The main effects and functions of sodium nitroprusside are as follows: 1. It can be used to treat various diseases, such as acute progressive hypertension, hypertensive encephalopathy, and hypertension combined with aortic dissection, etc., resulting in hypertensive emergencies, and also suitable for sudden increase in blood pressure after surgery, can be treated with sodium nitroprusside. 2. For hypertension combined by acute left heart failure, pulmonary edema, etc., the disease requires early application of sodium nitroprusside. 3. The intractable refractory heart failure caused by this drug can be treated with this drug, the course of treatment can be maintained for several weeks or even longer. 4, mitral valve and aortic valve closure insufficiency, ventricular septal defect, etc., its can make the blood flow regurgitation to reduce, for use before surgery. The mechanism of action of sodium nitroprusside is mainly due to its ability to dilate resistance vessels and volume vessels, thus achieving a reduction in left ventricular filling pressure and an increase in cardiac output.