Norepinephrine administration

The net effect of norepinephrine administration on heart rate and ventricular contractile force therefore varies with the dose of norepinephrine, the physical activity of the subject, any prior cardiovascular and baroreceptor pathology, and the presence of other drugs that may alter reflexes. 

The vasoconstrictor actions of epinephrine and norepinephrine have been used to prolong the action of local anesthetics by reducing local blood flow in the region of the injection. Epinephrine has been used as a topical hemostatic agent for the control of local hemorrhage. Norepinephrine is infused intravenously to combat systemic hypotension during spinal anesthesia or other hypotensive conditions in which peripheral resistance is low, but it is not used to combat the hypotension due to most types of shock. In shock, marked sympathetic activity is already present, and perfusion of organs, such as the kidneys, may be jeopardized by norepinephrine administration. 

D. Administration of atropine prior to norepinephrine leads to an increase in heart rate after norepinephrine administration. 

Norepinephrine is a combined a- and S-agonist but maiifly produces vasoconstriction primarily via its more prominent a effects on all vascular beds, thus increasing SVR. Norepinephrine administration generally produces either no change or some increase in cardiac output. ... 

What would be the result of norepinephrine administration on a normotensive patient ... 

Explain the ramifications of norepinephrine administration in a severely hypotensive patient. 

Epinephrine has agonist activity at the (32 receptor, while norepinephrine does not. Therefore, norepinephrine administration results in a higher tension, provided both drugs are administered slowly, and at the same rate. 

Monoamine Oxidase Inhibitors. MAOIs inactivate the enzyme MAO, which is responsible for the oxidative deamination of a variety of endogenous and exogenous substances. Among the endogenous substances are the neurotransmitters, norepinephrine, dopamine, and serotonin. The prototype MAOI is iproniazid [54-92-2] (25), originally tested as an antitubercular dmg and a close chemical relative of the effective antitubercular, isoniazid [54-85-3] (26). Tubercular patients exhibited mood elevation, although no reHef of their tuberculosis, following chronic administration of iproniazid. In... 

Amphetamine administration produces a marked increase in cortical dopamine, norepinephrine, and... 

MAINTAINING ADEQUATE TISSUE PERFUSION. When a patient is in shock and experiencing ineffective tissue perfusion tiiere is a decrease in oxygen resulting in an inability of die body to nourish its cells at die capillary level. If die patient has marked hypotension die administration of a vasopressor (a drug diat raises die blood pressure because of its ability to constrict blood vessels) is required. The primary health care provider determines die cause of die hypotension and then selects the best mediod of treatment. Some hypotensive episodes require die use of a less potent vasopressor, such as metaraminol, whereas at other times a more potent vasopressor, such as dobutamine (Dobutrex), dopamine (Intropin), or norepinephrine (Levoplied) is necessary. 

The less potent vasopressors, such as metaraminol, also require close patient supervision during administration. The nurse follows the same procedure as that for norepinephrine and dopamine but may take blood pressure and pulse determinations at less frequent intervals, usually every 15 to 30 minutes. The nurse needs sound clinical judgment to detemrine the frequency because there is no absolute minimum or maximum time limit between detenninations. 

Some drugs such as norepinephrine or dopamine are particularly damaging to the surrounding tissues if extravasation (infiltration) occurs during intravenous administration. Hientolamine is used to prevent or treat tissue damage caused by extravasation of these dru. ... 

The answer is a. (Hardman, p 224.) Epinephrine is the drug of choice to relieve the symptoms of an acute, systemic, immediate hypersensitivity reaction to an allergen (anaphylactic shock). Subcutaneous administration of a 1 1000 solution of epinephrine rapidly relieves itching and urticaria, and this may save the life of the patient when laryngeal edema and bronchospasm threaten suffocation and severe hypotension and cardiac arrhythmias become life-endangering. Norepinephrine, isoproterenol, and atropine are ineffective therapies Angioedema is responsive to antihis-... 

Howe, J. R., and Yaksh, T. L. (1982) Changes in sensitivity to intrathecal norepinephrine and serotonin after 6-hydroxydopamine (6-OHDA), 5,6-dihydroxytryptamine (5,6-DHT) or repeated monoamine administration. J. Pharmacol. Exp. Ther., 220 311-321. 

Inhibition of norepinephrine biosynthesis can be achieved quite well by chronic oral administration of the tyrosine hydroxylase inhibitor CH-methyl-p-tyrosine (LXII) but reduction in blood pressure was not achieved in patients with essential hypertension (77). Another potent inhibitor, 3-iodotyrosine (LXIII) was also inactive in man (78). Apparently, substantial reduction of norepinephrine (50-70%) is not enough to achieve the desired effect. 

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