Clinical Review & Education Clinical Challenges in Otolaryngology
Invited Commentary CLINICAL CHALLENGES IN OTOLARYNGOLOGY
Surgical Evaluation in Obstructive Sleep Apnea Climbing the Steep Part of the Learning Curve Eric J. Kezirian, MD, MPH
Many physiologic factors contribute to obstructive sleep apnea (OSA), including pharyngeal anatomy, dilator muscle activation, lung volumes, arousal threshold, and ventilatory control.1 Although it may be possible to examine the relative importance of these facRelated article page 565 tors in research settings, there are no clinically available tests that can be used to treat patients accordingly (for example, using a sedative hypnotic agent for those patients with a low arousal threshold). Surgery is an anatomical treatment, and Woodson2 summarizes the evidence regarding identification of the pattern of obstruction and surgical treatment of OSA. The first relevant issue is how to predict outcomes of palate surgery with tonsillectomy. Higher-level evidence from cohort studies indicates that Friedman stage shows the clearest association with outcomes after uvulopalatopharyngoplasty (UPPP). There are conflicting studies about the relative value of endoscopy and the Mueller maneuver during wakefulness, but Iwanaga et al3 and Hessel and Vries4 showed that druginduced sleep endoscopy (DISE) is also associated with UPPP outcomes. Comparison of findings from evaluation methods has not been undertaken as extensively for alternative palate procedures. This is important because some of these procedures (expansion sphincter pharyngoplasty, lateral pharyngoplasty) have demonstrated better outcomes than UPPP in randomized trials and because only 10% of OSA cases are Friedman stage 1. The second key issue is how to select alternative or adjunctive treatments and whether the findings predict outcomes. Most of the literature regarding evaluation methods has focused on findings that are associated with worse outARTICLE INFORMATION Author Affiliation: Department of Otolaryngology–Head & Neck Surgery, Keck School of Medicine of the University of Southern California, Los Angeles. Corresponding Author: Eric J. Kezirian, MD, MPH, Department of Otolaryngology–Head and Neck Surgery, Keck School of Medicine of the University of Southern California, 1520 San Pablo St, Ste 4600, Los Angeles, CA 90033 (Eric.Kezirian@med .usc.edu). Published Online: May 1, 2014. doi:10.1001/jamaoto.2014.555. Conflict of Interest Disclosures: Dr Kezirian has served on the medical advisory board and as consultant for Apnex Medical and ReVENT Medical; he has served as a consultant for Inspire Medical Systems and Split Rock Scientific and holds equity
568
comes, identifying mandible position (eg, SNB [sellanasion-B point] angle on the lateral cephalogram) and body mass index as factors associated with outcomes for all hypopharyngeal or retroglossal procedures. DISE may identify specific structures (VOTE classification) that contribute specifically to obstruction, but no studies have prospectively used DISE to select procedures. However, there are cohort studies showing that specific DISE findings are associated with worse outcomes after surgery,5,6 mandibular repositioning appliance use, or hypoglossal nerve stimulation. In my own practice, I use Friedman stage to select patients for isolated palate surgery and complement this with awake endoscopy for a more detailed evaluation of the pharynx. Instead of using DISE as a routine separate evaluation for all patients, as is done in some European centers, I prefer to use it as a stand-alone evaluation in approximately 20% of patients where I believe that it can change recommendations, such as those with previous surgery or an especially unclear pattern of obstruction. In some cases, I will perform DISE at the time of a procedure to guide the selection of a specific palate surgery technique or the extent of tongue base tissue resection, but this is based on personal experience rather than anything approaching a randomized trial. Woodson2 correctly describes that the surgical evaluation of OSA surgery remains in its infancy. Current techniques that evaluate physical anatomy may be combined with physiologic measures such as pharyngeal critical closing pressure. As novel technologies and techniques for treatment become available, so too will major advances in sleep surgery with larger, controlled, and prospective studies of evaluation methods. Both areas have proven essential in our quest to select procedures and enable targeted, effective, and predictable outcomes.
interest in Split Rock Scientific and Berendo Scientific; he also holds intellectual property rights with Berendo Scientific and Magnap.
4. Hessel NS, Vries N. Increase of the apnoea-hypopnoea index after uvulopalatopharyngoplasty: analysis of failure. Clin Otolaryngol Allied Sci. 2004;29(6):682-685.
REFERENCES
5. Koutsourelakis I, Safiruddin F, Ravesloot M, Zakynthinos S, de Vries N. Surgery for obstructive sleep apnea: sleep endoscopy determinants of outcome. Laryngoscope. 2012;122(11):2587-2591.
1. White DP. Pathogenesis of obstructive and central sleep apnea. Am J Respir Crit Care Med. 2005;172(11):1363-1370. 2. Woodson BT. Diagnosing the correct site of obstruction in newly diagnosed obstructive sleep apnea [published online May 1, 2014]. JAMA Otolaryngol Head Neck Surg. doi:10.1001/jamaoto .2014.546.
6. Soares D, Sinawe H, Folbe AJ, et al. Lateral oropharyngeal wall and supraglottic airway collapse associated with failure in sleep apnea surgery. Laryngoscope. 2012;122(2):473-479.
3. Iwanaga K, Hasegawa K, Shibata N, et al. Endoscopic examination of obstructive sleep apnea syndrome patients during drug-induced sleep. Acta Otolaryngol Suppl. 2003;(550):36-40.
JAMA Otolaryngology–Head & Neck Surgery June 2014 Volume 140, Number 6
Copyright 2014 American Medical Association. All rights reserved.
Downloaded From: http://archotol.jamanetwork.com/ by a University of Texas at Austin User on 06/07/2015
jamaotolaryngology.com
Invited Commentary CLINICAL CHALLENGES IN OTOLARYNGOLOGY
Surgical Evaluation in Obstructive Sleep Apnea Climbing the Steep Part of the Learning Curve Eric J. Kezirian, MD, MPH
Many physiologic factors contribute to obstructive sleep apnea (OSA), including pharyngeal anatomy, dilator muscle activation, lung volumes, arousal threshold, and ventilatory control.1 Although it may be possible to examine the relative importance of these facRelated article page 565 tors in research settings, there are no clinically available tests that can be used to treat patients accordingly (for example, using a sedative hypnotic agent for those patients with a low arousal threshold). Surgery is an anatomical treatment, and Woodson2 summarizes the evidence regarding identification of the pattern of obstruction and surgical treatment of OSA. The first relevant issue is how to predict outcomes of palate surgery with tonsillectomy. Higher-level evidence from cohort studies indicates that Friedman stage shows the clearest association with outcomes after uvulopalatopharyngoplasty (UPPP). There are conflicting studies about the relative value of endoscopy and the Mueller maneuver during wakefulness, but Iwanaga et al3 and Hessel and Vries4 showed that druginduced sleep endoscopy (DISE) is also associated with UPPP outcomes. Comparison of findings from evaluation methods has not been undertaken as extensively for alternative palate procedures. This is important because some of these procedures (expansion sphincter pharyngoplasty, lateral pharyngoplasty) have demonstrated better outcomes than UPPP in randomized trials and because only 10% of OSA cases are Friedman stage 1. The second key issue is how to select alternative or adjunctive treatments and whether the findings predict outcomes. Most of the literature regarding evaluation methods has focused on findings that are associated with worse outARTICLE INFORMATION Author Affiliation: Department of Otolaryngology–Head & Neck Surgery, Keck School of Medicine of the University of Southern California, Los Angeles. Corresponding Author: Eric J. Kezirian, MD, MPH, Department of Otolaryngology–Head and Neck Surgery, Keck School of Medicine of the University of Southern California, 1520 San Pablo St, Ste 4600, Los Angeles, CA 90033 (Eric.Kezirian@med .usc.edu). Published Online: May 1, 2014. doi:10.1001/jamaoto.2014.555. Conflict of Interest Disclosures: Dr Kezirian has served on the medical advisory board and as consultant for Apnex Medical and ReVENT Medical; he has served as a consultant for Inspire Medical Systems and Split Rock Scientific and holds equity
568
comes, identifying mandible position (eg, SNB [sellanasion-B point] angle on the lateral cephalogram) and body mass index as factors associated with outcomes for all hypopharyngeal or retroglossal procedures. DISE may identify specific structures (VOTE classification) that contribute specifically to obstruction, but no studies have prospectively used DISE to select procedures. However, there are cohort studies showing that specific DISE findings are associated with worse outcomes after surgery,5,6 mandibular repositioning appliance use, or hypoglossal nerve stimulation. In my own practice, I use Friedman stage to select patients for isolated palate surgery and complement this with awake endoscopy for a more detailed evaluation of the pharynx. Instead of using DISE as a routine separate evaluation for all patients, as is done in some European centers, I prefer to use it as a stand-alone evaluation in approximately 20% of patients where I believe that it can change recommendations, such as those with previous surgery or an especially unclear pattern of obstruction. In some cases, I will perform DISE at the time of a procedure to guide the selection of a specific palate surgery technique or the extent of tongue base tissue resection, but this is based on personal experience rather than anything approaching a randomized trial. Woodson2 correctly describes that the surgical evaluation of OSA surgery remains in its infancy. Current techniques that evaluate physical anatomy may be combined with physiologic measures such as pharyngeal critical closing pressure. As novel technologies and techniques for treatment become available, so too will major advances in sleep surgery with larger, controlled, and prospective studies of evaluation methods. Both areas have proven essential in our quest to select procedures and enable targeted, effective, and predictable outcomes.
interest in Split Rock Scientific and Berendo Scientific; he also holds intellectual property rights with Berendo Scientific and Magnap.
4. Hessel NS, Vries N. Increase of the apnoea-hypopnoea index after uvulopalatopharyngoplasty: analysis of failure. Clin Otolaryngol Allied Sci. 2004;29(6):682-685.
REFERENCES
5. Koutsourelakis I, Safiruddin F, Ravesloot M, Zakynthinos S, de Vries N. Surgery for obstructive sleep apnea: sleep endoscopy determinants of outcome. Laryngoscope. 2012;122(11):2587-2591.
1. White DP. Pathogenesis of obstructive and central sleep apnea. Am J Respir Crit Care Med. 2005;172(11):1363-1370. 2. Woodson BT. Diagnosing the correct site of obstruction in newly diagnosed obstructive sleep apnea [published online May 1, 2014]. JAMA Otolaryngol Head Neck Surg. doi:10.1001/jamaoto .2014.546.
6. Soares D, Sinawe H, Folbe AJ, et al. Lateral oropharyngeal wall and supraglottic airway collapse associated with failure in sleep apnea surgery. Laryngoscope. 2012;122(2):473-479.
3. Iwanaga K, Hasegawa K, Shibata N, et al. Endoscopic examination of obstructive sleep apnea syndrome patients during drug-induced sleep. Acta Otolaryngol Suppl. 2003;(550):36-40.
JAMA Otolaryngology–Head & Neck Surgery June 2014 Volume 140, Number 6
Copyright 2014 American Medical Association. All rights reserved.
Downloaded From: http://archotol.jamanetwork.com/ by a University of Texas at Austin User on 06/07/2015
jamaotolaryngology.com
