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Abstract Background Obstructive sleep apnea (OSA) is characterized by repetitive episodes of complete or partial obstruction of the upper airways during sleep. Conscious sedation for flexible bronchoscopy (FB) places patients in a sleep-like condition. We hypothesize that oxygen desaturation during flexible bronchoscopy may help to detect undiagnosed sleep apnea. Methods Single-centre, investigator-initiated and driven study including consecutive patients undergoing FB for clinical indication. Patients completed the Epworth Sleepiness Scale (ESS), Lausanne NoSAS score, STOP-BANG questionnaire and the Berlin questionnaire and underwent polygraphy within 7 days of FB. FB was performed under conscious sedation with propofol. Oxygen desaturation during bronchoscopy was measured with continuous monitoring of peripheral oxygen saturation with ixTrend (ixellence GmbH, Germany). Results 145 patients were included in the study, 62% were male, and the average age was 65.8 ± 1.1 years. The vast majority of patients (n = 131, 90%) proved to fulfill OSA criteria based on polygraphy results: 52/131 patients (40%) had mild sleep apnea, 49/131 patients (37%) moderate sleep apnea and 30/131 patients (23%) severe sleep apnea. Patients with no oxygen desaturation had a significantly lower apnea–hypopnea index than patients with oxygen desaturation during bronchoscopy (AHI 11.94/h vs 21.02/h, p = 0.011). This association remained significant when adjusting for the duration of bronchoscopy and propofol dose (p = 0.023; 95% CI 1.382; 18.243) but did not hold when also adjusting for age and BMI. Conclusion The severity of sleep apnea was associated to oxygen desaturation during flexible bronchoscopy under conscious sedation. Patients with oxygen desaturation during bronchoscopy might be considered for sleep apnea screening. Trial registration: The Study was approved by the Ethics Committee northwest/central Switzerland, EKNZ (EK 16/13) and was carried out according to the Declaration of Helsinki and Good Clinical Practice guidelines. Due to its observational character, the study did not require registration at a clinical trial registry.

Peter Grendelmeier, Michael Tamm, Kathleen Jahn, Eric Pflimlin, Daiana Stolz Clinic of Pulmonary Medicine and Respiratory Cell Research, University Hospital Basel, Petersgraben, Basel, Switzerland Background: Flexible bronchoscopy is increasingly used for diagnostic and therapeutic purposes. We aimed to examine the safety of flexible bronchoscopy with moderate sedation in patients with COPD. Methods: This study is a prospective, longitudinal, case–control, single-center study including 1,400 consecutive patients. After clinical and lung function assessments, patients were dichotomized in COPD or non-COPD groups. The primary end point was the combined incidence of complications. Results: The incidence of complications was similar in patients with and without COPD and independent of forced expiratory volume in the first second % predicted. Patients with COPD more frequently required insertion of a naso- or oropharyngeal airway; however, this difference was no longer significant after adjustment for age, gender, and duration of the procedure. Hypotension was significantly more common among patients with COPD. The number of episodes of hypoxemia ≤90% did not differ between the groups. However, patients with COPD had a lower mean and nadir transcutaneous oxygen saturation. Transcutaneous carbon dioxide tension (PtcCO2) change over the time course was similar in both groups, but both peak PtcCO2 and time on PtcCO2 >45 mmHg were higher in the COPD group. There were no differences in patient-reported outcomes. Conclusion: The safety of flexible bronchoscopy is similar in patients with and without COPD. This finding confirms the suitability of the procedure for both clinical and research indications. Keywords: bronchoalveolar lavage, propofol, complication, risk, respiratory insufficiency

Long-term potentiation (LTP) and neurogenesis in the dentate gyrus (DG) are correlated forms of hippocampal plasticity which share, under physiological conditions, common regulatory mechanisms. In Alzheimer's disease (AD), their alterations are potentially associated with the early cellular pathology and cognitive decline. We analyzed DG LTP and neurogenesis in B6.152H mice, an amyloid precursor protein and presenilin 2 double-transgenic mouse model of amyloidosis and observed that DG LTP was strongly enhanced before and after amyloid plaque formation. Whereas proliferation of DG neuronal progenitor cells was unchanged, survival of newborn neurons was strongly decreased already before plaque formation. As similar alteration of neurogenesis was observed in PS2APP mice without changes in DG LTP (Richards et al. 2003), this study suggests that enhanced synaptic plasticity did not rescue impaired neurogenesis, and supports decreased survival of newborn neurons as an early event associated with AD detectable even before plaque formation.

This paper considers the problem of obtaining good attitude estimates from measurements obtained from typical low cost inertial measurement units. The outputs of such systems are characterized by high noise levels and time varying additive biases. We formulate the filtering problem as deterministic observer kinematics posed directly on the special orthogonal group SO(3) driven by reconstructed attitude and angular velocity measurements. Lyapunov analysis results for the proposed observers are derived that ensure almost global stability of the observer error. The approach taken leads to an observer that we term the direct complementary filter. By exploiting the geometry of the special orthogonal group a related observer, termed the passive complementary filter, is derived that decouples the gyro measurements from the reconstructed attitude in the observer inputs. Both the direct and passive filters can be extended to estimate gyro bias online. The passive filter is further developed to provide a formulation in terms of the measurement error that avoids any algebraic reconstruction of the attitude. This leads to an observer on SO(3), termed the explicit complementary filter, that requires only accelerometer and gyro outputs; is suitable for implementation on embedded hardware; and provides good attitude estimates as well as estimating the gyro biases online. The performance of the observers are demonstrated with a set of experiments performed on a robotic test-bed and a radio controlled unmanned aerial vehicle. Index Terms--Attitude estimates, complementary filter, nonlinear observer, special orthogonal group.

BACKGROUND: Propofol is a sedative-hypnotic with a rapid onset of action. There are only limited data evaluating propofol for flexible bronchoscopy. We analysed the feasibility and safety of propofol for bronchoscopy in a high output tertiary care centre. METHODS: Prospective data on patients undergoing flexible bronchoscopy at the University Hospital Basel, Switzerland, were analysed. Patient demographics, ASA class, Mallampati class, indication for bronchoscopy, bronchoscopic procedures, duration of examination, medication requirements, minor and major adverse events, haemodynamic parameters, as well as cough scores during the procedure were documented. Patients were followed up to discharge from the bronchoscopy suite. RESULTS: Data from 440 patients with a mean age 60 years (±15.5, 260 male) were analysed. The main indication for bronchoscopy was a suspicion of malignancy. The most common diagnostic procedures were bronchoalveolar lavage in 253 cases (31.5%) and bronchial washing in 174 cases (21.7%). The mean duration of the procedure was 19.6 min (±12.08). The mean propofol dose was 200 mg (±107.5) corresponding to 2.89 mg/kg (±1.70). Minor adverse events included oxygen desaturation in 72 (16.4%), hypotension in 68 (15.4%) and minor bleeding in 11 (2.5%) patients. No major adverse events were recorded. The median decline in systolic blood pressure after initiation of sedation was 14 mm Hg (3–28). A drop in systolic blood pressure greater than 20 mm Hg was observed in 166 of the 440 patients (37%). CONCLUSION: Propofol sedation for flexible bronchoscopy is feasible and safe.

Capnocytophaga canimorsus is a Gram‐negative rod commensal of oral cavity of dogs and cats. It can cause sepsis, septic shock, endocarditis, and meningitis associated with bites or licking wounds, especially in immunocompromised patients. Herein, we report a case of C. canimorsus spondylodiscitis linked to a dog bite in a previously healthy patient and review the literature on this pathogen. [ABSTRACT FROM AUTHOR]