Evaluation of three risk scores to predict postoperative nausea and vomiting

BACKGROUND: So far there are three different scores to predict postoperative vomiting (PV: Apfel et al., 1998) or postoperative nausea and vomiting (PONV: Koivuranta et al., 1997; Palazzo and Evans, 1993). All three scores used logistic regression analysis to identify and create weights for the risk factors for PV or PONV. In short, these were sex, age, history of previous PONV, motion sickness, duration of anaesthesia, and use of postoperative opioids. However, an external evaluation and a comparison of these scores has not been performed so far. METHODS: Patients undergoing a variety of surgical procedures under general anaesthesia were studied prospectively. Preoperatively, they completed a questionnaire concerning potential risk factors for the occurrence of PV or PONV implemented in the three risk scores. Balanced anaesthesia (induction agent, nondepolarising neuromuscular blocker, opioid, and inhalation agent in nitrous oxide/oxygen) was performed. No intravenous anaesthesia or any antiemetic prophylaxis was applied. Postoperatively, the patients were observed in the recovery room for the occurrence of PV and PONV and were visited twice on the ward within the 24-h observation period. Both the patients and the nursing staff were asked whether PV or PONV was present. The severity of PONV was categorised using a standardised scoring algorithm. A total of 1,444 patients was finally included into the analysis. Using information of the predicted risk for the individual patients and the actual occurrence of PV or PONV, Receiver Operator Characteristics (ROC-curves) were drawn. The area under each ROC-curve was calculated as a means of the predictive properties of each score and was compared for statistical differences. RESULTS: For prediction of PONV (any severity) the AUC-values (AUC=area under the curve) and the corresponding 95%-confidence intervals were: Apfel: 0.70 (0.67-0.72); Koivuranta: 0.71 (0.69-0.73); Palazzo: 0.68 (0.65-0.70). For prediction of PV: Apfel: 0.73 (0.71-0.75); Koivuranta: 0.73 (0.70-0.75); Palazzo: 0.68 (0.65-0.70). Thus, all three scores appeared to have a moderate accuracy as measured by the AUC. The score of Koivuranta predicts PONV (P=0.007) and also PV (P=0.002) significantly better than Palazzo's score. Furthermore, for predicting of PV the score of Apfel was also superior to Palazzo's score (P=0.005). All three scores predict PV with the same accuracy as PONV. CONCLUSION: The occurrence of PV and PONV in patients undergoing surgery under balanced anaesthesia can be predicted with moderate but acceptable accuracy using one of the available risk scores, regardless of local surgical or anaesthesiological circumstances. For clinical practice, we recommend the score published by Koivuranta, since its calculation is very simple.     

Effects of preoperative,scheduled administration of antiemetics in reducing postoperative nausea and vomiting in patients undergoing total knee arthroplasty

There is no established protocol regarding the timing of administration of antiemetics in patients undergoing total knee arthroplasty (TKA). The purpose of this study was to determine whether preoperative, rather than postoperative administration of an antiemetic could reduce postoperative nausea and vomiting (PONV) in patients undergoing TKA, and whether there was a difference in postoperative pain, patient satisfaction and complications after TKA between the 2 different administration times.The included patients (N = 101) either received intravenous administration of the ramosetron 1 hour before surgery (N = 50) or at the end of surgery (N = 51) consecutively order. The incidence of PONV and the frequency of rescue medicine use were recorded until 48 hours postoperatively. The severity of postoperative pain and patient satisfaction were assessed using the visual analogue scale. The incidence of complications associated with use of antiemetic was assessed.Preoperative administration of ramosetron did not decrease PONV during the first 48 hours. There was no significant difference in the incidence of nausea and vomiting, use of rescue antiemetics, and the severity of nausea (P > .05). Postoperative pain, satisfaction scores, and the incidence of complications were not different between the 2 groups (P > .05).Preoperative administration of ramosetron did not show clinical advantage in reducing POVN, postoperative pain and improving patient satisfaction. However, the outcomes of complications were not inferior to those of postoperative administration. Therefore, under the current protocol of multimodal therapies, timing of administration of pre-emptive antiemetic did not have significant effect on PONV.     

Supplemental peri-operative intravenous crystalloids for postoperative nausea and vomiting: an abridged Cochrane systematic review

We conducted a Cochrane systematic review on the effectiveness of supplemental intravenous crystalloid administration in preventing postoperative nausea and vomiting. We included randomised controlled trials of patients undergoing surgery under general anaesthesia and given supplemental peri-operative intravenous crystalloid. Our primary outcomes were the risk of postoperative nausea and the risk of postoperative vomiting. We assessed the risk of bias for each included study and applied the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) framework for the certainty of evidence. We included 41 studies. We found that the intervention probably reduces the overall risk of postoperative nausea, the risk ratio (95%CI) being 0.62 (0.51–0.75) (I² = 57%, p < 0.00001, 18 studies; 1766 participants; moderate-certainty evidence). It also probably reduces the risk of postoperative nausea within 6 h of surgery, with a risk ratio (95%CI) of 0.67 (0.58 to 0.78) (I² = 9%, p < 0.00001, 20 studies; 2310 participants; moderate-certainty evidence) and by around 24 h, the risk ratio (95%CI) being 0.47 (0.32–0.69) (I² = 38%, p = 0.0001, 17 studies; 1682 participants; moderate-certainty evidence). Supplemental intravenous crystalloid probably also reduces the overall risk of postoperative vomiting, with a risk ratio (95%CI) of 0.50 (0.40–0.63) (I² = 31%, p < 0.00001, 20 studies; 1970 participants; moderate-certainty evidence). The beneficial effect on vomiting was seen both within 6 h and by around 24 h postoperatively.     

Comparação entre anestesia intravenosa e inalatória na náusea e vômito pós‐operatórios em laparotomia: estudo clínico randomizado

BackgroundPostoperative Nausea and Vomiting (PONV) is a multifactorial surgical complication with an unclear underlying cause. Anesthetic methods, patients’ characteristics and the type of surgery are considered as factors affecting PONV. This study was designed to compare the effect of inhalational and intravenous anesthesia in abdominal surgery on the incidence and severity of PONV.MethodsA single‐blinded prospective randomized clinical trial on 105 patients aged 18 − 65 years was carried out. Patients were divided in two groups of Total Intravenous Anesthesia (TIVA) and Inhalational anesthesia. The incidence and severity of PONV were examined at 0, 2, 6, 12, and 24 hours after the surgery. The use of a rescue antiemetic was also evaluated.ResultsFifty point nine percent of the patients in the inhalation group and 17.3% of the patients in the intravenous group developed PONV (p < 0.001). The incidence of vomiting was reported in 11.3% of the Inhalational group and 3.8% of the TIVA group (p = 0.15), and 24.5% of patients in the Inhalation group and 9.6% of patients in the intravenous group needed an antiemetic medication (p = 0.043).ConclusionThe incidence of postoperative nausea and vomiting and the need for administration of an antiemetic rescue drug, and the severity of nausea in patients were significantly lower in the TIVA group.     

Recent advances,trends and economic considerations in the risk assessment,prevention and treatment of postoperative nausea and vomiting

During the last two decades there have been considerable achievements regarding the management of postoperative nausea and vomiting (PONV). Due to the importance of these symptoms in the aim to streamline clinical processes and to improve patient satisfaction, the debate on the best strategies and also research that focuses on PONV continues. This review summarises the recent developments with respect to the management of PONV. Following a brief review on what is already known on the risk assessment, prevention and treatment of PONV, newer trends in the pharmacological prevention (dexamethasone, neurokinin-1 antagonists, multimodal prevention) will be discussed as well as new insights regarding the value of algorithms for the prevention of PONV. Further, pharmacogenetically based algorithms (according to the metaboliser status) as well as new treatment strategies (dexamethasone, multimodal treatment) will be covered. No drug so far can achieve a reduction of PONV of more than one third. Furthermore, all clinical studies consistently demonstrated that a combination treatment has a simple additive effect without any relevant interaction between different drugs or classes of drugs. The relative reduction of ～ 30% can also be expected from dexamethasone and it is likely that the substances presently in development and in an early clinical use (e.g., neurokinin-1 antagonists) will not represent the new panacea. However, they will probably replenish the existing antiemetic portfolio to better cope with high risk patients. Stratified prevention using pharmacogenetic knowledge is still in the early stages. Algorithms need to be customised to the local settings in order to prove efficient. Treatment remains a most important pillar and there is evidence that the principles of combining antiemetics to prolong effects and improve protection can be similarly applied to treatment. Recent developments in the area of PONV are more related to implementing the already existing evidence than based on the introduction of new molecules. New molecules replenish the pharmacological antiemetic portfolio, which is needed due to the limited efficacy of any single agent available so far. The new neurokinin-1 receptor antagonist, aprepitant, and the long lasting 5-HT₃ receptor antagonist palonosetron are the latest developments in this context. Treatment is most important and can also be regarded as a secondary prevention. Due to limited efficacy of single treatment interventions, combination therapy may gain more widespread use in the future.     

枢星防治曲马多术后镇痛患者恶心呕吐的研究

目的观察枢星(格拉司琼)不同给药模式对曲马多经静脉自控术后镇痛(PCIA)时恶心呕吐及血浆胃动素水平的影响。方法54例择期子宫切除术患者,术后行曲马多PCIA。按枢星给药模式不同分成3组,Ⅰ组为枢星3 mg加入曲马多镇痛泵中;Ⅱ组为枢星3 mg在给曲马多负荷量前5 min缓慢静注;Ⅲ组为单次静注枢星3 mg,并在镇痛泵中加枢星3 mg。分别测定入室、术毕、术后6、24、42 h血浆胃动素水平,并观察恶心、呕吐程度及发生率。结果Ⅰ组有8例发生Ⅱ~Ⅳ级恶心、呕吐,发生率为44.4%,Ⅱ组为3例,Ⅲ组为2例,分别为16.7%和11.1%。从入室到术毕胃动素浓度增高,Ⅰ组术后仍维持较高水平,Ⅱ、Ⅲ组术后6 h低于术毕水平(P<0.05);同时Ⅱ、Ⅲ组在术后6 h2、4 h时低于Ⅰ组(P<0.05)。结论应用枢星防治曲马多所致恶心呕吐时,须使用负荷量,且其作用与抑制血浆胃动素的合成及分泌有关。     

Rectally administered diclofenac (Voltaren) reduces vomiting compared with opioid (morphine) after strabismus surgery in children

BACKGROUND: Nausea, vomiting and pain are common complications after strabismus surgery in children. Diclofenac, a non-steroid anti-inflammatory drug, is widely used to treat acute and chronic pain but there are few reports of its use given rectally in children undergoing strabismus surgery. This open randomised study was designed to investigate the analgesic and anti-emetic properties of rectally administered diclofenac compared with opioid (morphine) given i.v. in connection with strabismus surgery in children. METHODS: After obtaining approval from the local ethics committee and written informed consent from the parents, 50 ASA class I-II children, 4-16 years of age, were randomised to receive either rectally administered diclofenac (Voltaren) 1 mg/kg or i.v. opioid (morphine) 0.05 mg/kg perioperatively. The children were consecutively operated upon from May 1999 to January 2001. Anaesthesia was induced with fentanyl and propofol and maintained with propofol. Nitrous oxide was omitted. The postoperative pain was assessed after arrival at the post anaesthesia care unit (PACU) by using the validated Wong and Baker scale (FACES) Pain Rating Scale. Postoperative nausea and vomiting (PONV) was assessed by measuring the frequency of vomiting and the degree of nausea. RESULTS: In the diclofenac group the incidence of PONV during the first 24 h was 12% (of which one child had severe vomiting). The incidence of PONV was much higher, 72% (P = 0.0000), in the morphine group, where 56% of the children also had severe vomiting. There were no difference in pain score between the two groups. Recovery time at the PACU was longer (P < 0.002) and the postoperative analgesic requirement higher in the morphine group (10 vs. 5 children). No children needed overnight admission to the hospital. CONCLUSION: Diclofenac given rectally is an effective analgesic for this kind of surgery and gives less postoperative nausea than i.v. morphine. No serious adverse events were observed.     

The addition of antiemetics to the morphine solution in patient controlled analgesia syringes used by children after an appendicectomy does not reduce the incidence of postoperative nausea and vomiting

BACKGROUND: We studied the effect of intraoperative ondansetron 0.1 mg x kg(-1) or droperidol 0.01 mg.kg-1, followed by the same dose of the antiemetic agent added to the morphine solution during patient controlled analgesia (PCA) on the incidence of nausea and vomiting in children following an appendicectomy. METHODS: Sixty children, aged 5-13 years, were recruited and randomly allocated to receive no prophylactic antiemetic, the control group (group C), ondansetron (group O) or droperidol (group D). The PCA pump was programmed to deliver a bolus dose of 20 microg x kg(-1) of morphine.with a 5-min lockout period and a background infusion of 4 microg x kg(-1) x h(-1). RESULTS: Postoperatively, the three groups were compared for nausea, vomiting and sedation scores for 24 h. The incidence of postoperative nausea and vomiting was 33% for group C, 44% for group O and 41% for group D. There was no increase in sedation scores in the droperidol group. CONCLUSIONS: We were unable to show any significant benefit from the prophylactic administration of ondansetron or droperidol to children using morphine PCA devices following appendicectomy in the doses we employed.