Friedman tongue position and cone beam computed tomography in patients with obstructive sleep apnea.

Objective: Evaluate the correlation between Friedman Tongue Position (FTP) and airway cephalometrics in patients with obstructive sleep apnea (OSA). Study Design: Retrospective review of adult patients with OSA undergoing Cone Beam Computed Tomography (CBCT). Methods: Collected data included age, sex, body mass index, apnea hypopnea index, FTP, and airway cephalometric parameters. Data analyses were performed using ANOVA, dichotomous t-testing, and linear regression. Results: 203 patients were included in the analysis. (M:F 132:71). The mean posterior airway space (PAS) was inversely correlated (p = 0.001, r =.119) with higher FTP grades with means of 12.3 mm, 7.9 mm, 6.6 mm, and 4.3 mm, I-IV respectively. Minimal cross-sectional area for patients with FTP I-IV was 245.7, 179.8, 137.6, and 74.2 mm, 2 respectively (p = 0.002, r = .095). Mean hyoid-mandibular plane (H-MP) for FTP I-IV was 20.6 mm, 20.4 mm, 24.7 mm, and 28.9 mm respectively. No statistically significant difference between H-MP values when comparing patients with FTP I or II (p = 0.22). There were statistically significant differences when these two groups were individually compared to FTP III and IV (p = 0.002). Linear regression analysis confirmed an independent association between FTP and PAS (ß = -2.06, p < 0.001), minimal cross-sectional area (ß = -45.07, p = 0.02), and H-MP (ß = 3.03, p = 0.01) controlling for BMI, age, AHI, and sex. Conclusions: Use of FTP is supported by objective CBCT cephalometric results, in particular the PAS, minimal cross-sectional area, and H-MP. Understanding the correlation between objective measurements of retroglossal collapse should allow Otolaryngologists to more confidently select patients who may require surgery to address the retroglossal area, particularly when the ability to perform cephalometric analysis is not possible. Level of Evidence: 4.

Predictors of habitual snoring and obstructive sleep apnea risk in patients with asthma.

BACKGROUND: A high prevalence of obstructive sleep apnea (OSA) symptoms was reported in patients with asthma. Our goal was to evaluate factors associated with habitual snoring and OSA risk in these patients. METHODS: Patients with asthma were surveyed at specialty clinics with the Sleep Apnea scale of the Sleep Disorders Questionnaire (SA-SDQ) and questions about the frequency of asthma symptoms (National Asthma Education and Prevention Program guidelines), followed by medical record review. SA-SDQ scores >or= 36 for men and >or= 32 for women defined high OSA risk. Logistic regression was used to model associations with habitual snoring and high OSA risk. RESULTS: Among 244 patients, 37% snored habitually and 40% demonstrated high OSA risk. Independent predictors of habitual snoring included gastroesophageal reflux disease (GERD) [odds ratio (OR), 2.19; 95% confidence interval (CI), 1.19 to 4.02] and use of an inhaled corticosteroid (ICS) [OR, 2.66; 95% CI, 1.05 to 6.72]. High OSA risk was predicted by asthma severity step (OR, 1.59; 95% CI, 1.23 to 2.06), GERD (OR, 2.70; 95% CI, 1.51 to 4.83), and ICS use (OR, 4.05; 95% CI, 1.56 to 10.53). Linear, dose-dependent relationships of ICS with habitual snoring and high OSA risk were seen (p = 0.004 and p = 0.0006, respectively). Women demonstrated a 2.11 times greater odds for high OSA risk (95% CI, 1.10 to 4.09) when controlling for the above covariates. CONCLUSIONS: Symptoms of OSA in patients with asthma are predicted by asthma severity, coexistent GERD, and use of an ICS in a dose-dependent fashion. The well-recognized male gender predominance for OSA symptoms is not apparent in these patients. Further exploration of these relationships may help to explain the increased prevalence of OSA in asthma and provide new insights into the reported female predominance of asthma morbidity.

Perineural administration of dexmedetomidine in combination with bupivacaine enhances sensory and motor blockade in sciatic nerve block without inducing neurotoxicity in rat.

BACKGROUND: The current study was designed to test the hypothesis that high-dose dexmedetomidine added to local anesthetic would increase the duration of sensory and motor blockade in a rat model of sciatic nerve blockade without causing nerve damage. METHODS: Thirty-one adult Sprague-Dawley rats received bilateral sciatic nerve blocks with either 0.2 ml bupivacaine, 0.5%, and 0.5% bupivacaine plus 0.005% dexmedetomidine in the contralateral extremity, or 0.2 ml dexmedetomidine, 0.005%, and normal saline in the contralateral extremity. Sensory and motor function were assessed by a blinded investigator every 30 min until the return of normal sensory and motor function. Sciatic nerves were harvested at either 24 h or 14 days after injection and analyzed for perineural inflammation and nerve damage. RESULTS: High-dose dexmedetomidine added to bupivacaine significantly enhanced the duration of sensory and motor blockade. Dexmedetomidine alone did not cause significant motor or sensory block. All of the nerves analyzed had normal axons and myelin at 24 h and 14 days. Bupivacaine plus dexmedetomidine showed less perineural inflammation at 24 h than the bupivacaine group when compared with the saline control. CONCLUSION: The finding that high-dose dexmedetomidine can safely improve the duration of bupivacaine-induced antinociception after sciatic nerve blockade in rats is an essential first step encouraging future studies in humans. The dose of dexmedetomidine used in this study may exceed the sedative safety threshold in humans and could cause prolonged motor blockade; therefore, future work with clinically relevant doses is necessary.

Correlates of daytime sleepiness in patients with asthma.

BACKGROUND AND PURPOSE: Patients with asthma often complain of daytime sleepiness, which is usually attributed to a direct effect of asthma on nocturnal sleep quality. We investigated this and other potential explanations for daytime sleepiness among asthmatics. PATIENTS AND METHODS: One hundred fifteen adult asthmatics were assessed for perceived daytime sleepiness (one question item), subjective sleepiness (Epworth Sleepiness Scale score, ESS), obstructive sleep apnea risk (Sleep Apnea scale score within Sleep Disorders Questionnaire, SA-SDQ), asthma severity step, relevant comorbid conditions, and current asthma medications. RESULTS: Among all subjects, 55% perceived excessive daytime sleepiness and 47% had ESS>10. Most subjects reported snoring (n=99, or 86%) and many snored habitually (n=44, 38%). The ESS correlated with SA-SDQ (P<0.0001), male gender (P=0.01), and asthma severity step (P=0.04). In a multiple regression model, the ESS was independently associated with SA-SDQ (P=0.0003) and male gender (P=0.02), but not with asthma severity step (P=0.51). There were no correlations between ESS and age, body mass index (BMI), forced expiratory volume in one second as percent of predicted value (FEV(1)%), comorbidities, or medication used to treat asthma. CONCLUSIONS: Sleepiness is common in asthmatics and may reflect occult obstructive sleep apnea more often than effects of asthma itself, other comorbid conditions, or asthma medications.

Sleep-disordered breathing in Michigan: a practice pattern survey.

OBJECTIVES: This survey sought to determine whether self-professed sleep specialists in the State of Michigan show practice variations in the diagnosis and management of sleep-disordered breathing (SDB), and whether such variations occur between pulmonologists and neurologists. METHODS: Questionnaires on practice volume and patterns during the prior 12 months were mailed to physician members of the Michigan Sleep Disorders Association ( n = 119); 67 were completed and returned. RESULTS: Respondents reported that they personally saw a median of 8 new patients each week for suspected SDB; estimates were that 86% of these patients were eventually confirmed to have SDB. Most patients (82%) had laboratory-based polysomnography after an initial clinic evaluation, and most (69%) of those treated for SDB received continuous positive airway pressure. However, practice patterns differed substantially among respondents, even when the analysis was limited to the 42 who reported board certification by the American Board of Sleep Medicine. For example, among all surveyed practices the likelihood that suspected SDB would be evaluated with a split-night diagnostic and treatment polysomnogram varied from 0 to 90%. The likelihood of SDB treatment with bilevel positive airway pressure varied from 0 to 50%, with automatically titrating devices from 0 to 100%, with surgery from 0 to 100% (0 to 50% among certified practitioners), and with oral appliances from 0 to 20%. The practice patterns of pulmonologists and neurologists did not differ significantly. CONCLUSION: Approaches to SDB vary widely in Michigan, though not according to clinician background in pulmonary medicine or neurology. A patient's experience, in both assessment and treatment, could differ substantially based on which clinician is consulted.