ObjectivesThere are safety issues associated with propofol use for flexible bronchoscopy (FB). The bispectral index (BIS) correlates well with the level of consciousness. The aim of this study was to show that BIS-guided propofol infusion is safe and may provide better sedation, benefiting the patients and bronchoscopists.MethodsAfter administering alfentanil bolus, 500 patients were randomized to either propofol infusion titrated to a BIS level of 65-75 (study group) or incremental midazolam bolus based on clinical judgment to achieve moderate sedation. The primary endpoint was safety, while the secondary endpoints were recovery time, patient tolerance, and cooperation.ResultsThe proportion of patients with hypoxemia or hypotensive events were not different in the 2 groups (study vs. control groups: 39.9% vs. 35.7%, p = 0.340; 7.4% vs. 4.4%, p = 0.159, respectively). The mean lowest blood pressure was lower in the study group. Logistic regression revealed male gender, higher American Society of Anesthesiologists physical status, and electrocautery were associated with hypoxemia, whereas lower propofol dose for induction was associated with hypotension in the study group. The study group had better global tolerance (p<0.001), less procedural interference by movement or cough (13.6% vs. 36.1%, p<0.001; 30.0% vs. 44.2%, p = 0.001, respectively), and shorter time to orientation and ambulation (11.7±10.2 min vs. 29.7±26.8 min, p<0.001; 30.0±18.2 min vs. 55.7±40.6 min, p<0.001, respectively) compared to the control group.ConclusionsBIS-guided propofol infusion combined with alfentanil for FB sedation provides excellent patient tolerance, with fast recovery and less procedure interference.Trial RegistrationClinicalTrials. gov NCT00789815

achieve a target effect site (brain) concentration of propofol. However, patients may lose consciousness at variable effect site concentrations (Ce), with a higher Ce being associated with higher upper airway critical closing pressure.6,7 Most DISE procedures are started shortly after the patients lose consciousness. Objective:To evaluate the effect of sedation depth on druginduced sleep endoscopy (DISE). Methods: Ninety patients with obstructive sleep apnea (OSA) and 18 snorers underwent polysomnography and DISE under bispectral index (BIS)-guided propofol infusion at two different sedation levels: BIS 65-75 (light sedation) and 50-60 (deep sedation). Results: For the patients with OSA, the percentages of velopharynx, oropharynx, hypopharynx, and larynx obstructions under light sedation were 77.8%, 63.3%, 30%, and 33.3%, respectively. Sedation depth was associated with the severity of velopharynx and oropharynx obstruction, oropharynx obstruction pattern, tongue base obstruction, epiglottis anteroposterior prolapse and folding, and arytenoid prolapse. In comparison, OSA severity was associated with the severity of velopharynx obstruction, severity of oropharynx obstruction, and arytenoid prolapse (odds ratio (95% confi dence interval); 14.3 (4.7-43.4), 11.7 (4.2-32.9), and 13.2 (2.8-62.3), respectively). A good agreement was noted between similar DISE fi ndings at different times and different observers (kappa value 0.6 to 1, respectively 1 Drug-induced sleep endoscopy (DISE) has been used for decades to directly examine the upper airways in sedative-induced sleep and improve treatment outcomes by acting as an adjuvant tool to assess surgical or nonsurgical treatment options. 2-4Various sedation methods have been used to allow for the performance of DISE. Roblin introduced target-controlled infusion (TCI) of propofol to DISE to allow for better control of the sedation level.5 TCI of propofol uses computer-based pharmacokinetic and pharmacodynamic models to predict and Bispectral Index in Evaluating Effects of Sedation Depth on Drug-Induced Sleep EndoscopyYu-Lun Lo, MD BRIEF SUMMARYCurrent Knowledge/Study Rationale: Drug-induced sleep endoscopy (DISE) were performed under different sedative conditions and might affect upper airway obstructions. We aimed to evaluate the affects of sedation depth and obstructive sleep apnea severity on different upper airway obstruction patterns. Study Impact: Under DISE, sedation depth affected velopharynx and oropharynx obstruction severity, oropharynx obstruction pattern, tongue base obstruction, epiglottis anteroposterior prolapse and folding, and arytenoid prolapse; however, OSA severity was associated with velopharynx and oropharynx obstruction severity as well as arytenoid prolapse. Bispectral index guided DISE offers an objective and reproducible method to evaluate upper airway collapsibility.

BackgroundAlthough the prevalence of both obstructive sleep apnoea (OSA) and asthma are both increasing, little is known about the impact of OSA on the natural history of lung function in asthmatic patients.MethodsA total of 466 patients from our sleep laboratory were retrospectively enrolled. Of them, 77 patients (16.5%) had asthma with regular follow-up for more than 5 years. Their clinical characteristics, pulmonary function, emergency room visits, and results of polysomnography results were analysed.ResultsThe patients were divided into three groups according to the severity of the apnoea-hypopnea index (AHI). The decline in FEV1 among asthma patients with severe OSA (AHI > 30/h) was 72.4 ± 61.7 ml/year (N = 34), as compared to 41.9 ± 45.3 ml/year (N = 33, P = 0.020) in those with mild to moderate OSA (5 < AHI ≤ 30) and 24.3 ± 27.5 ml/year (N = 10, P = 0.016) in those without OSA (AHI ≤ 5). For those patients with severe OSA, the decline of FEV1 significantly decreased after continuous positive airway pressure (CPAP) treatment. After multivariate stepwise linear regression analysis, only AHI was remained independent factor for the decline of FEV1 decline.ConclusionsAsthmatic patients with OSA had substantially greater declines in FEV1 than those without OSA. Moreover, CPAP treatment alleviated the decline of FEV1 in asthma patients with severe OSA.