Intravenous Amisulpride for the Prevention of Postoperative Nausea and Vomiting

A Postoperative Nausea and Vomiting Update: Current information on New Drugs, Old Drugs, Rescue/Treatment, Combination Therapies and Nontraditional Modalities

This article's objective is to present the latest evidence and information on the management of postoperative nausea and vomiting (PONV). PONV continues to affect 30% of the surgical population causing patient dissatisfaction, extending length of stay, and increasing overall costs. This review includes the introduction of 2 new intravenous formulations of antiemetics (amisulpride, aprepitant), updates on nontraditional therapies, suggestions for combination prophylaxis, emerging data on rescue treatment, and considerations for special populations and settings. Both of the new antiemetics provide promising options for pharmacologic interventions for PONV with favorable safety profiles.

Perioperative utility of amisulpride and dopamine receptor antagonist antiemetics-a narrative review

Despite advances in antiemetics and protocolized postoperative nausea vomiting (PONV) management, it remains one of the most common postoperative adverse events. In patients who developed PONV despite antiemetic prophylaxis, giving a rescue treatment from the same class of medication is known to be of limited efficacy. Given the widespread use of 5-HT3 antagonists as PONV prophylaxis, another class of effective intravenous rescue antiemetic is in dire need, especially when prophylaxis fails, and rescue medication is utilized. Dopamine antagonists were widely used for the treatment of PONV but have fallen out of favor due to some of their side effect profiles. Amisulpride was first designed as an antipsychotic medication but was found to have antiemetic properties. Here we will review the historical perspective on the use of dopamine receptor antagonist antiemetics, as well as the evidence on the efficacy and safety of amisulpride.

Evaluation of the Role of Preoperative Oral Amisulpride as Part of a Multimodal Antiemetic Prophylaxis Regime on Postoperative Nausea and Vomiting in Patients Undergoing Craniotomy: A Prospective, Double-Blind, Randomized, Placebo-controlled Study

BACKGROUND

Patients undergoing craniotomy are at high risk for postoperative nausea and vomiting (PONV) despite the use of prophylactic antiemetics. We hypothesized that a single preoperative oral dose of amisulpride as part of a multimodal antiemetic regimen would decrease the incidence of PONV in patients undergoing craniotomy for intracranial tumor surgery.

METHODS

Adult patients scheduled for elective craniotomy requiring general anesthesia were enrolled and randomized to receive either oral amisulpride 25 mg or placebo 2 hours before surgery in addition to our institution's usual antiemetic regimen. The primary outcome of the study was the incidence of nausea and/or vomiting during the first 24 hours postoperatively. Secondary outcomes included severity of nausea, use of rescue antiemetic medications, and treatment-related adverse events.

RESULTS

A total of 100 patients were included in the analysis. More patients in the amisulpride group had no episodes of nausea (90% vs. 40%; P<0.001) and no episodes of vomiting (94% vs. 46%; P<0.001) compared with the placebo group. The severity of nausea was lower in the amisulpride group than in the control group in the first 4 hours after surgery (P<0.05), and fewer patients receiving amisulpride required rescue antiemetics (P<0.001). The incidence of treatment-related adverse events was similar between groups.

CONCLUSIONS

A single preoperative oral dose of amisulpride 25 mg as a component of a multimodal antiemetic regimen decreased the incidence and severity of PONV in patients undergoing craniotomy for intracranial tumor surgery, with no adverse effects.

Multicentre randomised trials in anaesthesia: an analysis using Bayesian metrics

Are the results of randomised trials reliable and are p values and confidence intervals the best way of quantifying efficacy? Low power is common in medical research, which reduces the probability of obtaining a 'significant result' and declaring the intervention had an effect. Metrics derived from Bayesian methods may provide an insight into trial data unavailable from p values and confidence intervals. We did a structured review of multicentre trials in anaesthesia that were published in the New England Journal of Medicine, The Lancet, Journal of the American Medical Association, British Journal of Anaesthesia and Anesthesiology between February 2011 and November 2021. We documented whether trials declared a non-zero effect by an intervention on the primary outcome. We documented the expected and observed effect sizes. We calculated a Bayes factor from the published trial data indicating the probability of the data under the null hypothesis of zero effect relative to the alternative hypothesis of a non-zero effect. We used the Bayes factor to calculate the post-test probability of zero effect for the intervention (having assumed 50% belief in zero effect before the trial). We contacted all authors to estimate the costs of running the trials. The median (IQR [range]) hypothesised and observed absolute effect sizes were 7% (3-13% [0-25%]) vs. 2% (1-7% [0-24%]), respectively. Non-zero effects were declared for 12/56 outcomes (21%). The Bayes factor favouring a zero effect relative to a non-zero effect for these 12 trials was 0.000001-1.9, with post-test zero effect probabilities for the intervention of 0.0001-65%. The other 44 trials did not declare non-zero effects, with Bayes factors favouring zero effect of 1-688, and post-test probabilities of zero effect of 53-99%. The median (IQR [range]) study costs reported by 20 corresponding authors in US$ were $1,425,669 ($514,766-$2,526,807 [$120,758-$24,763,921]). We think that inadequate power and mortality as an outcome are why few trials declared non-zero effects. Bayes factors and post-test probabilities provide a useful insight into trial results, particularly when p values approximate the significance threshold.

Management of postoperative nausea and vomiting in adults: current controversies

PURPOSE OF REVIEW

Postoperative nausea and vomiting (PONV) continue to plague the surgical patient population with an adverse impact on postoperative outcomes. The aim of this review is to critically assess current evidence for PONV management, including studies evaluating baseline risk reduction and antiemetic prophylaxis, to provide a pragmatic approach to prevention and treatment of PONV in routine clinical practice.

RECENT FINDINGS

Multiple recent reviews and guidelines have been published on this topic with some limitations. In the current ERAS era, all patients irrespective of their PONV risk should receive two to three antiemetics for prophylaxis. Patients at a high risk of PONV [i.e. prior history of PONV, history of motion sickness, high opioid requirements after surgery (e.g. inability to use nonopioid analgesic techniques)] should receive three to four antiemetics for prophylaxis.

SUMMARY

This review provides a practical approach to PONV prevention based on recent literature.

Drugs in anesthesia: preventing postoperative nausea and vomiting

PURPOSE OF REVIEW

Postoperative nausea and vomiting (PONV) continues to be a burden for patients, medical staff and healthcare facilities because of inadequate adherence to available recommendations. This review gives an overview on recent recommendations, new evidence and remaining issues in the field of PONV management.

RECENT FINDINGS

A wide range of drugs is available for the management of PONV including corticosteroids, 5-HT3-antagonists, dopamine-antagonists, neurokinin-receptor-1 (NK1)-antagonists, antihistamines and anticholinergics. The updated PONV guidelines from 2020 recommend a universal multimodal strategy for PONV prophylaxis, which is an important paradigm shift to improve implementation of the existing evidence. A recent Cochrane network meta-analysis ranked single drugs and drug combinations for PONV prophylaxis in terms of efficacy and safety. Notably, NK1-antagonists and new 5-HT3-antagonists ranged among the most effective drugs. However, safety data on antiemetics are generally scarce.

SUMMARY

Numerous drug (combinations) and strategies are available for PONV management. New and very effective (single) drugs could result in a simplification compared with a combination of several drugs, and thus lead to better implementation.

Amisulpride: A Review in Post-Operative Nausea and Vomiting

Amisulpride intravenous (IV) injection (Barhemsys^®; hereafter referred to as IV amisulpride), a selective dopamine receptor antagonist, is approved in the USA as a single IV infusion for the prevention and treatment of post-operative nausea and vomiting (PONV) in adults. Results from placebo-controlled phase III trials showed that IV amisulpride is efficacious both in the prevention of PONV (used either alone or in combination with an antiemetic of a different class) and in the treatment of PONV (irrespective of prior antiemetic prophylaxis status). When administered as a single IV infusion, amisulpride had a tolerability profile that was generally similar to that of placebo, with no significant safety concerns identified. Thus, IV amisulpride is a useful additional option in the prevention and treatment of PONV in adults, particularly for patients who have failed previous antiemetic prophylaxis and for whom effective treatment options may be limited.

Intravenous Amisulpride Does Not Meaningfully Prolong the QTc Interval at Doses Effective for the Management of Postoperative Nausea and Vomiting

BACKGROUND

Postoperative nausea and vomiting (PONV) are significant issues in surgical patients, and additional treatment options are needed. Dopaminergic antiemetics have been popular for their efficacy, but their use has been limited by safety concerns, especially the potential for torsade de pointes arising from QT interval prolongation. Intravenous (IV) amisulpride, a dopamine D2 and D3 antagonist shown to be effective at preventing and treating PONV at doses of 5 and 10 mg, respectively, has a dose-dependent effect on QT but at 5 mg is not associated with clinically meaningful prolongation of the heart rate-corrected QT (QTc) interval. This study was designed to evaluate the QT effect of a 10-mg dose of amisulpride, alone and when simultaneously coadministered with ondansetron, an antiemetic of a different class, also known to prolong the QT interval.

METHODS

In this randomized, double-blind, placebo-controlled, 3-period, crossover study, healthy male and female volunteers 18-65 years of age received IV, in a random sequence: (1) amisulpride 10 mg given twice, 2 hours apart; (2) amisulpride 10 mg and ondansetron 4 mg, given simultaneously; and (3) placebo.

RESULTS

Thirty subjects were enrolled, and 29 completed all 3 treatment periods. The largest mean placebo-corrected change-from-baseline QT interval corrected for heart rate using Fridericia's formula (QTcF) (ΔΔQTcF) after the first and second amisulpride dose was 5.2 milliseconds (90% confidence interval [CI], 3.53-6.96 milliseconds) and 8.0 milliseconds (90% CI, 5.49-10.58 milliseconds), respectively. After coadministration of amisulpride and ondansetron, the largest mean ΔΔQTcF was 7.3 milliseconds (90% CI, 5.48-9.16 milliseconds). The slope of the amisulpride concentration-change-from-baseline QTcF (ΔQTcF) relationship was 0.006 ms/ng/mL (90% CI, 0.0020-0.0098). No QTc outliers (absolute QTcF value >480 milliseconds or increase from baseline >30 milliseconds) were seen in any period.

CONCLUSIONS

A 10-mg dose of IV amisulpride, given alone or in combination with ondansetron, does not have a clinically significant effect on the QT interval.

Amisulpride: A New Drug for Management of Postoperative Nausea and Vomiting

OBJECTIVE

To review the pharmacology, efficacy, and safety of amisulpride and determine its role in the management of postoperative nausea and vomiting (PONV).

DATA SOURCES

A PubMed search (1946 to November 2020) using the terms amisulpride and APD421 was conducted.

STUDY SELECTION AND DATA EXTRACTION

Relevant reports on intravenous amisulpride were included.

DATA SYNTHESIS

Six clinical trials were evaluated. In 4 trials on the prevention of PONV, a greater percentage of patients who received amisulpride 5 mg compared with placebo experienced a complete response (44%-60% vs 31%-33%, respectively, when used as monotherapy; 58% vs 47%, respectively, when used in combination with another antiemetic). In 2 trials on the treatment of PONV, a significantly greater percentage of patients who received amisulpride 10 mg compared with placebo experienced a complete response (31.4% vs 21.5%, respectively, in patients who had not received prophylaxis; 41.7% vs 28.5%, respectively, in patients who had received prophylaxis). Adverse effects included infusion site pain, chills, hypokalemia, procedural hypotension, and abdominal distension.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Amisulpride is effective for the management of PONV and may be less likely to cause QT prolongation and extrapyramidal symptoms than other dopamine antagonists. Additional information is needed on its use for chemotherapy-induced nausea and vomiting and in children.

CONCLUSIONS

Amisulpride is an important new option for the multimodal management of PONV in adults, and it may be the preferred dopamine antagonist because of the more favorable safety profile that results from its unique pharmacological properties.

Prevention and Treatment of Postoperative Nausea and Vomiting (PONV): A Review of Current Recommendations and Emerging Therapies

Postoperative nausea and vomiting is one of the most frequent adverse events after surgery and anesthesia. It is distressing for the patient and can lead to other postoperative complications. Management of PONV involves a framework of risk assessment, multimodal risk reduction, and prophylactic measures, as well as prompt rescue treatment. There has been a significant paradigm shift in the approach towards PONV prevention. There have also been several emerging therapeutic options for PONV prophylaxis and treatment. In this review, we will discuss the up-to-date PONV management guidelines and highlight novel therapeutic options which have emerged in the last few years.

Design and conduct of confirmatory chronic pain clinical trials

The purpose of this article is to provide readers with a basis for understanding the emerging science of clinical trials and to provide a set of practical, evidence-based suggestions for designing and executing confirmatory clinical trials in a manner that minimizes measurement error. The most important step in creating a mindset of quality clinical research is to abandon the antiquated concept that clinical trials are a method for capturing data from clinical practice and shifting to a concept of the clinical trial as a measurement system, consisting of an interconnected set of processes, each of which must be in calibration for the trial to generate an accurate and reliable estimate of the efficacy (and safety) of a given treatment. The status quo of inaccurate, unreliable, and protracted clinical trials is unacceptable and unsustainable. This article gathers aspects of study design and conduct under a single broad umbrella of techniques available to improve the accuracy and reliability of confirmatory clinical trials across traditional domain boundaries.

The next generation of antiemetics for the management of postoperative nausea and vomiting

Postoperative nausea and vomiting (PONV) afflict approximately 30% of patients overall and up to 80% of high-risk patients after surgery. Optimal pharmacological prophylaxis of PONV is challenging as it necessitates the consideration of PONV risk, drug efficacy, and potential adverse effects. Despite significant advances in our understanding of the pathophysiology and risk factors of PONV, its incidence has remained largely unchanged. Newer antiemetics have been introduced that may have improved safety profiles, longer duration of action, and better efficacy. This review aims to summarize the recent developments pertaining to these new agents and their potential application toward the management of PONV.

Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network meta-analysis

BACKGROUND

Postoperative nausea and vomiting (PONV) is a common adverse effect of anaesthesia and surgery. Up to 80% of patients may be affected. These outcomes are a major cause of patient dissatisfaction and may lead to prolonged hospital stay and higher costs of care along with more severe complications. Many antiemetic drugs are available for prophylaxis. They have various mechanisms of action and side effects, but there is still uncertainty about which drugs are most effective with the fewest side effects.

OBJECTIVES

• To compare the efficacy and safety of different prophylactic pharmacologic interventions (antiemetic drugs) against no treatment, against placebo, or against each other (as monotherapy or combination prophylaxis) for prevention of postoperative nausea and vomiting in adults undergoing any type of surgery under general anaesthesia • To generate a clinically useful ranking of antiemetic drugs (monotherapy and combination prophylaxis) based on efficacy and safety • To identify the best dose or dose range of antiemetic drugs in terms of efficacy and safety SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), ClinicalTrials.gov, and reference lists of relevant systematic reviews. The first search was performed in November 2017 and was updated in April 2020. In the update of the search, 39 eligible studies were found that were not included in the analysis (listed as awaiting classification).

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing effectiveness or side effects of single antiemetic drugs in any dose or combination against each other or against an inactive control in adults undergoing any type of surgery under general anaesthesia. All antiemetic drugs belonged to one of the following substance classes: 5-HT₃ receptor antagonists, D₂ receptor antagonists, NK₁ receptor antagonists, corticosteroids, antihistamines, and anticholinergics. No language restrictions were applied. Abstract publications were excluded.

DATA COLLECTION AND ANALYSIS

A review team of 11 authors independently assessed trials for inclusion and risk of bias and subsequently extracted data. We performed pair-wise meta-analyses for drugs of direct interest (amisulpride, aprepitant, casopitant, dexamethasone, dimenhydrinate, dolasetron, droperidol, fosaprepitant, granisetron, haloperidol, meclizine, methylprednisolone, metoclopramide, ondansetron, palonosetron, perphenazine, promethazine, ramosetron, rolapitant, scopolamine, and tropisetron) compared to placebo (inactive control). We performed network meta-analyses (NMAs) to estimate the relative effects and ranking (with placebo as reference) of all available single drugs and combinations. Primary outcomes were vomiting within 24 hours postoperatively, serious adverse events (SAEs), and any adverse event (AE). Secondary outcomes were drug class-specific side effects (e.g. headache), mortality, early and late vomiting, nausea, and complete response. We performed subgroup network meta-analysis with dose of drugs as a moderator variable using dose ranges based on previous consensus recommendations. We assessed certainty of evidence of NMA treatment effects for all primary outcomes and drug class-specific side effects according to GRADE (CINeMA, Confidence in Network Meta-Analysis). We restricted GRADE assessment to single drugs of direct interest compared to placebo.

MAIN RESULTS

We included 585 studies (97,516 randomized participants). Most of these studies were small (median sample size of 100); they were published between 1965 and 2017 and were primarily conducted in Asia (51%), Europe (25%), and North America (16%). Mean age of the overall population was 42 years. Most participants were women (83%), had American Society of Anesthesiologists (ASA) physical status I and II (70%), received perioperative opioids (88%), and underwent gynaecologic (32%) or gastrointestinal surgery (19%) under general anaesthesia using volatile anaesthetics (88%). In this review, 44 single drugs and 51 drug combinations were compared. Most studies investigated only single drugs (72%) and included an inactive control arm (66%). The three most investigated single drugs in this review were ondansetron (246 studies), dexamethasone (120 studies), and droperidol (97 studies). Almost all studies (89%) reported at least one efficacy outcome relevant for this review. However, only 56% reported at least one relevant safety outcome. Altogether, 157 studies (27%) were assessed as having overall low risk of bias, 101 studies (17%) overall high risk of bias, and 327 studies (56%) overall unclear risk of bias. Vomiting within 24 hours postoperatively Relative effects from NMA for vomiting within 24 hours (282 RCTs, 50,812 participants, 28 single drugs, and 36 drug combinations) suggest that 29 out of 36 drug combinations and 10 out of 28 single drugs showed a clinically important benefit (defined as the upper end of the 95% confidence interval (CI) below a risk ratio (RR) of 0.8) compared to placebo. Combinations of drugs were generally more effective than single drugs in preventing vomiting. However, single NK₁ receptor antagonists showed treatment effects similar to most of the drug combinations. High-certainty evidence suggests that the following single drugs reduce vomiting (ordered by decreasing efficacy): aprepitant (RR 0.26, 95% CI 0.18 to 0.38, high certainty, rank 3/28 of single drugs); ramosetron (RR 0.44, 95% CI 0.32 to 0.59, high certainty, rank 5/28); granisetron (RR 0.45, 95% CI 0.38 to 0.54, high certainty, rank 6/28); dexamethasone (RR 0.51, 95% CI 0.44 to 0.57, high certainty, rank 8/28); and ondansetron (RR 0.55, 95% CI 0.51 to 0.60, high certainty, rank 13/28). Moderate-certainty evidence suggests that the following single drugs probably reduce vomiting: fosaprepitant (RR 0.06, 95% CI 0.02 to 0.21, moderate certainty, rank 1/28) and droperidol (RR 0.61, 95% CI 0.54 to 0.69, moderate certainty, rank 20/28). Recommended and high doses of granisetron, dexamethasone, ondansetron, and droperidol showed clinically important benefit, but low doses showed no clinically important benefit. Aprepitant was used mainly at high doses, ramosetron at recommended doses, and fosaprepitant at doses of 150 mg (with no dose recommendation available). Frequency of SAEs Twenty-eight RCTs were included in the NMA for SAEs (10,766 participants, 13 single drugs, and eight drug combinations). The certainty of evidence for SAEs when using one of the best and most reliable anti-vomiting drugs (aprepitant, ramosetron, granisetron, dexamethasone, ondansetron, and droperidol compared to placebo) ranged from very low to low. Droperidol (RR 0.88, 95% CI 0.08 to 9.71, low certainty, rank 6/13) may reduce SAEs. We are uncertain about the effects of aprepitant (RR 1.39, 95% CI 0.26 to 7.36, very low certainty, rank 11/13), ramosetron (RR 0.89, 95% CI 0.05 to 15.74, very low certainty, rank 7/13), granisetron (RR 1.21, 95% CI 0.11 to 13.15, very low certainty, rank 10/13), dexamethasone (RR 1.16, 95% CI 0.28 to 4.85, very low certainty, rank 9/13), and ondansetron (RR 1.62, 95% CI 0.32 to 8.10, very low certainty, rank 12/13). No studies reporting SAEs were available for fosaprepitant. Frequency of any AE Sixty-one RCTs were included in the NMA for any AE (19,423 participants, 15 single drugs, and 11 drug combinations). The certainty of evidence for any AE when using one of the best and most reliable anti-vomiting drugs (aprepitant, ramosetron, granisetron, dexamethasone, ondansetron, and droperidol compared to placebo) ranged from very low to moderate. Granisetron (RR 0.92, 95% CI 0.80 to 1.05, moderate certainty, rank 7/15) probably has no or little effect on any AE. Dexamethasone (RR 0.77, 95% CI 0.55 to 1.08, low certainty, rank 2/15) and droperidol (RR 0.89, 95% CI 0.81 to 0.98, low certainty, rank 6/15) may reduce any AE. Ondansetron (RR 0.95, 95% CI 0.88 to 1.01, low certainty, rank 9/15) may have little or no effect on any AE. We are uncertain about the effects of aprepitant (RR 0.87, 95% CI 0.78 to 0.97, very low certainty, rank 3/15) and ramosetron (RR 1.00, 95% CI 0.65 to 1.54, very low certainty, rank 11/15) on any AE. No studies reporting any AE were available for fosaprepitant. Class-specific side effects For class-specific side effects (headache, constipation, wound infection, extrapyramidal symptoms, sedation, arrhythmia, and QT prolongation) of relevant substances, the certainty of evidence for the best and most reliable anti-vomiting drugs mostly ranged from very low to low. Exceptions were that ondansetron probably increases headache (RR 1.16, 95% CI 1.06 to 1.28, moderate certainty, rank 18/23) and probably reduces sedation (RR 0.87, 95% CI 0.79 to 0.96, moderate certainty, rank 5/24) compared to placebo. The latter effect is limited to recommended and high doses of ondansetron. Droperidol probably reduces headache (RR 0.76, 95% CI 0.67 to 0.86, moderate certainty, rank 5/23) compared to placebo. We have high-certainty evidence that dexamethasone (RR 1.00, 95% CI 0.91 to 1.09, high certainty, rank 16/24) has no effect on sedation compared to placebo. No studies assessed substance class-specific side effects for fosaprepitant. Direction and magnitude of network effect estimates together with level of evidence certainty are graphically summarized for all pre-defined GRADE-relevant outcomes and all drugs of direct interest compared to placebo in http://doi.org/10.5281/zenodo.4066353.

AUTHORS' CONCLUSIONS

We found high-certainty evidence that five single drugs (aprepitant, ramosetron, granisetron, dexamethasone, and ondansetron) reduce vomiting, and moderate-certainty evidence that two other single drugs (fosaprepitant and droperidol) probably reduce vomiting, compared to placebo. Four of the six substance classes (5-HT₃ receptor antagonists, D₂ receptor antagonists, NK₁ receptor antagonists, and corticosteroids) were thus represented by at least one drug with important benefit for prevention of vomiting. Combinations of drugs were generally more effective than the corresponding single drugs in preventing vomiting. NK₁ receptor antagonists were the most effective drug class and had comparable efficacy to most of the drug combinations. 5-HT₃ receptor antagonists were the best studied substance class. For most of the single drugs of direct interest, we found only very low to low certainty evidence for safety outcomes such as occurrence of SAEs, any AE, and substance class-specific side effects. Recommended and high doses of granisetron, dexamethasone, ondansetron, and droperidol were more effective than low doses for prevention of vomiting. Dose dependency of side effects was rarely found due to the limited number of studies, except for the less sedating effect of recommended and high doses of ondansetron. The results of the review are transferable mainly to patients at higher risk of nausea and vomiting (i.e. healthy women undergoing inhalational anaesthesia and receiving perioperative opioids). Overall study quality was limited, but certainty assessments of effect estimates consider this limitation. No further efficacy studies are needed as there is evidence of moderate to high certainty for seven single drugs with relevant benefit for prevention of vomiting. However, additional studies are needed to investigate potential side effects of these drugs and to examine higher-risk patient populations (e.g. individuals with diabetes and heart disease).

Management strategies for the treatment and prevention of postoperative/postdischarge nausea and vomiting: an updated review

Postoperative nausea and vomiting (PONV) and postdischarge nausea and vomiting (PDNV) remain common and distressing complications following surgery. The routine use of opioid analgesics for perioperative pain management is a major contributing factor to both PONV and PDNV after surgery. PONV and PDNV can delay discharge from the hospital or surgicenter, delay the return to normal activities of daily living after discharge home, and increase medical costs. The high incidence of PONV and PDNV has persisted despite the introduction of many new antiemetic drugs (and more aggressive use of antiemetic prophylaxis) over the last two decades as a result of growth in minimally invasive ambulatory surgery and the increased emphasis on earlier mobilization and discharge after both minor and major surgical procedures (e.g. enhanced recovery protocols). Pharmacologic management of PONV should be tailored to the patient’s risk level using the validated PONV and PDNV risk-scoring systems to encourage cost-effective practices and minimize the potential for adverse side effects due to drug interactions in the perioperative period. A combination of prophylactic antiemetic drugs with different mechanisms of action should be administered to patients with moderate to high risk of developing PONV. In addition to utilizing prophylactic antiemetic drugs, the management of perioperative pain using opioid-sparing multimodal analgesic techniques is critically important for achieving an enhanced recovery after surgery. In conclusion, the utilization of strategies to reduce the baseline risk of PONV (e.g. adequate hydration and the use of nonpharmacologic antiemetic and opioid-sparing analgesic techniques) and implementing multimodal antiemetic and analgesic regimens will reduce the likelihood of patients developing PONV and PDNV after surgery.

Chronic Atypical Antipsychotic Use Is Associated With Reduced Need for Postoperative Nausea and Vomiting Rescue in the Postanesthesia Care Unit: A Propensity-Matched Retrospective Observational Study

BACKGROUND

Atypical antipsychotics are efficacious for chemoprophylaxis against chemotherapy-induced nausea and vomiting, but perioperative investigations have been scant. We sought to examine the association between chronic atypical antipsychotic therapy and the likelihood of postoperative nausea and vomiting.

METHODS

In this single-center, propensity-matched, retrospective, observational study, elective noncardiac surgical cases from January 2014 to December 2017 were examined with regard to the primary outcome of rescue antiemetic administration in the postanesthesia care unit as a measure of postoperative nausea and vomiting. Chronic administration of olanzapine, aripiprazole, and risperidone was the exposure of interest. Other independent variables included outpatient antiemetics, modified Apfel score, age, American Society of Anesthesiologists physical status score, case length, and exposures to emetogenic and chemoprophylactic agents. Logistic regression was performed using case-level data. Conditional logistic regression was performed after 1:2 propensity matching, sampling without replacement. Monte Carlo simulation was performed to compute the mean patient-level treatment effect on the treated.

RESULTS

Of 13,660 cases, 154 cases with patients receiving atypical antipsychotics were matched against 308 cases without, representing 115 and 273 unique patients, respectively. In a well-balanced cohort, the mean patient-level odds of being administered rescue antiemetic was lower for patients chronically taking the 3 atypical antipsychotics under consideration as compared to those not on atypical antipsychotics, with an odds ratio of 0.29 (95% CI, 0.11-0.75; P = .015).

CONCLUSIONS

Chronic atypical antipsychotic therapy is associated with reduced risk of postanesthesia care unit antiemetic administration. These findings support the need for prospective studies to establish the safety and efficacy of postoperative nausea and vomiting chemoprophylaxis with these agents.

A pharmacological profile of intravenous amisulpride for the treatment of postoperative nausea and vomiting

INTRODUCTION

The issue of postoperative nausea and vomiting (PONV) remains important in surgical practice, contributing to patient distress, slower recovery, and increased use of healthcare resources. Many surgical patients report it to be a worse problem than the pain. New antiemetics of different classes are still needed to help manage PONV effectively, especially the treatment of established PONV after the failure of common prophylactic antiemetics such as 5-HT₃-antagonists and corticosteroids. Intravenous amisulpride, a drug with a long history of safe use in oral form as an antipsychotic, has recently been approved in the US (trade name: Barhemsys) as an intravenous antiemetic for the prevention and treatment of PONV.

AREAS COVERED

This review article summarizes the published data on the clinical pharmacology, safety, and efficacy of intravenous amisulpride as an antiemetic, supplemented by published data on oral amisulpride, where relevant to the intravenous form. Literature was obtained via the PubMed search terms 'intravenous amisulpride' and 'amisulpride AND safety.' Both primary and secondary pharmacology are covered, along with clinical pharmacokinetics (distribution, metabolism, and excretion). The review of clinical safety and efficacy includes data from four studies in the prevention of PONV, two in the treatment of PONV and two investigating effects on the QT interval of the electrocardiogram in healthy volunteers.

EXPERT OPINION

Given the importance of sufficient PONV prevention for patients and the healthcare system, the availability of intravenous amisulpride is helpful, restoring the dopamine-antagonist class as a potential mainstay in both combination prophylaxis and treatment.

Efficacy of amisulpride on postoperative nausea and vomiting: a systematic review and meta-analysis

AIM AND BACKGROUND

Postoperative nausea and vomiting (PONV) remains a significant clinical problem for surgical patients. Amisulpride is a well-studied D_2/D₃ antagonist that has the potential to be used for preventing and treating PONV. Our aim was to assess the efficacy and safety of amisulpride for prevention and treatment of PONV through a systematic review and meta-analysis.

METHOD

A systematic literature search was performed using MEDLINE, EMBASE, PUBMED, clinicaltrials.gov, and the Cochrane Central Register of Controlled Trials from their inception to Feb 15th, 2019. The efficacy outcome was the incidence of complete response, defined as no emesis and no rescue antiemetic use in a 24-h period after study drug administration. The safety outcomes were the adverse effects associated with amisulpride.

RESULTS

Five studies comprising 3243 patients met inclusion critieria. Compared with placebo, amisulpride showed a significantly improved incidence of complete response [relative risk (RR): 1.30; 95% confidence interval (CI): 1.20-1.41; P < 0.00001, I² = 0%] with firm evidence from the trial sequential analysis. Particularly, the amisulpride at 5 mg dose indicated a significant benefit than placebo [relative risk (RR): 1.28; 95% confidence interval (CI): 1.18-1.39; P < 0.00001, I² = 4%]. The adverse event profile of amisulpride was generally similar to the placebo.

CONCLUSION

Based on our findings, low-dose, intravenous amisulpride is safe and efficacious for the prevention and treatment of PONV compared to placebo. Further studies are needed to explore the optimal dose and timing.

CLINICAL TRIAL REGISTRATION

PROSPERO: CRD42019121483.

Metabolism and Excretion of Intravenous, Radio-Labeled Amisulpride in Healthy, Adult Volunteers

Purpose

Intravenous amisulpride, a dopamine D₂/D₃ antagonist, has recently been shown in trials to be an effective antiemetic at low doses. This study was conducted to investigate the metabolism and elimination of a single dose of intravenous ¹⁴C-labeled amisulpride in healthy, adult volunteers.

Patients and methods

Six healthy male volunteers aged 18–65 years were given a single 10 mg dose of ¹⁴C-labeled amisulpride containing not more than 1.8 MBq of radioactivity, infused over 4 mins. Concentrations of amisulpride and total radioactivity were measured in plasma, whole blood, urine and feces at various time points up to 168 hrs after dosing. Metabolites detected in plasma, urine and feces were characterized using liquid chromatography tandem mass spectrometry (LC-MS/MS) with in-line radiometric detection.

Results

The mean recovery of radioactivity in excreta was 96.4% (range 92.0–98.5%), of which 73.6% (range 70.6–79.2%) was recovered from urine and 22.8% (range 18.9–25.7%) from feces. Four metabolites of amisulpride were detected in urine, representing 15.0% of the excreted dose; three of these were also present in feces, representing 6.1% of the excreted dose. No metabolites were detected in plasma. Excretion was initially rapid, with about two-thirds of the drug-related material eliminated within 12 hrs, primarily in the urine. A second, slower phase of excretion was predominantly fecal and was essentially complete by 96 hrs after dosing. The terminal plasma elimination half-life of parent amisulpride was 3.7 hrs and that of total ¹⁴C-labeled drug material was 4.2 hrs.

Conclusion

Intravenous amisulpride undergoes limited metabolism and is excreted primarily via the renal route.

Clinical trial registry number

ClinicalTrials.gov NCT02881840.

Randomized, Double-Blind, Placebo-Controlled Study of Intravenous Amisulpride as Treatment of Established Postoperative Nausea and Vomiting in Patients Who Have Had No Prior Prophylaxis

BACKGROUND

Postoperative nausea and vomiting (PONV) occurs commonly in surgical patients despite widespread prophylactic antiemetic use. Rescue options are currently limited. 5HT3 antagonists are most frequently used for prophylaxis, but if they fail, additional doses are not effective as rescue medication. Intravenous (IV) amisulpride, a well-studied D2/D3 antagonist, has been shown in trials to prevent PONV. This study was designed to determine if amisulpride could be used to treat established PONV in patients at low-to-moderate risk of PONV who had not received any prior prophylaxis.

METHODS

Men and women aged over 18 years were permitted to enroll if they were to undergo general inhalational anesthesia, expected to last at least 1 hour, for an outpatient or inpatient surgical procedure. Patients who then suffered PONV were randomized equally to 1 of 3 single-dose IV regimens: placebo or 5 or 10 mg amisulpride. The primary end point was complete response, defined as no emesis in the period 30 minutes to 24 hours after study drug treatment and no use of rescue medication in the entire 24-hour period.

RESULTS

One thousand nine hundred eighty-eight patients were enrolled preoperatively, of whom 560 were randomized to a treatment arm. Complete response occurred in 39 of 181 patients (21.5%) in the placebo group compared to 60 of 191 patients (31.4%; P = .016) and 59 of 188 patients (31.4%; P = .016) in the amisulpride 5 and 10 mg groups, respectively. The adverse event profile of amisulpride at either dose was similar to placebo.

CONCLUSIONS

IV amisulpride at 5 and 10 mg was safe and efficacious in the treatment of established PONV in surgical patients undergoing general anesthesia with no prior PONV prophylaxis.

Clinical Use of the Pictorial Baxter Retching Faces Scale for the Measurement of Postoperative Nausea in Children

BACKGROUND

Because nausea is difficult to evaluate in children, vomiting is used as the objective clinical end point in managing pediatric postoperative nausea and vomiting and postdischarge nausea and vomiting (PDNV). The recently developed pictorial Baxter Retching Faces (BARF) scale has content, construct, and convergent validity in quantifying pediatric nausea intensity. We determined its clinical usefulness in assessing pediatric postoperative nausea and vomiting and PDNV, establishing the lowest age associated with consistently reliable use, the score at which patients identify a need for therapy, and the minimum clinically relevant change in scores, and examined its test-retest reliability.

METHODS

We obtained subject ratings of the severity of their nausea using the BARF and visual analog scales in the preoperative, postanesthesia care unit and postdischarge phases. Changes in nausea were rated on a 5-point Likert scale, along with responses to queries of a need for rescue antiemetics at these time points.

RESULTS

Children ≥6 years of age had a consistently reliable ability to use the BARF scale (132/132 [100%] vs 59/76 [77.6%] for children ≥6 and <6 years of age, respectively, Fisher exact test, P < .001). The BARF scale had excellent performance in predicting patient-perceived need for antiemetics, with a score of 4 having 80.0% sensitivity and 85.6% specificity. The minimum clinically relevant difference in BARF scores was 1.47 (95% confidence interval, 0.84-2.1). The intraclass correlation coefficient was 0.56 (95% confidence interval, 0.34-0.73).The BARF scale identified 60 of 192 (31.3%) children as having postoperative nausea in the postanesthesia care unit, with severe nausea (score >6) in 13 (6.7%). Emesis occurred in 8 (4.1%). Rescue antiemetics were administered to 16 (8.3%), including 2 with severe emesis (≥3 episodes) but in only 2 of 11 (18.2%) with severe nausea without vomiting. PDNV was reported in 39 of the 99 who returned diaries (39.4%), with nausea in 34 (34.3%), severe nausea in 15 (15.2 %), and emesis in 16 (16.2%).

CONCLUSIONS

The pictorial BARF scale is easy to use in the clinical setting by children ≥6 years of age, has a minimum clinically relevant difference of 1.47, with scores of 4 or higher associated with a patient-identified need for rescue antiemetics. Assessment of postoperative nausea by the BARF scale has shown that clinically significant nausea occurs frequently in children but is not always treated unless accompanied by vomiting.

The latest consensus on antiemetics

PURPOSE OF REVIEW

The present review summarizes and discuss the most recent updated antiemetic consensus.

RECENT FINDINGS

Two new neurokinin (NK)1-receptor antagonists, netupitant and rolapitant, have been approved by the Food and Drug Administration and the European Medicines Agency and incorporated in the latest versions of the MASCC/ESMO, ASCO, and NCCN guidelines. Guidelines all recommend a combination of a serotonin (5-HT)3-receptor antagonist, dexamethasone, and a NK1-receptor antagonist in patients receiving highly emetogenic chemotherapy (HEC) with the addition of the multireceptor targeting agent, olanzapine, as an option in cisplatin or anthracycline-cyclophosphamide chemotherapy. A combination of a 5-HT3-receptor antagonist, dexamethasone, and a NK1-receptor antagonist is also recommended in patients receiving carboplatin-based chemotherapy, although based on a lower level of evidence. In spite of the development of new antiemetics, nausea has remained a significant adverse effect. Olanzapine is an effective antinausea agent, but sedation can be a problem. Therefore, the effect and tolerability of multitargeting, nonsedative agents like amisulpride, should be explored.

SUMMARY

Guidelines recommend a combination of a 5-HT3-receptor antagonist, dexamethasone, and an NK1-receptor antagonist in HEC and carboplatin-based chemotherapy. The addition of olanzapine can be useful in cisplatin-based and anthracycline-cyclophosphamide-based chemotherapy in particular if the main problem is nausea.

Amisulpride for the Rescue Treatment of Postoperative Nausea or Vomiting in Patients Failing Prophylaxis

Editor’s Perspective

What We Already Know about This Topic

What This Article Tells Us That Is New

Background

Although antiemetics are commonly used to prevent postoperative nausea or vomiting, the failure rate is appreciable and there is currently no generally accepted standard for rescue treatment of postoperative nausea or vomiting after failed prophylaxis. This prospective, randomized, double-blind, parallel-group, placebo-controlled, multicenter study was designed to test the hypothesis that intravenous amisulpride, a dopamine D2/D3-antagonist, is superior to placebo at treating established postoperative nausea or vomiting after failed prophylaxis.

Methods

A total of 2,285 adult patients undergoing surgery under general inhalational anesthesia and receiving standard antiemetic prophylaxis were enrolled at 23 sites in Canada, France, Germany, and the United States. Of these, 702 patients experienced postoperative nausea or vomiting in the 24-h period after surgery and were randomized to receive a single dose of 5 or 10 mg intravenous amisulpride or matching placebo. The primary endpoint was complete response, defined as no emesis or rescue antiemetic use for 24 h after study drug administration, excluding emesis in the first 30 min. Secondary endpoints included incidence of emesis and rescue medication use, nausea burden, time to treatment failure, and length of stay in postanesthesia care unit and hospital.

Results

Complete response occurred in significantly more patients receiving 10 mg amisulpride (96 of 230, 41.7%) than placebo (67 of 235, 28.5%), a 13.2% difference (95% CI, 4.6 to 21.8; odds ratio, 1.80; P = 0.006). A 5-mg dose of amisulpride did not show a significant benefit (80 of 237, 33.8%); the difference from placebo was 5.2% (95% CI, 3.1 to 13.6; odds ratio, 1.24; P = 0.109). The total number of adverse events recorded and proportion of patients with at least one adverse event were comparable between the placebo and amisulpride groups. No clinically relevant toxicities were observed.

Conclusions

A single 10-mg dose of intravenous amisulpride was safe and more effective than placebo at treating established postoperative nausea or vomiting in patients failing postoperative nausea or vomiting prophylaxis.

What is new in the battle against postoperative nausea and vomiting?

The issue of postoperative nausea and vomiting (PONV) still poses a significant burden on our patients. Although rarely associated with a life-threatening condition, it is consistently considered as one of the most undesirable side effects of surgery and anesthesia. There are well-established risk factors for the development of PONV that include patient-related factors, anesthetic technique, use of volatile anesthetics, use of nitrous oxide, duration of anesthesia, opioid administration, and type of surgery. Because pharmacologic interventions for PONV are not without risks, practitioners must assess patient's risk status from low to high and consider the benefits of treatment. This review summarizes the current state of knowledge related to PONV and provides a practical approach toward risk assessment, prevention, and numerous treatment strategies.