Track E Implementation Science, Health Systems and Economics

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138412/1/jia218443.pd

Continuous measurements of renal perfusion in pigs by means of intravascular Doppler

Continuous measurements of renal perfusion in pigs by means of intravascular Doppler.BackgroundChanges in renal blood flow are considered to play a significant role in the induction and maintenance of kidney failure, but are difficult to monitor with currently available techniques. The objective was to validate renal flow measurements with Doppler guidewires and to apply this technique to assess dose and time dependency of the renal vascular effects of norepinephrine (NE).MethodsIn 10 anesthetized pigs, flow velocity in renal arteries (FVart) and veins (FVvein) and volumetric renal blood flow (VBF) were measured before and after intravenous bolus application of incremental doses of NE (2 to 200 μg).ResultsFVart curves exactly reflected the changes in VBF. Beat-to-beat analysis revealed a strong linear correlation over a mean VBF range of less than 0.05 to 0.35 L/min (median correlation coefficient with FVart, r = 0.998), and significant but less close relationships were also found between VBF and FVvein. Ten seconds after the administration of 200 μg NE, FVart dropped from 71 to 6 cm/sec and was 90% reversible after 48 seconds. Similarly, the renal vascular resistance temporarily rose from 988 to 13711 mm Hg · min/L. In contrast, NE-induced increases in systemic vascular resistance were on average a maximum of 1.5-fold but persisted for more than 60 seconds.ConclusionsDoppler flow measurements in the renal artery provide an excellent surrogate of volumetric blood flow, which may be useful for continuous monitoring of renal hemodynamics. The renal vasculature is more sensitive when compared with the systemic vasculature, but also appears to evoke more efficient counter-regulatory mechanisms in response to NE

Process evaluation of school-based peer education for HIV prevention among Yemeni adolescents

<p>In 2005, a survey was conducted among all the 27 high schools of Aden, which revealed low levels of knowledge on major prevention measures, and a high level of stigma and discrimination towards people living with HIV (PLWH). The results served as a baseline for implementing a school-based peer education intervention for HIV prevention in the 27 schools of Aden. In 2008, and after 3 years of implementation, a quasi-experimental evaluation was conducted, which revealed that the peer education intervention has succeeded in improving HIV knowledge and skills; and in decreasing stigmatization of PLWH. This process evaluation aims to give a deeper understanding of the quasi-experimental evaluation which was conducted in the 27 high schools of Aden, and to highlight the factors that facilitated or inhibited school peer education in such a conservative Muslim setting. Qualitative methodologies were pursued, where 12 focus group discussions and 12 in-depth interviews were conducted with peer educators, targeted students, school principals, social workers, and parents of peer educators. Results revealed that school-peer education was well received. There was an apparent positive effect on the life skills of peer educators, but the intervention had a lesser effect on targeted students. Key enabling factors have been the high quality of training for peer educators, supportive school principals, and acceptance of the intervention by parents. These findings are important for improving the life skills and peer education intervention at the school level, and in better planning and implementation of life skills and peer programmes at a national scale.</p>