Dimenhydrinate for prophylaxis of postoperative nausea and vomiting: a meta-analysis of randomized controlled trials

BACKGROUND: Diphenhydramine and its theoclate salt dimenhydrinate are traditional antiemetics still in use. However, so far the quantitative effect of dimenhydrinate in the prophylaxis of postoperative nausea and vomiting (PONV) has not been evaluated systematically. METHODS: Results from randomized controlled trials investigating the efficacy of dimenhydrinate vs. a control to prevent PONV were included in a meta-analysis. Studies were systematically searched through MEDLINE, EMBASE, the Cochrane-Library, manually screening of reference lists of matching review articles and current issues of locally available peer-reviewed anesthesia journals, up to June 2001. The numbers of patients with complete absence of PONV within 6 h and within 48 h after surgery were extracted as the main end point. Pooled relative benefits (RB) and numbers-needed-to-treat (NNT) with their corresponding 95% confidence intervals (CI) were calculated using a random effects model. This quantitative systematic review was performed following the recommendations of the QUORUM statement. In all, 18 trials with 3045 patients were included in the analysis: 1658 patients received a placebo (control) and 1387 patients received dimenhydrinate. RESULTS: The RB to stay completely free of PONV was 1.2 (95% CI: 1.1-1.4) for the early period (NNT = 8; 95% CI: 5-25) and 1.5 (1.3-1.8) for the overall investigated period (NNT = 5; 95% CI: 3-9). CONCLUSION: Dimenhydrinate is a traditional and inexpensive antiemetic with an efficacy that might be considered as clinically relevant. Although in use for a long time, the dose-response, precise estimation of side-effects, optimal time of administration and the benefit of repetitive doses still remain unclear.     

Sevoflurane versus desflurane for early postoperative vomiting after general anesthesia in hospitalized adults: A systematic review and meta-analysis of randomized controlled trials

Study objectiveThis systematic review and meta-analysis aimed at assessing the effects of two commonly used anesthetics in general anesthesia (GA), sevoflurane and desflurane, on early postoperative vomiting (POV) in hospitalized adults.DesignSystematic review and meta-analysis of randomized controlled trials (RCTs).SettingEarly postoperative vomiting after GA.PatientsA total of 266 adult patients receiving inpatient surgeries under GA maintained with sevoflurane or desflurane.InterventionsWe searched PubMed, Medline, Cochrane Central Register of Controlled Trials, ScienceDirect, and Embase for eligible RCTs comparing postoperative outcomes following sevoflurane- or desflurane-maintained anesthesia.MeasurementsThe primary outcome was early POV. Secondary outcomes included late POV, early and late postoperative nausea (PON), time to extubation, and emergence time.Main resultsEight trials were included. There was no significant difference in the risk of early POV (risk ratio [RR] 1.03, 95% confidence interval [CI] 0.64–1.64, p = 0.91). No significant difference in early PON was observed (RR 1.09; 95% CI, 0.77–1.56; p = 0.62). Nevertheless, the incidence of late POV and late PON were significantly lower in the sevoflurane group than that in the desflurane group (RR 0.47, 95% CI 0.23–0.94, p = 0.03; RR 0.45, 95% CI 0.24–0.84, p = 0.01, respectively). The extubation time was longer in the sevoflurane group than in the desflurane group (standardized mean difference [SMD] 0.56, 95% CI 0.14–0.97, p = 0.009). The emergence time of patients in the sevoflurane group was longer than that in those receiving desflurane (SMD 0.76, 95% CI 0.1–1.42, p = 0.02).ConclusionsDesflurane had the same effects on early POV and early PON as sevoflurane. However, the association between late POV and late PON with desflurane was stronger than that with sevoflurane if the effects of opioids were not considered. The desflurane group had shorter time to extubation and emergence time than the sevoflurane group. PROSPERO registration number: CRD42020218988.     

Propofol anaesthesia and postoperative nausea and vomiting: quantitative systematic review of randomized controlled studies

We have analysed randomized controlled studies which reported the incidence of postoperative nausea and vomiting (PONV) after propofol anaesthesia compared with other anaesthetics (control). Cumulative data of early (0-6 h) and late (0-48 h) PONV were recorded as occurrence or non-occurrence of nausea or vomiting. Combined odds ratio and number- needed-to-treat were calculated for propofol as an induction or maintenance regimen, early or late outcomes, and different emetic events. This was performed for all control event rates and within a range of 20-60% control event rates. We analysed 84 studies involving 6069 patients. The effect of propofol on PONV was dependent mainly on the method of administration, time of measurement and range of control event rates. When all studies were included the number-needed-to-treat to prevent PONV with propofol was more than 9 when used for induction of anaesthesia and at best 6 when used for maintenance. Within the 20- 60% control event rate range, best results were achieved with propofol maintenance to prevent early PONV: the number-needed-to-treat to prevent early nausea was 4.7 (95% confidence interval 3.8-6.3), vomiting 4.9 (4-6.1) and any emetic event 4.9 (3.7-7.1). Within the 20- 60% control event rate, of five patients treated with propofol for maintenance of anaesthesia, one will not vomit or be nauseated in the immediate postoperative period who would otherwise have vomited or been nauseated. This may be clinically relevant. In all other situations the difference between propofol and control may have reached statistical significance but was of doubtful clinical relevance. Treatment efficacy should be established within a defined range of control event rates for meaningful estimates of efficacy and for comparisons.      

The effect of fibrinogen concentrate on postoperative blood loss: A systematic review and meta-analysis of randomized controlled trials

BackgroundLow level of fibrinogen is a risk factor of perioperative bleeding, which is a major complication in surgical patients. However, the safety and efficacy of fibrinogen supplementation with fibrinogen concentrate to minimize postoperative bleeding remains unclear.ObjectivesThe primary aim of this review was to investigate the effect of fibrinogen concentrate in postoperative blood loss in adult surgical patients.DesignSystematic review and meta-analysis.Data sourcesDatabases of MEDLINE, EMBASE and CENTRAL were searched from their start date until July 2019.Eligibility criteriaAll randomized clinical trials comparing intravenous fibrinogen concentrate and placebo in adult surgical patients were included, regardless of type of surgery. Observational studies, case reports, case series and non-systematic reviews were excluded.ResultsThirteen trials (n = 900) were included in this review. In comparison to placebo, fibrinogen concentrate significantly reduced the first 12-hour postoperative blood loss, with a mean difference of −134.6 ml (95% CI −181.9 to −87.4). It also significantly increased clot firmness in thromboelastometry (FIBTEM) with a mean difference of 2.5 mm (95%CI 1.1 to 3.8). No significant differences were demonstrated in the adverse events associated with fibrinogen concentrate use, namely incidence of thromboembolism, myocardial infarction and acute kidney injury.ConclusionsIn this meta-analysis of 13 randomized trials, low level of evidence and substantial heterogeneity with small sample size limit strong recommendation on the use of fibrinogen concentrate in adult surgical patients. However, its use is tolerable without any notable adverse events.Trial registrationCRD42019149164.     

Dexamethasone for prophylaxis of postoperative nausea and vomiting. A meta-analysis of randomized controlled studies

OBJECTIVE: Randomised controlled trials investigating the efficacy of dexamethasone alone or in combination with other antiemetics to prevent postoperative nausea and vomiting (PONV) were included in a meta-analysis to estimate the relative efficacy of these treatments. METHODS: Studies were systematically searched using Medline, EMBASE, the Cochrane-Library, and by manual screening the reference lists and current issues of locally available anaesthesia journals. Studies identified were divided into four different groups. For each subgroup an independent analysis was performed: 1. Dexamethasone vs. placebo, 2. Dexamethasone + other antiemetic vs. other antiemetic alone, 3. Dexamethasone + other antiemetic vs. dexamethasone alone, 4. Dexamethasone vs. other antiemetics. The main end point in each study was defined as complete absence of nausea, retching, and vomiting after prophylactic antiemetic treatment. The pooled odds-ratios, the relative risk (RR) and the numbers-needed-to-treat (NNT) with their corresponding 95%-confidence intervals (given in parentheses) were calculated using a random effects model. RESULTS: A total of 26 studies with 2561 patients were analysed. 1. As a sole antiemetic agent dexamethasone is superior to placebo to prevent PONV (RR: 0.49 (0.15-0.42); NNT: 3.4 (2.5-5.3)). 2. When dexamethasone and an other antiemetic (e.g. a 5-HT3-antagonist) are combined this drug combination is significantly more effective than the single antiemetic without dexamethasone (RR: 0.60 (0.46-0.78); NNT: 7.3 (5.7-10.2)). 3. A similar result was obtained when the dexamethasone combination was compared with dexamethasone alone. The combination is statistically superior (RR: 0.16 (0.08-0.32); NNT: 3.2 (2.2-6.3)). 4. Dexamethasone was usually compared with 5-HT3-antagonist and to a less extends also with dopamine antagonists. Summarising these studies, there was no significant difference concerning effectiveness (RR: 1.35 (0.99-1.85); NNT: 10.6 (5.6-92.6)). CONCLUSION: Dexamethasone has antiemetics effects that are superior to placebo treatment and are comparable with conventional antiemetic agents (e.g. 5-HT3-antagonist, dopamine antagonists). The drug is especially useful in combination with other antiemetics and increases the efficacy of the antiemetic partner drug.     

Intraoperative colloid administration reduces postoperative nausea and vomiting and improves postoperative outcomes compared with crystalloid administration

The debate over colloid versus crystalloid as the best solution for intraoperative fluid resuscitation is not resolved. Published studies have shown that mortality is not related to the specific fluid used for resuscitation. In addition, the quality of postoperative recovery between colloid and crystalloid has not been well investigated. In a prospective, blinded fashion, we investigated the effects of colloid and crystalloid resuscitation on nausea and vomiting and on the postoperative patient recovery profile. Patients undergoing major elective noncardiac surgery were randomized to receive 6% hetastarch in saline (HS-NS), 6% hetastarch in balanced salt (HS-BS), or lactated Ringer's solution (LR) on the basis of a fluid administration algorithm. The anesthetic was standardized. Hemodynamic targets included maintenance of arterial blood pressure, heart rate, and urine output within a predefined range. A postoperative morbidity survey was performed at baseline and daily after surgery. Ninety patients participated in the study, with 30 patients in each group. The amounts of study fluid (mean +/- SD) administered were 1301 +/- 1079 mL, 1448 +/- 759 mL, and 5946 +/- 1909 mL for the HS-NS, HS-BS, and LR groups, respectively (P < 0.05, HS-NS and HS-BS versus LR). Both the HS-NS and HS-BS (colloid) groups had a significantly less frequent incidence of nausea and vomiting, use of rescue antiemetics, severe pain, periorbital edema, and double vision. We concluded that intraoperative fluid resuscitation with colloid, when compared with crystalloid administration, is associated with an improvement in the quality of postoperative recovery.     

Efficacy of ginger for nausea and vomiting: a systematic review of randomized clinical trials

Ginger (Zingiber officinale) is often advocated as beneficial for nausea and vomiting. Whether the herb is truly efficacious for this condition is, however, still a matter of debate. We have performed a systematic review of the evidence from randomized controlled trials for or against the efficacy of ginger for nausea and vomiting. Six studies met all inclusion criteria and were reviewed. Three on postoperative nausea and vomiting were identified and two of these suggested that ginger was superior to placebo and equally effective as metoclopramide. The pooled absolute risk reduction for the incidence of postoperative nausea, however, indicated a non-significant difference between the ginger and placebo groups for ginger 1 g taken before operation (absolute risk reduction 0.052 (95% confidence interval -0.082 to 0.186)). One study was found for each of the following conditions: seasickness, morning sickness and chemotherapy-induced nausea. These studies collectively favoured ginger over placebo.      

昂丹司琼预防妇科腹腔镜手术恶心呕吐的Meta分析

目的 系统评价昂丹司琼预防妇科腹腔镜全麻术后恶心呕吐(postoperative nausea and vomiting,PONV)的有效性和安全性. 方法 电子检索中国学术期刊全文数据库(CNKI)、中国生物医学文献数据库(CBM)、重庆维普中文科技期刊全文数据库、万方数据库、Pubmed、Springer、Embase、Web of knowledge数据库,并查阅所获文献的参考文献,收集1995～2012年发表的有关昂丹斯琼预防妇科腹腔镜全麻PONV的随机对照试验(randomized controlled trials,RCTs).按Cochrane Handbook5.0.1对纳入文献进行质量评价和资料提取,统计学分析采用Stata11.0软件. 结果共纳入18个RCT,包括1 597例患者.Meta分析结果显示:①有效性:昂丹司琼单次静脉注射能降低妇科腹腔镜全麻PONV的发生率[(RR=0.210,95％CI=0.164～0.268)];昂丹司琼4 mg与8 mg单次静脉注射对预防妇科腹腔镜全麻术后患者24 h PONV效果相当[(RR=0.948,95％CI=0.433～2.075)];手术前期应用昂丹司琼较术毕应用患者PONV发生率更低[(RR=0.450,95％CI=0.290～0.698)];昂丹斯琼4 mg或氟哌利多1.25 mg～2 mg静脉注射患者术后24 h PONV发生率相同[(RR=1.36,95％CI=0.74～2.51)];昂丹司琼联合氟哌利多静脉注射预防术后PONV发生较单独使用昂丹司琼效果更好[(RR=3.56,95％CI=1.74～7.29)].②安全性:昂丹司琼静脉注射不增加头痛、低热的发生率. 结论 昂丹司琼4 mg术前静脉注射能明显降低妇科腹腔镜全麻PONV的发生率,但并不能降低头痛、低热等副作用的发生率.昂丹司琼联合小剂量氟哌利多静脉注射较单独使用昂丹司琼对预防妇科腹腔镜全麻PONV的发生效果更好.     

Banded versus nonbanded Roux-en-Y gastric bypass: a systematic review and meta-analysis of randomized controlled trials

BackgroundBariatric surgery is remarkably effective in achieving weight loss and improving obesity-related co-morbidities; however, efforts still continue to improve its long-term outcomes. Particularly, banded Roux-en-Y gastric bypass (RYGB) has been scrutinized in comparison to standard (nonbanded) RYGB in terms of benefits and postoperative complications.ObjectivesThis study aims to compare the safety and efficacy of banded versus nonbanded RYGB.SettingMeta-analysis of randomized controlled trials (RCTs).MethodsA meta-analysis of high-quality studies that compared banded and nonbanded RYGB was conducted through February 2019 by systematically searching multiple electronic databases. Published RCTs comparing these 2 procedures were included to pool the data on excess weight loss, food tolerability, and postoperative complications.ResultsThree RCTs were eligible to be included in this meta-analysis, comprising a total of 494 patients (247 in each group). Two of the RCTs provided 2-year postoperative data, and 1 study reported 5-year outcome. Age ranged from 21 to 50 years, and body mass index ranged from 42 to 65 kg/m². Percentage of excess weight loss was significantly greater with banded RYGB than with nonbanded RYGB (mean difference 5.63%; 95% CI 3.26–8.00; P < .05). Postoperative food intolerance, emesis, and dysphagia were more common after banded RYGB (odds ratio 3.76; 95% CI 2.27–6.24; P < .001). Nevertheless, major postoperative complications did not significantly differ between the 2 groups.ConclusionFindings of this meta-analysis of RCTs indicate that in a medium-term follow-up, excess weight loss with banded RYGB would be 5% greater than that with the nonbanded RYGB (about 1 point difference in body mass index) at the expense of more food intolerance and postoperative vomiting; however, the frequency of postoperative complications would not be significantly different.     

Dexmedetomidine versus other sedatives for non-painful pediatric examinations: A systematic review and meta-analysis of randomized controlled trials

Study objectiveProcedural sedation for non-painful pediatric examinations outside the operating room remains a challenge, this study was designed to compare the safety and effectiveness of sedation provided by dexmedetomidine versus other sedatives including chloral hydrate, midazolam, and pentobarbital for pediatric patients to complete diagnostic examinations.DesignSystematic review and meta-analysis of RCTs.SettingPediatric procedural sedation.InterventionsComparison of sedation by dexmedetomidine and chloral hydrate, or pentobarbital, or midazolam for pediatric non-painful sedation.PatientsThe PubMed, Embase, and Cochrane Library databases and the Cochrane Controlled Trials Register for randomized clinical trials were searched and limited the studies to those published in English through July 30, 2018.MeasurementsProspective randomized clinical trials (RCTs) comparing dexmedetomidine to chloral hydrate, pentobarbital, and midazolam for pediatric procedural examinations outside the operating room were included in the meta-analysis. Search terms included dexmedetomidine, precede, adrenergic alpha-2 receptor agonists, adrenergic alpha 2 agonists, adrenergic alpha-agonists, adrenergic alpha 2 receptor agonists, chloral hydrate, pentobarbital, midazolam, AND sedation.Main resultsA total of 1486 studies were screened and nine RCTs were identified; 1076 patients were analyzed. Sedation with dexmedetomidine provided statistically higher incidences in completing examinations with fewer episodes of desaturation than the other sedatives did (OR 2.90, 95% CI: 1.39–6.07, P = 0.005, I² = 77%; OR 0.29, 95% CI: 0.15–0.57, P = 0.0004, I² = 0%, respectively).ConclusionsThe meta-analysis shows that sedation by dexmedetomidine has lower incidence of respiratory depression and provides higher success rates in completing examinations than other traditional sedatives without compromising safety, indicating a prospective clinical use for procedural sedation.     

Supplemental oxygen for the prevention of postoperative nausea and vomiting: a meta-analysis of randomized clinical trials

OBJECTIVE: Despite the development of antiemetic drugs, the incidence of postoperative nausea and vomiting remains between 20% and 30%. This meta-analysis examines the hypothesis that perioperative administration of supplemental oxygen reduces the incidence of these complications. METHODS: We performed a systematic search of the literature through MEDLINE, EMBASE, the Cochrane Library, reference lists, and a manual search, with no language restrictions, up to September 2007 to identify randomized clinical trials evaluating the effect o f supplemental oxygen on postoperative nausea and vomiting. The data were extracted and analyzed using the RevMan program, version 4.2.9 (Cochrane Collaboration, Oxford, UK). RESULTS: The study included 9 randomized clinical trials with a total of 1661 enrolled patients (824 assigned to the group with a higher oxygen concentration and 837 assigned to the group with a lower oxygen concentration). Perioperative supplemental oxygen has no effect on the incidence of nausea (relative risk [RR], 0.94; 95% confidence interval [CI], 0.82 to 1.08), postoperative nausea and/or vomiting (RR, 0.93; 95% CI, 0.74 to 1.17), or the need for rescue antiemetic drugs (RR, 0.90; 95% CI, 0.70 to 1.15). The incidence of vomiting, however, is reduced (RR, 0.77; 95% CI, 0.62 to 0.97). Significant differences were not found in the incidence of atelectasis (RR, 1.23; 95% CI, 0.50 to 3.00) or postoperative PaCO2 (weighted mean difference, -4.0; 95% CI, -12.3 to 4.3). CONCLUSIONS: Supplemental oxygen reduces the incidence of postoperative vomiting. Administration of supplemental oxygen could be an effective method of reducing postoperative vomiting but does not replace current indications for pharmacologic prophylaxis.     

Opioid versus non-opioid analgesia for spine surgery: a systematic review and meta-analysis of randomized controlled trials

Purpose

Opioids are the primary analgesics used in patients undergoing spine surgery. Postoperative pain is common despite their liberal use and so are opioid-associated side effects. Non-opioid analgesics are gaining popularity as alternative to opioids in spine surgery.

Methods

This systematic review evaluated current evidence regarding opioid and non-opioid intraoperative analgesia and their influence on immediate postoperative pain and adverse events in spine surgery.

Results

A total of 10,459 records were obtained by searching Medline, EMBASE and Web of Science databases and six randomized controlled trials were included. Differences in postoperative pain scores between opioid and non-opioid groups were not significant at 1 h: 4 studies, mean difference (MD) = 0.65 units, 95% confidence intervals (CI) [−0.12 to 1.41], p = 0.10, but favored non-opioid at 24 h after surgery: 3 studies, MD = 0.75 units, 95%CI [0.03 to 1.46], p = 0.04. The time for first postoperative analgesic requirement was shorter (MD = −45.06 min, 95%CI [−72.50 to −17.62], p = 0.001), and morphine consumption during first 24 h after surgery was higher in opioid compared to non-opioid group (MD = 4.54 mg, 95%CI [3.26 to 5.82], p < 0.00001). Adverse effects of postoperative nausea and vomiting (Relative risk (RR) = 2.15, 95%CI [1.37 to 3.38], p = 0.0009) and shivering (RR = 2.52, 95%CI [1.08 to 5.89], p = 0.03) were higher and bradycardia was lower (RR = 0.35, 95%CI [0.17 to 0.71], p = 0.004) with opioid analgesia.

Conclusion

The certainty of evidence on GRADE assessment is low for studied outcomes. Available evidence supports intraoperative non-opioid analgesia for overall postoperative pain outcomes in spine surgery. More research is needed to find the best drug combination and dosing regimen.

Prospero Registration: CRD42020209042.