Sleep nasendoscopy: a 10-year retrospective audit study

Drug-induced sleep endoscopy in sleep-disordered breathing: report on 1,249 cases

OBJECTIVES/HYPOTHESIS

To describe upper airway (UA) collapse patterns during drug-induced sleep endoscopy (DISE) in a large cohort of patients with sleep-disordered breathing (SDB) and to assess associations with anthropometric and polysomnographic parameters.

STUDY DESIGN

Observational study.

METHODS

A total of 1,249 patients [age 47 ± 10 y; apnea-hypopnea index (AHI) 18.9 ± 15.3/h; body mass index (BMI) 27.2 ± 3.7 kg/m(2)] underwent polysomnography and DISE. DISE findings were categorized to the following UA levels: palate, oropharynx, tongue base, and hypopharynx. The degree of collapse was reported as complete, partial, or none. The pattern of the obstruction was described as anteroposterior, lateral, or concentric. Associations between DISE findings and anthropometric and polysomnographic parameters were analyzed.

RESULTS

Palatal collapse was seen most frequently (81%). Multilevel collapse was noted in 68.2% of all patients. The most frequently observed multilevel collapse pattern was a combination of palatal and tongue base collapse (25.5%). Palatal collapse was seen most frequently (81%). The prevalence of complete collapse, multilevel collapse, and hypopharyngeal collapse increased with increasing severity of obstructive sleep apnea (OSA). Multilevel and complete collapse were more prevalent in obese patients and in those with more severe OSA. Both higher BMI and AHI values were associated with a higher probability of complete concentric palatal collapse.

CONCLUSION

The current study provides an overview of UA collapse patterns in a large cohort of SDB patients who underwent DISE. The associations found in this study may indicate that UA collapse patterns observed during DISE cannot be fully explained by selected baseline polysomnographic and anthropometric characteristics.

[Drug-induced sleep videoendoscopy: clinical usefulness and literature review]

Fiberoptic examination of the pharynx under drug-induced sleep is a test that helps to detect the areas of vibration and collapse in patients with sleep-disordered breathing. This article is a review of the available literature on the subject, aimed at helping otolaryngologists to understand the procedure and to resolve some controversies surrounding it.

Change of obstruction level during drug-induced sleep endoscopy according to sedation depth in obstructive sleep apnea

OBJECTIVES/HYPOTHESIS

We evaluated the change in upper airway collapse according to the depth of sedation during drug-induced sleep endoscopy (DISE), as well as characteristics possibly associated with that change.

STUDY DESIGN

Prospective, single center, observational study.

METHODS

Twenty-nine patients with upper airway collapse were twice evaluated using DISE according to the depth of sedation, as confirmed by the bispectral index (BIS), which is a measure of the level of consciousness. Changes in the site and degree of obstruction according to the change in sedation depth at the retropalatal and the retroglossal levels were evaluated. The possible contributing factors of this change were explored.

RESULTS

As DISE sedation deepened, the upper airway became narrower in 37% of patients at the retropalatal level and in 44.8% of patients at the retroglossal level. No clinical, polysomnographic, or cephalometric variables showed any association with the change in the degree of retroglossal airway narrowing, with the exception of mouth breathing during DISE.

CONCLUSIONS

The degree of upper airway narrowing can be aggravated according to the sedation depth. The monitoring of sedation depth during DISE is critical, especially in patients with mouth breathing.

A comparison of the Fujita classification of awake and drug-induced sleep endoscopy patients

Only a few studies have compared the outcomes of patients kept awake during endoscopic examination and subjects submitted to drug-induced sleep endoscopy.

OBJECTIVE

This study aimed to compare the endoscopic findings of patients submitted to outpatient endoscopy and endoscopic examination with sedation by propofol based on the Fujita Classification.

METHOD

This cross-sectional cohort study enrolled 34 patients. The subjects underwent ENT examination, nasal endoscopy with Müller's maneuver, and drug-induced sleep endoscopy with propofol. The Fujita Classification was used to compare the two modes of endoscopic examination. The examinations were correlated to patient clinical data such as BMI, age, and OSAS severity.

RESULTS

There was no agreement between the two modes of endoscopic examination, whether for the group in general or for the analyzed subgroups.

CONCLUSION

There was no agreement between the endoscopic findings of endoscopic examinations done with the patient awake or in drug-induced sleep.

Polysomnographic evaluation of propofol-induced sleep in patients with respiratory sleep disorders and controls

OBJECTIVES/HYPOTHESIS

The treatment for obstructive sleep apnea syndrome (OSAS) depends on correct localization of upper airway obstruction, exception made for continuous positive airway pressure (CPAP). Drug-induced sleep endoscopy (DISE) with propofol allows this evaluation, but the drug effects on sleep parameters are not yet well established. Our objective was to study by polysomnography (PSG) whether propofol would change sleep parameters by means of a prospective cross-sectional clinical study in a tertiary hospital.

STUDY DESIGN

Thirty non-obese subjects (6 controls and 24 OSAS patients) underwent two daytime PSGs, one with DISE and the other without DISE.

METHODS

During DISE exam, propofol was administered intravenously in continuous infusion using a target-controlled infusion pump. The parameters evaluated were: presence of snoring, apnea-hypopnea index (AHI), oxyhemoglobin saturation (SaO2), and sleep macroarchitecture.

RESULTS

Snoring was absent in all healthy subjects during DISE sleep with propofol, and present in all OSAS patients (100%). AHI and mean SaO2 showed no statistical difference between the two tests, with and without propofol. However, minimum SaO2 was significantly lower during propofol infusion (88.64 for without vs. 85.04 for with propofol; P < 0.01). Regarding sleep macroarchitecture, the tests with propofol significantly increased N3 sleep and totally extinguished REM sleep (P < 0.005).

CONCLUSIONS

The results demonstrate that propofol significantly changes sleep macroarchitecture. However, the main respiratory parameters, AHI and mean SaO2 , remained unaffected. Thus, in order to determine the sites of obstruction, propofol DISE used with target-controlled infusion proved to be an effective drug for endoscopic evaluation of patients with OSAS.

Tongue suspension: an evidence-based review and comparison to hypopharyngeal surgery for OSA

OBJECTIVES/HYPOTHESIS

Our first objective was to perform a systematic review of suture-based tongue suspension procedures as a stand-alone therapy for hypopharyngeal obstruction in obstructive sleep apnea (OSA). A second objective compared outcomes of tongue suspension as part of a multilevel approach to OSA surgery to genioglossus advancement (GA) with uvulopalatopharyngoplasty (UPPP), and to genioglossus advancement with hyoid suspension (GAHM) with UPPP.

STUDY DESIGN

Systematic review.

METHODS

The PubMed database was queried for English-language studies published after 1997 to create four cohorts: tongue suspension alone, tongue suspension with UPPP, GA + UPPP, and GAHM with UPPP. Chi-squared test was used to compare outcomes between cohorts.

RESULTS

Twenty-seven studies were included, broken down into cohorts based on our selection criteria. Six studies qualified for the tongue suspension-alone group with a surgical success rate of 36.6%. Eight studies qualified for our cohort of tongue suspension with UPPP with a surgical success rate of 62.3%. Eighteen studies qualified for our remaining two cohorts: GA + UPPP, and GAHM + UPPP. Their surgical success rates were both 61.1%. A chi-squared test to compare surgical outcomes showed that there was no difference between tongue suspension with UPPP, GA + UPPP, and GAHM + UPPP.

CONCLUSION

Tongue suspension is effective and safe as part of a multilevel surgical approach for patients with OSA. As a stand-alone procedure, its success rate is 36.6%, comparable to UPPP procedures for OSA success rates across the board. Tongue suspension should be considered in patients with OSA who demonstrate tongue base obstruction.

Drug-induced sleep endoscopy: a two drug comparison and simultaneous polysomnography

The purpose of the present study was to compare pharyngeal and polysomnographical findings during drug-induced sleep endoscopy (DISE) performed with either propofol or midazolam as a single sedative agent. It is prospective, non-randomized, double-blinded case series study. Sixteen patients with sleep disordered breathing were sedated first with propofol and after full wake up with midazolam. Simultaneous polysomnography (PSG) was performed. We compared the zones of obstruction and vibration found with both drugs using the VOTE classification. Simultaneous PSG findings are also compared. There were 15 men and one woman; the mean age was 42.7 years old, mean body mass index 26.9 kg/m(2). Average DISE duration was 20 min with Propofol and 14.3 min with Midazolam. The induced sleep stage obtained was N2 with both drugs. Outpatient physical exam did not correlate with drug-induced sleep findings. There was a good correlation between DISE results with both drugs in all the areas of collapse except the velum (p < 0.005). Using a continuous perfusion, there is a good agreement in the findings observed in DISE performed with propofol and midazolam and PSG.

Sleep-related adductor laryngeal dystonia causing sleep apnea: a sleep-related breathing disorder diagnosed with sleep endoscopy and treated with botulinum toxin

OBJECTIVES/HYPOTHESIS

Obstructive sleep apnea syndrome (OSAS) is a chronic condition, characterized by recurrent episodes of upper airway collapse during sleep, which affects up to 5% of adults in the Western population. The muscle tone of the human body ordinarily relaxes during sleep, thus causing airway obstruction and leading to sleep apnea. We report a case of a 68-years old male in which dystonic closure of the larynx during sleep caused OSAS. The sleep endoscopy was crucial in establishing the diagnosis of laryngeal dystonia. A botulinum toxin injection in the vocal cord improved the OSAS. These findings define a novel sleep-related breathing disorder.

Evaluation of upper airway obstruction in snoring patients using digital video stroboscopy

Stroboscopy is routinely used in voice disorder clinics but its use in studying the mechanisms of upper airway obstruction in patients who snore has not yet been described. This study combines the use of stroboscopy during sleep nasendoscopy to evaluate the oscillations and vibrations observed during snoring in slow motion. In addition, we utilised the multi-dimensional voice programme simultaneously to study some of the acoustic parameters of snoring whilst visualising the dynamics of the upper airway. Forty-five patients with primary snoring or mild obstructive sleep apnoea were recruited at two different centres and underwent sleep nasendoscopy. The simultaneous use of acoustic analysis was included to ascertain whether sound analysis alone could replace the need for using the sedation endoscopy in these patients. The use of a stroboscopic light source indeed enhanced the visualisation during the procedure and some subtle aspects of the mechanisms of upper airway obstruction, such as vibrations of the posterior pharyngeal wall and mucosal waves were identified. Most of the patients in this study exhibited multilevel obstruction and thus acoustic analysis alone would not be sufficient in accurately locating the site of upper airway obstruction in snorers.

Sleep endoscopy with midazolam: sedation level evaluation with bispectral analysis

OBJECTIVE

This study examines subjects' level of consciousness with bispectral analysis in sedation endoscopy of the upper airway.

STUDY DESIGN

A prospective study.

SETTING

University hospital.

SUBJECTS AND METHODS

Bispectral analysis levels recorded in natural sleep of 43 patients with obstructive sleep apnea during an overnight polysomnographic sleep study were directly compared with the levels recorded during midazolam sedation sleep endoscopy in the same subjects. The possible muscle relaxation effect of midazolam was examined via surface chin electrodes. Supine Müller maneuver findings in 50 patients with obstructive sleep apnea were also compared with soft tissue dynamics during midazolam sedation sleep endoscopy.

RESULTS

In our study of the 43 patients with bispectral analysis during natural sleep and midazolam sedation sleep endoscopy, a predominance of bispectral analysis values indicating N1 and N2 sleep was observed during the sedation study. Midazolam failed to achieve deeper levels of sleep with minimal N3 and no convincing rapid eye movement. As N1 and N2 are the stages during which maximal dynamic activities occur, and they make up an average of 70.5% of total sleep time, from 210 sleep studies at our laboratory, the present technique would be ideal as a surgical assessment tool. No muscle relaxation effect could be detected at our protocol dose of midazolam. The supine Müller maneuver findings were significantly different from those observed during sedation sleep.

CONCLUSION

These findings support the value of sleep endoscopy as an efficient and informative technique for the examination of upper airway dynamics relevant to focused surgical planning.

A trial of drug-induced sleep endoscopy in the surgical management of sleep-disordered breathing

OBJECTIVES/HYPOTHESIS

To determine the reliability and validity of drug-induced sleep endoscopy (DISE) for patients undergoing surgery for sleep-disordered breathing (SDB).

STUDY DESIGN

Non-randomized, prospective clinical trial.

METHODS

Patients with sleep-disordered breathing were evaluated for multi-level upper airway surgery by awake and drug-induced sleep endoscopy to identify levels and degree of airway collapse. The reliability of a drug-induced sleep endoscopy rating index was assessed by comparing scores of three blinded investigators. The validity was assessed by comparison of drug-induced sleep endoscopy index scores from awake and drug-induced sleep endoscopy; correlation between drug-induced sleep endoscopy scores and Apnea-Hypopnea Index; and determination whether drug-induced sleep endoscopy affected the original surgical plan.

RESULTS

Thirty-eight patients (22 M, 16 F) underwent preoperative assessment with awake and drug-induced sleep endoscopy. Drug-induced sleep endoscopy was successfully performed in all but one patient (97%) who became combative during propofol infusion. Using an internal airway grading scale, drug-induced sleep endoscopy demonstrated more severity of collapse than awake endoscopy (P = 0.0001). The surgical plan was changed after drug-induced sleep endoscopy in 23 (62%) cases and unchanged in 14 (38%). The majority (73%) had multi-segmental airway collapse with fewer having single-level palatal (16%) or tongue base (11%) collapse. Scoring of drug-induced sleep endoscopy videos demonstrated good intrarater (κ 0.61) and interrater (κ 0.65) correlation.

CONCLUSIONS

Drug-induced sleep endoscopy provides more clinical information to assess airway function and collapse than awake endoscopy alone and assists in the surgical planning. Additional investigation is needed to standardize drug-induced sleep endoscopy techniques, training, and interpretation.

Validation of sleep nasendoscopy for assessment of snoring with bispectral index monitoring

Bispectral index (BIS) monitor is a neurophysiological monitoring device which continually analyses a patient's electroencephalogram during sedation and general anaesthesia to assess the level of consciousness and depth of anaesthesia. BIS monitoring, whilst performing sleep nasendoscopy (using midazolam and propofol), has helped validate depth of sedation and allowed comparison with levels of sedation of control patients during natural sleep. A prospective study of 30 patients with snoring undergoing sleep nasendoscopy with BIS monitoring was conducted. BIS monitoring was recorded throughout the procedure and assessment of snoring was made at the appropriate level of sedation and snoring. BIS values were compared with control patients. The 30 patients undergoing sleep nasendoscopy had average BIS values ranging from 50.72 to 61.2. Similar results were seen with BIS and oxygen saturation in the control group. BIS monitoring provides an adjunct to the assessment of sleep nasendoscopy in determining the level of sedation required for snoring assessment. Comparable BIS values and oxygen saturation levels were obtained between controls and patients during sedation-induced sleep, thus validating the role of sleep nasendoscopy.

Nonresponders to pharyngeal surgery for obstructive sleep apnea: insights from drug-induced sleep endoscopy

OBJECTIVES/HYPOTHESIS

To examine drug-induced sleep endoscopy (DISE) findings in nonresponders to previous pharyngeal obstructive sleep apnea (OSA) surgery.

STUDY DESIGN

Cross-sectional.

METHODS

DISE using propofol for unconscious sedation was performed in nonresponders to previous OSA surgery (including palate surgery with or without tonsillectomy and possible other procedures). Nonresponders were defined as subjects with a postoperative apnea-hypopnea index more than 10 events/hr. Recorded findings from DISE included the presence and degree of obstruction in the palatal and hypopharyngeal regions, the contributions of specific structures (velum, oropharyngeal lateral walls, tongue, and/or epiglottis) to upper airway obstruction, and the degree of mouth opening.

RESULTS

Thirty-three nonresponders underwent DISE examinations. Age was 46.2 ± 11.8 years, and 9% (3 of 33) were female. On diagnostic sleep studies prior to DISE, the apnea-hypopnea index was 43.4 ± 26.6 events/hr. During DISE, a majority of subjects demonstrated residual palatal obstruction, and almost all demonstrated hypopharyngeal obstruction. A diversity of individual structures contributed to upper airway obstruction, often in combination. Moderate to severe mouth opening occurred in one-third of subjects and was associated with narrowing of upper airway dimensions.

CONCLUSIONS

Residual upper airway obstruction in surgery nonresponders likely occurs due to multiple mechanisms, and DISE may enhance the understanding of them.

The role of the nose in snoring and obstructive sleep apnoea: an update

Multilevel anatomic obstruction is often present in snoring and obstructive sleep apnoea (OSA). As the nose is the first anatomical boundary of the upper airway, nasal obstruction may contribute to sleep-disordered breathing (SDB). A number of pathophysiological mechanisms can potentially explain the role of nasal pathology in SDB. These include the Starling resistor model, the unstable oral airway, the nasal ventilatory reflex and the role of nitric oxide (NO). Clinically, a number of case–control studies have shown that nasal obstruction is associated with snoring and mild SDB. However, there is not a linear correlation between the degree of nasal obstruction and the severity of SDB, while nasal obstruction is not the main contributing factor in the majority of patients with moderate to severe OSA. Randomised controlled studies have shown that in patients with allergic rhinitis or non-allergic rhinitis and sleep disturbance, nasal steroids could improve the subjective quality of sleep, and may be useful for patients with mild OSA, however, they are not by themselves an adequate treatment for most OSA patients. Similarly, nasal surgery may improve quality of life and snoring in a subgroup of patients with mild SDB and septal deviation, but it is not an effective treatment for OSA as such. On the other hand, in patients who do not tolerate continuous positive airway pressure (CPAP) well, if upper airway evaluation demonstrates an obstructive nasal passage, nasal airway surgery can improve CPAP compliance and adherence.

Assessment of obstruction level and selection of patients for obstructive sleep apnoea surgery: an evidence-based approach

Introduction:

Obstructive sleep apnoea has long been recognised as a clinical syndrome; however, high quality evidence on the effects of surgery for this condition is still missing. Despite this, a consensus seems to be evolving, albeit based on limited evidence, that surgery should be offered as a second line treatment to suitable patients with obstructive sleep apnoea.

Aims:

This article aims to assess the different methods of investigating upper airway obstruction in patients with obstructive sleep apnoea, in respect to these methods' relevance to surgical treatment, via a systematic review of the literature.

Methods:

The Cochrane Controlled Trials Register, Medline and EMBASE were searched from 1966 onwards. The search was performed in August 2008. A total of 2001 citations were retrieved.

Results and conclusion:

There is not yet a generally accepted way to assess surgical candidacy based on the level of obstruction. Better organised clinical studies with well defined endpoints are needed. In the meanwhile, it appears that sleep nasendoscopy, acoustic reflectometry and pressure catheters can all provide useful information, and their use may be decided upon based on the experience and resources available in individual departments.

Is sleep nasendoscopy a valuable adjunct to clinical examination in the evaluation of upper airway obstruction?

The objective of the study is to assess the correlation between outpatient department (OPD) assessment and sleep nasendoscopy (SNE) in treatment planning for sleep related breathing disorders. The study design includes a blinded, cohort study comparing the treatment prediction based on OPD clinical evaluation with SNE in consecutive, adult patients by a single clinician with a specialist interest in snoring related disorders. Patients with moderate to severe obstructive sleep apnoea and those who had undergone previous treatment were excluded. The study was conducted in Royal National Throat, Nose and Ear Hospital, London and Queen's Hospital, Romford. Ninety-four patients were recruited as participants for the study. The main outcome measures include site of obstruction and treatment planning. The results show no significant correlation between the two groups with SNE recommending less surgical intervention and a choice of surgical and non-surgical management in greater number of patients. In conclusion, even in experienced hands, clinical prediction is significantly modified by SNE findings. The addition of SNE to the diagnostic pathway, to assess the three-dimensional dynamic anatomy of the upper airway, provides a valuable adjunct to the OPD assessment of upper airway collapse. This affords the clinician a greater accuracy of diagnosis and the patient a more focussed management strategy with increased choice of modality of treatment.