The most typical clinical symptom of capillary leakage syndrome is generalized tissue edema, which first appears in the subcutaneous tissue loosening, with the conjunctiva of the eye appearing at the earliest, then the face and neck edema, and only later the trunk and limbs appear, and gradually increase, accompanied by pleural fluid, ascites and pericardial fluid and other plasma cavity fluid; in severe cases, organ edema appears, and the function of edematous organs decreases. In severe cases, there is organ edema and decreased function of the edematous organs. Pulmonary edema with decreased diffusion and respiratory failure; myocardial edema with weakness of myocardial contraction; renal edema with difficulty in urination, etc. So how to diagnose? 1.Pre-leakage: This stage mainly refers to the process of massive blood transfusion and fluid transfusion in order to maintain circulatory stability in the early stage of trauma or shock rescue. The most important clinical characteristics of patients in this stage are insufficient effective blood volume and severe hypotension, and it is often difficult to maintain basic vital signs without rapid or large volume supplementation. 2. Leakage phase: Due to the change of capillary membrane permeability and obstruction of lymphatic reflux, a large amount of fluid is retained in the tissue interstitial space, thus making the lack of blood volume more serious. The clinical manifestations are continuously developing hypotension, decreased urine output, and generalized swelling that rapidly develops from the face, neck, and extremities to the trunk. In severe cases, it is often accompanied by signs of edema of the lungs, brain, and other organs. It may also be accompanied by pleural fluid, ascites, and pericardial effusion. The amount of mandatory extravascular fluid sequestration in the interstitial space is directly related to the severity of the disease, and fluid sequestration usually lasts more than 18 to 36 hours. The shorter the mandatory extravascular fluid sequestration period, the better the recovery, and vice versa, the worse the prognosis. 3. Recovery period: Due to the restoration of cell membrane potential and the rebuilding of sodium pump function, fluid returns from the interstitial space to the vascular space. Patients show a stabilization of circulation, only a small amount of fluid is needed to maintain blood pressure, pulse pressure increases, and urine output increases significantly. Some patients may experience transient symptoms of hypertension or cardiac or pulmonary insufficiency. With increased urine output, generalized edema gradually subsides over several days. Sometimes it takes up to about 10 days.