The effect of posture on airflow distribution, airway geometry and air velocity in healthy subjects.

Background: Gravity, and thus body position, can affect the regional distribution of lung ventilation and blood flow. Therefore, body positioning is a potential tool to improve regional ventilation, thereby possibly enhancing the effect of respiratory physiotherapy interventions. In this proof-of-concept study, functional respiratory imaging (FRI) was used to objectively assess effects of body position on regional airflow distribution in the lungs.

Functional imaging improves patient selection for mandibular advancement device treatment outcome in sleep-disordered breathing: a prospective study.

Study Objectives: Mandibular advancement devices (MADs) are a noninvasive treatment option for patients with obstructive sleep apnea (OSA) and act by increasing the upper airway volume. However, the exact therapeutic mechanism of action remains unclear. The aim of this study was to assess MAD mechanisms using functional imaging that combines imaging techniques and computational fluid dynamics and assess associations with treatment outcome.

Phenotypic Labelling Using Drug-Induced Sleep Endoscopy Improves Patient Selection for Mandibular Advancement Device Outcome: A Prospective Study.

Study Objectives: Mandibular advancement device (MAD) outcome varies between patients. We hypothesized that upper airway collapse sites, patterns, and degrees assessed during baseline drug-induced sleep endoscopy (DISE) affect MAD outcome.

Methods: One hundred patients with obstructive sleep apnea (OSA) were included and underwent baseline type 1 polysomnography.

Evaluation of a Trial Period With a Sleep Position Trainer in Patients With Positional Sleep Apnea.

Study Objectives: To assess the overall clinical effectiveness of a sleep position trainer (SPT) in patients with positional obstructive sleep apnea (POSA) and to evaluate how many patients were willing to continue treatment after a 1-month trial period.

Methods: Patients in whom POSA was diagnosed underwent a 1-month trial period with the SPT. Home sleep apnea tests were used to measure baseline data and data following the trial period with the SPT.

Development of a Clinical Pathway and Technical Aspects of Upper Airway Stimulation Therapy for Obstructive Sleep Apnea.

Obstructive sleep apnea (OSA) is a common disease with high morbidity and related mortality. Narrowing and collapse of the pharyngeal airway during sleep characterize the disease, resulting in a decrease (hypopnea) or a complete cessation (apnea) of oronasal airflow. Upper airway stimulation (UAS), using electrical neurostimulation of the hypoglossal nerve (n.

Determinants of Objective Compliance During Oral Appliance Therapy in Patients With Sleep-Disordered Breathing: A Prospective Clinical Trial.

Importance: The main reported reasons for discontinuation of oral appliance therapy for sleep-disordered breathing (SDB) are the presence of self-perceived adverse effects and self-appreciated lack of efficacy. However, these conclusions rely only on subjective compliance data.

Objective: To determine which parameters are correlated with objectively measured data on compliance with oral appliance therapy.

A promising concept of combination therapy for positional obstructive sleep apnea.

Purpose: The objective of this randomized controlled trial was to assess the additional effect of a chest-worn sleep position trainer (SPT) in patients with residual supine-dependent obstructive sleep apnea (sdOSA) under mandibular advancement device (MAD) therapy.

Methods: Baseline and follow-up polysomnography with MAD were performed. Twenty patients with sdOSA under MAD therapy underwent two consecutive randomized polysomnographies: one with SPT and one with combination of SPT + MAD.

Functional respiratory imaging as a tool to personalize respiratory treatment in patients with unilateral diaphragmatic paralysis.

A completely different treatment approach was chosen for 2 patients with unilateral diaphragmatic paralysis and complaints of dyspnea despite similar anatomic and physiologic abnormalities. These decisions were supported by results obtained by functional respiratory imaging (FRI). FRI generated functional information on lobar ventilation and local drug deposition.

Objectively measured vs self-reported compliance during oral appliance therapy for sleep-disordered breathing.

Background: Assessment of the overall therapeutic effectiveness of oral appliance therapy can only be realized through objectively measured compliance. The aims of this study were to assess objectively measured compliance during oral appliance therapy at 1-year follow-up and to compare these data with self-reported use.

Methods: Fifty-one eligible patients were enrolled in this 1-year prospective clinical study (men, 61%; mean age, 49 ± 10 years; apnea-hypopnea index, 18.

Objective measurement of compliance during oral appliance therapy for sleep-disordered breathing.

Background: Oral appliance (OA) therapy is increasingly prescribed as a non-continuous positive airway pressure treatment modality for sleep-disordered breathing (SDB). Although OA therapy is reported to be efficacious for the treatment of SDB, data on compliance remain limited to self-report.

Methods: In this 3-month prospective clinical trial, the main outcome was to assess the safety and feasibility of an objective measurement of compliance during OA therapy using an embedded microsensor thermometer with on-chip integrated readout electronics in 51 consecutive patients with an established diagnosis of SDB (AHI 18.

Implanted upper airway stimulation device for obstructive sleep apnea.

Objectives/hypothesis: Previous feasibility studies have shown that electrical stimulation of the hypoglossal nerve can improve obstructive sleep apnea (OSA). The current study examined the safety and preliminary effectiveness of a second generation device, the Upper Airway Stimulation (UAS) system, and identified baseline predictors for therapy success.

Study Design: Two consecutive open prospective studies.

Weight loss and sleep-disordered breathing in childhood obesity: effects on inflammation and uric acid.

Sleep-disordered breathing (SDB) is prevalent in childhood obesity. It may be an independent risk factor for the metabolic syndrome. Possible mechanisms are inflammation and oxidative stress.

Electrical stimulation of the hypoglossal nerve in the treatment of obstructive sleep apnea.

Upper airway occlusion in obstructive sleep apnea has been attributed to a decline in pharyngeal neuromuscular activity occurring in a structurally narrowed airway. Surgical treatment focuses on the correction of anatomic abnormalities, but there is a potential role for activation of the upper airway musculature, especially with stimulation of the hypoglossal nerve and genioglossus muscle. We present evidence from research on upper airway neuromuscular electrical stimulation in animals and humans.

Correlation between the severity of sleep apnea and upper airway morphology in pediatric and adult patients.

Purpose Of Review: Recent advances in upper airway imaging allow a better analysis of the upper airway morphology. With the increased accuracy of computed tomography, MRI and other imaging techniques, it becomes possible to identify very local changes in bony structure, soft tissues and lumen of the pharyngeal airway. These advances are able to provide new insights into obstructive sleep apnea (OSA) evaluation and treatment.

Upper airway mechanics.

This review discusses the pathophysiological aspects of sleep-disordered breathing, with focus on upper airway mechanics in obstructive and central sleep apnoea, Cheyne-Stokes respiration and obesity hypoventilation syndrome. These disorders constitute the end points of a spectrum with distinct yet interrelated mechanisms that lead to substantial pathology, i.e.

Sleep-disordered breathing: a new risk factor of suspected fatty liver disease in overweight children and adolescents?

Introduction: The aim of this retrospective study was to investigate if sleep-disordered breathing (SDB) was an independent predictor of suspected fatty liver disease in a clinical sample of overweight children and adolescents.

Materials And Methods: Consecutive overweight and obese children attending a pediatric obesity clinic underwent polysomnography, fasting blood sample, and abdominal ultrasound.

Results And Discussion: The respiratory disturbance index, percentage of total sleep time with SO2 < 90%, and SaO2nadir were associated with higher alanine amino-transferases (ALT) independent of abdominal obesity.

Sleep-disordered breathing, obesity, and airway inflammation in children and adolescents.

Background: To investigate the relationship between obstructive sleep apnea syndrome (OSAS) and exhaled nitric oxide (eNO) in overweight children and adolescents without asthma or atopy and to assess whether obesity per se is associated with increased airway inflammation.

Methods: Consecutive overweight subjects without symptoms of asthma or allergy were recruited at a pediatric obesity clinic. A normal-weight control group without OSAS and asthma or allergy was also recruited.

Comparison of a custom-made and a thermoplastic oral appliance for the treatment of mild sleep apnea.

Rationale: The efficacy of immediate adaptation of mandibular advancement devices made of thermoplastic material as a treatment option for sleep-disordered breathing (SDB) has been demonstrated in clinical studies. To date, there have been no studies comparing the efficacy of such prefabricated devices with custom-made devices.

Objectives: Our purpose was to compare the efficacy of both types of devices in patients with SDB.

Markers of inflammation and oxidative stress in patients undergoing CABG with CPB with and without ventilation of the lungs: a pilot study.

Cardiopulmonary bypass triggers systemic inflammation and systemic oxidative stress. Recent reports suggest that continuous ventilation during cardiopulmonary bypass (CPB) can affect the outcome of patients after cardiac surgery. We investigated the influence of lung ventilation on inflammatory and oxidative stress markers during coronary artery bypass graft (CABG) with CPB in 13 patients with (Group 2) or without (Group 1) ventilation of the lungs with small tidal volume (4 ml/kg).

Sleep-disordered breathing and uric acid in overweight and obese children and adolescents.

Objective: The aim of this study was to determine whether the severity of sleep-disordered breathing (SDB) was associated with increased levels of uric acid (UA), both in serum and in urine, as a marker of tissue hypoxia, in a sample of overweight and obese subjects, irrespective of indexes of adiposity.

Methods: Consecutive subjects underwent polysomnography, fasting blood sampling, and 24-h urine collection. Outcome parameters were serum UA, UA excretion ([24-h urinary UA x serum creatinine]/urine creatinine) and urinary UA/creatinine ratio.

Sleep-disordered breathing in overweight and obese children and adolescents: prevalence, characteristics and the role of fat distribution.

Aims: To determine the prevalence of sleep-disordered breathing (SDB) in a clinical sample of overweight and obese children and adolescents, and to examine the contribution of fat distribution.

Methods: Consecutive subjects without chronic lung disease, neuromuscular disease, laryngomalacia, or any genetic or craniofacial syndrome were recruited. All underwent measurements of neck and waist circumference, waist-to-hip ratio, % fat mass and polysomnography.

Effect of N-acetylcysteine on neutrophil activation markers in healthy volunteers: in vivo and in vitro study.

Background And Aims: Neutrophil activation is implicated in the pathogenesis of inflammatory processes such as chronic obstructive pulmonary disease (COPD). We wished to evaluate both in vivo and in vitro whether N-acetylcysteine (NAC) has an effect on the response of activated neutrophils.

Methods: Ten healthy volunteers took NAC (600 mg daily) for 14 days.