Pulmonary thromboembolism is an acute and serious critical illness, which is caused by embolism due to intrapulmonary thrombus, resulting in ischemia and hypoxia in the corresponding lung tissues leading to respiratory failure, and the cure rate is about 60%. The cure rate is about 60%. It can be achieved by early diagnosis, early anticoagulation and thrombolysis, and maintenance of stable vital signs to prevent cardiopulmonary failure. However, if the diagnosis and treatment are not carried out in time and the treatment time is delayed, pulmonary failure, cardiac failure, and even multi-system organ failure and death are likely to occur, and the mortality rate can reach about 25%.