It is often seen that patients with reduced pulmonary wedge pressure (pcwp) find hemorrhagic shock in their lives, so we have to master some shock prevention methods, and I think we all know that shock is a common acute syndrome. In this state, the effective blood flow of the whole body is reduced and the microcirculation is impaired, leading to ischemia and hypoxia of important vital organs. This is also extremely dangerous, so let’s look at how to prevent the patient’s pulmonary artery wedge pressure (pcwp) decreased? 1, the possibility of hemorrhagic shock of the injured patients, should be for the cause, take the appropriate preventive measures, active hemorrhage to, the exact hemostasis; fracture site to be securely fixed; soft tissue injuries should be bandaged to prevent contamination; respiratory obstruction need to perform tracheotomy; need to evacuate, should strive to occur before and after the shock sent, and choose a fast and comfortable means of transport. When transporting the patient’s head to the rear of the car or the tail of the plane, to prevent cerebral anemia during travel. On the way to evacuation, we should continue to infuse fluids and be prepared for emergency treatment. 2, patients with serious infections, the use of sensitive antibiotics, intravenous drip, and actively remove the primary lesion (such as drainage of pus drainage, etc.). For certain surgical diseases that may be complicated by shock, grasp the preoperative preparation and perform surgical treatment within 2 hours, such as necrotic intestinal segment removal. 3. The preoperative preparation of surgical patients must be fully done, including correction of water and electrolyte disorders and hypoproteinemia; replenishment of blood volume; comprehensive understanding of visceral function; and selection of appropriate anesthesia methods. It is also necessary to fully estimate the various factors that may occur intraoperative hemorrhagic shock, and take corresponding measures to prevent hypovolemic shock. 4, mild dizziness, can be assisted to walk for a certain period of time, the discomfort will disappear. Slightly heavy without the ability to walk, let the patient lie flat, collar loose, head slightly lowered, and then raise the patient’s lower limbs for a slight shaking, hemorrhagic shock patients immediately get relief. 5, it must be noted that regardless of the degree of shock, do not give the patient any drinks or medication in the first aid, to wait until they are awake before they drink some warm water, and especially remind the patient to pay attention to warmth and rest.