The antiemetic effectiveness of droperidol during morphine patient-controlled analgesia

Quetiapine and other antipsychotics combined with opioids in legal autopsy cases: A random finding or cause of fatal outcome?

Opioid poisoning is a frequent cause of death in drug addicts and occurs with opioid treatment. Quetiapine is often found in forensic autopsies and may increase the risk of fatal opioid poisoning by enhancing sedation, respiratory depression, hypotension and QT prolongation. We systematically searched for studies of acute toxicity of quetiapine or other antipsychotics combined with morphine or methadone. Case reports describing toxicity of quetiapine combined with morphine or methadone were also included. We retrieved one human study that observed pharmacokinetic interaction between quetiapine and methadone, and 16 other human studies. Fourteen investigated the combination of droperidol and morphine in treatment doses, and some indicated an additive sedative effect. Five animal studies with acepromazine in combination with morphine or methadone were located and indicated an additive effect on sedation and hypotension. Six forensic case reports in which death could have been caused solely by quetiapine, the opioid, or other drugs were found. Thus, acute toxicity of quetiapine combined with morphine or methadone has not been studied. Because of quetiapine's effects on alpha-adrenoceptors, muscarinic and histamine receptors, human ether-a-go-go-channels and methadone kinetics, we suggest further research to clarify if the indicated additive effects of opioids and droperidol or acepromazine are also true for quetiapine.

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).

WITHDRAWN: Drugs for preventing postoperative nausea and vomiting

BACKGROUND

Drugs can prevent postoperative nausea and vomiting, but their relative efficacies and side effects have not been compared within one systematic review.

OBJECTIVES

The objective of this review was to assess the prevention of postoperative nausea and vomiting by drugs and the development of any side effects.

SEARCH METHODS

We searched The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2, 2004), MEDLINE (January 1966 to May 2004), EMBASE (January 1985 to May 2004), CINAHL (1982 to May 2004), AMED (1985 to May 2004), SIGLE (to May 2004), ISI WOS (to May 2004), LILAC (to May 2004) and INGENTA bibliographies.

SELECTION CRITERIA

We included randomized controlled trials that compared a drug with placebo or another drug, or compared doses or timing of administration, that reported postoperative nausea or vomiting as an outcome.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted outcome data.

MAIN RESULTS

We included 737 studies involving 103,237 people. Compared to placebo, eight drugs prevented postoperative nausea and vomiting: droperidol, metoclopramide, ondansetron, tropisetron, dolasetron, dexamethasone, cyclizine and granisetron. Publication bias makes evidence for differences among these drugs unreliable. The relative risks (RR) versus placebo varied between 0.60 and 0.80, depending upon the drug and outcome. Evidence for side effects was sparse: droperidol was sedative (RR 1.32) and headache was more common after ondansetron (RR 1.16).

AUTHORS' CONCLUSIONS

Either nausea or vomiting is reported to affect, at most, 80 out of 100 people after surgery. If all 100 of these people are given one of the listed drugs, about 28 would benefit and 72 would not. Nausea and vomiting are usually less common and, therefore, drugs are less useful. For 100 people, of whom 30 would vomit or feel sick after surgery if given placebo, 10 people would benefit from a drug and 90 would not. Between one to five patients out of every 100 people may experience a mild side effect, such as sedation or headache, when given an antiemetic drug. Collaborative research should focus on determining whether antiemetic drugs cause more severe, probably rare, side effects. Further comparison of the antiemetic effect of one drug versus another is not a research priority.

Drugs for preventing postoperative nausea and vomiting

BACKGROUND

Drugs can prevent postoperative nausea and vomiting, but their relative efficacies and side effects have not been compared within one systematic review.

OBJECTIVES

The objective of this review was to assess the prevention of postoperative nausea and vomiting by drugs and the development of any side effects.

SEARCH STRATEGY

We searched The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2, 2004), MEDLINE (January 1966 to May 2004), EMBASE (January 1985 to May 2004), CINAHL (1982 to May 2004), AMED (1985 to May 2004), SIGLE (to May 2004), ISI WOS (to May 2004), LILAC (to May 2004) and INGENTA bibliographies.

SELECTION CRITERIA

We included randomized controlled trials that compared a drug with placebo or another drug, or compared doses or timing of administration, that reported postoperative nausea or vomiting as an outcome.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted outcome data.

MAIN RESULTS

We included 737 studies involving 103,237 people. Compared to placebo, eight drugs prevented postoperative nausea and vomiting: droperidol, metoclopramide, ondansetron, tropisetron, dolasetron, dexamethasone, cyclizine and granisetron. Publication bias makes evidence for differences among these drugs unreliable. The relative risks (RR) versus placebo varied between 0.60 and 0.80, depending upon the drug and outcome. Evidence for side effects was sparse: droperidol was sedative (RR 1.32) and headache was more common after ondansetron (RR 1.16).

AUTHORS' CONCLUSIONS

Either nausea or vomiting is reported to affect, at most, 80 out of 100 people after surgery. If all 100 of these people are given one of the listed drugs, about 28 would benefit and 72 would not. Nausea and vomiting are usually less common and, therefore, drugs are less useful. For 100 people, of whom 30 would vomit or feel sick after surgery if given placebo, 10 people would benefit from a drug and 90 would not. Between one to five patients out of every 100 people may experience a mild side effect, such as sedation or headache, when given an antiemetic drug. Collaborative research should focus on determining whether antiemetic drugs cause more severe, probably rare, side effects. Further comparison of the antiemetic effect of one drug versus another is not a research priority.

A dose ranging study of dexamethasone for preventing patient-controlled analgesia-related nausea and vomiting: a comparison of droperidol with saline

We designed this study to determine the minimum dose of dexamethasone for preventing nausea and vomiting associated with the use of morphine by patient-controlled analgesia (PCA). Two hundred forty female patients were randomly assigned to receive dexamethasone 2, 4, 8, or 12 mg IV immediately before induction of anesthesia. Droperidol (0.1 mg/mL with morphine 1 mg/mL in PCA pump) and saline were used as controls. The complete response (no postoperative nausea and vomiting and no need for rescue antiemetic for a 24-h postoperative period) rates for dexamethasone 8 mg (72.2%) and 12 mg (78.9%) were significantly more than for saline (42.9%) (P < 0.05). Patients who received dexamethasone 12 or 8 mg also reported higher patient satisfaction than those who received saline (P < 0.05). These results were as effective as adding droperidol 0.1 mg/mL to the morphine PCA without causing drowsiness, restlessness, or arrhythmias. Smaller doses of dexamethasone (4 or 2 mg) were not effective for this propose. The results suggest that dexamethasone 8 mg IV is the minimum effective dose for the reduction of PCA morphine-related nausea and vomiting.

IMPLICATIONS

Morphine administration by patient-controlled analgesia (PCA) is often associated nausea and vomiting. In this double-blind study, the minimum effective dose of dexamethasone for reducing this complication was 8 mg. This was as effective as adding droperidol 0.1 mg/mL to the morphine PCA without causing drowsiness, restlessness or arrhythmias.

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.

Prophylactic ondansetron does not improve patient satisfaction in women using PCA after Caesarean section

Eighty-one consenting women undergoing elective Caesarean section under spinal anaesthesia were randomly divided into two groups. In Group O patients, ondansetron 4 mg was given intravenously at the end of the surgery and 8 mg added to the morphine solution in the PCA syringe. Patients in Group P received only morphine via PCA syringe. Analgesia and nausea were measured until PCA was discontinued 24 h after the operation. Women in the two groups were similar with respect to age, duration of use of the PCA, amount of morphine used, previous history of PONV, and incidence of motion sickness and morning sickness during the current pregnancy. The number of women who complained of nausea and those needing rescue antiemetic medication was significantly less in Group O. However, there was no statistically significant difference between the two groups in the patient's perception of the control of nausea and their overall satisfaction. It was noted that PONV was more frequent among women who had significant morning sickness during early pregnancy and ondansetron was beneficial in reducing PONV in these women. Although the ondansetron reduced the incidence of PONV and the need for further antiemetic medication, this did not affect patient's satisfaction regarding their postoperative care.

Patient-controlled analgesia and postoperative nausea and vomiting: efficacy of a continuous infusion of ondansetron

A continuous infusion of ondansetron was compared with a placebo infusion in 80 patients undergoing major breast reconstructive surgery. All patients received a standard anaesthetic and a bolus dose of ondansetron after induction. They were then randomly allocated to receive an intravenous infusion of ondansetron or a placebo infusion for 24 h in a double-blind fashion. Postoperative analgesia was provided by patient-controlled subcutaneous diamorphine. In the ondansetron group, the severity of nausea, measured by a 10-point verbal rating scale, was reduced (p = 0.01) and fewer patients stated at postoperative interview that nausea and vomiting was a problem (p = 0.01).

A comparison of papaveretum-promethazine with morphine-ondansetron for patient-controlled analgesia

BACKGROUND

Patient-controlled analgesia (PCA) with intravenous morphine is commonplace. Antiemetics are often added to reduce side-effects. In our institution an unusual combination of papaveretum-promethazine is in use.

AIMS

We set out to compare this combination with a more commonly used one (morphine-ondansetron) by auditing the records of our pain-control team assessing analgesia and control of side-effects.

METHODS

The records of two groups of 100 consecutive patients were studied. Pain scores were recorded 24 hours post-operatively on a scale of zero to ten. Also recorded were sedation scores, pruritus, emesis, and usage of breakthrough analgesia. The groups contained the work of a variety of anaesthetists and surgeons, though the majority were orthopaedic cases. All results were recorded by one pain-control nurse, using the same question, over a nine-month period.

RESULTS

Sedation scores were identical, while side-effects were few and similar in both groups. The use of breakthrough analgesia was also similar. However, the median pain-score of zero in the papaveretum group was significantly lower than that of two in the morphine group, (p < 0.001, Mann-Whitney U).

CONCLUSION

Papaveretum-promethazine appeared to be effective for PCA. This combination is also much less expensive than morphine-ondansetron. A previously described synergistic interaction between promethazine and opiates may be a factor in its success. Further evaluation of these drugs in PCA is warranted.

Prevention of postoperative nausea and vomiting in gynaecological laparotomies: a comparison of tropisetron and ondansetron

In a randomized, double-blind study, the antiemetic efficacy of a single bolus of tropisetron 5 mg (group T, 37 patients), ondansetron 4 mg (group O, 39 patients) or saline (group C, 45 patients) given at induction was compared in a homogeneous group of 121 patients undergoing gynaecological laparotomy and receiving postoperative patient-controlled intravenous morphine for 24 to 48 hours. Fewer group T and group O patients developed severe nausea compared to group C (P < 0.01, log rank test in Kaplan-Meier analysis). Group T patients also had lower nausea scores than group O at 8 to 16h (P < 0.05). The overall incidences of severe nausea in groups T, O, and C were 5.4%, 17.9%, and 44.4% respectively (P < 0.001, group T vs group C; P < 0.05 group O vs group C). In conclusion, the 5-hydroxytryptamine 3 receptor antagonists tropisetron and ondansetron were superior to placebo in preventing PONV.

Efficacy and adverse effects of prophylactic antiemetics during patient-controlled analgesia therapy: a quantitative systematic review

Nausea and vomiting are frequent adverse effects of patient-controlled analgesia (PCA) with opioids. To identify the optimal prophylactic antiemetic intervention in this setting, we performed a systematic search for randomized trials (MEDLINE, EMBASE, Cochrane library, reference lists, hand-searching, no language restriction) published up to May 1998 that compared prophylactic antiemetic interventions with placebo or no treatment in the postoperative PCA-setting with opioids. Fourteen placebo-controlled trials (1117 patients) with different regimens of droperidol, ondansetron, hyoscine TTS, tropisetron, metoclopramide, propofol, and promethazine were analyzed. One PCA was with tramadol, all others were with morphine. At 24 h, the cumulative incidence of nausea and vomiting without antiemetics was approximately 50%. Droperidol 0.017-0.17 mg/mg of morphine (0.5-11 mg/d droperidol) was statistically significantly more effective than placebo without evidence of dose-responsiveness; the number needed to treat to prevent nausea compared with placebo was 2.7 (95% confidence interval 1.8-5.2), and that to prevent vomiting was 3.1 (2.3-4.8). Compared with placebo, the incidence of minor adverse effects with droperidol was increased with doses >4 mg/d.

IMPLICATIONS

Of 100 patients treated with droperidol added in a patient-controlled analgesia pump with morphine, 30 who would have vomited or been nauseated had they not received droperidol will not suffer these effects. There is no evidence of dose-responsiveness for efficacy with droperidol, but the risk of adverse effects is dose-dependent. There is a lack of evidence for other antiemetics.

[Patient-controlled analgesia. Benefits, risks, methods of monitoring]

Patient-controlled analgesia refers to a relatively new approach to morphine delivery in which patients are allowed to self-administer small doses of an opioid, to achieve adequate relief of postoperative pain. The main benefit is to reduce fluctuations in opioid plasma concentrations. A matter for worry remains the occurrence of side effects, especially ventilatory depression. In order to guarantee the efficacy and safety of this technique, the education of patients and nurses is essential. Protocols are required, specifying the use of this technique (prescription, patient monitoring, treatment of side effects).

A comparison of prophylactic ondansetron hydrochloride and droperidol for strabismus repair in adults

BACKGROUND

Prophylactic administration of an antiemetic is a common procedure for patients undergoing strabismus surgery. Droperidol and ondansetron hydrochloride are commonly used antiemetics. This study compared the rates of postoperative nausea and vomiting (PONV) in adult patients undergoing strabismus surgery with prophylactically administered Droperidol or ondansetron hydrochloride.

METHODS

A double-masked, randomized, prospective study was conducted comparing droperidol with ondansetron hydrochloride when administered prophylactically to adults undergoing strabismus surgery.

RESULTS

Forty-five patients entered the study with a mean age of 30 years. Twenty percent of patients had nausea immediately postoperatively and 37% had nausea before discharge with no significant differences between groups. Overall rate of emesis, time in the recovery room, and time to discharge was not significantly different between the droperidol and ondansetron hydrochloride group.

CONCLUSION

No real differences in the ability to prevent PONV between the two medications were found in this study.

Epidural infusion of bupivacaine 0.0625% plus fentanyl 3.3 micrograms/ml provides better postoperative analgesia than patient-controlled analgesia with intravenous morphine after gynaecological laparotomy

One hundred and twenty women undergoing gynaecological abdominal operations were randomized to receive either epidural bupivacaine 0.0625% + fentanyl 3.3 micrograms/ml infusion (Group EPI, n = 57), or patient-controlled intravenous morphine analgesia (Group PCA, n = 54) for postoperative pain relief. The groups were comparable in demographic data, types and duration of operation. Group EPI achieved significantly lower verbal rating scale of pain (VRS) at rest at 0, 4, 12, 16, 20, 28 and 40th postoperative hours. The VRS during cough were also significantly lower in Group EPI at 0, 4, 8, 12, 28 and 36th postoperative hours. None of the patients had respiratory depression or hypotension. Nausea/vomiting occurred in 52.6%/33.3% of patients in Group EPI and 52.7%/37.0% in Group PCA. Most patients (84.2% in Group EPI and 72.2% in Group PCA) rated their pain management as "good". We conclude that epidural infusion of bupivacaine 0.0625% and fentanyl 3.3 micrograms/ml provide better analgesia than patient-controlled intravenous morphine after gynaecological laparotomy.

Comparison of tramadol and tramadol/droperidol mixture for patient-controlled analgesia

PURPOSE

To compare the analgesic efficacy and side effects of tramadol vs tramadol and droperidol for post-operative patient-controlled analgesia (PCA).

METHODS

Randomised, double-blind study. Thirty-four patients undergoing elective colorectal or head and neck surgery were allocated to Group 1 (n = 18, PCA bolus 10 mg tramadol) or Group 2 (n = 16, PCA bolus 10 mg tramadol + 0.1 mg droperidol). Anaesthesia was induced with fentanyl and thiopentone and maintained with O2, N2O plus enflurane or isoflurane with iv morphine at doses decided by the attending anaesthetists. Muscle relaxation was achieved with atracurium or vecuronium. Patients were observed four-hourly for pain using an 11-point verbal rating scale (VRS). Nausea and vomiting, and sedation were assessed using four-point scales post-operatively. Vital signs, request for rescue anti-emetic and analgesic, and overall satisfaction were recorded.

RESULTS

The mean nausea scores were lower in Group 2 (1.00 +/- 1.33 vs 0.06 +/- 0.25 at 0-8 hr, 1.22 +/- 1.93 vs 0.06 +/- 0.25 at 8-16 hr, P < 0.01; 0.81 +/- 1.68 vs 0 at 32-40 hr, P < 0.05; Group 1 vs Group 2). The vomiting scores were also lower (0.50 +/- 1.04 vs 0 at 0-8 hr, 0.67 +/- 1.50 vs 0, at 8-16 hr, P < 0.05; Group 1 vs Group 2). Seven (39%) patients in Group 1, but none in Group 2 requested rescue anti-emetic (P < 0.01). There were no differences in VRS, sedation score, overall satisfaction or vital signs.

CONCLUSION

Tramadol and droperidol combination is superior to tramadol alone for post-operative PCA. It provides a similar quality of analgesia with less nausea and vomiting and without an increase in sedation.

The prevention of postoperative nausea and vomiting using a combination of ondansetron and droperidol

We have studied the effect of combination antiemetic therapy (ondansetron and droperidol) with morphine delivered by patient-controlled analgesia following major gynaecological surgery. Sixty patients were randomly allocated to one of three treatment regimens; ondansetron alone (4 mg bolus and 0.13 mg.ml-1 in the morphine solution), droperidol alone (1.25 mg bolus and 0.05 mg.ml-1 in the morphine solution), or both drugs in combination. For the first 12 postoperative hours, patients receiving combination therapy experienced significantly less nausea than those receiving single antiemetic therapy (p < 0.001). There was no difference between the regimens from 12 to 18 h. We conclude that a combination of ondansetron and droperidol added to morphine in a patient-controlled analgesia system reduces postoperative nausea to a greater extent than treatment with either drug alone following major gynaecological surgery.