If a patient suddenly develops hypotension, there are the following causes: 1. Inadequate perfusion of blood, for example, when a patient has severe bleeding, trauma, or surgery, the patient will experience, for example, significant blood loss, and this will result in sudden hypotension. 2. In case of significant infection, for example, by bacteria, viruses, fungi or other pathogenic microorganisms, such as mycoplasma, chlamydia, etc., the patient will develop sepsis, and in severe cases, the patient will also develop septicemia. Sudden hypotension can also occur in severe cases of infectious shock. 3, primary endocrine metabolic diseases, such as hypothyroidism in patients with hypothyroid crisis, can also cause sudden hypotension. 4, cardiogenic factors, such as acute myocardial infarction or acute severe angina pectoris, some patients will also occur sudden hypotension.