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Obstructive Sleep Apnea Surgery

The Academia Singapore 27-29 July

Abstract:

Obstructive sleep apnea syndrome (OSAS) is a collective term which also includes snoring and

upper airway resistance syndrome (UARS). Simply put, the term is descriptive of the effects of a

neurologic and anatomic partial collapse or total obstruction of the upper airway during sleep. The main

effects are excessive daytime sleepiness (EDS), impaired cognition, and increased risk of motor vehicle

accidents. The daytime sleepiness causes marked decrements in quality of life. Subjects with OSAS

often have cardiovascular morbidities, hypertension, diabetes, myocardial infarction, stroke and sudden

death. A shortened life span is common in subjects with untreated obstructive sleep apnea syndrome.

In addition, OSAS creates a significant public health burden, especially in light of the staggering

prevalence of this problem worldwide. In fact the extrapolated estimated global prevalence of OSAS is

estimated at 491 million of the entire population of 6.6 billion. In the United States alone the prevalence

in middle age men is 24% and women 9% with an overall prevalence of 4% men, 2% women. Less than

5% of those with OSAS are diagnosed or treated1.

The nocturnal obstructive process in sleep disorders may be localized to one or two areas, or

may encompass the entire upper airway passages. This includes the nasal cavity, nasopharynx,

oropharynx and hypopharynx. Conservative medical therapy is usually recommended first such as

weight loss, exercise, sleep hygiene, dental appliances and continuous positive airway pressure (CPAP).

Unfortunately, there is a significant compliance problem with medical devices used in the nasal region

(CPAP). There are surgical procedures presently available to provide for a logical upper airway

reconstruction of these regions in such a manner as to minimize the risks and possible complications.

A two-phased surgical protocol has been used to decrease the risk of over operating since

clinical outcomes are very difficult to predict. Hence, most surgeons, orthodontists and dentists will first

utilize the more conservative Phase I protocol. The genioglossus advancement procedure (Phase I or II)

may be used with or without combined hyoid myotomy and suspension. Phase II includes skeletal

surgery of the upper and lower arches known as bi-maxillary advancement [BMA] which is also referred

to as maxillary and mandibular osteotomy [MMO]. The most important part of the surgical work up for

OSAS is to establish the potential for obstruction at each level of the upper airway (nose, palate, tonsils,

and tongue base). A team approach including orthodontists and oral maxilla-facial surgeons determines

the “best practice” for each individual patient. Procedur

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Current evaluation techniques usually utilize three dimensional (3D) imaging computed

tomography (CT) with upright and supine studies which is a marked improvement in visualization, and

leads to improved treatment planning. Magnetic resonance imaging (MRI) is frequently used in sleep

research. MRI scanning can be done asleep with a polysomnogram (PSG) and provides substantial data,

but is lengthy and expensive2. These three dimensional methods provide more information than

traditional two dimensional (2D) radiographic imaging (Panorex and lateral Cephalometrics).

Fiberoptic endoscopy examinations can be performed awake or during drug-induced sleep

endoscopy (DISE) using Propofol sedation. For drug-induced sleep endoscopy the patient is under a

general anesthetic3. The fiberoptic scan gives valuable information of the airway including visual

imaging data of the airway at all levels. During sleep in patients with OSAS the airway narrows and

starts to obstruct. Negative pressures are then generated which can further cause total airway

obstruction. This process can be observed during sleep endoscopy. Used properly the technology could

assist in a clearer understanding of the partial or totally obstructed airway.

Our surgical colleagues, orthodontists and dentists have, for at least the last thirty years,

focused on various methods of managing the anatomic pharyngeal airway for patients with OSAS. It is

time to consider new methods for OSAS treatments. Other fields, even outside of medicine and

dentistry, may offer new technology or ideas not presently used in the evaluation and treatment of

OSAS disorders.

Despite the treatment options available today, or those that may be developed in the near

future, the etiology of OSAS remains unknown. We cannot continue to think only in terms of the

anatomic airway. For instance, consider the possibility that turbulent “airflow” may cause nightly

snoring and thus damage the delicate soft tissues of the upper airway. 4-10 We need to examine the

importance of “airflow characteristics” in the pharyngeal airway in OSAS11. I challenge the next

generation of sleep specialists to move beyond the present limitations of our thinking and consider the

airway and airflow as one single unit.

Long-Term Clinical Outcomes

Riley RW, Powell NB,Li KK, Troell RJ, Guilleminault C. Surgery and obstructive sleep apnea: Long-Term

Clinical Outcomes. Otolaryngology Head and Neck Surg. 2000 Mar; 122(3):415-21.

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Forty patients who underwent soft tissue and skeletal surgery were the subjects of this review.

Methods of evaluation included polysomnographic variables (respiratory disturbance index [RDI], low

oxyhemoglobin desaturation [LSAT], body mass index, quality-of-life assessments, roentgenographic

analysis. and complications. Statistical analysis used the SAS 6.12 system.

Thirty-six of 40 patients (90%) showed long-term clinical success. The mean preoperative RDI,

nasal continuous positive airway pressure RDI, and long-term RDI were 71.2 ±27.0, 7.6 ± 52 and 7.6 ±

5.1, respectively. The mean preoperative LSAT, nasal continuous positive airway pressure LSAT, were

67.5% ±14.8%, 87.1% ± 3.2%, and 86.3% ± 3.9%, respectively. The mean follow-up was 50.7±31.9

months. The patients showed a statistically significant long-term weight gain (P=0.0002) compared with

their 6-month postoperative level (body mass index 31-4± 6.7 vs 33.2±6.3). There was a positive

correlation with the amount of skeletal advancement and clinical outcome.

Risk Management

1. Patient is seen for a thorough preoperative evaluation.

2. Encourage the patient to have spouse, children and family members come to this meeting so they can

ask questions about the procedure along with the patient.

3. The pre op should be done in the office, as should the physical examination.

4. Most subjects, and especially those with OSAS, will need an ECG or a full cardiac study.

5. The surgical procedure is reviewed with the patient and members of his family in careful detail.

6. Each patient is entitled to understand the risks, indications, benefits, and alternatives for the

procedure. This includes, but is not limited to bleeding, infection; failure to correct the problem,

worsening of the condition, changes in smell, and aesthetic changes with may be unfavorable. Also,

there is the risk of death from anesthesia or surgery.

7. Post-operative care, medications, estimated length of time in the hospitable and follow-up after

discharge are also discussed.

8. The patient should be aware of the possible need for nasal CPAP in post-operative care. A

tracheotomy may be necessary on an emergency basis.

9. Questions and answers are completed for each procedure. Each patient is allowed to change their

mind at any time prior to surgery.

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This introduction is planned to be brief and the slides presented should help give a better

understanding of medical and surgical OSAS treatments. Surgical skeletal procedures will be part of the

MMA or BMA presentation.

References:

Epidemiology Study

1. Terry Young, Ph.D., Mari Palta, Ph.D., Jerone Dempsey, Ph.D., James Skatrud, M.D.,

Steven Weber, Ph.D., and Safwan Badr, M.D. The occurrence of sleep-disordered breathing among

middle –aged adults. N Engl J Med 1993;328:1230-5.

MRI and PSG 2. Shin LK, Holbrook AB, Capasso R, Kushida CA, Powell NB, Fischbein NJ, Pauly KD. Improved Sleep MRI

at 3 tesla in Patients with Obstructive Sleep Apnea. J Magn Reson Imaging 2013 Feb 6. Doi: 10

1002/jmri.24029, [Epub ajead pf print] Department of Radiology, Stanford University, Stanford,

California, USA; Palo Alto Health Care System,, Palo Alto, California.

Fiberoptic Endoscopy

3. Eric J. Kezirian, MD. Nonresponders to pharyngeal surgery for obstructive sleep apnea: Insights from

drug-induced sleep endoscopy. Laryngoscope. 2011 June; 121(6):1320-1326.:1320-1326.

Turbulent Vibrations of the Pharyngeal Airway

4. Friberg D, Ansved T, Borg K, Carlsson-Nordlander B, Larsson H, Svanborg E.

Histological indications of a progressive snorers’ disease in an upper airway

muscle. Ann J Respir Crit Care Med 1998;157:586–93.

5. Woodson BT, Garancis JC, Toohill RJ. Histopathologic changes in snoring and

obstructive sleep apnea syndrome. Laryngoscope 1991;101:1318–22.

6. Namystowski G, Scierski W, Zembala-Nozynska E, Nozynska J, Misiolek M.

Histopathologic changes of the soft palate in snoring and obstructive sleep

apnea syndrome patients. Otolaryngol Pol 2005;59(1):3–19.

7. Paulson F, Phillip P, Tsokos M, Jungmann K, Muller A, Verse T, et al.1 Upper airway epithelial structural

changes in obstructive sleep-disoriented

breathing. Am J Respir Crit Care Med 2002;166:501–9.

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8. Wasserman D, Badger D, Doyl L. Industrial vibration and overview. J Am Soc

Safety Eng 1974;19:38–43.

9. Curry BD, Bain JL, Yanji G, Zhang LL, Yamaguchi M, Matloub HS, et al. Vibration

injury damages arterial endothelial cells. Muscle Nerve 2002;25:527–34.

10. Govindaraju SR, Curry BD, Bain JL, Riley DA. Comparison of continuous

vibration effects on rat-tail artery and nerve. Muscle Nerve 2006;34(2):

197–204.

11. Nelson B. Powell, Mihai Mihaescu, Goutham Myavarapu, Edward M. Weaver,

Christian Guilleminault, Ephraim Gutmark. Patterns in pharyngeal airflow associated with

Sleep-disordered breathing. Sleep Medicine 12 (2011):966-974

Nelson B. Powell M.D., D.D.S.