Publications by authors named "Stephen Hoffmann"

Rationale: More than a million polysomnograms (PSGs) are performed annually in the United States to diagnose obstructive sleep apnea (OSA). Third-party payers now advocate a home sleep test (HST), rather than an in-laboratory PSG, as the diagnostic study for OSA regardless of clinical probability, but the economic benefit of this approach is not known.

Objectives: We determined the diagnostic performance of OSA prediction tools including the newly developed OSUNet, based on an artificial neural network, and performed a cost-minimization analysis when the prediction tools are used to identify patients who should undergo HST.

View Article and Find Full Text PDF

Knowledge of the partitioning and sources of mercury are important to understanding the human impact on mercury levels in Lake Superior wildlife. Fluvial fluxes of total mercury (Hg(T)) and methylmercury (MeHg) were compared to discharge and partitioning trends in 20 sub-basins having contrasting land uses and geological substrates. The annual tributary yield was correlated with watershed characteristics and scaled up to estimate the basin-wide loading.

View Article and Find Full Text PDF

Rationale: Little is known about the consequences of intensivists’ work schedules, or intensivist continuity of care.

Objectives: To assess the impact of weekend respite for intensivists, with consequent reduction in continuity of care, on them and their patients.

Methods: In five medical intensive care units (ICUs) in four academic hospitals we performed a prospective, cluster-randomized, alternating trial of two intensivist staffing schedules.

View Article and Find Full Text PDF
Article Synopsis
  • ICU-acquired paresis (ICUAP) is common among critically ill patients, leading to longer hospital stays and prolonged ventilator use, but its direct link to mortality is debated due to patient severity variations.
  • The study conducted across five academic ICUs aimed to evaluate whether ICUAP is independently related to increased mortality and if handgrip dynamometry can serve as an effective strength measure.
  • Findings revealed that patients with ICUAP had significantly worse outcomes, with a notably higher mortality risk linked to both ICUAP and reduced handgrip strength, indicating the importance of assessing these factors in ICU settings.
View Article and Find Full Text PDF

The speciation or physicochemical form of copper and zinc in freshwater plays an important role in reactivity, bioavailability, and toxicity. Strong metal-binding ligands, which determine speciation, were detected by voltammetric methods, both anodic stripping voltammetry (ASV) and competitive ligand equilibration adsorptive stripping voltammetry (CLE-AdSV); the latter technique can detect nanomolar levels of extremely strong (log K' > 13) ligands. Through careful field site selection and the investigation of ultrafiltration permeate samples, natural organic ligands were measured with limited interferences of colloidal inorganic iron- and aluminum-based trace metal-binding phases.

View Article and Find Full Text PDF

Background: Critically ill patients require rapid care, yet they are also at risk for morbidity from the potential complications of that care. Computerized physician order entry (CPOE) is advocated as a tool to reduce medical errors, improve the efficiency of healthcare delivery, and improve outcomes. Little is known regarding the essential attributes of CPOE in the intensive care unit (ICU).

View Article and Find Full Text PDF

The physical and kinetic speciation of Cu and Zn in three impacted marine estuaries was examined. Contrasts in sources of metal-binding ligands, solution chemistry, and hydrologic forcing between and withinthethree study systems (Cape Fear River Estuary, North Carolina; Norfolk-Hampton Roads-Elizabeth River, Virginia; San Diego Bay, California) were exploited to enhance our understanding of Cu and Zn speciation. Trace metal-optimized tangential-flow ultrafiltration at 1 kDa nominal molecular weight limit (NMWL) was used to fractionate <0.

View Article and Find Full Text PDF

The National Heart, Lung and Blood Institute guidelines for the treatment of asthma suggest that inhaled corticosteroids, with the addition of a long-acting bronchodilator, may be the most effective long-term control medication for asthma. Five inhaled corticosteroids are approved for use in the USA, including beclomethasone dipropionate, budesonide, flunisolide, triamcinolone acetonide and fluticasone propionate. Fluticasone propionate (Flixotide) and the long-acting beta2 agonist salmeterol (Serevent), are now available in the USA together in an easy to use dry powder inhaler Advair.

View Article and Find Full Text PDF

Chronic inflammation in many pulmonary diseases, such as sarcoidosis and IPF, lead to end-stage lung disease and fibrosis. In other diseases, such as chronic thromboembolic disease and emphysema, long-term complications can result in pulmonary hypertension and cor pulmonale. Therapeutic options for end-stage lung disease are quite limited.

View Article and Find Full Text PDF