Hypotension INDEX

Invasive hemodynamic monitoring should be considered in patients who are refractory to initial therapy, whose volume status is unclear, or who have clinically significant hypotension such as systolic BP <80 mm Hg. Such monitoring helps guide treatment and classify patients into four specific hemodynamic subsets based on cardiac index and pulmonary artery occlusion pressure (PAOP). Refer to textbook Chap. 16 (Heart Failure) for more information. 

Pildralazine (65), when administered i.v. or orally, displays a high antihypertensive activity in conscious hypertensive animals (rats, dogs). The hypotensive effect, caused by oral doses of 0.1 mg/kg to 1 mg/kg, has been reported to last more than 24 h. The therapeutic index (LD50/ED25 rats oral administration) has been found to be 70-times higher than that of hydralazine due to both higher potency and reduced toxicity [197]. It has been concluded that (65), like hydralazine, acts on peripheral smooth muscle on specific receptors which are physiologically affected by ATP released from... 

Monoamine oxidase inhibitors have a low therapeutic index. Adverse effects include orthostatic hypotension, impotence and insomnia. Overdoses become manifest by symptoms of agitation, hyper-reflexia followed by convulsions. Rare but serious cases of hepatotoxicity have been associated with the use of isocarboxazid and of phenelzine. 

It is characterized by severe, persisting pain, shock and hypotension with possible development of arrhythmias and is due to severe depression of systolic cardiac performance, systolic arterial pressure is below 80 mm Hg, low cardiac index, ventricular filling pressure is elevated and pulmonary edema may or may not be evident. The most frequent cause is infarction involving more than fourty percent of the left ventricular myocardiam, leading to a severe reduction in left ventricular contractility contradictively and failure of the left ventricular pump. 

It has also been suggested that terlipressin has vasoconstrictor activity within the splanchnic vascular territory (21). Hypotension developed under general anesthesia in 32 patients undergoing carotid endarterectomy treated with renin-angiotensin inhibitors (22). They were randomized to received terlipressin 1 mg (n = 16) or noradrenaline infusion. Compared with baseline those who received terlipressin had reduced gastric mucosal perfusion for at least 4 hours. There was also reduced oxygen delivery and oxygen consumption index at 30 minutes and 4 hours in those who received terlipressin. 

Increase by 0.05 increments patch bradycardia, hypotension, rebound hyperten- index OD-bradycardia, decreased treatment of ADHD... 

Clonidine is one of the most widely used sedating medications in pediatric and child psychiatry practice, particularly in children with sleep onset delay and ADHD. It is a central alpha2 agonist. Pharmacokinetics show rapid absorption, with an onset action within 1 h, peak effects at 2-4 h and a half-life 6-24 h. Effects on sleep architecture are fairly minimal but may include decreased REM, so that discontinuation can lead to REM rebound. Clonidine has a narrow therapeutic index, and there has been a recent dramatic increase in reports of overdose with this medication. Potentially significant side effects including hypotension, bradycardia, anticholinergic effects, irritability, and dysphoria rebound hypertension may occur on abrupt discontinuation. Tolerance often develops, necessitating increases in dose. 

Abdel Salam AR, Drummond GB, Bauld HW, Scott DB. Clearance of indocyanine green as an index of liver function during cyclopropane anaesthesia and induced hypotension. Br J Anaesth 1976 48(3) 231-8. 

Vasopressin is emerging as a potentially useful therapy in the hemodynamic support of vasodilatory septic shock. Case series and small clinical trials have reported its use in patients who remain hypotensive on vasopressors. Arginine vasopressin has little pressor activity in normal subjects but markedly increases blood pressure when sympathetic nerve function is impaired, including in septic shock. Unlike the catecholamine vasopressors, vasopressin is a direct vasoconstrictor agent and does not have inotropic or chronotropic effects. As a result, it may decrease cardiac output and hepatosplanchnic flow. In fact, studies of vasopressin in septic shock generally do not enroll patients with a cardiac index of less than 2 to 2.5 L/m per minute. 

A decrease in PaC02 may occur in patients with cardiogenic, hypovolemic, or septic shock because oxygen delivery to the carotid and aortic chemoreceptors is reduced. This relative deficit in Pa02 stimulates an increase in ventilation. The hyperventilation in sepsis is also mediated via a central mechanism. Hyperventilation-induced respiratory alkalosis with an elevation in cardiac index and hypotension without peripheral vasoconstriction may therefore be an early sign of sepsis. 

Agents commonly considered for vasopressor or inotropic support include dopamine, dobutamine, norepinephrine, phenylephrine, and epinephrine (Table 117 ). Dopamine, an a- and -adrenergic agent with dopaminergic activity, appears to increase MAP effectively in patients who remain hypotensive with reduced cardiac function after aggressive fluid resuscitation. Thus it is often the initial choice in sepsis because of combined vasopressor and inotropic effects. While low-dose dopamine (1 to 5 mcg/kg per minute) is effective in maintaining renal perfnsion, higher doses (>5 mcg/kg per minute) exhibit a and f) activity and are used frequently to support blood pressure and to improve cardiac function such as an increase in cardiac index (Cl). 

Class Index C22 Grayanotoxins CAS — hypotensive action. leaves of various species of Rhododendrons. Grayanotoxins are crystalline materials that are soluble in hot water and alcohols. 

Effects on the myocardium are not significant in normal individuals. In patients with coronary artery disease but no acute medical problems, 8-15 mg morphine administered intravenously produces a decrease in oxygen consumption, left ventricular end-diastolic pressure, and cardiac work effects on cardiac index usually are slight. In patients with acute myocardial infarction, the cardiovascular responses to morphine may be more variable than in normal subjects, and hypotension may be more pronounced. 

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