Sleep Apnea Syndromes: Morgenthaler TI

Morgenthaler TI, Aurora RN, Brown T, Zak R, Alessi C, Boehlecke B, Chesson AL, Friedman L, Kapur V, Maganti R, Owens J, Pancer J, Swick TJ, Anonymous00064, Anonymous00065. · Mayo Clinic, Rochester MN, USA. · Sleep. · Pubmed #18220088 links to  free full text

Abstract: These practice parameters are an update of the previously published recommendations regarding the use of autotitrating positive airway pressure (APAP) devices for titrating pressures and treating adult patients with obstructive sleep apnea syndrome. Continuous positive airway pressure (CPAP) at an effective setting verified by attended polysomnography is a standard treatment for obstructive sleep apnea (OSA). APAP devices change the treatment pressure based on feedback from various patient measures such as airflow, pressure fluctuations, or measures of airway resistance. These devices may aid in the pressure titration process, address possible changes in pressure requirements throughout a given night and from night to night, aid in treatment of OSA when attended CPAP titration has not or cannot be accomplished, or improve patient comfort. A task force of the Standards of Practice Committee of the American Academy of Sleep Medicine has reviewed the literature published since the 2002 practice parameter on the use of APAP. Current recommendations follow: (1) APAP devices are not recommended to diagnose OSA; (2) patients with congestive heart failure, patients with significant lung disease such as chronic obstructive pulmonary disease; patients expected to have nocturnal arterial oxyhemoglobin desaturation due to conditions other than OSA (e.g., obesity hypoventilation syndrome); patients who do not snore (either naturally or as a result of palate surgery); and patients who have central sleep apnea syndromes are not currently candidates for APAP titration or treatment; (3) APAP devices are not currently recommended for split-night titration; (4) certain APAP devices may be used during attended titration with polysomnography to identify a single pressure for use with standard CPAP for treatment of moderate to severe OSA; (5) certain APAP devices may be initiated and used in the self-adjusting mode for unattended treatment of patients with moderate to severe OSA without significant comorbidities (CHF, COPD, central sleep apnea syndromes, or hypoventilation syndromes); (6) certain APAP devices may be used in an unattended way to determine a fixed CPAP treatment pressure for patients with moderate to severe OSA without significant comorbidities (CHF, COPD, central sleep apnea syndromes, or hypoventilation syndromes); (7) patients being treated with fixed CPAP on the basis of APAP titration or being treated with APAP must have close clinical follow-up to determine treatment effectiveness and safety; and (8) a reevaluation and, if necessary, a standard attended CPAP titration should be performed if symptoms do not resolve or the APAP treatment otherwise appears to lack efficacy.

Morgenthaler TI, Kapen S, Lee-Chiong T, Alessi C, Boehlecke B, Brown T, Coleman J, Friedman L, Kapur V, Owens J, Pancer J, Swick T, Anonymous00044, Anonymous00045. · Sleep Disorders Center, Pulm Crit Care Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA. · Sleep. · Pubmed #16944671 No free full text.

Abstract: Therapies for obstructive sleep apnea other than positive airway pressure, oral appliances, and surgical modifications of the upper airway are reviewed in this practice parameter. Several of these therapies such as weight loss and positional therapy hold some promise. Others, such as serotonergic agents, may gain credibility in the future but lack well-designed clinical trials. No practice parameters could be developed for a number of possible therapeutic modalities that had little or no evidence-based data on which to form a conclusion. The role of an organized, targeted weight-loss program either as a single therapy or as a supplement to PAP needs to be clarified. Although bariatric surgery is increasingly performed for refractory medically complicated obesity, its long-term effectiveness in treatment of obstructive sleep apnea in morbidly obese patients is not yet demonstrated. Positional therapy, or methods for preventing sleep in the supine position, has probably been underutilized due to lack of easily measured predictive factors and randomized controlled trials.

Kushida CA, Littner MR, Hirshkowitz M, Morgenthaler TI, Alessi CA, Bailey D, Boehlecke B, Brown TM, Coleman J, Friedman L, Kapen S, Kapur VK, Kramer M, Lee-Chiong T, Owens J, Pancer JP, Swick TJ, Wise MS, Anonymous00039. · Stanford University Center of Excellence for Sleep Disorders, Stanford, CA, USA. · Sleep. · Pubmed #16553024 No free full text.

Abstract: Positive airway pressure (PAP) devices are used to treat patients with sleep related breathing disorders (SRBD) including obstructive sleep apnea (OSA). Currently, PAP devices come in three forms: (1) continuous positive airway pressure (CPAP), (2) bilevel positive airway pressure (BPAP), and (3) automatic self-adjusting positive airway pressure (APAP). After a patient is diagnosed with OSA, the current standard of practice involves performing full, attended polysomnography during which positive pressure is adjusted to determine optimal pressure for maintaining airway patency. This titration is used to find a fixed single pressure for subsequent nightly usage. A task force of the Standards of Practice Committee of the American Academy of Sleep Medicine reviewed the available literature. Based on this review, the Standards of Practice Committee developed these practice parameters as a guideline for using CPAP and BPAP appropriately (an earlier review and practice parameters for APAP was published in 2002). Major conclusions and current recommendations are as follows: 1) A diagnosis of OSA must be established by an acceptable method. 2) CPAP is effective for treating OSA. 3) Full-night, attended studies performed in the laboratory are the preferred approach for titration to determine optimal pressure; however, split-night, diagnostic-titration studies are usually adequate. 4) CPAP usage should be monitored objectively to help assure utilization. 5) Initial CPAP follow-up is recommended during the first few weeks to establish utilization pattern and provide remediation if needed. 6) Longer-term follow-up is recommended yearly or as needed to address mask, machine, or usage problems. 7) Heated humidification and a systematic educational program are recommended to improve CPAP utilization. 8) Some functional outcomes such as subjective sleepiness improve with positive pressure treatment in patients with OSA. 9) CPAP and BPAP therapy are safe; side effects and adverse events are mainly minor and reversible. 10) BPAP may be useful in treating some forms of restrictive lung disease or hypoventilation syndromes associated with hypercapnia.

Kushida CA, Morgenthaler TI, Littner MR, Alessi CA, Bailey D, Coleman J, Friedman L, Hirshkowitz M, Kapen S, Kramer M, Lee-Chiong T, Owens J, Pancer JP, Anonymous00038. · Stanford University Center of Excellence for Sleep Disorders, CA, USA. · Sleep. · Pubmed #16494092 No free full text.

Abstract: These practice parameters are an update of the previously published recommendations regarding use of oral appliances in the treatment of snoring and Obstructive Sleep Apnea (OSA). Oral appliances (OAs) are indicated for use in patients with mild to moderate OSA who prefer them to continuous positive airway pressure (CPAP) therapy, or who do not respond to, are not appropriate candidates for, or who fail treatment attempts with CPAP. Until there is higher quality evidence to suggest efficacy, CPAP is indicated whenever possible for patients with severe OSA before considering OAs. Oral appliances should be fitted by qualified dental personnel who are trained and experienced in the overall care of oral health, the temporomandibular joint, dental occlusion and associated oral structures. Follow-up polysomnography or an attended cardiorespiratory (Type 3) sleep study is needed to verify efficacy, and may be needed when symptoms of OSA worsen or recur. Patients with OSA who are treated with oral appliances should return for follow-up office visits with the dental specialist at regular intervals to monitor patient adherence, evaluate device deterioration or maladjustment, and to evaluate the health of the oral structures and integrity of the occlusion. Regular follow up is also needed to assess the patient for signs and symptoms of worsening OSA. Research to define patient characteristics more clearly for OA acceptance, success, and adherence is needed.

Morgenthaler TI. · No affiliation provided · Sleep Med. · Pubmed #18706853 No free full text.

This publication has no abstract.

Caples SM, Rosen CL, Shen WK, Gami AS, Cotts W, Adams M, Dorostkar P, Shivkumar K, Somers VK, Morgenthaler TI, Stepanski EJ, Iber C. · Mayo Clinic College of Medicine, Rochester, MN, USA. · J Clin Sleep Med. · Pubmed #17557424 No free full text.

Abstract: Standardized guidelines for polysomnography (PSG) have not specified methods for acquiring or interpreting electrocardiographic (ECG) data. The practice of single lead ECG monitoring during PSG may allow identification of simple measures of cardiac rhythm but reduces the ability to detect myocardial ischemia and to define cardiac intervals. Although simple measures of cardiac rhythm such as heart rate and cardiac pauses are inherently reliable, there is limited data regarding outcome measures relative to sleep related heart rates and cardiac events during sleep. Several observational and cross-sectional studies demonstrate that average heart rate drops nearly 50% from infancy through young adulthood and that the average heart rate slows during sleep compared with wakefulness; the definitions of sinus bradycardia and sinus tachycardia should therefore be lower during sleep than wakefulness. Asystoles of up to 2 seconds are seen in normal populations during sleep. Although there may be an increased risk of certain arrhythmias at night, particularly in sleep disordered breathing, there is no evidence that supports different definitions for these arrhythmias during sleep compared with wakefulness. When the quality of tracings permits, the standard definitions of narrow- and wide-complex tachycardias and atrial fibrillation may be employed. In the future, expansion to multiple ECG leads and the use of alternative tools may provide better definition of heart rates and cardiac events during sleep.

Olson EJ, Park JG, Morgenthaler TI. · Mayo Clinic College of Medicine, Division of Pulmonary and Critical Care Medicine, Mayo Sleep Disorders Center, 200 1st Street SW, Rochester, MN 55905, USA. · Prim Care. · Pubmed #15935189 No free full text.

Abstract: OSAHS should be an expected condition in many patients encountered by primary care providers. The diagnosis may arise because of patient daytime dysfunction, partner prompting, or in the course of managing comorbidities adversely influenced by the hemodynamic, neural, humoral,and inflammatory consequences of repetitive desaturations and arousals.OSAHS should be suspected in patients who exhibit habitually loud snoring, witnessed apneas/choking/gasping during sleep, hypertension, neck circumferences of 17 inches or greater, obesity, and laterally narrowed oropharynxes. Diagnosis is established by polysomnography. CPAP is the treatment of choice for most patients. Education, follow-up, and heated humidification may help bolster compliance. Lifestyle modifications, oral appliances, and upper surgeries are additional treatment options.

Barnes TW, Olsen KD, Morgenthaler TI. · Division of Pulmonary and Critical Care Medicine, Mayo Clinic College of Medicine, Desk East 18, Mayo Clinic, 200 1st St SW, Rochester, MN 55905, USA. · Sleep Med. · Pubmed #15511710 No free full text.

Abstract: Lingual thyroid has been reported to cause obstructive sleep apnea (OSA) only once in the literature. We present a case of a 49-year-old nonobese female with a 2-year history of progressive snoring, apneas, snort arousals, and daytime somnolence associated with the sensation of an 'enlarging tongue'. She was found to have severe OSA caused by a large lingual thyroid. While positive airway pressure therapy was not successful, surgical resection of the thyroid was curative. OSA caused by lingual thyroid and other oropharyngeal/parapharyngeal tumors are discussed. A careful oropharyngeal examination is important in evaluating patients with complaints of OSA.

Olson EJ, Moore WR, Morgenthaler TI, Gay PC, Staats BA. · Sleep Disorders Center, Division of Pulmonary and Critical Care Medicine and Internal Medicine, Mayo Clinic, Rochester, Minn 55905, USA. · Mayo Clin Proc. · Pubmed #14661684 links to  free full text

Abstract: Obstructive sleep apnea-hypopnea syndrome (OSAHS) is characterized by repetitive episodes of airflow reduction (hypopnea) or cessation (apnea) due to upper airway collapse during sleep. Increasing recognition and a greater understanding of the scope of this condition have substantially affected the practices of many clinicians. This review provides practical information for physicians assessing patients with OSAHS. It discusses complications, clinical recognition, the polysomnographic report, and treatment of OSAHS, including strategies for troubleshooting problems associated with continuous positive airway pressure therapy.

Kuzniar TJ, Golbin JM, Morgenthaler TI. · Sleep Disorders Center, Division of Pulmonary and Critical Care Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA. · Sleep Breath. · Pubmed #17541664 No free full text.

Abstract: There is no universally accepted method to determine effective therapy for central sleep apnea (CSA). Continuous positive airway pressure (CPAP) applied acutely most often does not eliminate apneas and hypopneas. We hypothesized that the application of two or more therapeutic modalities after the diagnostic phase of polysomnography, a multi-modality titration study (MMTS), would identify a successful CSA treatment more often than a standard split-night study (SNS) and obviate the need for additional polysomnograms to determine a successful therapy. We retrospectively analyzed polysomnograms of patients diagnosed with CSA at our Sleep Disorders Center. We defined a therapy trial that resulted in an apnea-hypopnea index < 10 with at least one treatment modality as a therapeutic success. One hundred fifteen patients with CSA were studied. Sixty-six patients (57.4%) underwent a SNS, and 49 patients (42.6%) underwent a MMTS. SNS yielded only 8/66 (12.1%) successes on the first night, whereas a MMTS yielded 19/49 (38.8%) successes (p = 0.001, two-tailed Fishers exact). Patients who underwent a SNS eventually had similar rate of success as patients studied with MMTS (60.6 vs 63.3%, NS), but required more testing. Adaptive servo-ventilation was the most successful modality tested, yielding 36/46 (78.3%) successes. Trials of additional modalities following a failed trial of CPAP often produce a successful option that may guide therapy in patients with CSA. This approach may lead to establishing the diagnosis and treatment plans faster, while reducing unnecessary testing.

Kuźniar TJ, Morgenthaler TI, Prakash UB, Pallanch JF, Silber MH, Tippmann-Peikert M. · Sleep Disorders Center, Mayo Clinic College of Medicine, Rochester, MN 55905, USA. · J Clin Sleep Med. · Pubmed #19317384 No free full text.

Abstract: The presence of stridor in patients with multiple system atrophy (MSA) is associated with poor prognosis, mainly due to a high risk of complete airway obstruction at night. Continuous positive airway pressure (CPAP) therapy has been proposed as a treatment of MSA-associated stridor, but, until now, there has been no visual documentation of the effect of CPAP on laryngeal patency during nonpharmacologically induced spontaneous sleep of a patient with MSA. We present a video-laryngoscopic documentation of a 57-year-old woman with MSA who was evaluated for nocturnal stridor. Direct laryngoscopy during sleep without pharmacologic sedation documented inspiratory adduction of the vocal cords with downward displacement of the larynx. Application of CPAP resulted in improvement of stridor, distension of the hypopharynx, abduction of vocal cords, and reduction of the downward displacement of the larynx. We discuss the possible mechanisms of action of CPAP in MSA-associated stridor.

Morgenthaler TI. · Mayo Clinic Center for Sleep Medicine, Division of Pulmonary and Critical Care Medicine, Mayo Clinic, Rochester, MN 55905, USA. · J Clin Sleep Med. · Pubmed #18763422 links to  free full text

This publication has no abstract.

Kuzniar TJ, Morgenthaler TI. · Division of Pulmonary and Critical Care Medicine, Evanston Northwestern Healthcare, Evanston, IL 60201, USA. · J Clin Sleep Med. · Pubmed #18595442 links to  free full text

This publication has no abstract.

Allam JS, Olson EJ, Gay PC, Morgenthaler TI. · Division of Pulmonary and Critical Care Medicine and Mayo Clinic Sleep Disorders Center, 200 First St SW, Rochester, MN 55905, USA. · Chest. · Pubmed #18079219 links to  free full text

Abstract: BACKGROUND: Complex sleep apnea syndrome (CompSAS) is recognized by the concurrence of mixed or obstructive events with central apneas, the latter predominating on exposure to continuous positive airway pressure (CPAP). Treatment of CompSAS or central sleep apnea (CSA) syndrome with adaptive servoventilation (ASV) is now an option, but no large series exist describing the application and effectiveness of ASV. METHODS: Retrospective chart review of the first 100 patients who underwent polysomnography using ASV at Mayo Clinic Sleep Center. RESULTS: ASV titration was performed for CompSAS (63%), CSA (22%), or CSA/Cheyne Stokes breathing patterns (15%). The median diagnostic sleep apnea hypopnea index (AHI) was 48 events per hour (range, 24 to 62). With CPAP, obstructive apneas decreased, but the appearance of central apneas maintained the AHI at 31 events per hour (range, 17 to 47) [p = 0.02]. With bilevel positive airway pressure (BPAP) in spontaneous mode, AHI trended toward worsening vs baseline, with a median of 75 events per hour (range, 46 to 111) [p = 0.055]. BPAP with a backup rate improved the AHI to 15 events per hour (range, 11 to 31) [p = 0.002]. Use of ASV dramatically improved the AHI to a mean of 5 events per hour (range, 1 to 11) vs baseline and vs CPAP (p < 0.0001). ASV also resulted in an increase in rapid eye movement sleep vs baseline and CPAP (18% vs 12% and 10%, respectively; p < 0.0001). Overall, 64 patients responded to the ASV treatment with a mean AHI < 10 events per hour. Of the 44 successful survey follow-up patients contacted, 32 patients reported some improvement in sleep quality. CONCLUSION: The ASV device appears to be an effective treatment of both CompSAS and CSA syndromes that are resistant to CPAP.

Gali B, Whalen FX, Gay PC, Olson EJ, Schroeder DR, Plevak DJ, Morgenthaler TI. · Department of Anesthesiology, Mayo Clinic, Rochester, MN 55905, USA. · J Clin Sleep Med. · Pubmed #17993039 links to  free full text

Abstract: STUDY OBJECTIVES: Obstructive sleep apnea (OSA) has been associated with increased perioperative morbidity and mortality. We initiated a protocol designed to screen patients preoperatively and monitor them postoperatively. The goal was to identify patients who were at risk for oxygen desaturation after discharge from the postanesthesia recovery room (PACU). METHODS: Patients without previously diagnosed OSA presenting to the preoperative evaluation clinic were assessed over a 10.5-month period using a validated prediction rule to identify patients thought to be at high risk of OSA (sleep apnea clinical score, SACS > or = 15). Following surgery, patients were monitored in the PACU for significant respiratory events: apnea, increased FiO2 requirement, pain-sedation mismatch, or episodes of desaturation. Patients were placed in 3 groups based on their SACS and the presence or absence of recurrent PACU respiratory events (group 1: SACS < 15, no recurrent events; group 2: SACS > or =15, no recurrent events; and group 3: SACS > or = 15, recurrent events.) The number of oxygen desaturations > or = 4% per hour, the oxygen desaturation index (ODI), was calculated for each patient for 24 to 48 hours after PACU discharge. An ODI > 10 was the threshold chosen to indicate a high frequency of oxygen desaturation. RESULTS: The percentage of patients with ODI > 10 differed significantly across the 3 study groups (12%, 37%, and 57%, for groups 1-3, p = 0.005). Mean ODI in group 1 was significantly different from groups 2 and 3 (5.8 compared to 10.0 group 2 and 11.4 group 3 with p = 0.001). CONCLUSIONS: We have shown that combining preoperative screening is useful for identifying patients at risk for oxygen desaturation after PACU discharge.

Ramar K, Olson EJ, Morgenthaler TI. · Mayo Clinic Sleep Disorders Center, Division of Pulmonary and Critical Care Medicine, Rochester, MN 55905, USA. · Sleep Med. · Pubmed #17923436 No free full text.

This publication has no abstract.

Cassar A, Morgenthaler TI, Lennon RJ, Rihal CS, Lerman A. · Department of Internal Medicine, Mayo College of Medicine, Rochester, Minnesota 55902, USA. · J Am Coll Cardiol. · Pubmed #17903628 No free full text.

Abstract: OBJECTIVES: Our purpose was to compare outcomes of patients treated for obstructive sleep apnea (OSA) versus patients with untreated OSA, all of whom had undergone percutaneous coronary intervention (PCI). BACKGROUND: Obstructive sleep apnea has been associated with increases in fatal and nonfatal cardiovascular events. It is not known whether treatment of OSA in patients who have had PCI results in a better outcome. METHODS: In a retrospective cohort study, a group of patients with OSA diagnosed with polysomnography between 1992 and 2004 (apnea-hypopnea index > or =15) who subsequently underwent a PCI (n = 371) were stratified according to whether they were treated for OSA (n = 175) or not (n = 196). Main outcome measures were cardiac death, general mortality, major adverse cardiac events (MACE) (severe angina, myocardial infarction, PCI, coronary artery bypass grafting, or death), and major adverse cardiac or cerebrovascular events (MACCE). RESULTS: Patients treated for OSA had a statistically significant decreased number of cardiac deaths on follow-up when compared with untreated OSA patients (3% [95% confidence interval (CI) 0% to 6%] vs. 10% [95% CI 5% to 14%] after 5 years, p = 0.027), as well as a trend toward decreased all-cause mortality (p = 0.058). There was no difference in the number of MACE or MACCE between the 2 groups (p = 0.91 and 0.96, respectively). CONCLUSIONS: Treatment of OSA is associated with a reduction in the number of cardiac deaths, but not in MACE or MACCE, after PCI. Screening for and treating OSA in patients with coronary artery disease who may undergo PCI may result in decreased cardiac death.

Kuzniar TJ, Pusalavidyasagar S, Gay PC, Morgenthaler TI. · Division of Pulmonary and Critical Care, Evanston Northwestern Healthcare, Evanston, IL, USA. · Sleep Breath. · Pubmed #17874254 No free full text.

Abstract: Patients with complex sleep apnea syndrome (CompSAS) have obstructive sleep apnea but develop troublesome central sleep apnea activity or Cheyne-Stokes breathing when provided continuous positive airway pressure (CPAP) therapy. We examined whether CompSAS activity persists with long-term CPAP treatment. We retrospectively identified all patients with CompSAS who underwent two therapeutic polysomnograms (PSGs) separated by at least 1 month during 2003-2005. We compared PSG findings between the initial and follow-up study and noted clinical responses to therapy. We identified 13 CompSAS patients meeting criteria. Most follow-up PSGs were ordered after an abnormal overnight oximetry on CPAP or because of CPAP intolerance after 195 (49-562) days. The residual apnea-hypopnea index (AHI) on CPAP decreased from 26 (23-40) on the first PSG to 7 (3-21.5) on the follow-up PSG. Only seven patients reached AHI < 10 and 6 had AHI > or = 10 ("CPAP nonresponders") at follow-up. "CPAP nonresponders" were sleepier (Epworth Sleepiness Score 13 [12.5-14] vs 9 [6-9.5], p = 0.03) and trended toward lower body mass index (29.7 [28.6-31.6] vs 34.3 [32.5-35.1], p = 0.06). Both groups were equally compliant with CPAP therapy. Although the AHI tends to improve over time in CompSAS patients treated with CPAP, in this retrospective study nearly half-maintained a persistently elevated AHI. A prospective trial is merited to determine the optimal treatment for these patients.

Morgenthaler TI, Olson EJ, Gay P, Decker PA, Herold D, Moore W, Silber MH, Krahn L. · Mayo Clinic Sleep Disorders Center, 200 First Street SW, Rochester, MN 55905, USA. · J Clin Sleep Med. · Pubmed #17557437 No free full text.

Abstract: STUDY OBJECTIVES: We sought to evaluate whether a targeted obstructive sleep apnea (OSA) consult (TOSAC) protocol that reduced sleep-specialist time spent with patients suspected of having OSA would improve quality of care compared with the previous clinical method for evaluation of patients internally referred for suspected OSA. METHODS: Prospective cohort design. TOSAC patients received oximetry and criteria screening prior to a split-night polysomnography and a 45-minute sleep-specialist consult, while control patients received consult, testing, and a follow-up visit (90 minutes of sleep-specialist time). RESULTS: We enrolled 186 TOSAC and 94 control patients. TOSAC patients completed their evaluation in a median of 7.0 days compared with 60.0 days for the controls (p < .001). At baseline, the TOSAC group was sleepier (Epworth Sleepiness Scale 13.9+/-4.5 vs 11.0+/-4.3; p < .001) and had a slightly lower quality of life (Functional Outcomes of Sleep Questionnaire 15.0+/-3.0 vs 16.8+/-2.2, p < .001) than controls. The apnea-hypopnea index noted at polysomnography was similar in TOSAC and control patients (28.6+/-29.5 vs 23.1+/-23.9, p = .156), and the prevalence of OSA was similar in both groups (75% vs 72%, p = .616). At 1 month of therapy, improvement in the Epworth Sleepiness Scale and overall patient satisfaction were similar between groups (all p > .10), while TOSAC patients had a slightly greater improvement on the Functional Outcomes of Sleep Questionnaire (p = .010). TOSAC patients reported better subjective continuous positive airway pressure compliance (median 42.0 vs 32.5 hours/week; p = .037). CONCLUSIONS: A protocol-driven evaluation pathway for OSA that used screening with oximetry and less sleep-specialist time shortened access and produced similar diagnoses, improvements in sleepiness and quality of life, and overall satisfaction.

Morgenthaler TI, Gay PC, Gordon N, Brown LK. · Mayo Clinic Sleep Disorders Center, 200 First Street SW, Rochester, MN 55905, USA. · Sleep. · Pubmed #17520791 No free full text.

Abstract: RATIONALE: Although continuous positive airway pressure (CPAP) is most often effective in patients with obstructive sleep apnea, optimal treatment of patients with predominantly mixed apneas, central sleep apnea syndrome/Cheyne-Stokes respiration (CSA/CSR), or complex sleep apnea (CompSAS) is less straightforward, and may require alternative ventilatory assist modalities. OBJECTIVES: To compare the efficacy of noninvasive positive pressure ventilation (NPPV) with adaptive servoventilation (ASV) in treating patients with centrally mediated breathing abnormalities. We hypothesized that NPPV and ASV would be equivalently efficacious in improving the apnea/hypopnea index (AHI) and respiratory arousal index (RAI). METHODS: Prospective randomized crossover clinical trial comparing NPPV with ASV in patients with CSA/CSR, predominantly mixed apneas, and CompSAS in an acute setting. MEASUREMENTS AND MAIN RESULTS: 21 patients (6 with CSA/CSR, 6 with predominantly mixed apneas, and 9 with CompSAS) with initial diagnostic AHI +/- standard deviation 51.9 +/- 22.8/hr and RAI 45.5 < or = 26.5/hr completed the study. Following optimal titration with CPAP (N = 15), disturbed breathing and disturbed sleep remained high with mean AHI = 34.3 +/- 25.7 and RAI = 32.1 +/- 29.7. AHI and RAI were markedly reduced with both NPPV (6.2 +/- 7.6 and 6.4 +/- 8.2) and ASV (0.8 +/- 2.4 and 2.4 +/- 4.5). Treatment AHI and RAI were both significantly lower using ASV (P < 0.01). CONCLUSION: These data confirm that in patients with CSA/CSR, mixed apneas, and CompSAS, both NPPV and ASV are effective in normalizing breathing and sleep parameters, and that ASV does so more effectively than NPPV in these types of patients.

Morgenthaler TI, Kagramanov V, Hanak V, Decker PA. · Mayo Clinic Sleep Disorders Center, Division of Pulmonary and Critical Care Medicine, 200 First Street SW, Rochester, MN 55905, USA. · Sleep. · Pubmed #17040008 No free full text.

Abstract: STUDY OBJECTIVES: Some patients with apparent obstructive sleep apnea hypopnea syndrome (OSAHS) have elimination of obstructive events but emergence of problematic central apneas or Cheyne-Stokes breathing pattern. Patients with this sleep-disordered breathing problem, which for the sake of study we call the "complex sleep apnea syndrome," are not well characterized. We sought to determine the prevalence of complex sleep apnea syndrome and hypothesized that the clinical characteristics of patients with complex sleep apnea syndrome would more nearly resemble those of patients with central sleep apnea syndrome (CSA) than with those of patients with OSAHS. DESIGN: Retrospective review SETTING: Sleep disorders center. PATIENTS OR PARTICIPANTS: Two hundred twenty-three adults consecutively referred over 1 month plus 20 consecutive patients diagnosed with CSA. INTERVENTIONS: NA. MEASUREMENTS AND RESULTS: Prevalence of complex sleep apnea syndrome, OSAHS, and CSA in the 1-month sample was 15%, 84%, and 0.4%, respectively. Patients with complex sleep apnea syndrome differed in gender from patients with OSAHS (81% vs 60% men, p < .05) but were otherwise similar in sleep and cardiovascular history. Patients with complex sleep apnea syndrome had fewer maintenance-insomnia complaints (32% vs 79%; p < .05) than patients with CSA but were otherwise not significantly different clinically. Diagnostic apnea-hypopnea index for patients with complex sleep apnea syndrome, OSAHS, and CSA was 32.3 +/- 26.8, 20.6 +/- 23.7, and 38.3 +/- 36.2, respectively (p = .005). Continuous positive airway pressure suppressed obstructive breathing, but residual apnea-hypopnea index, mostly from central apneas, remained high in patients with complex sleep apnea syndrome and CSA (21.7 +/- 18.6 in complex sleep apnea syndrome, 32.9 +/- 30.8 in CSA vs 2.14 +/- 3.14 in OSAHS; p < .001). CONCLUSIONS: Patients with complex sleep apnea syndrome are mostly similar to those with OSAHS until one applies continuous positive airway pressure. They are left with very disrupted breathing and sleep on continuous positive airway pressure. Clinical risk factors don't predict the emergence of complex sleep apnea syndrome, and best treatment is not known.

Pusalavidyasagar SS, Olson EJ, Gay PC, Morgenthaler TI. · Division of Cardiovascular Research, Mayo Clinic, Rochester, USA. · Sleep Med. · Pubmed #16931153 No free full text.

Abstract: BACKGROUND AND PURPOSE: Some patients with obstructive sleep apnea syndrome (OSAS) develop problematic central apneas or Cheyne-Stokes pattern with acute application of continuous positive airway pressure (CPAP), herein called complex sleep apnea syndrome (CompSAS). This response makes it difficult to be certain that CPAP will be a successful treatment strategy. We sought to compare treatments between patients with CompSAS vs. OSAS and hypothesized that CompSAS patients would find CPAP less effective and have more problems with adherence than patients with OSAS. PATIENTS AND METHODS: We performed a retrospective review of patients studied in our sleep disorders center over 1 month. RESULTS: There were 133 patients with OSAS (mean age=57.6+/-12.2 years; males=63.9%) and 34 with CompSAS (mean age=54.4+/-16 years; males=82.35%). CPAP was prescribed in 93.7 and 87.9% of OSAS and CompSAS patients, respectively (P=0.284), with no significant difference in required CPAP pressures (P=0.112). There was no difference in prescription frequency of alternative therapies. Mean time to the first follow-up was shorter in CompSAS patients (46.2+/-47.3 vs. 53.8+/-36.8 days; P=0.022). CPAP compliance in OSAS and CompSAS patients (5.1+/-1.6 vs. 6.1+/-1.5h, P=0.156) and improvement in Epworth Sleepiness Scale (ESS) (-4.6+/-4.8 vs. -5.9+/-6.9, P=0.483) was similar. However, interface problems were more common in CompSAS patients, especially air hunger/dyspnea (0.8 vs. 8.8%) and inadvertent mask removal (2.6 vs. 17.7%) (all P<0.050). CONCLUSION: CompSAS patients have more CPAP interface problems and require more follow-up than OSAS patients but with intervention may have similar treatment results compared to patients with OSAS.

Martinez MW, Rodysill KJ, Morgenthaler TI. · Department of Internal Medicine, Mayo Clinic College of Medicine, Rochester, Minn 55905, USA. · Mayo Clin Proc. · Pubmed #15819281 links to  free full text

Abstract: OBJECTIVE: To examine how clinical factors and results from ambulatory overnight oximetry related to recommendations for further sleep evaluation in patients with clinically suspected obstructive sleep apnea syndrome. PATIENTS AND METHODS: We reviewed 100 medical records selected randomly from 375 consecutive patients for whom ambulatory overnight oximetry had been ordered by internists and completed between September 1, 2001, and May 1, 2002. We analyzed relationships among clinical Information, oximetry results, resultant recommendations, and patient follow-up data. RESULTS: Only 21 of 100 patients had normal results from ambulatory overnight oximetry; 5 were referred for further sleep consultation. Abnormal results from ambulatory overnight oximetry were seen in 79 patients, but only 51 were referred for further sleep evaluation. Abnormal results from ambulatory overnight oximetry were associated with only a small increased likelihood of referral (likelihood ratio, 2.7; confidence interval, 1.2-6.0). Those with an oxygen desaturation index (number of desaturation events per hour of recording time) of greater than 15 received sleep consultation at a median of 8 days after completion of oximetry, whereas those with an oxygen desaturation index of 6 to 10 were evaluated in a median of 42 days (P=.60). All 17 patients who had minimum oxygen saturation of less than 80% were referred for further evaluation. CONCLUSIONS: Abnormal results from ambulatory overnight oximetry per se may not substantially influence internist referral of patients with clinically suspected sleep apnea for further sleep evaluation. Rather, severity of oximetry abnormalities is used along with other patient-related factors and sleep study accessibility to prioritize the need and urgency of further evaluation.