Abstract: The aim of analgesia and sedation treatment is to protect the morphology and functional reserve of organs. On the basis of circulatory perfusion and oxygenation, which can meet the minimum requirement of body and organ metabolism in the whole body, the organs can be rest and function harmoniously, so as to save and protect the organ’s reserve function to the maximum extent, so that the critically ill patients can maintain good living quality as much as possible after the rehabilitation. It will be very important for the sustainable development of critical care medicine. In the process of achieving the purpose of analgesic and sedative therapy, it is necessary to set up different analgesic sedative targets according to the patient’s condition, basic state and organ function. It is not suitable to simply and mechanically emphasize "deep sedation" or "light sedation". Analgesic and sedative treatment is a double-edged sword. No monitoring, no analgesia and sedation. To give the optimal analgesia and sedation therapy, it requires continuous monitoring and evaluation of whether the treatment is in order to achieve analgesic and sedative targets and to reach the purpose of protecting organ function. However, the monitoring and evaluation should not only be limited to the understanding of pain and consciousness and cognition, but also the dynamic changes in the basic vital signs of patients. By means of monitoring and evaluation, we can achieve the goal of keeping all organs of the body alive, preserving function as much as possible, reducing chronic and critical illness and improving the quality of life in patients.

Key words: analgesia, hypnotics and sedatives, multiple organ failure, critical illness, quality of life