This study was designed to determine which method of measuring the systolic blood pressure is more accurate when determining the ankle/brachial index (ABI), which is an important tool in assessing graft patency for patients who have had peripheral vascular surgery. The accuracy of the stethoscope diaphragm was compared with the stethoscope bell and Doppler methods used to measure the brachial systolic pressure. These pressures were then used in the calculation of the ABI and then the ABI was compared by method and time since surgery. The theoretical framework for this study was drawn from theories on sound generation, transmission and measurement. This study used a two-repeated measures design in which the subjects served as their own control. The results were then analyzed using an ANOVA specific to a two-repeated measures design. The sample consisted of 31 subjects which comprised 80% of all peripheral vascular surgery patients admitted over a two month period to a large tertiary care hospital in Western Canada. The subjects ranged in age from 47 to 82 years, the majority had at least one other medical condition in addition to peripheral vascular disease, were on a variety of medications, and 35% had had previous vascular surgery. The subjects had their brachial systolic blood pressure measured by the three methods on the third, fourth and fifth postoperative day. At the same time they also had their dorsalis pedis and posterior tibial pressures measured by the Doppler method. There was no significant difference in the brachial systolic blood pressure related to the methods used to take the blood pressure, the postoperative day that the blood pressure was measured, nor was there any interaction between method and occasion. Also, there was no significant difference in either the dorsalis pedis or posterior tibial ankle/brachial indices related to method used to measure the brachial systolic blood pressure, the postoperative day the measurement was taken, nor any interaction between method and occasion. The findings suggest that peripheral vascular surgery patients often have systolic pressures that differ between the right and left arm which would make a major difference in the calculation of the ABI. Therefore, the pressures should be measured in both arms, followed by documentation and consistent use of the arm with the highest pressure when determining the ABI. The findings also suggest that inservice education and periodic skill checking be implemented when the nurse is required to employ the Doppler method owing to the number of variables to consider when operating this instrument. / Applied Science, Faculty of / Nursing, School of / Graduate

No description available.

Prior clinical studies have documented that high blood pressure is one of the prominent risk factors leading to cerebrovascular disease and subsequent cognitive impairment. The present study aims to examine the relationship between blood pressure and brain and cognitive function in a community sample. This study recruited 41 elderly persons aged 60–70. Multiple imaging modalities were adopted to assess white matter microstructure, regional brain volume, and resting-state neural activity while a set of neuropsychological tests was used to assess cognitive function. With blood pressure measured at clinical interview, correlation and regression analyses were performed. Results showed reduced white matter integrity with increased systolic blood pressure in the splenium of the corpus callosum and inferior longitudinal fasciculus in the absence of change in brain volume or neural activity. Also, increased systolic blood pressure was found to be correlated with poorer cognitive performance in information processing speed. The results held significant after controlling age, sex, and education. These observations of the subclinical sample suggest that high blood pressure relates to subtle changes in the brain and cognitive deficits. Blood pressure control, as a relatively modifiable factor, should be taken seriously in community-dwelling elderly. / published_or_final_version / Clinical Psychology / Doctoral / Doctor of Psychology

The purpose of this study was to assess the amount of sodium in the diet of normal adults. The population consisted of 86 adults, 49 females and 37 males, who were participants in the Family Heart Study (FHS). Of this population 26 were studied during the baseline assessment period and were just entering the program. The remaining 60 people were studied after participating in the FHS for one year. Three methods were used to assess sodium intake: a salt questionnaire, a salt preference test and the sodium content of a 24-hour urine collection. The salt questionnaire consisted of questions to assess the frequency of intake of high sodium foods and the use of salt at the table and in cooking. The salt preference test was done using a baked potato salted to taste by the participants. The salt questionnaire and salt preference test were compared to the amount of sodium in a 24-hour urine collection. There was no relationship among any of these measures of salt intake. The urinary analysis for sodium indicated that the participants in this study had a moderately high sodium intake (143 mEq/day), similar to other studies in the U.S. Males excreted more sodium than females. The group assessed at baseline and the group assessed after one year in the study both excreted the same amount of sodium. The year one group had switched to Lite salt and reduced their use of salt during cooking; however, they used salty foods with the same frequency as the baseline group. The urinalysis demonstrates that the changes made by the year one group were not significant in reducing their salt intake. The amount of sodium excreted showed no relationship to blood pressure. This finding is similar to other studies in the U.S. because most people consume over 70 mEq sodium/day, which is above the proposed threshold to prevent hypertension. The genetic variability in the U.S. population obscures any relationship of sodium intake to blood pressure. Some of the major problems in assessing sodium intake are the variability from day to day and the ubiquity of sodium in our foods. It was concluded that urinary assessment of sodium was the best method available at this time, although multiple collections are necessary to compensate for the variability of sodium intake. / Graduation date: 1981

No description available.

No description available.

No description available.

No description available.

Hypertension complicates approximately 10% of all pregnancies and is a leading cause of maternal and foetal mortality and morbidity world-wide. Pre-eclampsia is a major subgroup of these hypertensive disorders. It is defined as a rise in blood pressure to 140/90mm Hg or greater accompanied by proteinuria and usually presents after 20 weeks of pregnancy. Much of the early research into this disorder has concentrated on the determination of vasoactive compounds such as the renin-angiotensin system and prostacyclin. In the 1980's it was discovered that an inorganic free radical molecule, nitric oxide (NO), was released from the endothelium cell lining of the vasculature and was involved in regulating vasodilation of the vasculature walls via smooth muscle.It was also shown to have cytotoxic effects on bacteria, to inhibit platelet aggregation and to act as a neurotransmitter. The aim of this research was to assess the role of nitric oxide in preeclampsia. This was accomplished by the analysis of its oxidation products nitrite and nitrate in plasma from women with pre-eclampsia compared with those from normotensive pregnancies. A simple and robust assay for nitrite and nitrate was developed using ion chromatography. Initial experiments using isocratic elution with conductivity detection on a Dionex QIC system with an AS4A-SC column showed promise but were unsatisfactory due to the interference from chloride ions. Successive improvements to the technique involved changing the elution system to a gradient, initially to one with carbonate and subsequently to chloride, changing the detector system to direct UV detection at 214nm and changing the column to a high capacity, strong exchanger type. The resulting method shows good resolution, does not suffer from chloride overload and was simple to use. Control results for 200 serum samples showed that the male mean nitrite and nitrate levels were 3.34 ± 5.17 μmol L" and 42.1 ± 33.1 μmol L-1 respectively while female levels were 4.74 ± 11.7 μmol L-' and 37.5 ± 27.9 μmol L" respectively. Addition information on the free-radical status of the pregnant study groups was assessed by determination of lipid peroxides and the peroxynitrite product, 3-nitrotyrosine. An improved GC-MS method was developed to quantify total fatty acids and lipid peroxides. A new reversed phase HPLC technique for the analysis of free 3-nitrotyrosine in human plasma/serum was also developed although sample numbers were not as great as expected. Statistical analysis using F-tests, t-tests and the Mann-Whitney analysis did not show any difference in nitric oxide metabolites, lipids, lipid peroxides or peroxynitrite between gestation matched normotensive pregnant women and those with pre-eclampsia or pregnancy-induced hypertension. Published research has shown a vital role for nitric oxide in the maintenance of blood flow in normal pregnancy. This research does not support evidence for diminished or enhanced nitric oxide production in pre-eclampsia compared with normal pregnancy.

3 pp. / Revised