Ondansetron versus placebo for the control of nausea and vomiting during Caesarean section under spinal anaesthesia

This prospective, randomised, placebo-controlled, double-blind study was performed to evaluate the effects of ondansetron on nausea and vomiting during elective Caesarean section under spinal anaesthesia. Seventy-four full-term parturients were studied. After umbilical-cord clamping, ondansetron 4 mg or 0.9% saline was injected intravenously and the study period continued for 2 h. The severity of nausea was graded from 0 = none to 10 = maximum, while that of vomiting was graded from single = once per min to continuous = multiple per min. The incidence of vomiting was lower following ondansetron (36%) compared with the control group (58%, p < 0.028). Neither the severity of vomiting nor the incidence of nausea was influenced by ondansetron. However, for those who experienced nausea, ondansetron reduced its severity (p = 0.05). We conclude that the intra-operative administration of 4 mg ondansetron intravenously during Caesarean section under spinal anaesthesia significantly reduces the incidence of vomiting and the severity of nausea.     

Rapid improvement in post-infectious gastroparesis symptoms with mirtazapine

We report the case of a 34-year-old woman with severe post-infectious gastroparesis who was transferred from an outside medical facility for a second opinion regarding management.This patient had no prior history of gastrointestinal symptoms.However,in the aftermath of a viral illness,she developed two months of intractable nausea,vomiting,and oral intake intolerance that resulted in numerous hospitalizations for dehydration and electrolyte disturbances.A solid-phase gastric emptying scan had confirmed delayed emptying,confirming gastroparesis.Unfortunately,conventional pro-kinetic agents and numerous anti-emetic drugs provided little or no relief of the patient’s symptoms.At our institution,the patient experienced a cessation of vomiting,reported a significant reduction in nausea,and toler-ated oral intake shortly after taking mirtazapine.Based on mirtazapine’s primary action as a serotonin(5-HT)1a receptor agonist,we infer that this receptor system mediated the clinical improvement through a combination of peripheral and central neural mechanisms.This report highlights the potential utility of 5-HT1a agonists in the management of nausea and vomiting.We conclude that mirtazapine may be effective in treating symptoms associated with non-diabetic gastroparesis that are refractory to conventional therapies.     

Comparison of cyclizine and ondansetron for the prevention of postoperative nausea and vomiting in laparoscopic day-case gynaecological surgery

Seventy-four patients undergoing laparoscopic gynaecological surgery were randomly allocated to two groups receiving cyclizine 50 mg or ondansetron 4 mg at induction of anaesthesia. Anaesthetic and postoperative analgesia regimens were standardised. Approximately half of the patients in each group experienced some degree of postoperative nausea and vomiting (cyclizine, 56%; ondansetron, 54%). There was no difference between groups in respect of pre- and postdischarge incidence. Mean (SD) time to eye opening was significantly prolonged in the cyclizine group [10 (4) min vs. 8 (2) min; p < 0.001], but this had no influence on discharge times. Cyclizine and ondansetron appear equally effective in preventing postoperative nausea and vomiting but the 10-fold price differential favours cyclizine.     

Inconsistency of prognostic factors for post-chemotherapy nausea and vomiting

A number of prognostic factors have been reported to influence the probability of developing nausea and vomiting after cytotoxic chemotherapy. This study used data collected in four randomized anti-emetic trials conducted by the Clinical Trials Group of the National Cancer Institute of Canada (NCIC-CTG) to assess the consistency of the effects of these prognostic factors. A total of 582 patients, all of whom had received moderately emetogenic chemotherapy for the first time, but who were assigned to different anti-emetics, were included in the analysis. The major findings was that the probability of post-chemotherapy nausea and vomiting was much more strongly influenced by the type of chemotherapy given and the type of anti-emetic used than by patient (e.g., age, gender) or environmental (e.g., treatment location, time of administration) characteristics. Further, patient-related factors had different, and sometimes opposite, effects in different anti-emetic and chemotherapy subgroups. Finally, the relative potency of anti-emetics appeared to vary with chemotherapy regimens. Implications of these findings for future studies are discussed.     

Analysis of two treatment modalities for the prevention of vomiting after trauma: Orogastric tube or anti-emetics

IntroductionVomiting in the emergency department after trauma occurs frequently and might lead to aspiration of gastric content. An orogastric tube (OGT) is a way to prevent emesis. However, this is an inconvenient procedure and may actually trigger vomiting. Therefore, a change in policy was applied from preferably an OGT to the administration of anti-emetics in a selected population. The aim of this study was to analyse the prevention of vomiting in trauma patients after OGT or anti-emetics.Materials and methodsRetrospective cohort study. Data of all trauma patients presented at the crash room of the emergency department between July 1st 2013 and July 1st 2014 were collected from the local trauma registry and electronic patient documentation system and comprising 6 months preceding and 6 months after change of policy. Vomiting and nausea after trauma were recorded. Furthermore, complications such as aspiration and cardiac arrhythmias were documented.ResultsA total of 1446 patients were presented after trauma. 230 patients were promptly intubated. An additional 763 patients were fully responsive and did not complain of nausea. The remaining 453 patients were further analysed. 44 patients received OGT placement procedure and 409 patients received anti-emetics. Significant difference was found in patients vomiting after OGT placement or anti-emetics (20.5% vs. 2.7%; P < 0.001). Patients who received anti-emetics were not more at risk for cardiac arrhythmias. After matched control analysis, there was still a significant difference was found.Discussion and conclusionAdministration of anti-emetics is suitable and effective for the prevention of vomiting after trauma in this selected population, without an increased risk for complications.     

The effect of dexamethasone upon patient-controlled analgesia-related nausea and vomiting

Ninety female patients were enrolled in this randomised, double-blind, placebo-controlled study to compare the anti-emetic effect of intravenous dexamethasone 8 mg with saline control in preventing patient-controlled analgesia-related nausea and vomiting following major orthopaedic surgery. The prophylactic administration of dexamethasone 8 mg significantly reduced the overall incidence of patient-controlled analgesia-related nausea and vomiting (p<0.001) and the need for rescue anti-emetics (p<0.01). Furthermore, patients who received dexamethasone showed a higher incidence of complete responses (no vomiting or need for rescue anti-emetic for a 24-h postoperative period) than those who received saline (p<0.05). We conclude that dexamethasone 8 mg may be valuable for preventing patient-controlled analgesia-related nausea and vomiting in women undergoing major orthopaedic surgery.     

Side effects of anti-emetics: results of a class experiment

A number of standard anti-emetic drugs (perphenazine, promethazine, propiomazine, thiethylperazine, hyoscine, cyclizine, dimenhydrinate, metoclopramide) and a placebo were given by intramuscular injection to students in a clinical pharmacology class to allow them to study side effects. Students proved to be sensitive detectors of the subjective side effects and the placebo response rate was low. Drowsiness was the commonest and most marked side effect; the extra-pyramidal effects were confined to the phenothiaziness, and dizziness and dryness of mouth were frequent only after hyoscine. Cardiovascular effects were trivial and only slight bradycardia was noted with all substances administered. The undesired actions of the phenothiazines lasted longer than those of cyclizine and hyoscine. The frequency of side-effects of anti-emetic drugs is so high that they must be balanced against efficacy in choosing an anti-emetic for a particular situation.     

Postoperative nausea and vomiting

Postoperative nausea and vomiting (PONV) remains a common clinical problem that increases healthcare costs and affects patient satisfaction and morbidity. This article outlines the physiology, reviews the available drugs and suggests a structure using risk stratification that helps to plan sensible clinical management.