Droperidol analgesia for opioid-tolerant patients

Droperidol Use in the Emergency Department: A Clinical Review

BACKGROUND

Droperidol is a butyrophenone, with antiemetic, sedative, anxiolytic, and analgesic properties. Although droperidol was once widely used in both emergency and perioperative settings, use of the medication declined rapidly after a 2001 U.S. Food and Drug Administration (FDA) boxed warning called the medication's safety into question.

OBJECTIVE

The purpose of this clinical review was to provide evidence-based answers to questions about droperidol's safety and to examine its efficacy in its various clinical indications.

DISCUSSION

Droperidol is an effective sedative, anxiolytic, analgesic, and antiemetic medication. As a sedative, when compared with haloperidol, droperidol has faster onset, as well as greater efficacy, in patients experiencing acute psychosis, with no increase in adverse events. As an antiemetic, droperidol has been found to have equal or greater efficacy in reducing nausea and vomiting than ondansetron and metoclopramide, with similar adverse effects and the added effect of reducing the need for rescue analgesia in these patients. As an analgesic, droperidol is effective for migraines and has opioid-sparing effects when used to treat abdominal pain. Droperidol is a particularly useful adjunct in patients who are opioid-tolerant, whose pain is often difficulty to manage adequately.

CONCLUSIONS

Droperidol seems to be effective and safe, despite the boxed warning issued by the FDA. Droperidol is a powerful antiemetic, sedative, anxiolytic, antimigraine, and adjuvant to opioid analgesia and does not require routine screening with electrocardiography when used in low doses in otherwise healthy patients before administration in the emergency department.

Predictive factors of postoperative fentanyl consumption in patients with inflammatory bowel disease: a retrospective cohort study

Background

Patients with inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis, might present difficulties in achieving postoperative analgesia. Prior studies have suggested that patients with IBD undergoing major abdominal surgery require higher doses of perioperative opioids than do patients without IBD. Considering patients with IBD potentially require high-dose opioids, identifying those requiring higher opioid doses will allow clinicians to optimize the perioperative opioid dose and avoid insufficient pain management or complications of opioid overdose. Therefore, we conducted this study to identify predictive factors that might influence postoperative opioid consumption in patients with IBD.

Methods

This single-center, historical cohort study reviewed the medical records of all patients admitted to the IBD center of our institution for surgery and who used intravenous fentanyl patient-controlled analgesia (PCA) after open abdominal surgery between June 2013 and April 2017. Ultimately, 179 patients were enrolled in the analysis. Variables expected to influence and/or represent pain, analgesia, inflammation, disease condition, and extent of surgery were selected as potential explanatory variables for predicting postoperative opioid consumption. Multivariable linear regression analysis was used to examine the effect of independent variables on postoperative fentanyl consumption.

Results

Of the nine predictive variables selected using the stepwise-selection method, eight were significant. Intraoperative fentanyl consumption, current smoking, ulcerative colitis, administration of biologics during the month before surgery, and the use of supplementary analgesics had a significant increasing effect on postoperative fentanyl consumption, whereas droperidol concentration in the PCA solution, age, and diabetes mellitus had a significant decreasing effect. Preoperative use of opioids was a non-significant variable. The adjusted coefficient of determination was 0.302.

Conclusions

Intraoperative fentanyl consumption, current smoking, ulcerative colitis, administration of biologics during the month before surgery, and the use of supplementary analgesics had a significant increasing effect, whereas droperidol concentration in the PCA solution, age, and diabetes mellitus had a significant decreasing effect on postoperative fentanyl consumption. These factors should be considered when adopting postoperative intravenous fentanyl PCA administration for patients with IBD.

Trial registration

Registry: UMIN Clinical Trials Registry.

Clinical Trial Number: UMIN000031198.

Date of registration: February 8, 2018.

Pain management in the emergency department: a clinical review

Pain is one of the most common reasons for patients to visit the emergency department. The ever-growing research on emergency department analgesia has challenged the current practices with respect to the optimal analgesic regimen for acute musculoskeletal pain, safe and judicious opioid prescribing, appropriate utilization of non-opioid therapeutics, and non-pharmacological treatment modalities. This clinical review is set to provide evidence-based answers to these challenging questions.

Low-dose Droperidol Reduces the Amplitude of Transcranial Electrical Motor-evoked Potential: A Randomized, Double-blind, Placebo-controlled Trial

BACKGROUND

Low-dose droperidol has been reported to suppress the amplitude of transcranial electrical motor-evoked potentials (TCE-MEPs), but no randomized controlled trials have been conducted to assess this. This randomized, double-blinded, placebo-controlled trial aimed to test the hypothesis that low-dose droperidol reduced TCE-MEP amplitudes.

METHODS

Twenty female patients with adolescent idiopathic scoliosis, aged between 12 and 20 years, and scheduled to undergo corrective surgery were randomly allocated to receive droperidol (20 µg/kg) or 0.9% saline. After recording baseline TCE-MEPs, the test drug was administered, following which TCE-MEP recordings were carried out every 2 minutes for up to 10 minutes. The primary outcome was the minimum relative TCE-MEP amplitude (peak-to-peak amplitude, percentage of baseline value) recorded in the left tibialis anterior muscle. Secondary outcomes included minimum relative MEP amplitudes recorded from all other muscle groups monitored in the study. Data are expressed as medians (interquartile range).

RESULTS

The TCE-MEP amplitude of the left tibialis anterior muscle was significantly reduced following droperidol administration compared with saline (37% [30% to 55%] vs. 76% [58% to 93%], respectively, P<0.01). In the other muscles, the amplitudes were reduced in the droperidol group, except for the bilateral abductor pollicis brevis and the left quadriceps femoris muscles. The relative amplitude of the bilateral F waves recorded from the gastrocnemius was decreased in the droperidol group.

CONCLUSIONS

Low-dose droperidol (20 µg/kg) reduced TCE-MEP amplitudes. Anesthesiologists should pay attention to the timing of droperidol administration during intraoperative TCE-MEP recordings, even if used in a low dose.

Reintegrating droperidol into emergency medicine practice

Purpose

After a long period of low utilization, droperidol has become easier to obtain in the US market. This comprehensive review discusses the safety, indications, clinical efficacy, and dosing of droperidol for use in the emergency department (ED) setting.

Summary

In 2001 the US Food and Drug Administration (FDA) mandated a boxed warning in the labeling of droperidol after reports of QT interval prolongation associated with droperidol use. Since that time, it has been difficult to access droperidol in the United States; as a result, many practicing clinicians lack experience in its clinical use. Multiple studies have been conducted to assess the clinical efficacy and safety of droperidol use in ED patients. Results consistently show the safety of droperidol and its clinical efficacy when used as an analgesic, antiemetic, and sedative. Now that droperidol is more widely available for use in the US market, pharmacists and prescribers need to reliably translate safety and efficacy data compiled since 2001 to help ensure appropriate and effective use of the medication.

Conclusion

Droperidol is an effective and safe option for the treatment of acute agitation, migraine, nausea, and pain for patients in the ED setting. Healthcare professionals can adopt droperidol for use in clinical practice, and they should become familiar with how to dose and monitor droperidol for safe and effective use.

Optimisation by Design of Experiment of Benzimidazol-2-One Synthesis under Flow Conditions

A novel flow-based approach for the preparation of benzimidazol-2-one (1) scaffold by the 1,1′-carbonyldiimidazole (CDI)-promoted cyclocarbonylation of o-phenylenediamine (2) is reported. Starting from a preliminary batch screening, the model reaction was successfully translated under flow conditions and optimised by means of design of experiment (DoE). The method allowed the efficient preparation of this privileged scaffold and to set up a general protocol for the multigram-scale preparation in high yield, purity, and productivity, and was successfully applied for the multigram flow synthesis of N-(2-chlorobenzyl)-5-cyano-benzimidazol-2-one, which is a key synthon for hit-to-lead explorations in our anti-inflammatory drug discovery program.

Rescue Sedation When Treating Acute Agitation in the Emergency Department With Intramuscular Antipsychotics

BACKGROUND

Rapid treatment of agitation in the emergency department (ED) is critical to avoid injury to patients and providers. Treatment with intramuscular antipsychotics is often utilized, but there is a paucity of comparative effectiveness evidence available.

OBJECTIVE

The purpose of this investigation was to compare the effectiveness of droperidol, olanzapine, and haloperidol for treating agitation in the ED.

METHODS

This was a retrospective observational study of adult patients who received intramuscular medication to treat agitation. Patients were classified based on the initial antipsychotic they received. The primary effectiveness outcome was the rate of additional sedation administered (rescue medication) within 1 h. Secondary outcomes included rescue sedation for the entire encounter and adverse events.

RESULTS

There were 15,918 patients included (median age 37 years, 75% male). Rescue rates at 1 h were: 547/4947 for droperidol (11%, 95% confidence interval [CI] 10-12%), 988/8825 olanzapine (11%, 95% CI 10-12%), and 390/2146 for haloperidol (18%, 95% CI 17-20%). Rescue rates for the entire ED encounter were: 832/4947 for droperidol (17%, 95% CI 16-18%), 1665/8825 for olanzapine (19%, 95% CI 18-20%), and 560/2146 for haloperidol (26%, 95% CI 24-28%). Adverse events were uncommon: intubation (49, 0.3%), akathisia (7, 0.04%), dystonia (5, 0.03%), respiratory arrest (1, 0.006%), and torsades de pointes (0), with no significant differences between drugs.

CONCLUSIONS

Olanzapine and droperidol lead to lower rates of rescue sedation at 1 h and overall, compared with haloperidol. There were no significant differences in major adverse events.

An open-label randomized trial of intramuscular olanzapine versus oral clonidine for symptomatic treatment of opioid withdrawal in the emergency department

Background: Patients with opioid withdrawal often present to the Emergency Department (ED), but many EDs do not have the infrastructure in place to initiate treatment with opioid agonists (methadone or buprenorphine). Therefore, ED management often entails symptomatic control. The purpose of this study was to compare olanzapine to clonidine for the treatment of opioid withdrawal symptoms. Methods: This was a prospective, randomized clinical trial comparing 10 mg of IM olanzapine to 0.3 mg of oral clonidine for symptoms of opioid withdrawal. Adult (18 years and older) ED patients reporting a history of opioid use and symptoms consistent with withdrawal were eligible. Patients were excluded if they had already received treatment during the ED encounter, were pregnant, incarcerated, or unable to provide consent. Patients were randomized 1:1 to receive olanzapine or clonidine for their initial treatment. A baseline Clinical Opiate Withdrawal Scale (COWS) score was calculated. After 30 min, the patient could receive any additional treatment at the ED physician's discretion. The primary outcome was need for additional medication (rescue) within 1 h of study medication administration. Secondary outcomes included change in COWS score and adverse reactions. Results: We enrolled 63 patients (33 olanzapine, 30 clonidine). Demographic characteristics were similar for both groups (median age 45, range 21-67, 54% male) as well as baseline COWS score (median score 11). The median time since last opiate use was 48 h for both groups (range 4-116). Rescue was given within 1 h for olanzapine for 9 (27%) patients and for clonidine in 19 (63%) patients (difference 36%, 95% CI 13-59%). Decrease in COWS score at 1 h was 8.3 for olanzapine and 5.1 for clonidine (difference 3.2, 95% CI 0.3-6). Adverse events were uncommon: akathisia (1, olanzapine), hypotension (2, clonidine), respiratory depression (0). Conclusions: Treatment of opioid withdrawal symptoms with 10 mg of IM olanzapine results in a lower incidence of rescue medication administration and improved symptoms (COWS score) compared to 0.3 mg of oral clonidine.

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.

Something for pain: Responsible opioid use in emergency medicine

The United States is currently experiencing a public health crisis of opioid addiction, which has its genesis in an industry marketing effort that successfully encouraged clinicians to prescribe opioids liberally, and asserted the safety of prescribing opioids for chronic non-cancer pain, despite a preponderance of evidence demonstrating the risks of dependence and misuse. The resulting rise in opioid use has pushed drug overdose deaths in front of motor vehicle collisions to become the leading cause of accidental death in the country. Emergency providers frequently treat patients for complications of opioid abuse, and also manage patients with acute and chronic pain, for which opioids are routinely prescribed. Emergency providers are therefore well positioned to both prevent new cases of opioid misuse and initiate appropriate treatment of existing opioid addicts. In opioid-naive patients, this is accomplished by a careful consideration of the likelihood of benefit and harm of an opioid prescription for acute pain. If opioids are prescribed, the chance of harm is reduced by matching the number of pills prescribed to the expected duration of pain and selecting an opioid preparation with low abuse liability. Patients who present to acute care with exacerbations of chronic pain or painful conditions associated with opioid misuse are best managed by treating symptoms with opioid alternatives and encouraging treatment for opioid addiction.

A Large Retrospective Cohort of Patients Receiving Intravenous Olanzapine in the Emergency Department

BACKGROUND

Olanzapine is an atypical antipsychotic with similar pharmacologic properties to droperidol. Due to the current droperidol shortage, the authors' clinical practice has been to substitute olanzapine for droperidol in many situations. At this time, olanzapine is U.S. Food and Drug Administration approved for oral and intramuscular (IM) use only, but due to its increased utility, intravenous (IV) olanzapine was recently approved for use in the study emergency department (ED).

OBJECTIVES

The authors sought to review the use and safety of IV olanzapine in the ED patient population.

METHODS

A retrospective review of consecutive patients receiving IV olanzapine between January 1, 2014, and July 1, 2014, was conducted. Data were collected via an electronic medical record review. The study was deemed exempt from informed consent by our institutional review board.

RESULTS

A total of 713 patients received IV olanzapine during the study period. The median age was 38 years (range = 18 to 85 years), and 313 patients were male (43.9%). Primary indications for IV olanzapine administration included acute agitation (n = 245, 34.4%), abdominal pain (n = 165, 23.1%), headache (n = 121, 17.0%), nausea and vomiting (n = 107, 15.0%), pain (other; n = 60, 8.4%), and unknown (n = 15, 2.1%). IV dosing varied: 1.25 mg (n = 20, 2.8%), 2.5 mg (n = 185, 25.9%), 5 mg (n = 507, 71.1%), and 10 mg (n = 1, 0.1%). Forty-nine patients required a second dose of olanzapine (22 IV, 26 IM, one oral). The maximum total dose of olanzapine was 20 mg. Ninety-eight patients required a total of 146 doses of additional sedatives during their ED course. Other sedative medications included ketamine (n = 17, 2.4%), haloperidol (n = 48, 6.7%), and benzodiazepines (n = 81, 11.4%). Hypoxia was noted in 74 patients (10.4%). Major respiratory complications, including airway stimulation or repositioning maneuvers and intubation, occurred in 15 patients (2.1%). After consensus review, one intubation was classified as "likely related" to olanzapine administration, and two were classified as "possibly related" to olanzapine. Akathisia likely occurred in four patients (0.6%), and no allergic reactions were identified. Electrocardiograms (ECGs) were performed in 322 patients. A total of 251 patients had an ECG performed before olanzapine administration (median QTc = 404 ms), and 88 patients had an ECG performed after olanzapine administration (median QTc = 415 ms). Acute alcohol and drug intoxication was common, 118 (16.5%) patients were positive for ethanol, and seven of 23 drug screens were positive for sympathomimetics. Thirty-four of 284 admissions (4.5%) were to intermediate or intensive care unit beds. No patients died while in the ED and no cases of sudden cardiac death were noted.

CONCLUSIONS

In this large retrospective review, IV olanzapine appears to be a safe in the management of a variety of ED indications. Hypoxia was common, but serious airway compromise was rare.

Elucidation of in vitro phase I metabolites of droperidol using UPLC-QTOF MS

Droperidol, an antidopaminergic drug clinically used as an antiemetic and antipsychotic, has been reported to induce cardiac toxicity in patients. Due to the close relationship between drug metabolism and efficiency and toxicity, the present study aims to investigate the phase I metabolites using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. The NADPH-supplemented phase I incubation system was used to elucidate the in vitro phase I metabolites. Five metabolites were detected after droperidol was incubated with phase I incubation mixture, including one hydrogenated droperidol, three oxidative metabolites, and one N-dealkylated droperidol, elucidated by individual retention time and MS/MS fragmentation. Due to the existed phase II metabolic reaction, further phase II metabolism should be investigated in the future. In conclusion, the phase I metabolism of droperidol was investigated in the present study, and five new metabolites were identified. The efficiency and toxicity of these phase I metabolites should be investigated in the future.

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.

Capturing the aversive state of cephalic pain preclinically

OBJECTIVE

Preclinical evaluation of headache by behavioral assessment of reward from pain relief.

METHODS

Inflammatory mediators (IMs) or control solution were applied to the rat dura mater to elicit a presumed state of cephalic pain. Hind paw incision was used in separate groups of animals to model noncephalic postsurgical pain. Drugs were given systemically or microinjected within the rostral ventromedial medulla (RVM), nucleus accumbens (NAc), or rostral anterior cingulate cortex (rACC). Peripheral nerve block was produced at the level of the popliteal fossa, and behavior was assessed using evoked sensory stimuli or conditioned place preference (CPP). Immunohistochemistry and brain microdialysis measurements were performed.

RESULTS

Dural IMs produced long-lasting generalized cutaneous allodynia. RVM lidocaine produced CPP, increased NAc c-Fos, and dopamine release selectively in rats receiving dural IMs; CPP was blocked by intra-NAc α-flupenthixol, a dopaminergic antagonist. Intravenous α-calcitonin gene-related peptide (αCGRP)(8-37) produced CPP and elicited NAc dopamine release selectively in rats treated with dural IMs. Prior lesion of the rACC or treatment with systemic sumatriptan or αCGRP(8-37) abolished RVM lidocaine-induced CPP in IM-treated rats. Sumatriptan treatment blocked NAc dopamine release in IM-treated rats receiving RVM lidocaine. Systemic sumatriptan did not alter pain relief-induced CPP in rats with incisional injury.

INTERPRETATION

Cephalic pain was unmasked in rats by assessment of motivated behavior to seek relief. Relief of pain activates the dopaminergic reward pathway to elicit negative reinforcement of behavior. Medications clinically effective for migraine headache selectively elicit relief of ongoing cephalic, but not postsurgical, noncephalic pain. These studies provide a platform for exploring migraine pathophysiology and for the discovery of new headache therapies.

Recent Publications on Medications and Pharmacy

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