Can drug-induced sleep endoscopy (DISE) predict compliance with positive airway pressure therapy? A pilot study.

PURPOSE: Drug-induced sleep endoscopy (DISE) has been poorly explored as an examination to assess positive airway pressure (PAP) therapy in patients with obstructive sleep apnea (OSA). The present study aimed to identify by DISE possible characteristics related to low compliance with PAP therapy due to respiratory complaints. METHODS: Patients using PAP for OSA underwent DISE in two conditions: (1) baseline (without PAP) and (2) PAP (with the same mask and airway pressure used at home). We compared patients reporting low compliance to PAP due to respiratory complaints to those well-adapted to therapy. VOTE classification (assessment of velopharynx, oropharynx, tongue base, and epiglottis) and TOTAL VOTE score (the sum of VOTE scores at each anatomical site) were assessed. ROC curve analyzed the accuracy of TOTAL VOTE to predict low compliance due to persistent pharyngeal obstruction in both conditions. RESULTS: Of 19 patients enrolled, all presented multilevel pharyngeal obstruction at baseline condition, with no difference between groups at this study point. When PAP was added, the median VOTE value was higher in the epiglottis (P value=0.02) and tended to be higher at the velum and tongue base in the poorly adapted group; TOTAL VOTE score was also significantly increased in patients with low compliance (P value<0.001). ROC curve demonstrated that patients with TOTAL VOTE scored 2.5 or more during DISE with PAP presented a 4.6-fold higher risk for low compliance with PAP therapy due to pharyngeal obstruction (AUC: 0.88±0.07; P value<0.01; sensitivity: 77%; specificity: 83%). CONCLUSIONS: Adding PAP during a DISE examination may help to predict persistent pharyngeal obstruction during PAP therapy.

Correlation between the transverse dimension of the maxilla, upper airway obstructive site, and OSA severity.

STUDY OBJECTIVES: Acquiring a better comprehension of obstructive sleep apnea physiopathology can contribute to improving patient selection for surgical treatments. We hypothesize that maxillary transverse deficiency restricts the space available for the tongue, leading to upper airway obstruction during sleep. Our primary hypothesis was that maxillary transverse deficiency increases the prevalence of tongue collapse during drug-induced sleep endoscopy (DISE). The secondary hypothesis was that maxillary transverse deficiency will also increase the prevalence of circumferential collapse at the velopharynx. The exploratory hypothesis was that maxillary transverse deficiency is associated with increased obstructive sleep apnea severity. The objectives of this study were to correlate maxillary morphometric measurements with (1) the anatomic level of obstruction during DISE and (2) the apnea-hypopnea index on polysomnography. METHODS: We made a cross-sectional analysis of patients with obstructive sleep apnea undergoing DISE in search of positive airway pressure alternative treatment. Maxillary measurements were collected from a computed tomography scan (interpremolar distance, intermolar distance [IMD] and sella-nasion A point angle), findings from DISE, and sleep study variables from polysomnography. Correlation between computed tomography, DISE, and polysomnography data was assessed using Pearson's correlation, and receiver operating characteristic curves were determined for each facial measurement. RESULTS: Sixty-nine patients were included in the study. The group with velopharyngeal circumferential collapse had mean IMD = 26.30 mm (25.5-31.45), and the group with anteroposterior collapse had mean IMD = 29.20 mm (26.8-33.10; P = .040). The group with complete tongue-base obstruction had mean interpremolar distance = 26.40 mm (25.1-28) and IMD = 26.30 mm (25.6-28.4), and the group without obstruction had mean interpremolar distance = 28.7 mm (27.2-30; P = .003) and IMD = 34.06 mm (32.1-37; P < .001). The receiver operating characteristic curve determined an IMD cutoff of 29.8 mm for predicting tongue-base obstruction. CONCLUSIONS: The maxillary transverse deficiency, identified by reduction in interpremolar distance and IMD, predicted the occurrence of complete tongue-base obstruction, complete concentric collapse at the velopharynx, and multilevel obstruction during DISE. We did not find an association between the maxillary measurements and obstructive sleep apnea severity. These associations hold some promise in ultimately supplanting insights previously available only through DISE.

Nasal vs. oronasal mask during PAP treatment: a comparative DISE study.

PURPOSE: The present study evaluated the upper airway pattern of obstruction in individuals undergoing drug-induced sleep endoscopy (DISE) exam with positive airway pressure (PAP), and compared this effect through a nasal or oronasal mask. METHODS: Prospective study. Patients requiring PAP due to obstructive sleep apnea (OSA) were evaluated through DISE at three different moments: (1) a baseline condition (without PAP); (2) PAP treatment with a nasal mask; and (3) PAP with an oronasal mask at the same pressure. The conditions were compared intra-individually, following VOTE classification. A TOTAL VOTE score (the sum of VOTE scores observed for each anatomical site) was also applied to compare intra-individual results. RESULTS: Thirteen patients were enrolled in the study. All patients presented multi-level pharyngeal obstruction at baseline condition. In six patients, the pattern of obstruction differed according to the mask. Nasal mask significantly decreased the obstruction score when compared with baseline condition both in velum (P value < 0.05) and oropharynx regions (P value < 0.005). TOTAL VOTE score was also significantly lower during nasal mask evaluation when compared with basal condition (P value < 0.005). Remarkably, oronasal mask with the same pressure was not as effective as nasal masks. Obstruction levels observed at the tongue base or epiglottis levels were more resistant to PAP treatment. CONCLUSIONS: Collapse in velum and oropharyngeal sites is more compliant to PAP than obstruction at lower levels of the pharynx, either with nasal or oronasal masks. Nasal mask is superior to prevent pharyngeal collapse than oronasal devices under the same pressure.

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.

Propofol-induced sleep: polysomnographic evaluation of patients with obstructive sleep apnea and controls.

OBJECTIVE: The localization of upper airway obstruction in patients with obstructive sleep apnea (OSA) may optimize treatment. Nasoendoscopy during propofol sedation allows such an evaluation, but the effect of this drug on respiratory patterns and muscle relaxation is unknown. The objective of the present study was to determine through polysomnography whether propofol would change sleep parameters. STUDY DESIGN: Prospective study of subjects submitted to polysomnography under sedation with propofol. SETTING: Tertiary referral center. SUBJECTS AND METHODS: Fifteen non-obese subjects (4 controls/11 OSA patients) were submitted to two diurnal polysomnograms (90-120 minutes of sleep), with and without the use of propofol. The parameters presence of snoring, apnea-hypopnea index (AHI), oxygen desaturation, and sleep architecture were compared. RESULTS: The use of propofol did not induce snoring in the control subjects, whereas 100 percent of the OSA patients snored. AHI and mean oxygen saturation (SaO(2)) did not differ significantly between examinations with and without sedation. However, minimum SaO(2) differed significantly (P < 0.05) with sedation, being lower during propofol sedation. Propofol also significantly changed the sleep architecture, with a significant increase in N3 sleep (P < 0.005) and total abolishment of rapid eye movement sleep (P < 0.0005) during propofol sedation. CONCLUSIONS: These preliminary results allow us to infer that sedation with propofol changes sleep architecture but permits respiratory evaluation, because the main respiratory parameters evaluated in OSA are maintained. These preliminary results support the view that nasoendoscopy under propofol sedation is a promising examination for management of this disease.