***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Background It is commonly stated that risk factors for postoperative nausea are the same as for vomiting . The authors design ed a prospect i ve study to identify and differentiate the risk factors for postoperative nausea and vomiting in various surgical population s in a clinical audit setting . Methods The study included 671 consecutive surgical in patients , aged 15 yr or more , undergoing various procedures . The study focused on postoperative  nausea visual analog scale scores every 4 h and vomiting episodes within 72 h. Both vomiting and retching were considered as emetic events . Patient- , anesthesia- , and surgery-related variables that were considered to have a possible effect on the proportion of patients experiencing postoperative nausea and /or vomiting were examined . The bivariate Dale model for binary correlated outcomes was used to identify selectively the potential risk factors of postoperative nausea and vomiting . Results Among the 671 patients in the study , 126 ( 19 % ) reported one or more episodes of nausea , and 66 patients ( 10 % ) suffered one or more emetic episodes during the studied period . There was a highly significant association between the two outcomes . Some risk factors were predictive of both nausea and vomiting ( female gender , nonsmoking status , and general anesthesia ) . History of migraine and type of surgery were mainly responsible for nausea but not for vomiting . The predictive effect of risk factors was controlled for postoperative pain and analgesic drugs . Conclusion This study shows that differences exist in risk factors of postoperative nausea and vomiting . These could be explained by differences in the physiopathology of the two symptoms Background The safety and antiemetic efficacy of CP-122,721 , a novel neurokinin-1 antagonist , was evaluated when administered alone or in combination with ondansetron . Methods Using a r and omized , double-blind , placebo-controlled study design , CP-122,721 was initially compared with placebo and subsequently to ondansetron alone and in combination for prophylaxis against postoperative nausea and vomiting in 243 women undergoing abdominal hysterectomy . In the dose-ranging studies ( n = 86 ) , patients received either CP-122,721 100 mg ( vs. placebo ) or 200 mg ( vs. placebo ) orally 60–90 min before induction of anesthesia . In the interaction study ( n = 157 ) , patients received CP-122,721 200 mg or placebo 60–90 min before induction of anesthesia , and ondansetron 4 mg or saline 2 ml intravenously 15–30 min before the end of surgery . Patients assessed their level of nausea and pain on arrival in the postanesthesia care unit and at 0.5- , 1- , 1.5- , 2- , 4- , 8- , 12- , and 24-h intervals postoperatively . Emetic episodes , need for rescue antiemetic – antinausea medication , postoperative complications , and patient satisfaction were recorded . Results In the initial dose-ranging study , only 10 % of the patients experienced emesis within the first 8 h after surgery with CP-122,721 200 mg compared with 50 % in the placebo group . CP-122,721 200 mg also decreased the need for rescue medication ( 25%vs . 48 % ) . CP-122,721 100 mg was less effective than 200 mg in decreasing the incidence of repeated episodes of emesis . In the interaction study , 6 % of the patients receiving CP-122,721 200 mg orally experienced emesis less than 2 h after surgery compared with 17 % with ondansetron alone . With combined therapy , only 2 % experienced emesis . In addition , the median times for 75 % of patients to remain free from postoperative nausea and vomiting were 82 , 75 , and 362 min in the ondansetron , CP-122,721 , and combination groups , respectively . Conclusions Oral CP-122,721 200 mg decreased emetic episodes compared with ondansetron ( 4 mg intravenously ) during the first 24 h after gynecologic surgery ; however , there was no difference in patient satisfaction Supplemental 80 % oxygen administration halves the incidence of postoperative nausea and vomiting ( PONV ) in in patients . Whether it prevents PONV after ambulatory surgery is unknown . We tested the efficacy of supplemental 80 % oxygen in decreasing the incidence of PONV after ambulatory gynecologic laparoscopy . One hundred patients were given a st and ardized sevoflurane anesthetic .  They were r and omly assigned to two groups : routine oxygen administration with 30 % oxygen , balance nitrogen ( Group A ) ; and supplemental oxygen with 80 % oxygen , balance nitrogen ( Group B ) . Oxygen was administered during surgery and up to 1 h after surgery . The incidence of nausea and vomiting and the need for rescue antiemetics did not differ between the groups in the postanesthesia care unit , in the Phase II unit , or during the 24-h follow-up . The overall incidence of nausea and vomiting during the first postoperative 24 h was 62 % in Group A and 55 % in Group B ( P = 0.486 ) . There were no differences in the recovery profiles and patient satisfaction between the groups . In this study , supplemental oxygen did not prevent PONV in patients undergoing ambulatory gynecologic laparoscopy Postoperative nausea , a common complication in patients receiving general anesthesia , was studied in this r and omized investigation to compare the efficacy of 70 % inhaled isopropyl alcohol and intravenous ondansetron . For the study , 100 healthy women , ASA physical status I or II , scheduled for outpatient gynecologic laparoscopic procedures r and omly received 4 mg of intravenous ondansetron or isopropyl alcohol for the treatment of postoperative nausea . Nausea was measured on arrival to the postanesthesia care unit , at first complaint of nausea , every 5 minutes after initiation of therapy until nausea resolution , and every 15 minutes thereafter using a 0 to 10 verbal numerical rating scale . At 5 , 10 , and 15 minutes , the median verbal numerical rating scores between the ondansetron and alcohol groups were 6.00 and 3.00 , 5.00 and 3.00 , and 5.00 and 2.00 , respectively ( P = .002 , .015 , and .036 , respectively ) . No statistically significant differences were found at any other time interval . Mean times from initiation of therapy to a 50 % reduction in nausea between the ondansetron and alcohol groups were 6.3 minutes and 27.7 minutes , respectively ( P = 0.022 ) . Based on this study , it seems postoperative nausea can be resolved quicker using 70 % inhaled isopropyl alcohol compared with intravenous ondansetron in women undergoing outpatient gynecologic laparoscopic procedures Background : The aim of this study was to identify factors most relevant for postoperative vomiting ( PV ) and to develop a risk score to predict the probability of PV In this double-blind , r and omized , parallel group study , we have investigated the antiemetic activity of the potent and selective NK1 receptor antagonist GR205171 25 mg i.v . compared with placebo in the treatment of established postoperative nausea and vomiting ( PONV ) in patients after major gynaecological surgery performed under general anaesthesia . The incidence of PONV in the study population was 65 % . Thirty-six patients were treated with placebo  or GR205171 ( 18 patients per group ) . GR205171 produced greater control of PONV than placebo over the 24-h assessment period . The stimuli for emesis after PONV are multifactorial and the efficacy of GR205171 in this study supports the broad spectrum potential for NK1 receptor antagonists in the management of postoperative emesis .  GR205171 was well tolerated and no adverse events were reported that would preclude the further development of this agent BACKGROUND Iletrospective studies fail to identify predictors of postoperative nausea and vomiting ( PONV ) . The authors prospect ively studied 17,638 consecutive out patients who had surgery to identify predictors . METHODS Data on medical conditions , anesthesia , surgery , and PONV were collected in the post-anesthesia care unit , in the ambulatory surgical unit , and in telephone interviews conducted 24 h after surgery . Multiple logistic regression with backward stepwise elimination was used to develop a predictive model An independent set of patients was used to vali date the model RESULTS Age ( younger or older ) , sex ( female or male ) , smoking status ( nonsmokers or smokers ) , previous PONV , type of anesthesia ( general or other ) , duration of anesthesia ( longer or shorter ) , and type of surgery ( plastic , orthopedic shoulder , or other ) were independent predictors of PONV . A 10-yr increase in age decreased the likelihood of PONV by 13 % . The risk for men was one third that for women . A 30-min increase in the duration of anesthesia increased the likelihood of PONV by 59 % . General anesthesia increased the likelihood of PONV 11 times compared with other types of anesthesia . Patients with plastic and orthopedic shoulder surgery had a sixfold increase in the risk for PONV . The model predicted PONV accurately and yielded an area under the receiver operating characteristic curve of 0.785+/-0.011 using an independent validation set . CONCLUSIONS A vali date d mathematical model is provided to calculate the risk of PONV in out patients having surgery . Knowing the factors that predict PONV will help anesthesiologists determine which patients will need antiemetic therapy Background : At dosages above 0.1 mg/kg , droperidol inducesa dose-dependent QTc interval prolongation . Although subject to controversy , low-dose droperidol has recently been suspected to induce cardiac arrhythmias . Hence , 5-hydroxytryptamine type 3 antagonists have become the first-line drug for management of postoperative nausea and vomiting . These drugs are also known to prolong the QTc interval at high dosages . This study describes QTc interval changes associated with postoperative nausea and vomiting treatment by droperidol or ondansetron at low doses . Methods : Eighty-five patients with postoperative nausea and vomiting were included in this prospect i ve , single-blind study . Patients received either 0.75 mg intravenous droperidol ( n = 43 ) or 4 mg intravenous ondansetron ( n = 42 ) .  Electrocardiographic recordings were obtained before administration of antiemetic drug and then 1 , 2 , 3 , 5 , 10 , and 15 min after . Electrocardiographic monitoring was maintained for 3 h in eight patients in each group . Results : The QTc interval was prolonged ( > 450 ms in men , > 470 ms in women ) in 21 % of the patients before antiemetic drug administration . This was significantly correlated with lower body temperature and longer duration of anesthesia . Compared with predrug QTc measurement , both antiemetics were associated with a significant QTc interval prolongation ( P < 0.0001 ) . The mean maximal QTc interval prolongation was 17 ± 9 ms after droperidol occurring at the second minute and 20 ± 13 ms after ondansetron at the third minute ( both P < 0.0001 ) . Compared with predrug measurement , the QTc interval was significantly lower after the 90th minute in both groups . Conclusions : Droperidol and ondansetron induced similar clinical ly relevant QTc interval prolongations . When used in treatment of postoperative nausea and vomiting , a situation where prolongation of the QTc interval seems to occur , the safety of 5-hydroxytryptamine type 3 antagonists may not be superior to that of low-dose droperidol BACKGROUND Supplemental intra-operative oxygen 80 % halves the incidence of nausea and vomiting after open and laparoscopic abdominal surgery , perhaps by ameliorating intestinal ischaemia associated with abdominal surgery . It is unlikely that thyroid surgery compromises intestinal perfusion . We therefore tested the hypothesis that supplemental perioperative oxygen does not reduce the risk of postoperative nausea and vomiting ( PONV ) after thyroidectomy . METHODS One hundred and fifty patients undergoing thyroidectomy were given  sevoflurane anaesthesia . After induction , patients were r and omly assigned to the following treatments : ( i ) . 30 % oxygen , ( ii ) . 80 % oxygen , or ( iii ) . 30 % oxygen with droperidol 0.625 mg . RESULTS The overall incidence of nausea during the first 24 h after surgery was 48 % in the patients given oxygen 30 % , 46 % in those given oxygen 80 % , and 22 % in those given droperidol ( P=0.004 ) . There were no significant differences between the oxygen 30 % and 80 % groups in incidence or severity of PONV , the need for rescue antiemetics , or patient satisfaction .  
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Use of clinical practice guidelines , however , has been shown to positively affect clinical practice and patient outcomes across a wide variety of specialties