Association between droperidol use and sudden death in two patients intoxicated with illicit stimulant drugs

Illicit drug intoxication is often a cause of extreme agitation in the emergency department and prehospital settings. Chemical restraint is often required to protect patient as well as health-care providers. Droperidol has commonly been used to sedate extremely agitated patients in the emergency department and psychiatric settings. Its safety has been demonstrated in these settings and in patients who's agitation has been attributed to amphetamine toxicity. We present 2 cases of sudden death following the use of droperidol to sedate 1 patient who was extremely agitated secondary to cocaine intoxication and another secondary to phencyclidine intoxication.

Comparison of the depressive effects of four anesthetic regimens on ventilatory and cardiovascular variables in the guinea pig

BACKGROUND AND PURPOSE

Guinea pigs are one of the most difficult rodents to anesthetize safely, and as a consequence, there is a paucity of reports regarding the effects of anesthesia on their cardiorespiratory variables. We used long-term indwelling cannulas for studying the guinea pig in the conscious state, and subsequently investigated the effects of four types of injectable anesthetic regimens on cardiorespiratory variables.

METHODS

Using barometric plethysmography (conscious: long-term cannulated, n = 11; no cannulation, n = 28) or trachea-out plethysmography (anesthetized: n = 7 for each of the four groups), we recorded ventilatory, cardiovascular, metabolic, and arterial gas variables during air breathing and in response to 10 min of hypoxia (8% O2) and 10 min of hypercapnia (8% CO2). The four anesthetic regimens tested were: Saffan (infused at 9.75 mg/kg of body weight/h, i.v.); ketamine/xylazine (14.6/3.7 mg/kg/h, i.v.); pentobarbitone (8.3 mg/kg/h, i.v.) plus Innovar Vet (0.15 mg/kg every 1 to 1.5 h, s.c.); or pentobarbitone alone (22 mg/kg/h, i.v.).

RESULTS

The least depressive anesthetic with regard to ventilation (VE) was ketamine/xylazine. Air breathing was depressed by only 17% (cf approx 50 to 60% for all other regimes), and the VE responses to hypoxia and hypercapnia were attenuated the least. All anesthetics equally depressed mean arterial blood pressure (from 70 mmHg to 56 mmHg) and ketamine/xylazine was the only anesthetic to reduce heart rate (from 260 beats/min to 198 beats/min).

CONCLUSION

Although all anesthetics induce cardiorespiratory depression to some extent, the use of ketamine/ xylazine is recommended for future use in respiratory studies of the guinea pig where anesthesia cannot be avoided.

Unexpected cardiovascular deaths are rare with therapeutic doses of droperidol

In December 2001, the FDA required a "black box warning" suggesting that unexpected cardiovascular deaths could occur at normal therapeutic doses of droperidol. We reviewed data from 270 MedWatch reports, including 99 reports of death, submitted between November 1, 1997, and January 10, 2002. We further reviewed primary reports of deaths and cardiovascular adverse events associated with < or = 10 mg of droperidol. There were 99 death reports representing 89 patients, with a specified dose in 66 cases. Among 74 (83%) foreign fatality reports, 57 included a known dose (> or = 50 mg in 29 cases [49%] and < or = 2.5 mg in only 3 cases [5%]). Of the 15 (17%) U.S. cases, 9 included a specified dose (< or = 2.5 mg in 5 cases and 5-10 mg in 4 cases). Cardiovascular deaths after therapeutic doses (< or = 2.5 mg) of droperidol are rare. Mandatory electrocardiographic screening appears unnecessary.

The antiemetic efficacy of droperidol added to morphine patient-controlled analgesia: a randomized, controlled, multicenter dose-finding study

The antiemetic dose response of droperidol when it is added to patient-controlled analgesia with morphine is not well known. We randomly allocated adults who received postoperative morphine patient-controlled analgesia (1-mg bolus, 5-min lockout) to one of four regimens: no droperidol (control) or 5, 15, or 50 micro g of droperidol per milligram of morphine. Efficacy and adverse effects were recorded during 24 h and were analyzed with number needed to treat (NNT) and number needed to harm with 95% confidence intervals. Data from 82 controls, 82 patients receiving droperidol 5 micro g, 82 receiving droperidol 15 micro g, and 83 receiving droperidol 50 micro g were analyzed. Average consumption of droperidol per 24 h was 0.2 mg with the 5- micro g regimen, 0.61 mg with the 15- micro g regimen, and 2.04 mg with the 50- micro g regimen. In controls, the incidence of nausea was 48.8%; with droperidol 5 micro g, it was 42.7% (NNT compared with control, 16 [95% confidence interval, 4.7 to -11]); with 15 micro g, it was 32.9% (NNT, 6.3 [3.3-100]); and with 50 micro g, it was 21.7% (NNT, 3.7 [2.4 to 7.6]). In controls, the incidence of vomiting was 24.4%; with droperidol 5 micro g, it was 23.2% (NNT compared with control, 82 [7 to -8.5]); with 15 micro g, it was 22.0% (NNT, 41 [6.5 to -9.6]); and with 50 micro g, it was 12% (NNT, 8.1 [4.2-142]). In controls, the incidence of pruritus was 12.2%; with droperidol 5 micro g, it was 6.1% (NNT compared with control, 16 [6.7 to -37]); and with 15 and 50 micro g, it was 2.4% (NNT, 10 [5.7-52]). In controls, the incidence of sedation was 2.4%; with droperidol 5 micro g, it was 8.5% (number needed to harm (NNH) compared with control, 16 [7.7 to -123]); with 15 micro g, it was 6.1% (NNH, 27 [10 to -40]); and with 50 micro g, it was 18.1% (NNH, 6.4 [4.1-15]). There were no extrapyramidal symptoms and no cardiac adverse events. There was no difference in patient satisfaction. The optimal antiemetic dose of droperidol is 15-50 micro g/mg of morphine. Larger doses may have more antivomiting efficacy but are likely to be unacceptably sedating.

Droperidol in the emergency department: is it safe?

Droperidol is an antipsychotic and antiemetic drug that has been used extensively by emergency physicians, psychiatrists, and anesthesiologists worldwide since 1967. It also has been used effectively for other diverse conditions, such as treatment of headache and vertigo. As of January 2001, Droperidol was no longer available in Europe after its founder, Janssen-Cilag Pharmaceuticals, discontinued its distribution. In December 2001, the United States Food and Drug Administration (FDA) placed a black box warning on the use of Droperidol in response to an association between Droperidol and fatal cardiac dysrhythmias, such as torsade de pointes, resulting from prolongation of the QT interval. In this review we closely examine the pharmacology, indications, use, and complications associated with Droperidol, and speculate on its future use in the Emergency Department.

A review of the safety and efficacy of droperidol for the rapid sedation of severely agitated and violent patients

BACKGROUND

Droperidol had become a standard treatment for sedating severely agitated or violent patients in both psychiatric and medical emergency departments. However, several recent articles have suggested that droperidol may have a quinidine-like effect similar to that of thioridazine in inducing dysrhythmia.

METHOD

In view of the recent U.S. Food and Drug Administration (FDA) position regarding the use of thioridazine, the authors reviewed the literature regarding droperidol and dysrhythmia in a MEDLINE search for the years 1960-2002 using the search terms droperidol, dysrhythmia, QTc interval, and sudden death as well as their own experience in using droperidol in a busy psychiatric emergency department. This review was done before the FDA's very recent and peremptory warning about droperidol.

RESULTS

The authors report that, in treating approximately 12,000 patients over the past decade, they have never experienced a clinically significant adverse dysrhythmic event using droperidol to sedate severely agitated or violent patients.

CONCLUSION

The authors conclude that, in clinical practice, droperidol is an extremely effective and safe method for treating severely agitated or violent patients. While in theory droperidol may prolong the QT interval to an extent similar to thioridazine, in clinical use there is no pattern of sudden deaths analogous to those that provoked the FDA warning about thioridazine.

Droperidol, QT prolongation, and sudden death: what is the evidence?

STUDY OBJECTIVE

Droperidol is a butyrophenone commonly used as an antiemetic and antipsychotic in the United States since US Food and Drug Administration (FDA) approval in 1970. Its labeling has recently been revised, with a black box warning for cases of QT prolongation leading to torsades de pointes and death. A black box warning is applied when serious adverse drug reactions are uncovered for medications. We sought to examine the evidence of a causal association suggested by the black box warning to aid clinicians in their risk-benefit analyses regarding further use of droperidol.

METHODS

A literature search was undertaken to determine the evidence regarding the association between droperidol and QT prolongation or torsades de pointes. The evidence was then evaluated by using evidence-based medicine principles. In addition, a review of the FDA regulatory process is presented.

RESULTS

Three clinical studies, 1 published abstract, and 7 case reports were reviewed. Available postmarketing surveillance data (MedWatch reports) were also reviewed. Applying the criteria of evidence-based medicine and Hill's criteria, the evidence is not convincing for a causal relationship between therapeutic droperidol administration and life-threatening cardiac events.

CONCLUSION

The recent black box warning appears to have originated from postmarketing surveillance data rather than data reported in the peer-reviewed medical literature. Ongoing monitoring of drug safety and more definitive study appear appropriate.

The addition of droperidol or clonidine to epidural tramadol shortens onset time and increases duration of postoperative analgesia

PURPOSE

To compare tramadol alone and the combinations of either tramadol-clonidine or tramadol-droperidol with regard to analgesic and adverse effects.

METHODS

After Ethic's Committee approval and patient informed consent were obtained, epidural catheters were inserted preoperatively at the L(3-4) interspace in 90 ASA physical status I-II adult patients undergoing lower abdominal surgery. Anesthesia was standardized. Patients were randomly assigned to one of three groups. Group I (T) patients received tramadol 75 mg, Group II (TD) patients received tramadol 75 mg plus droperidol 2.5 mg, and Group III (TC) patients received tramadol 75 mg plus clonidine 150 microg in a total volume of 10 mL administered as a single epidural injection in the postanesthesia care unit. The onset time of analgesia and duration of analgesia, visual analogue pain scores, sedation, nausea scores, vital signs and side effects were recorded.

RESULTS

Duration of analgesia was similar in both the TD and TC groups, and significantly longer than in the T group (P < 0.001). Group TC patients displayed a significant increase in sedation scores and decrease in blood pressure and heart rate when compared with other groups (P < 0.001). No adverse effects were observed in Group TD, while nausea scores were high in both the T and TC groups (P < 0.001). Pain score, respiration rate, and SpO(2) values were similar in all study groups.

CONCLUSION

We conclude that epidural tramadol in combination with droperidol or clonidine prolongs the duration of analgesia; however, droperidol appears to be a better alternative when adverse effects and antiemetic properties are taken into consideration.