Changing clinical practice. Prospective study of the impact of continuing medical education and quality assurance programs on use of prophylaxis for venous thromboembolism

OBJECTIVE: To determine the effect of continuing medical education (CME) with and without a quality assurance component (CME+QA) on physician practices in the prevention of venous thromboembolism. METHODS: A communitywide study was performed in 15 short-stay hospitals in central Massachusetts. The study population included 3158 patients in acute-care hospitals with multiple risk factors for venous thromboembolism. Study hospitals were randomly assigned to one of two educational strategies or to a control group that received no intervention. RESULTS: The proportion of patients at high risk for venous thromboembolism who received effective methods of prophylaxis increased significantly from 29% in 1986 to 52% in 1989 (P < .001). This increase was seen in all study groups: control hospitals, 40% to 51% (P < .001); CME hospitals, 21% to 49% (P < .0001); and CME+QA hospitals, 27% to 55% (P < .0001). The increase in prophylaxis use from 1986 to 1989 was significantly greater among patients cared for in hospitals whose physicians participated in a formal CME program (an increase of 28%) than in control hospitals (an increase of 11%) (P < .001). There was no significant difference in the use of prophylaxis in hospitals whose physicians received CME+QA interventions compared with hospitals whose physicians received CME interventions alone (identical increases of 28%). CONCLUSION: A formal CME program significantly increased the frequency with which physicians prescribed prophylaxis for venous thromboembolism. We believe the key factor in our CME interventions that motivated clinicians to change their practices was the provision of hospital-specific data demonstrating a compelling need for improvement. Despite the substantial investment by hospitals in QA, traditional QA intervention appeared to provide no additional benefit. Even after extensive CME/QA interventions, prophylaxis for venous thromboembolism remained underutilized, suggesting the need to develop new approaches to changing clinical practice.     

Links between physical fitness and cardiovascular reactivity and recovery to psychological stressors: A meta-analysis.

A meta-analysis of published studies with adult human participants was conducted to evaluate whether physical fitness attenuates cardiovascular reactivity and improves recovery from acute psychological stressors. Thirty-three studies met selection criteria; 18 were included in recovery analyses. Effect sizes and moderator influences were calculated by using meta-analysis software. A fixed effects model was fit initially; however, between-studies heterogeneity could not be explained even after inclusion of moderators. Therefore, to account for residual heterogeneity, a random effects model was estimated. Under this model, fit individuals showed significantly attenuated heart rate and systolic blood pressure reactivity and a trend toward attenuated diastolic blood pressure reactivity. Fit individuals also showed faster heart rate recovery, but there were no significant differences in systolic blood pressure or diastolic blood pressure recovery. No significant moderators emerged. Results have important implications for elucidating mechanisms underlying effects of fitness on cardiovascular disease and suggest that fitness may be an important confound in studies of stress reactivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Electronic sensor for the determination of fruit and vegetable respiration

An instrument to measure the respiration rate of whole fruits and vegetables was designed and developed using a pressure variation method. The Motorola MPX-10-DP pressure transducer was used to monitor pressure changes due to respiratory activity. The operating procedures and calculations required to determine respiration rate (RR) in terms of CO₂ produced, RR-CO₂, and O₂ consumed, RR-O₂, with the respirometer were simple. The values of RR-CO₂ and RR-O₂ obtained by the pressure variation method were compared to changes in CO₂ and O₂ concentrations as determined by gas chromatography. The results showed no significant difference (0.05 level) between the two methods.     

Patency of 24-gauge peripheral intermittent infusion devices: a comparison of heparin and saline flush solutions

The purpose of this study was to compare the effectiveness of heparin and normal saline flush solutions in maintaining the patency of 24-gauge peripheral intermittent infusion devices (PIIDs). A prospective, non-randomized, sequential, blinded study design was conducted on a pediatric and a neonatal intensive care unit. The sample consisted of 134 catheters in 61 patients. Heparin and saline flush groups were similar for age, PIID placement site, irritating substances infused, and initial IV function. The median duration of catheters flushed with heparin was 42 hours and with saline was 35.3 hours. Kaplan-Meier Survival Analysis indicated that the duration of catheters flushed with heparin was significantly longer than those flushed with saline (p = .02). More catheters flushed with saline were removed because of problems (p = .027). Results of this study suggest that heparin is more effective than saline in maintaining the patency of small, 24-gauge catheters.     

Characteristics of ANP-binding sites in the adrenal capsules of term-pregnant rats

Magnetic resonance imaging (MRI) of the cervical spine was performed on 20 patients (mean age 10 years) with a preliminary diagnosis of juvenile rheumatoid arthritis (JRA). In all patients conventional x-rays of the cervical spine were obtained, and the relationship between clinical status and MRI findings were evaluated. Two patients with clinical manifestations, including neck pain and diminished range of motion, exhibited significant pathologic features on radiogram and MRI, the latter providing more detailed information. Among 18 patients who had no complaints about their cervical spines, 3 patients (65%) had either soft tissue involvement, pannus formation or erosions on the surface of atlantoaxial joints; only four patients (20%) had erosions on plain x-ray views. Since the early diagnostic ability of MRI in JRA allows early therapeutic intervention, every patient with a probable diagnosis of JRA would benefit from MRI.     

Microwave-Rectification RFI Response in Field-Effect Transistors

This paper discusses the rectification of microwave energy in low-medium frequency feld-effect transistors (FET's) and develops a small-signal model for RHI noise analysis in low-frequency linear circuitry. The modeling procedure centers on a Taylor series expansion of the gate voltage-drain current characteristic which shows a small increase in drain current due to a nicrowave voltage at the gate. The increase in drain current is proportional to the variation in transconductance with gate voltage, and the square of the microwave voltage. Analysis of the microwave power in the transistor shows that critical parameters in determnination of the sensitivity are the gate capacitance and the real part ofthe device input impedance, which ultimately is limited by the parasitic resistance between the active channel and contacts.     

Development of a structural optimization strategy for the design of next generation large thermoplastic wind turbine blades

This paper presents the development of a structural optimization process for the design of future large thermoplastic wind turbine blades. The optimization process proposed in this paper consists of three optimization steps. The first step is a topology optimization of a short untwisted and non tapered section of the blade, with the inner volume used as the design domain. The second step is again a topology optimization, but on the first half of a blade to study the effect of non symmetry of the structure due to blade twist and taper. Results of this optimization step are then interpreted to build a shell model of the complete blade structure to perform composite size optimization based on a minimum mass objective subjected to constraints on deflection, composite strength and structural stability. Different blade models using ribs are then optimized and compared against conventional blade structure (box spar structure without ribs and single web structure without ribs). The use of ribs in wind turbine blade structures, which is more adapted to thermoplastic composite manufacturing than for thermoset composites, leads to slightly lighter blades than conventional blade structures.