Subarctic Atmospheric Aerosol Composition: 2. Hygroscopic Growth Properties

Subarctic aerosols were sampled during July 2007 at the Abisko Scientific Research Station Stordalen site in northern Sweden with an instrument setup consisting of a custombuilt Hygroscopicity Tandem Differential Mobility Analyzer (HTDMA) connected in series to a single particle mass spectrometer. Aerosol chemical composition in the form of bipolar single particle mass spectra was determined as a function of hygroscopic growth both in situ and in real time. The HTDMA was deployed at a relative humidity of 82%, and particles with a dry mobility diameter of 260 nm were selected. Aerosols from two distinct air masses were analyzed during the sampling period. Sea salt aerosols were found to be the dominant particle group with the highest hygroscopicity. High intensities of sodium and related peaks in the mass spectra were identified as exclusive markers for large hygroscopic growth. Particles from biomass combustion were found to be the least hygroscopic aerosol category. Species normally considered soluble (e.g., sulfates and nitrates) were found in particles ranging from high to low hygroscopicity. Furthermore, the signal intensities of the peaks related to these species did not correlate with hygroscopicity

Subarctic atmospheric aerosol composition: 1. Ambient aerosol characterization

Subarctic aerosol was sampled during July 2007 at the Abisko Research Station Stordalen field site operated by the Royal Swedish Academy of Sciences. Located in northern Sweden at 68 degrees latitude and 385 m above sea level (m asl), this site is classified as a semicontinuous permafrost mire. Number density, size distribution, cloud condensation nucleus properties, and chemical composition of the ambient aerosol were determined. Back trajectories showed that three distinct air masses were present over Stordalen during the sampling period. Aerosol properties changed and correlated with air mass origin to the south, northeast, or west, suggesting that particle source and transport were important factors. We observe that Arctic aerosol is not compositionally unlike that found in the free troposphere at midlatitudes. Internal mixtures of sulfates and organics, many on insoluble biomass burning and/or elemental carbon cores, dominate the number density of particles from similar to 200-to 2000-nm aerodynamic diameter. Mineral dust that had interacted with gas-phase species was observed in all air masses. Sea salt, due to the uptake of nitrate species and loss of chlorine, was the aerosol type that most varied chemically with air mass

Effect evaluation of an interprofessional medication therapy management approach for multimorbid patients in primary care: a cluster-randomized controlled trial in community care (WestGem study protocol)

Background: Pharmaceutical practice worldwide is developing towards patient care. Medication Review (MR) and Medication Therapy Management (MTM) are evolving as the most prominent services in pharmaceutical care and have a strong potential to provide a large benefit for patients and society. MTMs can only be performed in an interprofessional, collaborative setting. Several international studies have explored the effects of a MTM on the quality of therapy and costs. For Germany the data is still deficient. This study aims to provide data on the effects of an interprofessional MTM regarding quality of therapy, quality of life, costs and cost-effectiveness. Method/Design: The study is designed as a cluster-randomized controlled trial in primary care, involving 12 outpatient clinics (clusters) and 165 patients. Primary care units are allocated to interventions using a Stepped Wedge Design. All units are initially assigned to the control group. After a 6 month observation period, general practitioners (GP) are randomly allocated to one of three groups and the interprofessional medication therapy management approach is implemented sequentially per each group with a lag of 3 months between. The primary outcome is the change in the quality of therapy measured by the MAI (Medication Appropriateness Index). Secondary outcomes include changes in the number of drug related problems, medication complexity, changes in drug-adherence, changes in health-status and function, quality of life, direct costs and the incremental cost-effectiveness ratio. The acceptance of the interprofessional Medication Therapy Management approach is assessed by qualitative methods. Discussion: The patient interview and brown bag review are activities, typically provided by the pharmacist. In this trial the patient is blinded to the pharmacist. The strength of having the patient blinded to the pharmacists is to exclude skepticism of the patient toward unknown pharmacies, which might be a major confounder in a regional and community setting. A weakness is that some patient related data might reach the pharmacists in a way, which might differ from self-acquired data

Is applanation tonometry a reliable method for monitoring blood pressure in morbidly obese patients undergoing bariatric surgery?

Background: The aim of this study was to evaluate the validity of non-invasive continuous BP measurement by applanation tonometry in morbidly obese patients undergoing bariatric surgery. Methods: Arterial blood pressure (AP) was recorded intraoperatively both by applanation tonometry (AT) (T-Line 200pro, Tensys Medical(R), USA) and an arterial line (AL) after radial cannulation in obese patients undergoing bariatric surgery. Discrepancies between the two methods were assessed as bias, limits of agreement and percentage error. Mean, systolic, and diastolic arterial pressures were assessed (MAP, SAP, DAP respectively). Trending ability was assessed by concordance based on four-quadrant plotting. Results: Mean (SD) BMI of the 28 patients was 49.4 (9.7 kg m(-2)). A total of 201 907 time points were available for analysis. Bias for MAP(AT) compared with MAP(AL) was +3.97 mm Hg (SAP(AT) + 3.45 mm Hg; DAP(AT) +3.66 mm Hg) with limits of agreement for MAP(AT) of -14.47 and +22.41 mm Hg (SAP(AT) -22.0 and +28.9 mm Hg; DAP(AT) -15.7 and +23.1 mm Hg). Percentage error for MAP(AT) was 23.5% (23.4% for SAP(AT); 30.5% for DAP(AT)). Trending ability for MAP, SAP, and DAP revealed a concordance of 0.74, 0.72, and 0.71, respectively. Conclusions: Continuous BP assessment by applanation tonometry is feasible in morbidly obese patients undergoing bariatric surgery. However, despite a low mean difference, 95% limits of agreement and trending ability indicate that the technology needs to be improved further, before being recommended for routine use in this group of patients

Implantation of venous access devices under local anesthesia: patients’ satisfaction with oral lorazepam

De-Hua Chang,1 Sonja Hiss,1 Lena Herich,2 Ingrid Becker,2 Kamal Mammadov,1 Mareike Franke,1 Anastasios Mpotsaris,1 Robert Kleinert,3 Thorsten Persigehl,1 David Maintz,1 Christopher Bangard1 1Department of Radiology, 2Institute of Medical Statistics, Informatics and Epidemiology, 3Department of Surgery, University Hospital of Cologne, Cologne, Germany Objective: The aim of the study reported here was to evaluate patients’ satisfaction with implantation of venous access devices under local anesthesia (LA) with and without additional oral sedation.Materials and methods: A total of 77 patients were enrolled in the prospective descriptive study over a period of 6 months. Subcutaneous implantable venous access devices through the subclavian vein were routinely implanted under LA. Patients were offered an additional oral sedative (lorazepam) before each procedure. The level of anxiety/tension, the intensity of pain, and patients’ satisfaction were evaluated before and immediately after the procedure using a visual analog scale (ranging from 0 to 10) with a standardized questionnaire.Results: Patients’ satisfaction with the procedure was high (mean: 1.3±2.0) with no significant difference between the group with premedication and the group with LA alone (P=0.54). However, seven out of 30 patients (23.3%) in the group that received premedication would not undergo the same procedure without general anesthesia. There was no significant influence of lorazepam on the intensity of pain (P=0.88). In 12 out of 30 patients (40%) in the premedication group, the level of tension was higher than 5 on the visual analog scale during the procedure. In 21 out of 77 patients (27.3%), the estimate of the level of tension differed between the interventionist and the patient by 3 or more points in 21 out of 77 patients (27.3%).Conclusion: Overall patient satisfaction is high for implantation of venous access devices under LA. A combination of LA with lorazepam administered orally might not be adequate for patients with a high level of anxiety and tension. The level of tension is often underestimated by the interventionist. Pre-procedural standardized questionnaires could be used to identify patients for whom a gradual approach of individualized sedation may be more effective. Keywords: patient satisfaction, pain, supportive care, chemotherapy, central venous port implantatio