What preparations should be made before using tourniquet and hemostasis instrument?
1.使用前，要考虑病人情况、年龄、手术等因素，以选择长短、宽度适合的止血带；
1. Before use, the patient's condition, age, operation and other factors should be considered to select the tourniquet with suitable length and width;
2.尽可能选择较宽的止血带；
2. Choose a wide tourniquet as much as possible;
3.室温高或局部血供差者，止血仪使用时间宜相应缩短；
3. If the room temperature is high or the local blood supply is poor, the use time of the hemostat should be shortened accordingly;
4.手术时间超过 6 h，要逐步缩短充气时间，延长放气时间，使局部组织定时得到充分血液灌注；
4. If the operation time is more than 6 hours, it is necessary to gradually shorten the inflation time and extend the deflation time, so that the local tissue can be fully perfused regularly;
5.原则上，尽量缩短止血仪使用时间，以减少肢体缺氧时间和酸性物质的产生。
5. In principle, shorten the use time of hemostasis instrument as far as possible to reduce the time of limb hypoxia and the generation of acid substances.