Despite great advances in medical technology, postoperative nausea and vomiting (PONV) is still a common postoperative complication, with a reported average incidence of 20% to 30%. In high-risk patients even up to 70%. In addition to bringing serious discomfort to patients, nausea and vomiting may also cause medical complications, such as wound dehiscence, bleeding, aspiration pneumonia, water-electrolyte disorders, etc. Therefore, although PONV may be a small medical problem, but for the patient may be a big trouble! So the prevention and control methods for PONV is increasingly being paid attention to. First, the risk factors of PONV. 1, patient factors gender is one of the main factors affecting the incidence of PONV. The incidence of women is more than 3 times that of men. This phenomenon may be due to different levels of hormones. Non-smokers have a higher risk of PONV than smokers. Have a history of PONV or motion sickness history of patients PONV incidence will increase 2 to 3 times. The relationship between age and PONV is complex, and there are still different opinions. There are studies that young people are prone to PONV, 50 years of age or older patients PONV incidence decreases, the age of every 10 years, the incidence of 13% decrease. However, there are studies that age is not the main factor affecting the incidence of PONV. Recent studies have shown that the difference in genotype is one of the important factors in determining whether patients are at high risk of PONV. 2, narcotic factors opioid analgesics is also one of the factors that cause PONV. These drugs can directly act on the brain vomiting center, increase vestibular organ sensitivity, reduce the ability of gastrointestinal motility. Analgesia in combination with regional nerve blocks and other kinds of analgesics such as non-steroidal anti-inflammatory drugs, can reduce the amount of opioid analgesics, thereby reducing the occurrence of PONV. It has been clear that inhaling human anesthetics can significantly increase the incidence of PONV. Therefore, for the high-risk group of PONV should be considered to avoid the use of inhaled anesthetics. The antagonist of the muscle relaxant neostigmine at higher doses (>2.5 mg) will also increase the incidence of PONV. In recent years, the application of increasingly common intravenous anesthetics isoproterenol to reduce the incidence of PONV advantages have been gradually discovered. In contrast, other intravenous anesthetics such as thiopental sodium, etomidate, ketamine have a higher incidence of PONV than isoproterenol. Anesthesia causes PONV, in addition to anesthetic drugs, but also with the use of mask oxygen during anesthesia resulting in gas into the gastrointestinal cavity so that the expansion, flatulence and other related. 3, surgical factors with the prolongation of surgery, the incidence of PONV also increased accordingly, may be related to the accumulation of anesthetic drugs that cause vomiting. The type of surgery and the way also has a relationship with the occurrence of PONV, such as head and facial plastic surgery, eye, ear, nose and throat oral surgery, gynecological surgery, abdominal surgery and laparoscopic surgery, the incidence of PONV are relatively high. Second, drug prevention and treatment currently used to prevent and treat PONV drugs are many, mainly the following three categories: 1, 5hydroxytryptamine 3 (5HT3) receptor antagonists such as ondansetron, granisetron, toltesetron, ramosetron, etc., the chemical structure of such drugs are similar, the efficacy and side effects are similar. Common side effects are: headache, dizziness, constipation, diarrhea, which are usually mild and easy to manage. Hemodynamic changes and extrapyramidal reactions are rare. Electrocardiographic changes such as QT interval prolongation, although occasionally appear, but no clinical significance. The effect of these drugs to prevent and treat PONV are better, the clinical application is gradually increasing. 2, traditional anti-emetic drugs including butylphenols, benzamide, phenothiazines, antihistamines, anticholinergic drugs, currently more application of haloperidol and metoclopramide, the latter is generally used only for the treatment of vomiting after the occurrence of haloperidol prophylaxis also has a good effect. 3, other drugs such as dexamethasone, preoperative dosing to prevent PONV is better than the effect of postoperative dosing. After the occurrence of vomiting with dexamethasone treatment but not effective. Prevention and treatment of PONV involves many aspects, such as reducing the risk factors in anesthesia, drug and non-drug prevention and treatment. Risk assessment of patients and according to the assessment results of the preventive application of anti-emetic drugs can reduce the occurrence of PONV. To prevent the failure of patients can apply a variety of methods to treat PONV, should clarify the previous anti-emetic drugs and drug duration of action, the choice of different kinds of drugs better results.