiology and anatomy of the pharynx, and to decrease morbidity. Predominantly, the surgical priority is to conservatively excise the uvula and soft palate and to resect a substantial amount of tissue from the lateral pharyngeal walls.
UPPP is completed under general anesthesia with orotracheal intubation. Because the probability of a difficult airway is high in OSA patients, the anesthesiology team should be informed of the diagnosis in case an awake fiberoptic intubation is required. An antibiotic with empiric coverage (ampicillin-sulbactam or clindamycin if the patient is allergic to penicillin) and a corticosteroid (dexamethasone or methylprednisolone) should be administered intravenously preoperatively. Because of the probability of ventilatory depression and obstruction of the airway postoperatively, opioid analgesics should be administered cautiously. The patient should be positioned with the neck extended and with a shoulder roll in place. , ,
The Crowe-Davis retractor with tongue blade is placed in order to attain suitable exposure and visualization. The surgical site is infiltrated with 1% lidocaine with epinephrine 1:100,000 to promote hemostasis. Care is taken not to distort the soft tissue architecture when injecting local anesthesia. The anterior tonsillar pillar incision is curved toward the base of the uvula in order to determine the amount of soft palate to be resected. This conservative approach leaves 5 to 10 mm of soft palate for excision. Electrical cautery is used to mark the incision at the lateral portion of the anterior pillar and at the ventral surface of the palate, which will allow for not only maximal removal of tissue from this site but also excision of the underlying palatoglossus muscle. Marking the incision is completed correspondingly on the opposite side while ensuring to curve when approaching the base of the uvula ( Fig. 1 ). , ,
A number 15 blade is used to complete the incision by connecting the markings. The initial dissection begins by separating the inferior tonsillar pole from the base of the tongue ( Fig. 2 ). Resection of the anterior tonsillar pillar, a segment of the palatoglossus muscle, and the palatine tonsil is performed in a retrograde manner. In order to remodel the lateral dimension of the pharyngeal wall, most of the posterior tonsillar pillar is preserved. Fibrous scar tissue will be present if the tonsils have been previously resected. This dense scar tissue in the tonsillar fossa must be cautiously dissected off the superior pharyngeal constrictor muscle because it will hinder the advancement of the posterior pillar. , ,
The dorsal or posterior mucosa flap should be left marginally prolonged when continuing the dissection on the soft palate. The ventral incision is directed approximately toward the base of the uvula once the uvula is reached. Partial excision of the uvular muscle is achieved by maintaining a prolonged posterior uvular flap. Care should be taken not to excessively pull on the uvula when transecting it, as that will result in an overly truncated uvula and disrupt the attachment between the uvular muscle and the levator palatini muscles. This muscular interruption diminishes the activity of the palatal sphincter and leads to complications with swallowing and speech. The dissection is then completed correspondingly on the opposite side and should be executed with electrical cautery. Next, forceps are used to retract the ventral mucosal flap, and a 1- to 2-cm inclined or sloping incision is performed bilaterally at the intersection of the dorsal palatal flap and the posterior tonsillar pillar ( Fig. 3 ). , ,