Management of perioperative hypertension using intravenous isradipine

Calcium Antagonists for Perioperative Blood Pressure Control

Calcium entry blockers constitute three major classes of pharmacologic agents: phenylalkylamines (eg, verapa mil), benzothiazepines (eg, diltiazem), and dihydropyri dines (eg, nifedipine). The effectiveness of all types of calcium channel blockers in the prevention and treat ment of coronary artery disease as well as chronic and acute hypertension is undisputable. Their beneficial clinical effects may be due to peripheral and coronary vasodilatation, resulting in reduction in myocardial oxy gen consumption, and an increase in myocardial oxy gen supply in addition to their antispasmodic effect and the ability to prevent intracellular calcium overload. For the management of perioperative hypertension develop ing in patients undergoing cardiac or noncardiac sur gery, the dihydropyridines appear to be especially suit able. Intravenous (IV) formulations of nifedipine, nicardipine, and isradipine have been successfully used in this setting. At the present time, nicardipine is the most widely used IV dihydropyridine. This is due to its potent afterload-reducing activity and relatively short duration of action, although its effect may increase the longer the drug is being infused. The ideal drug for perioperative blood pressure control should be one with the pharmacodynamic profile of the vascular selec tive dihydropyridines, but with an ultrashort duration of action.

Assessment and nursing management of hypertension in the perioperative period

Over 50 million persons in the United States have hypertension, making it one of the most common abnormalities found in the perioperative patient. Often discovered during the preoperative assessment of the patient scheduled for surgery, hypertension raises many concerns in the perioperative period, including hemodynamic control during anesthesia, postoperative complications, and the risk of comorbidities that may not be evident until the patient is stressed. This article concentrates on the identification of hypertension preoperatively, the potential problems associated with hypertension in the entire perioperative period, and pharmacologic and nursing management.

Role of isradipine and other antihypertensive agents in the treatment of peri- and postoperative hypertension

The traditional therapy of perioperative hypertension is now being challenged by the availability of new agents. Vasodilator therapy should be the first-line choice, although dihydropyridine calcium antagonists, particularly isradipine, appear to be suitable in this setting because of their pharmacological properties. Because of its ultrashort half-life, sodium nitroprusside has to be administered by continuous infusion, even for the treatment of an acute elevation of blood pressure. This is not the case with the new agents that have longer durations of action. A bolus administration is sufficient for the correction of most elevations of arterial pressure that are due to transient adrenergic activation. Continuous infusion is required only in patients who have sustained increases of systemic vascular resistance; these are usually patients who are already hypertensive.