Precautions for mass unreserved enema method. First, the temperature, concentration, flow rate, pressure and amount of solution should be mastered. Generally, the amount of solution for each enema should be about 500ml-800ml, and the pressure should be low, and low-pressure enemas are advocated. If the enema is for cooling, use isotonic saline at 28℃-32℃, keep it for 30 minutes and then discharge it, and record the body temperature half an hour after discharge. Patients in hepatic coma are contraindicated to use soapy water enemas, which can reduce the absorption of ammonia and reduce the effect of symptoms on the liver of patients in hepatic coma. During the enema, the patient’s vital signs should be observed at all times for changes in sellin pallor and sweating, severe abdominal pain, palpitations and panic, etc. If any of these conditions occur, the enema should be stopped immediately and the physician should be notified. Also pregnancy and acute abdomen and patients with gastrointestinal bleeding should not be treated with enemas.