Publications by authors named "George C Dungan"

Background: Acute exacerbations of chronic obstructive pulmonary disease (COPD) in the emergency department (ED) involve dyspnea, cough, and chest discomfort; frequent exacerbations are associated with increased mortality and reduced quality of life. Noninvasive positive pressure ventilation (NiPPV) is commonly used to help relieve symptoms but is limited due to patient intolerance. We aimed to determine whether high-velocity nasal insufflation (HVNI) is noninferior to NiPPV in relieving dyspnea within 4 h in ED patients with acute hypercapnic respiratory failure.

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Xylazine exacerbates the respiratory depression induced by fentanyl. Because xylazine is a non-opioid, it is resistant to reversal by opioid receptor antagonists such as naloxone (e.g.

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Objective: All respiratory care represents some risk of becoming an aerosol-generating procedure (AGP) during COVID-19 patient management. Personal protective equipment (PPE) and environmental control/engineering is advised. High velocity nasal insufflation (HVNI) and high flow nasal cannula (HFNC) deliver high flow oxygen (HFO) therapy, established as a competent means of supporting oxygenation for acute respiratory distress patients, including that precipitated by COVID-19.

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Objective: To evaluate a prototype automated controller (IntellO) of the inspired fraction of oxygen (FiO) in maintaining a target range of oxygen saturation (SpO) in preterm babies receiving nasal high flow (HF) via the Vapotherm Precision Flow.

Design: Prospective two-centre order-randomised cross-over study.

Setting: Neonatal intensive care units.

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Objective/background: Although polysomnography (PSG) is the gold-standard measure for assessing disease severity in obstructive sleep apnea (OSA), it has limited value in identifying individuals experiencing significant neurobehavioural dysfunction. This study used a brief and novel computerised test battery to examine neurobehavioural function in adults with and without OSA.

Patients/methods: 204 patients with untreated OSA [age 49.

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Objective: Acutely restricting sleep worsens insulin sensitivity in healthy individuals whose usual sleep is normal in duration and pattern. The effect of recovery or weekend 'catch-up' sleep on insulin sensitivity and metabolically active hormones in individuals with chronic sleep restriction who regularly 'catch-up' on sleep at weekends is as yet unstudied.

Design: 19 men (mean ± SEM age 28·6 ± 2·0 years, BMI 26·0 ± 0·8 kg/m(2) ) with at least 6 months' history (5·1 ± 0·9 years) of lifestyle-driven, restricted sleep during the working week (373 ± 6·6 min/night) with regular weekend 'catch-up' sleep (weekend sleep extension 37·4 ± 2·3%) completed an in-laboratory, randomized, crossover study comprising two of three conditions, stratified by age.

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Purpose: Large quantities of neurophysiological electroencephalogram (EEG) data are routinely collected in the sleep laboratory. These are underutilised due to the burden of managing artefact contamination. The aim of this study was to develop a new tool for automated artefact rejection that facilitates subsequent quantitative analysis of sleep EEG data collected during routine overnight polysomnography (PSG) in subjects with and without sleep-disordered breathing (SDB).

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Although portable instruments have been used in the assessment of sleep disturbance for patients with low back pain (LBP), the accuracy of the instruments in detecting sleep/wake episodes for this population is unknown. This study investigated the criterion validity of two portable instruments (Armband and Actiwatch) for assessing sleep disturbance in patients with LBP. 50 patients with LBP performed simultaneous overnight sleep recordings in a university sleep laboratory.

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Rationale: Placebo responses are complex psychobiological phenomena and often involve patient expectation of benefit. With continuous positive airway pressure (CPAP) treatment of obstructive sleep apnoea, greater hours of CPAP use are associated with reduced sleepiness. However, these open-label studies have not controlled for patient expectation of benefit derived from their knowledge of hours of device use.

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Obstructive sleep apnoea (OSA) is often treated with autotitrating continuous positive airway pressure (autoCPAP) devices. Clinical and bench tests of these devices have suggested performance limitations. These studies do not indicate whether this is a failure to detect or a failure to respond to airway obstruction.

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Objectives: To study the acute effect of the new SensAwake CPAP modality (reducing pressure on awakenings) on wake after sleep onset (WASO) and other polysomnographic measures in patients with obstructive sleep apnea (OSA).

Study Design: Randomized crossover trial comparing an automatic continuous positive airway pressure device (AutoCPAP) with and without SensAwake on sleep architecture. CPAP naive patients received each therapy for a single night in the laboratory with at least 1-week washout.

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Introduction: It is unclear whether actimetry can be reliably used to measure sleep in severe obstructive sleep apnea (OSA) patients. We compared polysomnography (PSG) with actimetric assessment of sleep on an epoch-by-epoch basis in subjects with and without OSA.

Methods: 21 subjects were recorded with simultaneous overnight standard PSG and actimetry.

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