Indirect Blood Pressure Recordings Research Articles

Resveratrol improves cardiovascular function and reduces oxidative organ damage in the renal, cardiovascular and cerebral tissues of two-kidney, one-clip hypertensive rats

The putative protective effects of resveratrol against oxidative injury in the heart, kidney and brain tissues of rats induced with the two-kidney, one-clip (2K1C) hypertension model were investigated. Wistar albino rats were divided into sham-operated (n = 8) or 2K1C groups, in which rats received either resveratrol (10 mg/kg per day, i.p., n = 8), or saline (n = 8) starting at Week 3 after the surgery and continuing for the following 6 weeks. Indirect blood pressure recordings and echocardiographic images were made to evaluate cardiac function. At the end of Week 9 the animals were decapitated and plasma, heart, kidney and brain were taken for biochemical assays, while aortic rings were prepared for vascular reactivity studies. 2K1C hypertension resulted in increased blood pressure, aortic hypercontractility and reduced left ventricular function, leading to increased lipid peroxidation and myeloperoxidase activity, concomitant with significant reductions in tissue glutathione, superoxide dismutase, Na+/K+-ATPase and catalase activities in the cardiac, renal and brain tissues, indicating the presence of oxidative tissue damage in peripheral target organs. Elevated plasma levels of lactate dehydrogenase, creatine kinase, as well as reduced plasma levels of antioxidant capacity and nitric oxide further verified the severity of oxidative injury. A 6-week treatment with resveratrol reversed all the measured parameters, ameliorated hypertension-induced oxidative injury in the target organs and improved cardiovascular function. Resveratrol improved cardiovascular function through the augmentation of endogenous antioxidants and the inhibition of lipid peroxidation by maintaining a balance in oxidant/antioxidant status, which also ameliorated hypertension-induced oxidative injury in the cardiac, renal and cerebral tissues.

The Normal Difference in Bilateral Indirect Blood Pressure Recordings in Hypertensive Individuals

Abstract. Objective: If there is a significant dichotomy between bilateral systolic blood pressure determinations in both arms in hypertensive individuals, it is often taken as a sign of underlying pathology. The primary objective was to determine what the normal variation might be for a significant difference between blood pressures in both arms. A clinically significant difference was chosen as a systolic blood pressure value greater than 10 mm Hg between the upper extremities, as is commonly quoted at the bedside and in the literature. Methods: Bilateral indirect blood pressure determinations were obtained in 100 subjects with hypertension in the sitting position. The blood pressure was obtained by two observers, one the recorder and the other who obtained the blood pressure but was blinded to the actual values taken. The order of blood pressure determination in the first arm was determined prior to the study from a table of random numbers. The coefficient of variation in obtaining the blood pressure in each arm was determined in 5 of the 100 subjects. The age, sex, and handedness of each individual were recorded as demographic variables. Results: The average left and right systolic blood pressures were 139 ± 22 and 141 ± 22 mm Hg, respectively. The average left and right diastolic blood pressures were 78 ± 12 and 79 ± 13 mm Hg, respectively. There was no significant difference between left minus right systolic or diastolic differences (paired t‐test). There was no significant difference between systolic or diastolic blood pressures between gender or between left‐ and right‐handed individuals (nonpaired t‐test). The average coefficients of variation for taking right and left arm systolic pressures were 2.90% and 1.32%, respectively. Eighteen subjects (18%) had differences in systolic blood pressure between both arms exceeding 10 mm Hg (10% to 26%, 95% confidence interval). Conclusions: Differences of more than 10 mm Hg in indirect systolic blood pressure recordings between arms are frequent in asymptomatic hypertensive individuals and do not per se indicate any pathologic condition. In the right clinical situation, differences that are noted should be repeated and should be added to the total clinical picture when used to determine whether a pathologic condition is present. Assuming no significant aortic or subclavian disease in the population tested, the specificity of the bilateral blood pressure test was 82%.

The Normal Difference in Bilateral Indirect Blood Pressure Recordings in Normotensive Individuals

If there is a significant dichotomy between bilateral blood pressure determinations in both arms, it is often taken as a sign of some type of underlying pathology. We wished to evaluate what the normal variation might be for significant differences between blood pressures in both arms. Significant difference was arbitrarily chosen as a systolic blood pressure value greater than 10 mm Hg. Bilateral indirect blood pressure determinations were obtained in 100 subjects with no known history of hypertension in the sitting position. The blood pressure was obtained by 2 observers, one who recorded the systolic and diastolic blood pressure as announced by the person taking the blood pressures who was blinded to the actual values taken. The coefficient of variation in obtaining the blood pressures in each arm was determined in 5 of the 100 subjects. The age, sex, and handedness of each individual were recorded as demographic variables. The average left and right systolic blood pressures were 112.1 +/- 16.5 and 112.7 +/- 16.3 mm Hg, respectively. The average left and right diastolic pressures were 64.4 +/- 11.6 and 63.5 +/- 9.9 mm Hg, respectively. There was no significant difference between left minus right systolic or diastolic differences (Student's paired t-test). There were no significant differences in systolic or diastolic blood pressure between gender or between right and left handed individuals (non-paired t-test). The average coefficients of variation for right and left arm systolic blood pressures were 5.41% and 5.81%, respectively. Fifteen subjects had differences in systolic blood pressure between both arms exceeding 10 mm Hg (7% to 22%, 95% confidence interval). Differences of more than 10 mm Hg in indirect bilateral blood pressure recordings are frequent in normotensive individuals and probably do not per se indicate any abnormal pathology. In the right clinical situation, differences that are noted should probably be repeated and should be added to the total clinical picture when used to determine whether a pathologic condition is present.

Role of heating in non-invasive blood pressure measurements in rats.

The "tail-cuff" technique for indirect blood pressure measurements was standardized, with respect to heating, in experiments on 47 adult Sprague-Dawley rats. The direct, intra-arterial, and the indirect blood pressures were simultaneously obtained. Pulse volume was recorded from the tail by a non-invasive technique, and was controlled by gradual application of heat. It was found that pulse volume and body temperature were poorly related. A stable relation existed, however, between the error in the indirect blood pressure recordings and the pulse volume. The error was minimized, provided that the heating was adjusted to induce a pulse volume of at least 25% of the maximum obtainable value. It was suggested that the validity of the indirect blood pressure recording could be improved, if heat application was regulated on the basis of observations of pulse volume in the tail instead of ambient temperature or body temperature. Errors due to excessive vasoconstriction, or discomfort due to overheating could thereby be minimized.

Effects of blood pressure reduction on the structural vascular abnormality in skin and muscle vascular beds in human essential hypertension.

1. Vascular resistance at maximal vasodilatation was examined in two vascular beds in two groups of hypertensive patients and in normotensive control subjects before and during anti-hypertensive therapy in the hypertension groups. 2. In one group of twelve untreated patients with essential hypertension, examined with plethysmography and intra-arterial blood pressure recording, a significantly higher vascular resistance at maximal vasodilatation was found in the hands compared with normotensive control subjects matched for age, sex, weight and height. This indicated a structural vascular abnormality in the patient group. 3. After 5 years of anti-hypertensive therapy in the patient group the difference in vascular resistance between patients and control subjects had decreased significantly, indicating a reversibility of the structural vascular abnormality. 4. Vascular resistance at maximal vasodilatation was examined in the calves of twelve untreated patients with essential hypertension and fourteen normotensive control subjects. Plethysmographic technique and indirect blood pressure recordings were used. A significantly higher vascular resistance was found in patients than in control subjects, indicating a structural vascular abnormality also in this vascular bed. 5. Anti-hypertensive treatment for 6 months in the patient group did not change vascular resistance at maximal dilatation, indicating that the structural vascular abnormality remained. 6. During acute reduction of blood pressure in hypertension by means of trimethaphan infusion, blood pressure and blood flow to the hands were reduced proportionally with no change of vascular resistance at maximal vasodilatation. 7. This indicates that resistance at maximal dilatation was unaffected by the acute reduction of blood pressure, in contrast to the findings after prolonged reduction of blood pressure in this vascular bed.

SPHYGMOMANOMETRIC CUFF SIZE AND BLOOD PRESSURE RECORDINGS

In a group of 50 adult patients, indirect blood pressure recordings were obtained with nine Velcro self-adhesive cuffs of varying widths and lengths. Ten additional patients were studied to compare direct intraarterial blood pressure recordings with recordings obtained by the auscultatory method in the same arm. The data were subjected to statistical analyses that showed that the width of the air-inflatable bladder is important and should be 12 to 14 cm. The length of the bladder contained by the cuff needs only to encircle about one half the circumference of the arm. The standard adult arm cuff with a 23 × 12.5-cm bladder is adequate for accurate indirect blood pressure determinations in an adult population. The Velcro self-adhesive cuff is preferred because of its time saving qualities and smoother application.

Sphygmomanometric Cuff Size and Blood Pressure Recordings

In a group of 50 adult patients, indirect blood pressure recordings were obtained with nine Velcro self-adhesive cuffs of varying widths and lengths. Ten additional patients were studied to compare direct intraarterial blood pressure recordings with recordings obtained by the auscultatory method in the same arm. The data were subjected to statistical analyses that showed that the width of the air-inflatable bladder is important and should be 12 to 14 cm. The length of the bladder contained by the cuff needs only to encircle about one half the circumference of the arm. The standard adult arm cuff with a 23 × 12.5-cm bladder is adequate for accurate indirect blood pressure determinations in an adult population. The Velcro self-adhesive cuff is preferred because of its time saving qualities and smoother application.

Ultrasonic Indirect Blood Pressure Recordings in the Dog

Ultrasonic Indirect Blood Pressure Recordings in the Dog

Ultrasonic Indirect Blood Pressure Recordings in the Dog

Ultrasonic Indirect Blood Pressure Recordings in the Dog

Ultrasonic Indirect Blood Pressure Recordings in the Dog

Ultrasonic Indirect Blood Pressure Recordings in the Dog

Apgar score and neonatal blood pressure: A comparative study of obstetric methods in Sweden and in the United States

Obstetric techniques as applied to uncomplicated deliveries in a Swedish and an American hospital are described. A comparison by Apgar score is made of 200 American and 100 Swedish babies. At one minute, babies born in Sweden scored significantly higher than those born in America, but at 5 minutes this difference was no longer striking. The differences in techniques, including anesthesia, analgesia, barbiturate sedation, and instrumentation, and their relationship to the Apgar score are discussed. Serial indirect blood pressure recordings in 14 newborn infants whose mothers received general anesthesia and sedation are compared to 40 babies whose mothers received minimal anesthesia and sedation.