Gastric stimulation: influence of electrical parameters on gastric emptying in control and diabetic rats

BACKGROUND: The aim of this study was to test the effect of different pulse frequencies and amplitudes during gastric stimulation (GS) on gastric emptying in the rat. METHODS: GS was performed in 2 groups of laparotomized rats: healthy control animals, and rats with acute diabetes. The effects of four pulse frequencies (0.5, 1, 10, 20 Hz) and three pulse amplitudes (5, 20, 40 mA) were tested. The volumes emptied from the stomach after the oro-gastric instillation of a nutrient solution were compared to those obtained in animals without GS. Intragastric pH values were assessed under basal conditions and after GS. RESULTS: In both groups, GS increased emptied volumes compared to conditions without stimulation (p < 0.05) for pulse frequencies above 0.5 Hz. Increases in pulse frequencies accelerated gastric emptying (p < 0.01) with a plateau at around 10 Hz. The increase in pulse amplitudes resulted in larger emptied volumes only when the pulse frequency was 1 Hz (p < 0.04) while the opposite effect was observed at 20 Hz (p < 0.04). The most effective combinations to enhance gastric emptying compared to baseline conditions were 10 Hz with 5 or 20 mA. The overall effect of GS on gastric emptying compared to baseline conditions without stimulation, was greater in diabetic than in controls rats (p < 0.05). During stimulation, intragastric pH values were not different from basal conditions during fasting or after a meal in control and diabetic rats. CONCLUSIONS: Although both pulse frequency and amplitude should be considered during GS, frequency appears to be the most critical point. The possibility of increasing gastric emptying by electrical stimulation in diabetic rats suggests potential clinical applications for this method

Development and evaluation of a patient centered cardiovascular health education program for insured patients in rural Nigeria (QUICK - II)

<p>Abstract</p> <p>Background</p> <p>In Sub Saharan Africa, the incidence of hypertension and other modifiable cardiovascular risk factors is growing rapidly. Poor adherence to prescribed prevention and treatment regimens by patients can compromise treatment outcomes. Patient-centered cardiovascular health education is likely to improve shortcomings in adherence. This paper describes a study that aims to develop a cardiovascular health education program for patients participating in a subsidized insurance plan in Nigeria and to evaluate the applicability and effectiveness in patients at increased risk for cardiovascular disease.</p> <p>Methods/Design</p> <p><it>Design: </it>The study has two parts. Part <it>1 </it>will develop a cardiovascular health education program, using qualitative interviews with stakeholders. Part <it>2 </it>will evaluate the effectiveness of the program in patients, using a prospective (pre-post) observational design.</p> <p><it>Setting: </it>A rural primary health center in Kwara State, Nigeria.</p> <p><it>Population: </it>For part 1: 40 patients, 10 healthcare professionals, and 5 insurance managers. For part 2: 150 patients with uncontrolled hypertension or other cardiovascular risk factors after one year of treatment.</p> <p><it>Intervention: </it>Part <it>2</it>: patient-centered cardiovascular health education program.</p> <p><it>Measurements: </it>Part 1: Semi-structured interviews to identify stakeholder perspectives. Part 2: Pre- and post-intervention assessments including patients' demographic and socioeconomic data, blood pressure, body mass index and self-reporting measures on medication adherence and perception of care. Feasibility of the intervention will be measured using process data.</p> <p><it>Outcomes: </it>For program development (part 1): overview of healthcare professionals' perceptions on barriers and facilitators to care, protocol for patient education, and protocol implementation plan.</p> <p>For program evaluation (part 2): changes in patients' scores on adherence to medication and life style changes, blood pressure, and other physiological and self-reporting measures at six months past baseline.</p> <p><it>Analysis: </it>Part 1: content analytic technique utilizing MAXQDA software. Part 2: univariate and multilevel analysis to assess outcomes of intervention.</p> <p>Discussion</p> <p>Diligent implementation of patient-centered education should enhance adherence to cardiovascular disease prevention and management programs in low income countries.</p> <p>Trial Registration</p> <p><a href="http://www.controlled-trials.com/ISRCTN47894401">ISRCTN47894401</a></p