To do liposuction, general anesthesia must be done first, and the liposuction part should be cut about 0. 5 to 1. 0 cm wound, then insert the catheter directly into the bottom layer of fat accumulation, and then use a vacuum compressor to extract excess fat. This surgical method is called "dry pumping". Another method is to inject water and drugs after anesthesia, so that the fat cells at the liposuction site swell up, and then insert a straw for liposuction. This method is called "wet liposuction". The average adult can bear 500 ml of blood loss. Therefore, the traditional vacuum suction liposuction method only needs more than 4000ml； at a time; Ultrasonic liposuction does not exceed 10000 ml at a time, which is equivalent to 10 kg of fat, which belongs to the safe range.

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