Ketamine is the only intravenous anesthetic drug with sedative, analgesic and anesthetic effects, and the anesthetic signs of ketamine are different from those of traditional general anesthetics. Unlike other general anesthesia patients who are in a natural sleep-like state, when ketamine is injected alone, the patient is mute. After anesthesia, the patient’s eyes are open, and although various reflexes, such as corneal reflex, cough reflex, and gag reflex, still exist, there is no protective effect, and the patient loses memory of anesthesia and surgery, but the amnesic effect is not as obvious as that of benzodiazepines. The patient’s consciousness is completely lost, but his muscle tone is increased, and the patient’s eyes are staring or trembling, with the appearance of superficial anesthesia, but the analgesic effect is better, especially the effect of body surface analgesia, which has been described as dissociative anesthesia. Although ketamine has a good analgesic effect, it has a poor analgesic effect on internal organs. If the viscera are pulled during laparoscopy, the patient still reacts, some patients under anesthesia may show lacrimation or increased salivation, their neck and limb skeletal muscle tone may appear enhanced, and a few patients have symptoms of clenched teeth and involuntary movement of the extremities. Such anesthetic phenomena of indifferent expression, loss of consciousness, open eyes, deep analgesia and increased muscle tone are generally referred to as stubbornness or rigor mortis, and are characteristic of patients who choose ketamine anesthesia.