Elevation of blood pressure

Hyperaldosteronism is accompanied by elevation of blood pressure (115), and can be treated with an aldosterone antagonist, eg, spironolactone (117) which... 

The amphetamines, such as amphetamine, dextroamphetamine (Dexedrine), and metliainphetainine (Desoxyn), are sympatiiomimetic (ie, adrenergic) dru that stimulate the CNS (see Chap. 22). Their drug action results in an elevation of blood pressure, wakefulness, and an increase or decrease in pulse rate The ability of these drugs to act as anorexiants and suppress the appetite is thought to be due to their action on the appetite center in the hypothalamus. 

Nitric oxide is a regulator of vascular smooth muscle blockage of its formation from arginine causes an acute elevation of blood pressure, indicating that regulation of blood pressure is one of its many functions. 

Rordorf G, Cramer SC, Efird JT, Schwamm LH, Buonanno F, Koroshetz WJ. Pharmacological elevation of blood pressure in acute stroke. Clinical effects and safety. Stroke 1997 28 2133-2138. 

Essential hypertension, whose prevalence is increased nearly two-fold in the diabetic population, may be another source of free-radical activity. The vascular lesions of hypertension can be produced by free-radical reactions (Selwign, 1983). In the recent Kuopio Ischaemic Heart Risk Factor Study in Finnish men, a marked elevation of blood pressure was associated with low levels of both plasma ascorbate and serum selenium (Salonen etal., 1988). A few studies report a hypotensive effect of supplementary ascorbate in patients with hypertension, but the actual changes in both systolic and diastolic pressure after ascorbate were not statistically significant in comparison with placebo (Trout, 1991). 

First described in the 1980s as "endothelium-derived relaxing factor," nitric oxide (NO) is a vasodilator believed to play a role in regulation of blood pressure under physiologic and pathophysiological conditions. For example, inhibition of NO synthesis under normal conditions and during septic shock results in a significant elevation of blood pressure. 

The possible involvement of free radicals in the development of hypertension has been suspected for a long time. In 1988, Salonen et al. [73] demonstrated the marked elevation of blood pressure for persons with the lowest levels of plasma ascorbic acid and serum selenium concentrations. In subsequent studies these authors confirmed their first observations and showed that the supplementation with antioxidant combination of ascorbic acid, selenium, vitamin E, and carotene resulted in a significant decrease in diastonic blood pressure [74] and enhanced the resistance of atherogenic lipoproteins in human plasma to oxidative stress [75]. Kristal et al. [76] demonstrated that hypertention is accompanied by priming of PMNs although the enhancement of superoxide release was not correlated with the levels of blood pressure. Russo et al. [77] showed that essential hypertension patients are characterized by higher MDA levels and decreased SOD activities. 

A 60-year-old male develops elevation of blood pressure, hyperglycemia., decreased bone density, and occult blood in his stool. Which of the following agents is associated with these adverse effects ... 

Sympathetic ganglia Pallor, occasional elevation of blood pressure. 

Norepinephrine is used for increasing cardiac constriction and for the necessary elevation of blood pressure after sharp decline, which can result from surgical intervention or trauma. Synonyms of noradrenaline are arterenol, levarterenol, levophed, and others. 

Fluid and electrolyte balance Average and large doses of hydrocortisone or cortisone can cause elevation of blood pressure, salt and water retention, and increased excretion of potassium. These effects are less likely to occur with the synthetic derivatives except when used in large doses. 

Adverse reactions may include palpitations tachycardia elevation of blood pressure reflex decrease in heart rate arrhythmias (at larger doses) overstimulation restlessness dizziness insomnia dyskinesia euphoria dysphoria tremor headache changes in libido dry mouth unpleasant taste diarrhea constipation urticaria impotence. 

Do not use dihydroergotamine with peripheral and central vasoconstrictors because the combination may result in additive or synergistic elevation of blood pressure. 

Overdose may induce ventricular extrasystoles and short paroxysms of ventricular tachycardia, a sensation of fullness in the head, and tingling of the extremities. Should an excessive elevation of blood pressure occur, it may be immediately relieved by an a-adrenergic blocking agent, e.g., phentolamine. 

Thus, the physician must establish with certainty that hypertension is persistent and requires treatment and must exclude secondary causes of hypertension that might be treated by definitive surgical procedures. Persistence of hypertension, particularly in persons with mild elevation of blood pressure, should be established by finding an elevated blood pressure on at least three different office visits. Ambulatory blood pressure monitoring may be the best predictor of risk and therefore of need for therapy in mild hypertension. Isolated systolic hypertension and hypertension in the elderly also benefit from therapy. 

Despite the large number of patients with chronic hypertension, hypertensive emergencies are relatively rare. Marked or sudden elevation of blood pressure may be a serious threat to life, however, and prompt control of blood pressure is indicated. Most frequently, hypertensive emergencies occur in patients whose hypertension is severe and poorly controlled and in those who suddenly discontinue antihypertensive medications. 

Mechanism of Action Fomis an active metabolite, desglymidodrine, an alpha, adrenergic-agonist. Activation of the arteriolar and venous vasculature, producing and increase in vascular tone and elevation of blood pressure. 

Arterial hypertension is very common. Approximately 40% of the population over the age of 40 exhibit elevations of blood pressure, more than 140 mm. of mercury systolic and 90 mm. diastolic (64). The incidence increases with advancing years. It appears to be greater in negroes (2, 3, 23), the obese (33), and those exposed to higher degrees of civilization (16). 

There is no dearth of chemical compounds that will cause a rise in blood pressure when injected into the experimental animal. Extracts of plant and animal tissues yield several, and enzymes present in the tissues will often produce pressor substances as a result of autolysis. For a chemical agent then to be proved as a cause of hypertension it must be found as such in the animal and in greater amount in the hypertensive than in the normal animal. The substance must be capable of producing a continued elevation of blood pressure when administered continuously to the normal animal. The substance must be of such a nature that the body does not make corrective or adaptive responses to it. In this fashion tachyphylaxis or immunological reactions may reduce the action of certain agents if given repeatedly. 

Physiologically, hypertension may be defined as an elevation of blood pressure above the normal limits of variability. There are at least five basic factors involved in the maintenance of blood pressure. Aberrations of any one or a combination of these factors could produce an elevation affecting principally systolic or diastolic pressure, or influencing both more or less equally. These factors include peripheral resistance, elasticity of the arteries, cardiac output (heart rate and stroke volume), blood volume, and viscosity of the blood. The central nervous system, the endocrine glands, and the kidney must exert their influence on blood pressure through the above factors. 

Although there may be no demonstrable alteration in the function of the cardiovascular system or the kidneys of such patients, other than the sustained elevation of blood pressure when they are at rest, the extreme responsiveness of these systems to emotional stress is remarkable. There may be no alteration of the inherent ability of an organ or tissue to respond to a stimulus. Instead, their greater reactivity is to an increased transmission of nerve impulses in response to what may be a psychogenic stimulus. Wolf, Pfeiffer, Ripley, Winter, and Wolff (166) have demonstrated such changes in their patients admirably, and two of their figures from a recent publication illustrate this point. 

Convincing as the preceding evidence may seem, there is just basis for a certain reservation concerning their significance. They tend to imply that the balance between the decarboxylation of pressor amine precursors and the elimination of the amines is so delicately maintained that an otherwise undetectable alteration in renal function would permit the formation of such amines to exceed their destruction or excretion, resulting in an elevation of blood pressure. There is evidence to the contrary that must be considered. 

MAOIs frequently are not the first choice when an antidepressant is needed. This is because their side effects include sedation, dizziness, insomnia, sexual dysfunction, rapid heartbeat, constipation, and agitation. Severe sudden elevation of blood pressure, especially when the patient eats aged meats and cheeses, or takes some over-the-counter cold medications, poses a serious threat of a stroke or other symptoms including headache, vomiting, and palpitations. 

HYPERTENSION Long-term elevation of blood pressure defined by two readings, systolic and diastolic blood pressure, respectively, that are above the normal of 140 and 90 mm Hg. Hypertension risks damage to the blood vessels, and complications, including stroke, heart attack, and kidney failure. 

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