Once a patient is admitted to the ICU, it means that the patient’s condition has reached a certain level of critical illness. Critical illness is when the patient’s organs, such as heart, brain, kidney, liver, etc., are endangered by infection or trauma and these organs become dysfunctional. Entering the ICU, on the one hand, requires effective monitoring of the organs. On the other hand, the function of each organ needs to be effectively supported, including the application of vasoactive drugs, ventilators, plasma exchange, artificial liver, bedside dialysis, etc., as well as the extensive use of antibiotics, the use of immune-enhancing drugs, and the improvement of the patient’s nutritional status in the ICU. The basic purpose is to make the patient recover as soon as possible. As a family member, we should prepare in two aspects: 1) communicate effectively with doctors and nurses, and fully understand the development of the disease; 2) once we have the opportunity to visit the patient, we should communicate effectively with the patient, and encourage the patient to strengthen functional exercise and rehabilitation as soon as possible, so as to get out of the ICU and recover life and health.