Pro: The Food and Drug Administration Black box warning on droperidol is not justified

Postoperative/postdischarge nausea and vomiting: evidence-based prevention and treatment

PURPOSE OF REVIEW

Postoperative/postdischarge nausea and vomiting (PONV/PDNV) remains a relevant issue in perioperative care. Especially in outpatient surgery, PONV can prevent discharge or lead to unplanned readmission.

RECENT FINDINGS

Evidence on prophylaxis and treatment of PONV is growing, but implementation remains poor.

SUMMARY

A liberal, universal PONV management is now endorsed by the guidelines. Specific evidence concerning prevention and (at-home) treatment of PDNV is still scarce.

Delayed Ventricular Tachycardia After Prophylactic Doses of Droperidol in Patients With Mild QT Interval Prolongation Due to Preoperative Medication

Prophylactic doses of droperidol are effective in preventing postoperative nausea and vomiting (PONV). However, due to concerns of QT interval prolongation and ventricular arrhythmias, the safety of droperidol for PONV prophylaxis has been debated.

A 70-year-old woman was scheduled for total knee arthroplasty. She had a history of aortic valve replacement. Oral aprindine (40 mg/day) was prescribed. Preoperative electrocardiogram showed mild QT interval prolongation (QTc = 475 ms). Anesthesia was induced using propofol, remifentanil, and rocuronium, and maintained using desflurane, remifentanil, and a bolus dose of rocuronium.

The surgery was uneventful. At the time of skin closure, droperidol (1.25 mg) was administered intravenously for PONV prophylaxis. Twenty-three minutes after administration of droperidol, a sudden onset of premature cardiac contraction was observed, which progressed directly to ventricular tachycardia and atrioventricular block. Arrhythmia due to droperidol-induced QT interval prolongation was strongly suspected. Intravenous magnesium sulfate (2 g) and atropine (0.5 mg) were administered immediately. The ventricular tachycardia resolved quickly after the magnesium injection. Following the resolution of the arrhythmia, the patient was extubated.

The patient experienced ventricular tachycardia after a prophylactic dose of droperidol that resulted from QT interval prolongation due to the preoperative medication. It may be prudent to avoid even low-dose droperidol in the background of already present QT prolongation, especially when multiple putative QT-prolonging drugs are used.

Anesthesia Management and Postanesthetic Recovery Following Endoscopic Sinus Surgery

OBJECTIVES

Delayed anesthesia recovery following endoscopic sinus surgery (ESS) can be an indicator of immediate complications and negatively impact healthcare efficiency. This study aims to examine clinical factors with a focus on improving clinical practice.

METHODS

Medical records of patients undergoing ESS under general anesthesia from 2014 to 2018 were reviewed. Based on the interquartile range of anesthesia recovery for the cohort, patients in the upper quartile were categorized as "prolonged" and the lowest three quartiles as "goal" recovery. Patient and surgical characteristics were investigated.

RESULTS

Analyzing 416 patients who underwent ESS, the median anesthesia recovery time was 48 [35-66] minutes. Prolonged recovery was associated with higher body mass index (odds ratio 1.50 [95% confidence interval 1.03-2.18] per 10 kg/m² , P = .03) and surgical duration (1.37 [1.10-1.72] per hour, P < .01). Inversely, goal recovery was associated with preoperative acetaminophen (0.61 [0.38-0.98], P = .04) and intraoperative remifentanil (0.55 [0.32-0.93], P = .03). Patients with prolonged recovery had higher rates of severe pain (33 (31.7%) vs. 25 (8.0%), P < .01), respiratory depression (7 [6.7] vs. 2 [0.6], P < .01), oversedation (39 [37.5] vs. 39 [12.5], P < .01), and the need for rescue opioids (52 [50] vs. 71 [22.8], P < .01). In addition to reduced postanesthesia recovery time, patients who were administered preemptive acetaminophen had lower rates of severe pain (OR 0.55 [0.31-0.98], P = .04) and nausea and vomiting (0.39 [0.17-0.87], P = .02).

CONCLUSION

Our findings substantiate the use of acetaminophen and remifentanil in ESS, facilitating anesthesia recovery. Broadly consideration of preemptive acetaminophen could further increase postoperative comfort in ESS.

LEVEL OF EVIDENCE

4 - Retrospective. Laryngoscope, 131:E815-E820, 2021.

The Incidence of QT Prolongation and Torsades des Pointes in Patients Receiving Droperidol in an Urban Emergency Department

INTRODUCTION

Droperidol carries a boxed warning from the United States Food and Drug Administration for QT prolongation and torsades des pointes (TdP). After a six-year hiatus, droperidol again became widely available in the US in early 2019. With its return, clinicians must again make decisions regarding the boxed warning. Thus, the objective of this study was to report the incidence of QT prolongation or TdP in patients receiving droperidol in the ED.

METHODS

Patients receiving droperidol at an urban Level I trauma center from 1997-2001 were identified via electronic health record query. All patients were reviewed for cardiac arrest. We reviewed electrocardiogram (ECG) data for both critically-ill and noncritical patients and recorded Bazett's corrected QT intervals (QTc). ECGs from critically-ill patients undergoing resuscitation were further risk-stratified using the QT nomogram.

RESULTS

Of noncritical patients, 15,374 received 18,020 doses of droperidol; 2,431 had an ECG. In patients with ECGs before and after droperidol, the mean QTc was 424.3 milliseconds (ms) (95% confidence interval [CI], 419.7-428.9) before and 427.6 ms (95% CI, 424.3-430.9), after droperidol (n = 170). Regarding critically-ill patients, 1,172 received droperidol and 396 had an ECG. In the critically-ill group with ECGs before and after droperidol mean QTc was 435.7 ms (95% CI, 426.7-444.7) before and 435.8 ms (95% CI, 427.5-444.1) after droperidol (n = 114). Of 337 ECGs suitable for plotting on the QT nomogram, 13 (3.8%) were above the "at-risk" line; 3/136 (2.2%; 95% CI, 0.05-6.3%) in the before group, and 10/202 (4.9%; 95% CI, 2.4%-8.9%) in the after group. A single case of TdP occurred in a patient with multiple risk factors that did not reoccur after a droperidol rechallenge. Thus, the incidence of TdP was 1/16,546 (0.006%; 95% CI, 0.00015 - 0.03367%).

CONCLUSION

We found the incidence of QTc prolongation and TdP in ED patients receiving droperidol to be extremely rare. Our data suggest the FDA "black box warning" is overstated, and that close ECG monitoring is useful only in high-risk patients.

Evidence-based review and appraisal of the use of droperidol in the emergency department

Droperidol is a short-acting, potent dopamine D2 antagonist that can pass through the blood-brain barrier. A black box warning was issued for droperidol by the United States Food and Drug Administration in 2001 because of a risk of development of torsades de pointes induced by QT prolongation. Many experts feel that the incidence of arrhythmia is overestimated, and low-dose droperidol is almost always used by anesthesiologists for postoperative nausea and vomiting. In this review, we used evidence-based analysis to appraise high-quality studies with a low risk of bias published after 2001 on the use of droperidol in the emergency department (ED). Droperidol appears not only efficacious but also safe to treat patients with nausea/vomiting, acute psychosis, and migraine in the ED. For these conditions, droperidol may be an option for shared decision-making.

Small doses of droperidol do not present relevant torsadogenic actions: a double-blind, ondansetron-controlled study

AIM

Drugs used for postoperative nausea and vomiting prophylaxis are believed to provoke torsadogenic changes in cardiac repolarization. The aim of this study was to assess the effect of small doses of droperidol on the parameters of cardiac repolarization, including the QTc interval and transmural dispersion of repolarization.

METHODS

A total of 75 patients were randomly allocated to receive 0.625 or 1.25 mg droperidol or 8 mg ondansetron. The QTc interval was calculated using Bazett's formula and the Framingham correction. The transmural dispersion of repolarization was determined as Tpeak -Tend time.

RESULTS

Transient QT prolongation, corrected with both formulae, followed 1.25 mg of droperidol 10 min after administration. No change in the QTc value was observed in the other groups. When corrected with Bazett's formula, QTc was prolonged above 480 ms in two patients receiving 1.25 mg droperidol (at the 10(th) and 20(th) minute of the study) and in one receiving ondansetron. No patients developed a QTc B prolongation over 500 ms. No increase above 480 ms was observed relative to the Framingham correction method. There were no significant differences in the Tpeak -Tend time either between or within the groups.

CONCLUSION

In men without cardiovascular disorders small doses (1.25 mg) of droperidol prophylaxis induced transient QTc prolongation without changes in transmural dispersion of repolarization. The apparently low risk of the drug applies only in low risk male patients with a low pro-QTc score.

Droperidol for treatment of nausea and vomiting in palliative care patients

BACKGROUND

This is an updated version of the original Cochrane review published in Issue 10, 2010, on droperidol for the treatment of nausea and vomiting in palliative care patients. Nausea and vomiting are common symptoms in patients with terminal illness and can be very unpleasant and distressing. There are several different types of antiemetic treatments that can be used to control these symptoms. Droperidol is an antipsychotic drug and has been used and studied as an antiemetic in the management of postoperative and chemotherapy nausea and vomiting.

OBJECTIVES

To evaluate the efficacy and adverse events (both minor and serious) associated with the use of droperidol for the treatment of nausea and vomiting in palliative care patients.

SEARCH METHODS

We searched electronic databases including CENTRAL, MEDLINE (1950-), EMBASE (1980-), CINAHL (1981-) and AMED (1985-), using relevant search terms and synonyms. The basic search strategy was ("droperidol" OR "butyrophenone") AND ("nausea" OR "vomiting"), modified for each database. We updated the search on 2 December 2009. We performed updated searches of MEDLINE, EMBASE, CENTRAL and AMED 2009 to 2013 on 19 November 2013 and of CINAHL on 20 November 2013. We also searched trial registers (metaRegister of controlled trials (www.controlled-trials.com/mrct), clinicaltrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (http://apps.who.int/trialsearch/)) on 22 November 2013, using the keyword "droperidol".

SELECTION CRITERIA

Randomised controlled trials (RCTs) of droperidol for the treatment of nausea or vomiting, or both, in adults receiving palliative care or suffering from an incurable progressive medical condition.

DATA COLLECTION AND ANALYSIS

We judged the potential relevance of studies based on their titles and abstracts, and obtained studies that we anticipated might meet the inclusion criteria. Two review authors independently reviewed the abstracts for the initial review and four review authors reviewed the abstracts for the update to assess suitability for inclusion. We discussed discrepancies to achieve consensus.

MAIN RESULTS

The 2010 search strategy identified 1664 abstracts (and 827 duplicates) of which we obtained 23 studies in full as potentially meeting the inclusion criteria. On review of the full papers, we identified no studies that met the inclusion criteria.The updated searches carried out in November 2013 identified 304 abstracts (261 excluding duplicates) of which we obtained 18 references in full as potentially meeting the inclusion criteria. On review of the full papers, we identified no studies that met the inclusion criteria, therefore there were no included studies in this review.We found no registered trials of droperidol for the management of nausea or vomiting in palliative care.

AUTHORS' CONCLUSIONS

Since first publication of this review, no new studies were found. There is insufficient evidence to advise on the use of droperidol for the management of nausea and vomiting in palliative care. Studies of antiemetics in palliative care settings are needed to identify which agents are most effective, with minimum side effects.

Changes in QTc interval in the citalopram for agitation in Alzheimer's disease (CitAD) randomized trial

Background

A Food and Drug Administration (FDA) safety communication in August 2011 warned that citalopram was associated with a dose dependent risk of QT prolongation and recommended dose restriction in patients over the age of 60 but did not provide data for this age group.

Methods

CitAD was a randomized, double-masked, placebo-controlled, multicenter clinical trial for agitation in Alzheimer's disease (AD). Participants were assigned to citalopram (target dose of 30 mg/day) or placebo in a 1∶1 ratio. 186 people, 181 of whom were over the age of 60, having probable AD with clinically significant agitation were recruited from September 2009 to January 2013. After the FDA safety communication about citalopram, ECG was added to the required study procedures before enrollment and repeated at week 3 to monitor change in QTc interval. Forty-eight participants were enrolled after enhanced monitoring began.

Results

Citalopram treatment was associated with a larger increase in QTc interval than placebo (difference in week 3 QTc adjusting for baseline QTc: 18.1 ms [95% CI: 6.1, 30.1]; p = 0.004). More participants in the citalopram group had an increase ≥30 ms from baseline to week 3 (7 in citalopram versus 1 in placebo; Fisher's exact p = 0.046), but only slightly more in the citalopram group met a gender-specific threshold for prolonged QTc (450 ms for males; 470 ms for females) at any point during follow-up (3 in citalopram versus 1 in placebo, Fisher's exact p = 0.611). One of the citalopram participants who developed prolonged QTc also displayed ventricular bigeminy. No participants in either group had a cardiovascular-related death.

Conclusion

Citalopram at 30 mg/day was associated with improvement in agitation in patients with AD but was also associated with QT prolongation.

Trial Registration

ClinicalTrials.gov NCT00898807

Perioperative doses of ondansetron or dolasetron do not lengthen the QT interval

OBJECTIVE

To test the primary hypothesis that ondansetron or dolasetron extends the rate-corrected QT electrocardiographic interval (QTc) greater than 60 milliseconds or increases the fraction of patients with QTc greater than 500 milliseconds in patients having noncardiac surgery, and the secondary hypothesis that QTc prolongation is worse in diabetic patients.

PATIENTS AND METHODS

We extracted data from the Cleveland Clinic's Perioperative Health Documentation System between March 25, 2006, and September 30, 2010, and additional perioperative medications from Cleveland Clinic pharmacy's Epic Cost of Goods Sold (COGS) system. We searched for patients who had a preoperative electrocardiogram within 1 month of surgery and postoperatively within 2 hours. We excluded patients given an antiemetic drug other than ondansetron or dolasetron perioperatively, and those given amiodarone.

RESULTS

A total of 1429 patients given serotonin-3 receptor (5HT3R) antagonists and 1022 controls met the enrollment criteria. Seventeen percent of patients given 5HT3R antagonists (n=242) and 22% of controls (n=220) had postoperative QTc exceeding 500 milliseconds. Mean ± SD presurgical and postsurgical QTc, respectively, were 438±37 milliseconds and 464±41 milliseconds for 5HT3R antagonist patients and 443±40 milliseconds and 469±47 milliseconds for control patients. Univariable mean ± SD perioperative increases in QTc were 26±39 and 26±48 milliseconds in the 2 groups. After adjusting for confounding variables, there were no differences in the mean increase in QTc in patients who were and were not given 5HT3R antagonists: -0.1 milliseconds (97.5% CI, -5.2 to 5.0 milliseconds; multivariable P=.97). The QTc was prolonged, but not significantly, in diabetic patients given 5HT3R antagonists (P=.16).

CONCLUSIONS

The average QTc prolongation from baseline was only 6%. Perioperative use of ondansetron or dolasetron was not associated with extended QT prolongation, and these results did not vary by diabetic status. Perioperative use of 5HT3R antagonists does not produce potentially dangerous perioperative electrocardiographic changes and does not seem to warrant a drug safety warning from the Food and Drug Administration.

Drugs to be avoided in patients with long QT syndrome: Focus on the anaesthesiological management

Long QT syndrome incidence is increasing in general population. A careful pre-, peri- and post-operative management is needed for patients with this syndrome because of the risk of Torsades de Pointes and malignant arrhythmias. The available data regarding prevention of lethal Torsades de Pointes during anesthesia in patients with long QT syndrome is scant and conflicting: only case reports and small case series with different outcomes have been published. Actually, there are no definitive guidelines on pre-, peri- and post-operative anesthetic management of congenital long QT syndrome. Our review focuses on anesthetic recommendations for patients diagnosed with congenital long QT syndrome furnishing some key points for preoperative optimization, intraoperative anesthetic agents and postoperative care plan, which could be the best for patients with c-long QT syndrome who undergo surgery.

Management of postoperative nausea and vomiting: how to deal with refractory PONV

Postoperative nausea and vomiting (PONV) constitutes a significant factor in delaying recovery after anesthesia and impairing patient satisfaction. To date the prevention of PONV using single or multimodal interventions, usually based on risk assessment, has gained some popularity. However, comprehensive implementation and knowledge transfer of the latest accomplishments in the prevention of PONV is only slowly being adopted into clinical practice. Preventing PONV is the first step in avoiding refractory PONV. This review comments mainly on the management of refractory PONV. As the data on coping with established PONV are rare, further studies focusing on treatment of established PONV are needed.

Different black box warning labeling for same-class drugs

INTRODUCTION

Black box warnings (BBWs) are the strongest medication-related safety warnings in a drug's labeling information and highlight major risks. Absence of a BBW or asynchronous addition of a BBW among same-class drugs could have major implications.

METHODS

We identified the 20 top-selling drugs in 2008 (10 with BBWs and 10 without BBWs on their label) that belonged to different drug classes. We collected labeling information on all drugs belonging in these 20 classes, and recorded differences in the presence and timing of acquisition of BBWs for same-class drugs.

RESULTS

Across the 20 evaluated drug classes, we identified 176 different agents, of which 7 had been withdrawn for safety reasons. The reasons for the withdrawals became BBWs in other same-class agents only in two of the seven cases. Differences were identified in 9 of the 20 classes corresponding to 15 BBWs that were not present in all drugs of the same class. The information for 10 of the 15 different BBWs were included in the labels of same-class drugs as simple warnings or text, while it was absent entirely in 5 BBWs. The median interval from the time the BBW had appeared in another drug of the same class was 66 months.

DISCUSSION

Differences in BBW labeling in same-class drugs are common and shape impressions about the safety of similar agents. BBW labeling needs to become more systematic.

[Postoperative nausea and vomiting and opioid-induced nausea and vomiting: guidelines for prevention and treatment]

Postoperative nausea and vomiting (PONV) causes patient discomfort, lowers patient satisfaction, and increases care requirements. Opioid-induced nausea and vomiting (OINV) may also occur if opioids are used to treat postoperative pain. These guidelines aim to provide recommendations for the prevention and treatment of both problems. A working group was established in accordance with the charter of the Sociedad Española de Anestesiología y Reanimación. The group undertook the critical appraisal of articles relevant to the management of PONV and OINV in adults and children early and late in the perioperative period. Discussions led to recommendations, summarized as follows: 1) Risk for PONV should be assessed in all patients undergoing surgery; 2 easy-to-use scales are useful for risk assessment: the Apfel scale for adults and the Eberhart scale for children. 2) Measures to reduce baseline risk should be used for adults at moderate or high risk and all children. 3) Pharmacologic prophylaxis with 1 drug is useful for patients at low risk (Apfel or Eberhart 1) who are to receive general anesthesia; patients with higher levels of risk should receive prophylaxis with 2 or more drugs and baseline risk should be reduced (multimodal approach). 4) Dexamethasone, droperidol, and ondansetron (or other setrons) have similar levels of efficacy; drug choice should be made based on individual patient factors. 5) The drug prescribed for treating PONV should preferably be different from the one used for prophylaxis; ondansetron is the most effective drug for treating PONV. 6) Risk for PONV should be assessed before discharge after outpatient surgery or on the ward for hospitalized patients; there is no evidence that late preventive strategies are effective. 7) The drug of choice for preventing OINV is droperidol.

Droperidol for treatment of nausea and vomiting in palliative care patients

BACKGROUND

Nausea and vomiting are common symptoms in patients with terminal illness and can be very unpleasant and distressing. There are several different types of antiemetic treatments which can be used to control these symptoms. Droperidol is an antipsychotic drug and has been used and studied as an antiemetic in the management of post-operative and chemotherapy nausea and vomiting.

OBJECTIVES

To evaluate the efficacy and adverse events (both minor and serious) associated with the use of droperidol for the treatment of nausea and vomiting in palliative care patients.

SEARCH STRATEGY

We searched electronic databases including CENTRAL, MEDLINE, EMBASE, CINAHL and AMED, using relevant search terms and synonyms. The basic search strategy was ("droperidol" OR "butyrophenone") AND ("nausea" OR "vomiting"), modified for each database. The search was updated on 2 December 2009.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of droperidol for the treatment of nausea or vomiting, or both, for adults receiving palliative care or suffering from an incurable progressive medical condition.

DATA COLLECTION AND ANALYSIS

We judged the potential relevance of studies based on their titles and abstracts, and obtained studies which we anticipated might meet the inclusion criteria. We both read these to assess suitability for inclusion. Discrepancies were discussed to achieve consensus.

MAIN RESULTS

The search strategy identified 1664 abstracts (and 827 duplicates) of which 23 studies were obtained in full as potentially meeting the inclusion criteria. On review of the full papers, no studies were identified which met the inclusion criteria, therefore, there were no included studies in this review.

AUTHORS' CONCLUSIONS

There is insufficient evidence to advise on the use of droperidol for the management of nausea and vomiting in palliative care. Studies of antiemetics in palliative care settings are needed to identify which agents are most effective with a minimum of side effects.

The effects of droperidol and ondansetron on dispersion of myocardial repolarization in children

OBJECTIVES

To compare the effects of droperidol and ondansetron on electrocardiographic indices of myocardial repolarization in children.

AIM

To refine understanding of the torsadogenic risk to children exposed to anti-emetic prophylaxis in the perioperative period.

BACKGROUND

QT interval prolongation is associated with torsades des pointes (TdP), but is a poor predictor of drug torsadogenicity. Susceptibility to TdP arises from increased transmural dispersion of repolarization (TDR) across the myocardial wall, rather than QT interval prolongation per se. TDR can be measured on the electrocardiogram as the time interval between the peak and end of the T wave (Tp-e). Tp-e may therefore provide a readily available, noninvasive assay of drug torsadogenicity. The perioperative period is one of high risk for TdP in children with or at risk of long QT syndromes. Droperidol and ondansetron are two drugs commonly administered perioperatively, for prophylaxis of nausea and vomiting, which can prolong the QT interval. This study investigated their effects on myocardial repolarization.

METHODS

One hundred and eight ASA1-2 children undergoing elective day-case surgery were randomized to receive droperidol, ondansetron, both or neither. Pre- and post-administration 12-lead electrocardiogram (ECGs) were recorded. QT and Tp-e intervals were measured and compared within and between groups, for the primary endpoint of a 25 ms change in Tp-e.

RESULTS

Eighty children completed the study. There were no demographic or baseline ECG differences between groups. QT intervals lengthened by 10-17 ms after allocated treatments, with no between-group differences. Values remained within normal limits for all groups. Tp-e intervals increased by 0-7 ms, with no between-group differences. There were no instances of dysrhythmia.

CONCLUSIONS

Droperidol and ondansetron, in therapeutic anti-emetic doses, produce equivalent, clinically insignificant QT prolongation and negligible Tp-e prolongation, suggesting that neither is torsadogenic in healthy children at these doses.

Inside the black box: current policies and concerns with the United States Food and Drug Administration's highest drug safety warning system

PURPOSE OF REVIEW

To evaluate the United States Food and Drug Administration use of the black-box warning system to promote drug safety and to examine the droperidol black-box warning as a case study.

RECENT FINDINGS

Scientific studies report that there is no basis to issue a black-box warning for perioperative administration of droperidol for postoperative nausea and vomiting on the basis of the potential of adverse cardiac events (prolongation of the QT interval and/or development of torsades de pointes).

SUMMARY

Rather than relying on well conducted clinical investigations, the Food and Drug Administration subjectively issued a black-box warning to droperidol, which effectively removed droperidol from clinical practice for the indication of postoperative nausea and vomiting. Newer data suggest that the incidence of prolongation of the QT interval and the occurrence of torsades de pointes is similar to more expensive alternative medications used to treat postoperative nausea and vomiting.

The subtype-specific effects of droperidol on action potential duration in cellular and computational models of long QT syndrome

BACKGROUND

Droperidol is a highly potent butyrophenone used for the therapy of postoperative nausea and vomiting. Its cardiac safety in cardiovascular-healthy patients and those with long QT (LQT) syndrome is a matter of debate. In this study, we investigated whether droperidol has subtype-specific effects in cellular and computational models of LQT syndrome.

METHODS

Left ventricular cardiac myocytes were isolated from adult guinea pig hearts. LQT1-like behavior was pharmacologically induced by chromanol 293B (10 micromol/L) and LQT2-like states by E4031 (10 micromol/L). Computational analysis was performed using the Luo-Rudy dynamic model. Data are given as mean + or - SEM.

RESULTS

In control myocytes, droperidol lengthened action potentials in a concentration-dependent manner with a maximal prolongation of 37% + or - 13% (n = 4) at a concentration of 0.6 micromol/L. In LQT1-like myocytes, droperidol (0.6 micromol/L) further prolonged action potentials by 31% + or - 6% (n = 6) but shortened action potentials of LQT2-like myocytes by 11% + or - 2% (n = 8). Computational modeling supported the concept that droperidol, in addition to the rapid component of the delayed K(+) current, blocks depolarizing targets, such as the L-type Ca(2+) current, the Na(+)-Ca(2+) exchanger, and the Na(+)-K(+) adenosine triphosphatase.

CONCLUSIONS

Droperidol has more detrimental effects on cardiac repolarization of LQT1-like than of LQT2-like myocytes suggesting subtype-specific cardiotoxic effects in patients with LQT syndrome. The subtype specificity of droperidol seems to be caused by a complex interaction of droperidol with several different molecular targets. This interaction deserves further investigation to establish the feasibility of a subtype-directed approach in the perioperative management of patients with LQT syndrome.

Droperidol use in pediatric emergency department patients

INTRODUCTION

Droperidol is a controversial drug with multiple clinical applications. This report examines the use of droperidol in pediatric emergency department (ED) patients.

METHODS

An observational structured chart review was conducted of patients 21 years or younger receiving droperidol as part of their ED treatment.

RESULTS

Over a 32-month period, 79 ED records were identified for review. Patients' ages ranged from 15 to 21 years with a mean age of 19.4 (T0.2) years. Indications for droperidol included agitation, 68 (86%); nausea/vomiting, 7 (9%); headache, 2 (3%); and other pain, 2 (3%). Droperidol was the initial therapy in 63 patients (80%) and the rescue medication in 16 (20%). In nonagitated patients, droperidol was 100% effective in controlling patient's symptoms, whereas in agitated patients, droperidol alone was 86.6% effective as a single agent. Within the agitated patients, 35 (51.5%) were positive for drugs, 15 (22.1%) were positive for drugs and alcohol, and 12 (17.6%) were positive for alcohol alone. All patients were placed on continuous cardiac monitoring immediately after administration of the drug and for the duration of their active ED visit. No cardiac arrhythmias were noted. Thirty-eight patients (48%) were discharged from the ED, 35 (44%) were transferred to the psychiatric crisis unit for evaluation, 5 (6%) were admitted, and in 1 patient with biliary colic, the disposition was not recorded. No admissions were for droperidol-associated complications.

CONCLUSIONS

Droperidol is a safe and effective medication in the adolescent and young adult population.

Thorough QT Studies: Questions and Quandaries

The International Conference on Harmonisation E14 Guidance was successful in largely standardizing the conduct of the so-called thorough QT/QTc studies (TQTS). Nevertheless, there is still a spectrum of frequently encountered problems with details of design, conduct and interpretation of TQTS. Several of these challenges are reviewed here, starting with explaining that the TQTS goal is only to identify drugs for which the proarrhythmic risk might be considered excluded for the purposes of regulatory benefit-risk assessment. Suggestions are made on how to categorize and quantify or exclude proarrhythmic risk if the TQTS is positive. There is a conceptual need for TQTS, and this is discussed, together with reasons why restricted clinical registries cannot prove the absence of proarrhythmic liability of any drug. Appropriate drug doses investigated in TQTS should be derived from the maximum clinically tolerable dose rather than from the known or expected therapeutic dose. With the help of concentration-QTc modelling, the standard therapeutic dose can be omitted from TQTS, especially if the study is expected to be negative. Conditions for single-dose TQTS acceptability are reviewed. The role of the so-called positive control is assessed, contrasting the role of a same-class comparator for the investigated drug. A single 400 mg dose of moxifloxacin is advocated as the present 'gold standard' assay sensitivity test. The necessity of careful placebo control is explained and the frequency of ECG assessments is considered. The central tendency and outlier analyses are discussed, together with the correct approaches to baseline adjustment. The review concludes that the design and interpretation of TQTS must not be approached with mechanistic stereotypes, and highlights the importance of relating the QTc changes to drug plasma levels.