Peripheral vasodilator

A drug that has the effect of dilating peripheral blood vessels. Also known as peripheral vasodilators (peripheral vasodilators). There are many types of vasodilators that have been used clinically so far, and can be classified into two categories. One class is drugs that directly relax vascular smooth muscle, namely direct vasodilators such as hydralazine, sodium nitroprusside and nitrates; the other is drugs that ultimately cause vasodilatation through different mechanisms of action, including alpha-adrenal glands. Receptor blockers, calcium antagonists and angiotensin converting enzyme inhibitors. In addition to traditionally used to treat a variety of cardiovascular diseases such as hypertension, they are currently used to treat acute and chronic cardiac insufficiency. This is based on the ability of such drugs to dilate small veins, reduce blood flow to the heart, reduce ventricular filling pressure and reduce cardiac preload; dilate small arteries, reduce peripheral vascular resistance, reduce ventricular ejection resistance and reduce cardiac afterload; It can reduce the ventricular muscle tension and improve the beneficial effects of myocardial oxygen supply and demand balance. Therefore, acute left heart failure and pulmonary edema after myocardial infarction, hypertensive heart disease or open heart surgery can be significantly treated with vasodilators, for chronic congestive heart failure, especially for digitalis poisoning or with foreign Rehmannia and diuretic treatment do not respond to refractory heart failure also have considerable relief. Clinical practice has shown that at the appropriate dose of vasodilator, the arterial blood pressure is unchanged or slightly decreased, and the heart rate does not change much. However, if the dose is too large, it can cause severe hypotension. Therefore, the application should start with a small dose, and closely monitor the heart rate and blood pressure, and conditionally monitor the pulmonary capillary wedge pressure. Long-term application can not immediately stop the drug, otherwise it will cause rebound.