Meta-analysis of the safety of 5-HT3 antagonists with dexamethasone or droperidol for prevention of PONV

BACKGROUND

Antiemetic guidelines recommend a combination of serotonin (5-HT3) with a second agent such as droperidol or dexamethasone. Physicians have been reluctant to employ these guidelines due to concerns over the black-box warning of droperidol and safety concerns with a steroid.

OBJECTIVE

To assess the safety profiles of 5-HT3 receptor antagonist (5-HT3RA) monotherapy and combination therapy with a steroid or droperidol for prophylaxis of postoperative nausea and vomiting (PONV).

METHODS

A MEDLINE search of English-language reports of randomized controlled trials (RCTs) was conducted (1966-September 2005) using the key terms 5-HT3, granisetron, ondansetron, dolasetron, tropisetron, PONV, postoperative, vomiting, emesis, and nausea. RCTs with treatment arms comparing 5-HT3RA monotherapy (granisetron, ondansetron, dolasetron, or tropisetron) with dexamethasone or droperidol or 5-HT3RA combinations and providing incidence data on adverse events were identified and reviewed. Within-study odds ratios with 95% confidence intervals were calculated to determine the incidence rates of all adverse events in RCTs using 5-HT3RA monotherapy and combination therapies. Overall effect sizes for frequently reported adverse events were estimated by pooling ORs using fixed- and random-effect models.

RESULTS

Pooled ORs (OR(pooled)) for adverse events with 5-HT3RA/dexamethasone versus 5-HT3RA for PONV prophylaxis were not significant for any reported adverse events or the overall incidence of adverse events; 5-HT3RA/droperidol versus 5-HT3RA was significant only for decreased headache incidence (fixed model: OR(pooled) 0.35; 95% CI 0.18 to 0.69). The OR(pooled) for 5-HT3RA/dexamethasone versus dexamethasone was not significant for any reported adverse events except headaches (fixed model OR(pooled) 1.75; 95% CI 1.01 to 3.03), none of which was serious. OR(pooled) for 5-HT3RA/droperidol versus droperidol was not significant for any reported adverse events. Avascular necrosis, occult infection, and delayed wound healing were not observed with either combination therapy. Cardiac abnormalities were observed with 5-HT3RA/droperidol therapy.

CONCLUSIONS

This meta-analysis indicates that either therapy has a safety profile similar to that of dexamethasone, droperidol, or 5-HT3RA.

Droperidol’s Effect on QT Interval

The Food and Drug Administration (FDA) issued a letter to health care providers on December 4, 2001, concerning the medication, droperidol. The purpose of the warning was to alert health care providers to the possible role of droperidol in the development of torsades de pointes (TdP) in susceptible patients. The purpose of this article is to explore the role of droperidol in the development of TdP in susceptible patients and current recommendations for the use of droperidol as an antiemetic.

Antipruritic and antiemetic effect of epidural droperidol

BACKGROUND AND OBJECTIVES

This study was designed to investigate whether single epidural droperidol or continuous epidural droperidol inhibit pruritus and postoperative nausea and vomiting induced by postoperative continuous epidural fentanyl administration, and to identify the optimal method of administering epidural droperidol.

METHODS

120 ASA I-II patients undergoing subtotal gastrectomy with general anaesthesia combined with epidural anaesthesia were randomly allocated into three groups: control (no droperidol), single injection (droperidol 2.5 mg) and continuous group (droperidol 2.5 mg 2 day(-1)). Postoperatively the frequency and severity of pruritus and postoperative nausea and vomiting in all groups were compared during 48 h.

RESULTS

The frequency and severity of pruritus was significantly lower in both single injection and continuous groups than control group after epidural fentanyl administration (P < 0.05). The frequency and severity of postoperative nausea and vomiting was significantly lower in single injection group than control group after epidural fentanyl administration (P < 0.05).

CONCLUSION

Epidural continuous droperidol is effective for reducing pruritus, and single epidural droperidol injection is effective for reducing pruritus and postoperative nausea and vomiting induced by postoperative continuous epidural fentanyl analgesia.

Randomized Clinical Trial Comparing Intravenous Midazolam and Droperidol for Sedation of the Acutely Agitated Patient in the Emergency Department

STUDY OBJECTIVE

We compare intravenous midazolam and droperidol for the onset of sedation of acutely agitated patients in the emergency department (ED).

METHODS

This was a double-blind, randomized, clinical trial set in the ED of a university teaching hospital. Subjects were adults, acutely agitated because of mental illness, intoxication, or both, who received midazolam or droperidol, 5 mg intravenously, every 5 minutes until sedated. We analyzed time to sedation using survival analysis, median times to sedation, and proportions sedated at 5 and 10 minutes.

RESULTS

Seventy-four patients received midazolam; 79 patients, droperidol. Survival analysis showed no difference in time to sedation (hazard ratio 0.86; 95% confidence interval [CI] 0.61 to 1.23), P=.42. Median time to sedation was 6.5 minutes for midazolam (median dose 5 mg) and 8 minutes for droperidol (median dose 10 mg), P=.075 (effect size 1.5 minutes; 95% CI 0 to 4 minutes). At 5 minutes, 33 of 74 (44.6%) patients from the midazolam group were adequately sedated compared with 13 of 79 (16.5%) patients from the droperidol group, a difference of 28.1% (95% CI 12.9% to 43.4%; P<.001). By 10 minutes, 41 of 74 (55.4%) from the midazolam group were sedated compared to 42 of 79 (53.2%) from droperidol, a difference of 2.2% (95% CI -14.9% to 19.3%; P=.91). Eleven adverse events occurred in the midazolam group and 10 in the droperidol group. Three patients required active airway management (3 patients with assisted ventilation and 1 patient intubated); all received midazolam.

CONCLUSION

There is no difference in onset of adequate sedation of agitated patients using midazolam or droperidol. Patients sedated with midazolam may have an increased need for active airway management.

Interaction between tramadol and two anti-emetics on nociception and gastrointestinal transit in mice

BACKGROUND

Clinical studies suggest that tramadol-induced analgesia is partially antagonized by ondansetron.

AIMS

To investigate the type of interaction between tramadol and two anti-emetics on antinociception and gastrointestinal transit in mice.

METHODS

We assessed the antinociceptive (acetic acid writhing test, plantar test) and antitransit (charcoal meal) effects of tramadol individually, and combined with ondansetron or droperidol in female Swiss CD-1 mice. Isobolograms and analysis of variance were used to determine the type of interaction.

RESULTS

In the writhing test, tramadol, ondansetron and droperidol, each induced dose-related inhibition of nociception. The ED(50)'s were: tramadol 4.2+/-0.33 mg kg(-1); ondansetron 1.03+/-0.05 mg kg(-1), and droperidol 1.00+/-0.14 mg kg(-1). Dose-response curves were also obtained with tramadol combined with ondansetron or droperidol at 1:1 fixed ratios. The isobolographic analysis demonstrated antagonism for both combinations. In the plantar test, the ED(50) for tramadol was 51.4+/-2.3 mg kg(-1), but no dose-response curves could be obtained with ondansetron or droperidol individually. The interaction was assessed from dose-response curves to tramadol in the presence of a fixed dose of ondansetron (0.1 mg kg(-1)) or droperidol (0.05 mg kg(-1)). The results show antagonism between tramadol-ondansetron (p<0.05) and no interaction for the tramadol-droperidol combination. Both anti-emetics antagonized the antitransit effects of tramadol.

CONCLUSIONS

The interaction of tramadol with ondansetron or droperidol on antinociception can be antagonistic or additive, depending on the type of stimuli. Both anti-emetics antagonize the anti-transit effects of tramadol. The results demonstrate antagonism between tramadol and the two anti-emetics for analgesia and inhibition of gastrointestinal transit, supporting previous clinical studies.

Haloperidol: an alternative butyrophenone for nausea and vomiting prophylaxis in anesthesia

Droperidol has been an efficacious, inexpensive butyrophenone used since the early 1970s to prevent or treat postoperative nausea and vomiting. Because of reports of sudden cardiac death in patients receiving droperidol, the US Food and Drug Administration (FDA) recently placed significant restrictions on its administration. These restrictions have essentially removed droperidol from use. Haloperidol is another butyrophenone with antiemetic properties but without the FDA restrictions. This article reviews the literature regarding haloperidol and supports its use as a safe substitute for droperidol in the prevention and treatment of postoperative nausea and vomiting.

[Four cases of extrapyramidal reactions to epidural droperidol administration]

Continuous epidural administration of droperidol at 2.5 mg x day(-1) or less was performed in 837 patients after surgery. In 4 of these patients, an extrapyramidal reaction occurred. Patient 1 was a 10-year-old girl who developed the symptom 29 hours after the start of administration, with a total dose of 3.0 mg. Patient 2 was a 16-year-old girl in whom the symptom occurred 24 hours after the start, with a total of 5.3 mg. Patient 3 was a 22-year-old female with the symptom occurring 26 hours after the start, with a total of 5.2 mg. Patient 4 was a 74-year-old female in whom the symptom occurred 24 hours after the start, with a total of 1.3 mg. With respect to the age distribution, the total of 837 patients consisted of 16 patients aged 10 to 19 years, 85 patients aged 20 to 29 years, 91 patients aged 30 to 39 years, 90 patients aged 40 to 49 years, 77 patients aged 50 to 59 years, 148 patients aged 60 to 69 years, 240 patients aged 70 to 79 years, 97 patients aged 80 to 89 years, and 9 patients aged 90 to 99 years. Extrapyramidal reactions related to epidural administration may readily develop at younger ages.

Prolongation of QTc interval after postoperative nausea and vomiting treatment by droperidol or ondansetron

BACKGROUND

At dosages above 0.1 mg/kg, droperidol induces a dose-dependent QTc interval prolongation. Although subject to controversy, low-dose droperidol has recently been suspected to induce cardiac arrhythmias. Hence, 5-hydroxytryptamine type 3 antagonists have become the first-line drug for management of postoperative nausea and vomiting. These drugs are also known to prolong the QTc interval at high dosages. This study describes QTc interval changes associated with postoperative nausea and vomiting treatment by droperidol or ondansetron at low doses.

METHODS

Eighty-five patients with postoperative nausea and vomiting were included in this prospective, single-blind study. Patients received either 0.75 mg intravenous droperidol (n = 43) or 4 mg intravenous ondansetron (n = 42). Electrocardiographic recordings were obtained before administration of antiemetic drug and then 1, 2, 3, 5, 10, and 15 min after. Electrocardiographic monitoring was maintained for 3 h in eight patients in each group.

RESULTS

The QTc interval was prolonged (> 450 ms in men, > 470 ms in women) in 21% of the patients before antiemetic drug administration. This was significantly correlated with lower body temperature and longer duration of anesthesia. Compared with predrug QTc measurement, both antiemetics were associated with a significant QTc interval prolongation (P < 0.0001). The mean maximal QTc interval prolongation was 17 +/- 9 ms after droperidol occurring at the second minute and 20 +/- 13 ms after ondansetron at the third minute (both P < 0.0001). Compared with predrug measurement, the QTc interval was significantly lower after the 90th minute in both groups.

CONCLUSIONS

Droperidol and ondansetron induced similar clinically relevant QTc interval prolongations. When used in treatment of postoperative nausea and vomiting, a situation where prolongation of the QTc interval seems to occur, the safety of 5-hydroxytryptamine type 3 antagonists may not be superior to that of low-dose droperidol.

Morphine sparing with droperidol in patient-controlled analgesia

STUDY OBJECTIVE

To determine if droperidol has a morphine-sparing effect when coadministered with morphine via patient-controlled analgesia (PCA) for postoperative pain management.

DESIGN

A randomized, double-blind clinical study.

SETTING

Department of Anesthesiology, Kaohsiung Veterans General Hospital, Taiwan.

PATIENTS

One hundred seventy-nine American Society of Anesthesiologists physical status 1 and 2 female patients undergoing abdominal hysterectomy.

INTERVENTIONS

At the end of surgery, patients in the droperidol group received PCA, with the device programmed to deliver a bolus dose of 1 mg morphine and 50 mug droperidol on demand. Patients in the control group received 1 mg morphine on demand. For both groups, PCA lockout was 5 minutes between boluses, with a 4-hour morphine limit of 30 mg.

MEASUREMENTS AND MAIN RESULTS

Pain intensity at rest or on movement and relative sedation score were evaluated and recorded at 6, 12, 24, 48, and 72 hours after surgery. Related side effects were also evaluated and recorded on postoperative days 1, 2, and 3. Morphine use was significantly lower for the droperidol group than the control group during the postoperative 72-hour period (33.9 +/- 9.8 and 54.9 +/- 12.1 mg, respectively), with significantly decreased pain intensity levels for the former relative to the latter at 48 hours (pain intensity on movement: 3.9 +/- 1.2 vs 4.3 +/- 0.9, respectively; P = .049) and 72 hours (pain intensity on movement: 3.0 +/- 1.1 vs 3.6 +/- 0.5, respectively; P = .003; pain intensity at rest: 1.3 +/- 1.0 vs 1.6 +/- 0.7, respectively; P = .033) subsequent to surgery. Control subjects demonstrated a greater frequency of postoperative nausea and vomiting than did their droperidol counterparts on postoperative day 1.

CONCLUSION

Coadministration of 50 mug droperidol and 1 mg morphine on demand via PCA provides a morphine-sparing effect and reduces the frequency of postoperative nausea and vomiting.

Effect of Low-dose Droperidol on the QT Interval during and after General Anesthesia

Background

Since the effects of antiemetic doses of droperidol on the QT interval have not been previously studied, the authors designed a randomized, double-blind, placebo-controlled study to evaluate the intraoperative and postoperative effects of small-dose droperidol (0.625 and 1.25 mg intravenous) on the QT interval when used for antiemetic prophylaxis during general anesthesia.

Methods

One hundred twenty outpatients undergoing otolaryngologic procedures with a standardized general anesthetic technique were enrolled in this study. After anesthetic induction and before the surgical incision, 60 patients were given either saline or 0.625 or 1.25 mg intravenous droperidol in a total volume of 2 ml. A standard electrocardiographic lead II was recorded immediately before and every minute after the injection of the study medication during a 10-min observation period. The QTc (QT interval corrected for heart rate) was evaluated from the recorded electrocardiographic strips. In 60 additional patients, a 12-lead electrocardiogram was obtained before and at specific intervals up to 2 h after surgery to assess the effects of droperidol and general anesthesia on the QTc. Any abnormal heartbeats or arrhythmias during the operation or the subsequent 2-h monitoring interval were also noted.

Results

Intravenous droperidol, 0.625 and 1.25 mg, prolonged the QT interval by an average of 15 +/- 40 and 22 +/- 41 ms, respectively, at 3-6 min after administration during general anesthesia, but these changes did not differ significantly from that seen with saline (12 +/- 35 ms) (all values mean +/- SD). There were no statistically significant differences among the three study groups in the number of patients with greater than 10% prolongation in QTc (vs. baseline). Although general anesthesia was associated with a 14- to 16-ms prolongation of the QTc interval in the early postoperative period, there was no evidence of droperidol-induced QTc prolongation after surgery. Finally, there were no ectopic heartbeats observed on any of the electrocardiographic rhythm strips or 12-lead recordings during the perioperative period.

Conclusion

Use of a small dose of droperidol (0.625-1.25 mg intravenous) for antiemetic prophylaxis during general anesthesia was not associated with a statistically significant increase in the QTc interval compared with saline. More importantly, there was no evidence of any droperidol-induced QTc prolongation immediately after surgery.

Safety of droperidol in behavioural emergencies

By the year 2000, droperidol had become a standard drug for the treatment of behavioural emergencies in both psychiatric and medical settings. In 2001, the US FDA issued a 'black box' warning, citing cases of QT prolongation and/or torsades de pointes. As a result, the use of droperidol has been sharply circumscribed. The authors will review the literature on antipsychotic medications in general, focusing on droperidol in particular, with regard to QT interval prolongation, dysrhythmia, and sudden death. In addition, the mechanism of drug-induced QT interval prolongation will be discussed. The authors will then review their extensive experience with droperidol. The authors conclude that, while in theory droperidol may prolong the QT interval to an extent similar to thioridazine, its long history of clinical use has shown no pattern of sudden deaths analogous to those that provoked the FDA warning. Although the numbers presented by the FDA initially appear alarming, after further evaluation it is clear that more definitive studies should have been carried out. Droperidol is safe, extremely effective, and now underused as a treatment for severely agitated or violent patients.

The efficacy of the 5-HT3 receptor antagonists combined with droperidol for PONV prophylaxis is similar to their combination with dexamethasone. A meta-analysis of randomized controlled trials

PURPOSE

The aim of this quantitative systematic review is to compare the efficacy and side effects of combining one of the 5-HT(3) receptor antagonists (5-HT) with droperidol or dexamethasone for postoperative nausea and vomiting (PONV) prophylaxis.

METHODS

We performed a systematic search (Medline, Embase, and the Cochrane Library) for randomized controlled trials that compared the antiemetic efficacy of combining one of the 5-HT with droperidol or dexamethasone vs 5-HT alone. Relevant endpoints were prevention of early (0 to 6 hr), and overall (0 to 24 hr) PONV, and side effects. The articles that could meet the inclusion criteria were scored for inclusion and methodological validity using the three-item, five-point, Oxford-scale. Relative risk and numbers needed-to-treat with 95% confidence intervals were calculated for each combination vs 5-HT alone. The two combinations were then indirectly compared. A random effects model was used.

RESULTS

We considered 41 trials for analysis but subsequently excluded eight. Thirty-three trials with data from 3,447 patients were analyzed. Except for early nausea with the 5-HT plus droperidol, both combinations were significantly more effective than 5-HT in preventing early and overall PONV. There was no difference in antiemetic efficacy between the two combinations. The incidence of commonly reported side effects was also similar in the two combination groups.

CONCLUSION

We conclude that there is no statistically significant difference in antiemetic efficacy or side effects profile when one of the 5-HT is combined with either droperidol or dexamethasone and that both combination regimens are significantly more effective than 5-HT alone.

Droperidol for perioperative sedation causes a transient prolongation of the QTc time in children under volatile anesthesia

BACKGROUND

Droperidol is useful for postoperative sedation in infants and children after cardiac surgery because it provides sedation and akinesia with minimal respiratory depression. However, droperidol has been associated with QT prolongation and ventricular arrhythmias. We investigated, if neuroleptanalgesic doses of droperidol led to QT prolongation and cardiac arrhythmias in children undergoing cardiac surgery.

METHODS

We retrospectively analysed electrocardiogram rhythm strips that were obtained before and in time increments after a 100 microg x kg(-1) intravenous bolus of droperidol in 20 children undergoing cardiac surgery. The longest QT interval was determined in each ECG and corrected for heart rate (QTc). All arrhythmias were recorded.

RESULTS

Droperidol led to a significant increase in QTc time that was still present at 15 min but had resolved within 30 min after the bolus. No associated arrhythmias were observed.

CONCLUSIONS

The statistically significant prolongation of QTc time after a sedative dose of droperidol is of concern because it may increase the risk for malignant cardiac arrhythmias. A large, prospective study is necessary to identify the true risk for arrhythmias after droperidol in this patient population, but our study suggests that any arrhythmogenic risk, if present, will be very transient, since the increase in QTc time was limited to a period of less than 30 min after the bolus.

Droperidol and dolasetron alone or in combination for prevention of postoperative nausea and vomiting after vitrectomy

PURPOSE

Droperidol and the new serotonin-3 antagonists are effective drugs for the prophylaxis of postoperative nausea and vomiting (PONV). The aim of this trial was to evaluate whether dolasetron could be a substitute for droperidol, because the Food and Drug Administration has required a Black Box warning on the droperidol package insert.

DESIGN

Randomized, placebo-controlled, double-blinded trial.

PARTICIPANTS

Inpatients undergoing vitreoretinal surgery (standard 3-port pars plana vitrectomy for proliferative diabetic vitreoretinopathy, complicated retinal detachment, or macular disease, such as macular pucker, macular hole, or choroidal neovascularization).

INTERVENTION

Two hundred forty patients (3x80) receiving droperidol (10 microg. kg(-1)), dolasetron (12.5 mg), or the combination of both drugs administered 5 to 10 minutes before the end of surgery.

CONTROL

Eighty patients received saline placebos as controls.

METHODS

Standardized general anesthesia was performed, including benzodiazepine premedication, propofol, atracurium or vecuronium, desflurane in N(2)O/O(2), and a continuous infusion of remifentanil. Postoperative analgesia and antiemetic rescue medication were standardized. Episodes of vomiting, retching, nausea, and the need for additional antiemetics were recorded for 24 hours.

MAIN OUTCOME MEASURES

Severity of PONV (rated by a standardized scoring algorithm) was analyzed as the main end point of the study using the Kruskal-Wallis test.

RESULTS

Data of 304 patients could be analyzed. Mean severity scores in the placebo, dolasetron, droperidol, and combination groups were 1.21, 0.76, 0.47, and 0.30. Incidences of PONV of any severity were 56%, 40%, 28%, and 18%, respectively. The reduction of the incidence of PONV and its severity was statistically significant in the droperidol group and in the combination group relative to the placebo. Dolasetron alone failed to reduce the incidence of PONV. The combination of dolasetron and droperidol showed an additive antiemetic efficacy.

CONCLUSION

Low-dose droperidol (10 microg. kg(-1)) but not dolasetron (12.5 mg) reduced postoperative nausea and vomiting after vitreoretinal surgery. Dolasetron (12.5 mg) is not an equivalent substitute for droperidol.

Effects of droperidol dosage on postoperative emetic symptoms following pediatric strabismus surgery

STUDY OBJECTIVE

To compare the frequency of postoperative emetic symptoms and side effects in pediatric strabismus surgery using four doses of droperidol.

DESIGN

Randomized, blinded study.

SETTING

University eye institute.

PATIENTS

82 ASA physical status I and II pediatric patients, aged 1 to 16 years, undergoing outpatient strabismus surgery.

INTERVENTIONS

Patients were assigned to one of four doses of droperidol (10, 20, 40, or 80 microg.kg(-1)) (Groups 1, 2, 3, and 4, respectively). All patients received the same anesthetic management, with droperidol administered intravenously immediately after induction of anesthesia.

MEASUREMENTS AND MAIN RESULTS

Postoperatively, patients were evaluated for emetic symptoms (nausea, retching, and/or vomiting) and side effects (postoperative sedation or extrapyramidal symptoms). There was a dose-dependent reduction of emetic symptoms seen with increasing droperidol dose. Predischarge emetic symptoms were 50%, 15%, 15%, and 5% in Groups 1, 2, 3, and 4, respectively (p < 0.009). Peak emetic symptoms were observed after discharge: 75%, 40%, 35%, and 15% in Groups 1, 2, 3, and 4, respectively (p < 0.003). Convalescence times, including awakening, extubation, recovery, and hospitalization, were unaffected by increasing droperidol dose. Sedation was similar in all groups and no patient exhibited any side effects. However, when patients exhibited emetic symptoms, discharge time increased from 207 +/- 57 minutes to 283 +/- 128 minutes (p < 0.001).

CONCLUSIONS

Prophylactic administration of droperidol 80 microg.kg(-1) is most effective in reducing postoperative emetic symptoms without increasing time to discharge. In those patients with emetic symptoms who also received prophylactic droperidol, time to discharge was significantly delayed.

Randomized, double-blind trial of dolasetron versus droperidol for prophylaxis of postoperative nausea and vomiting in patients undergoing TRAM flap breast reconstruction surgery

Clinical observation indicates that patients undergoing transverse rectus abdominus musculocutaneous (TRAM) flap breast reconstruction surgery frequently experience postoperative nausea and/or vomiting (PONV). No controlled trials have evaluated the role of pharmacologic prophylaxis of PONV in this population. A prospective randomized, double-blinded, active-controlled trial comparing intraoperative intravenous droperidol 1 mg with dolasetron 50 mg was conducted. Seventy-one patients were included in the intention-to-treat analysis. The incidence of the primary end point of PONV within 24 hours after surgery was 81.8% versus 78.9% for droperidol and dolasetron, respectively (p = 0.8). No significant differences were detected in the time to onset of PONV, incidence of severe nausea or emesis, or incidence of emesis alone. Time to rescue antiemetic use was longer in the droperidol group (7.1 vs. 1.3 hours, p = 0.002). Adverse effects were similar between the two groups. No PONV-related complications occurred during the trial period. The incidence of PONV in TRAM flap breast reconstruction surgery patients remains high despite prophylactic intraoperative antiemetic administration.