Differential changes in QTc duration during in-hospital haloperidol use

The safety and efficacy of sequential intramuscular/oral ziprasidone treatment of acute episode in patients with schizophrenia: a multicenter, open-labeled study

BACKGROUND

Ziprasidone mesylate injection is an atypical antipsychotic drug which is recently approved in China. In combination with its oral formulation, sequential therapy with ziprasidone brings new interventions to patients with agitation in the acute phase of schizophrenia. The purpose of this 7-day multicenter study conducted in China was to evaluate the efficacy and safety of ziprasidone sequential treatment through intramuscular/oral routes in agitated patients with schizophrenia.

METHODS

A total of 95 patients were enrolled from three centers in this study. The study duration was 7 days. In the first 3 days, subjects were administered an intramuscular injection of ziprasidone 10-40 mg daily and started sequentially with oral ziprasidone 40-80 mg at dinner (or lunch) from the day of the last intramuscular injection. In the following 4 days, according to the severity of the symptoms and the drug response, 120-160 mg of ziprasidone was orally administered daily. In total, six visits were scheduled to assess the Positive and Negative Syndrome Scale (PANSS), the Behavioral Activity Rating Scale (BARS), the Clinical Global Impression of Severity (CGI-S), and Improvement (CGI-I) scores throughout the procedure. Lastly, adverse events were recorded during treatment.

RESULTS

Out of the 95 patients that were enrolled, 83 cases were effectively completed. Visits 3, 4, 6, PANSS, and PANSS-excited component (PANSS-EC) subscale points, and Visit 2-Visit 6 viewpoints, BARS scale points, and baseline scores denote a progressive downward trend (P < 0.001). In this study, 62 adverse events were reported. The most common adverse events were extrapyramidal symptoms (EPS) (23 cases) and excessive sedation(10 cases), and 13 cases of prolonged QTc interval were reported.

CONCLUSIONS

Ziprasidone IM demonstrated significant and rapid reduction in agitation, and sequential oral formulation keep stability and continuation of the treatment can further ensure efficacy. Ziprasidone sequential therapy may provide a new approach to acute agitation in schizophrenic patients.

TRIAL REGISTRATION

The Chinese Clinical Trials Registry; URL: https://www.chictr.org.cn : ChiCTR-OIC-16007970.

Genetic Biomarkers of Antipsychotic-Induced Prolongation of the QT Interval in Patients with Schizophrenia

Antipsychotics (AP) induced prolongation of the QT interval in patients with schizophrenia (Sch) is an actual interdisciplinary problem as it increases the risk of sudden death syndrome. Long QT syndrome (LQTS) as a cardiac adverse drug reaction is a multifactorial symptomatic disorder, the development of which is influenced by modifying factors (APs' dose, duration of APs therapy, APs polytherapy, and monotherapy, etc.) and non-modifying factors (genetic predisposition, gender, age, etc.). The genetic predisposition to AP-induced LQTS may be due to several causes, including causal mutations in the genes responsible for monoheme forms of LQTS, single nucleotide variants (SNVs) of the candidate genes encoding voltage-dependent ion channels expressed both in the brain and in the heart, and SNVs of candidate genes encoding key enzymes of APs metabolism. This narrative review summarizes the results of genetic studies on AP-induced LQTS and proposes a new personalized approach to assessing the risk of its development (low, moderate, high). We recommend implementation in protocols of primary diagnosis of AP-induced LQTS and medication dispensary additional observations of the risk category of patients receiving APs, deoxyribonucleic acid profiling, regular electrocardiogram monitoring, and regular therapeutic drug monitoring of the blood APs levels.

Dynamics of the QTc interval over a 24-h dose interval after start of intravenous ciprofloxacin or low-dose erythromycin administration in ICU patients

QTc interval prolongation is an adverse effect associated with the use of fluoroquinolones and macrolides. Ciprofloxacin and erythromycin are both frequently prescribed QTc-prolonging drugs in critically ill patients. Critically ill patients may be more vulnerable to developing QTc prolongation, as several risk factors can be present at the same time. Therefore, it is important to know the QTc-prolonging potential of these drugs in the intensive care unit (ICU) population. The aim of this study was to assess the dynamics of the QTc interval over a 24-hour dose interval during intravenous ciprofloxacin and low-dose erythromycin treatment. Therefore, an observational study was performed in ICU patients (≥18 years) receiving ciprofloxacin 400 mg t.i.d. or erythromycin 100 mg b.i.d. intravenously. Continuous ECG data were collected from 2 h before to 24 h after the first administration. QT-analyses were performed using high-end holter software. The effect was determined with a two-sample t-test for clustered data on all QTc values. A linear mixed model by maximum likelihood was applied, for which QTc values were assessed for the available time intervals and therapy. No evident effect over time on therapy with ciprofloxacin and erythromycin was observed on QTc time. There was no significant difference (p = 0.22) in QTc values between the ciprofloxacin group (mean 393 ms) and ciprofloxacin control group (mean 386 ms). The erythromycin group (mean 405 ms) and erythromycin control group (mean 404 ms) neither showed a significant difference (p = 0.80). In 0.6% of the registrations (1.138 out of 198.270 samples) the duration of the QTc interval was longer than 500 ms. The index groups showed slightly more recorded QTc intervals over 500 ms. To conclude, this study could not identify differences in the QTc interval between the treatments analyzed.

The use of a clinical decision support tool to assess the risk of QT drug-drug interactions in community pharmacies

Introduction:

The handling of drug–drug interactions regarding QTc-prolongation (QT-DDIs) is not well defined. A clinical decision support (CDS) tool will support risk management of QT-DDIs. Therefore, we studied the effect of a CDS tool on the proportion of QT-DDIs for which an intervention was considered by pharmacists.

Methods:

An intervention study was performed using a pre- and post-design in 20 community pharmacies in The Netherlands. All QT-DDIs that occurred during a before- and after-period of three months were included. The impact of the use of a CDS tool to support the handling of QT-DDIs was studied. For each QT-DDI, handling of the QT-DDI and patient characteristics were extracted from the pharmacy information system. Primary outcome was the proportion of QT-DDIs with an intervention. Secondary outcomes were the type of interventions and the time associated with handling QT-DDIs. Logistic regression analysis was used to analyse the primary outcome.

Results:

Two hundred and forty-four QT-DDIs pre-CDS tool and 157 QT-DDIs post-CDS tool were included. Pharmacists intervened in 43.0% and 35.7% of the QT-DDIs pre- and post-CDS tool respectively (odds ratio 0.74; 95% confidence interval 0.49–1.11). Substitution of interacting agents was the most frequent intervention. Pharmacists spent 20.8 ± 3.5 min (mean ± SD) on handling QT-DDIs pre-CDS tool, which was reduced to 14.9 ± 2.4 min (mean ± SD) post-CDS tool. Of these, 4.5 ± 0.7 min (mean ± SD) were spent on the CDS tool.

Conclusion:

The CDS tool might be a first step to developing a tool to manage QT-DDIs via a structured approach. Improvement of the tool is needed in order to increase its diagnostic value and reduce redundant QT-DDI alerts.

Plain Language Summary

The use of a tool to support the handling of QTc-prolonging drug interactions in community pharmacies

Introduction: Several drugs have the ability to cause heart rhythm disturbances as a rare side effect. This rhythm disturbance is called QTc-interval prolongation. It may result in cardiac arrest. For health care professionals, such as physicians and pharmacists, it is difficult to decide whether or not it is safe to proceed treating a patient with combinations of two or more of these QT-prolonging drugs. Recently, a tool was developed that supports the risk management of these QT drug–drug interactions (QT-DDIs).

Methods: In this study, we studied the effect of this tool on the proportion of QT-DDIs for which an intervention was considered by pharmacists. An intervention study was performed using a pre- and post-design in 20 community pharmacies in The Netherlands. All QT-DDIs that occurred during a before- and after-period of 3 months were included.

Results: Two hundred and forty-four QT-DDIs pre-implementation of the tool and 157 QT-DDIs post-implementation of the tool were included. Pharmacists intervened in 43.0% of the QT-DDIs before the tool was implemented and in 35.7% after implementation of the tool. Substitution of one of the interacting agents was the most frequent intervention. Pharmacists spent less time on handling QT-DDIs when the tool was used.

Conclusion: The clinical decision support tool might be a first step to developing a tool to manage QT-DDIs via a structured approach.

QTc Prolongation in COVID-19 Patients Using Chloroquine

Chloroquine is used in the treatment of patients with COVID-19 infection, although there is no substantial evidence for a beneficial effect. Chloroquine is known to prolong the QRS and QTc interval on the ECG. To assess the effect of chloroquine on QRS and QTc intervals in COVID-19 patients, we included all inpatients treated with chloroquine for COVID-19 in the Spaarne Gasthuis (Haarlem/Hoofddorp, the Netherlands) and had an ECG performed both in the 72 h before and during or at least 48 h after treatment. We analyzed the (change in) QRS and QTc interval using the one-sample t-test. Of the 106 patients treated with chloroquine, 70 met the inclusion criteria. The average change in QRS interval was 6.0 ms (95% CI 3.3–8.7) and the average change in QTc interval was 32.6 ms (95% CI 24.9–40.2) corrected with the Bazett’s formula and 38.1 ms (95% CI 30.4–45.9) corrected with the Fridericia’s formula. In 19 of the 70 patients (27%), the QTc interval was above 500 ms after start of chloroquine treatment or the change in QTc interval was more than 60 ms. A heart rate above 90 bpm, renal dysfunction, and a QTc interval below 450 ms were risk factors for QTc interval prolongation. Chloroquine prolongs the QTc interval in a substantial number of patients, potentially causing rhythm disturbances. Since there is no substantial evidence for a beneficial effect of chloroquine, these results discourage its use in COVID-19 patients.

Should we still monitor QTc duration in frail older patients on low-dose haloperidol? A prospective observational cohort study

BACKGROUND

Haloperidol at high dosage is associated with QTc prolongation and polymorphic ventricular arrhythmia but the effects of low-dose haloperidol remain unknown.

OBJECTIVE

To evaluate the effects of low-dose haloperidol on QTc-duration in frail hospitalized elderly patients with delirium.

METHODS

A prospective observational study including hospitalized patients aged ≥70 years with Groningen Frailty Index-score > 3. We included 150 patients who received haloperidol and 150 age- and frailty-matched control patients. Serial ECG recordings were performed at hospital admission and during hospitalization. QT-interval was corrected according to Framingham (QTc). Patients were grouped according to baseline QTc in normal (nQTc), borderline (bQTc) or abnormal (aQTc). Primary outcome was change in QTc-duration between first and second ECG. Potentially dangerous QTc was defined as QTc >500 ms or an increase of >50 ms.

RESULTS

Patients in the haloperidol group (48% male, mean age 85y, nQT n = 98, bQT n = 31, aQT n = 20) received an average dose of 1.5 mg haloperidol per 24 hours. QTc decreased in patients with borderline (mean - 15 ± 29 ms, P < 0.05) or abnormal (-19 ± 27 ms, P < 0.05) QTc at baseline, no patients developed dangerous QTc-duration. In the control group (41% male, mean age 84y, nQT n = 99 bQT n = 29, aQT n = 22) QTc decreased to a similar extent (bQT -7 ± 16 ms, aQTc -23 ± 20 ms).

CONCLUSION

A trend to QTc shortening was seen, especially in patients with borderline or abnormal QTc at baseline, regardless of haloperidol use. These findings suggest that ECG monitoring of frail elderly patients who receive low-dose haloperidol, may not be necessary.

Prevalence of QTc Prolongation in Patients With Advanced Cancer Receiving Palliative Care-A Cause for Concern?

CONTEXT

Medications commonly used for symptom control along with other known risk factors have the potential to prolong ventricular repolarization as measured by the QT interval (the time from the start of the Q wave to the end of the T wave) on a standard electrocardiogram (ECG).

OBJECTIVES

To document the prevalence of a prolonged QT interval corrected for heart rate (QTc) interval in the palliative/oncology setting, compare automatic ECG QTc measurements with manual readings and identify any correlation between QTc prolongation and the use of drugs or other risk factors.

METHODS

A convenience sample of consecutive patients with cancer, admitted under or known to the palliative/supportive care teams in two metropolitan hospitals, and willing to provide an ECG recording and basic demographic information including QTc risk factors were included. Both automated and manually calculated QTc intervals were recorded. Multivariable analysis was used to determine risk factors independently associated with prolonged QTc intervals.

RESULTS

Of the 389 participants, there was a significant difference in mean QTc between sites using automated but not manual calculations. Manual readings were therefore used with predetermined cutoffs of 0.44 seconds (males) and 0.46 seconds (females). Seventy-two (18.5%) of the participants had a prolonged QTc with six (1.5%) having a prolongation of >0.50 seconds. At-risk drugs were being taken by 218 participants (56.0% of total cohort). Factors shown to be associated with QTc prolongation included age, gender, performance status, and hypocalcemia. No specific medication was associated with increased risk.

CONCLUSION

Although almost 20% of patients receiving palliative care had prolongation of QTc, the possibility of serious consequences appeared to be low despite the frequent occurrence of risk factors.

A prolonged QTc-interval at the emergency department: Should we always be prepared for the worst?

INTRODUCTION

QTc-interval prolongation is associated with ventricular arrhythmias and mortality in a general population. Bazett's correction formula (QTcB) is routinely used despite its overcorrection at high heart rates. Recently, we proposed a patient-specific QT correcting algorithm (QTcA) resulting in improved rate correction and predictive value in a general population. We hypothesize risk stratification at the Emergency Department (ED) could be improved using QTcA.

METHODS AND RESULTS

A retrospective case-control study including a randomized age- and sex-matched control population was performed at a tertiary care ED. A total of 1930 patients were included in the analysis (63.0% males, age 71.5 ± 15.6 years). Patient characteristics, history, and test results at the time of the electrocardiogram were collected. QTc was dichotomized as prolonged (>450 millisecond for men, >470 millisecond for women) or severely prolonged (>500 millisecond). Implementation of QTcA would reduce the number of patients considered to have a prolonged QTc by 65.2%, for severely prolonged QTc 79.6%. Multivariate regression was performed for in-hospital mortality, cardiovascular endpoints, and hospital admission. Neither a prolonged QTcB (HR 1.04; 95% CI, 0.64-1.69) nor QTcA (HR 0.76; 95% CI, 0.42-1.38) was an independent predictor of in-hospital mortality. A severely prolonged QTcA (OR, 2.54; 95% CI, 1.04-6.23) was an independent predictor of cardiovascular events. Both a prolonged QTcA (OR, 1.52; 95% CI, 1.06-2.18) and a prolonged QTcB (OR, 1.37; 95% CI, 1.05-1.79) were associated with higher hospitalization rates.

CONCLUSIONS

QTcA reduced the number of patients considered at risk. Neither QTcB nor QTcA were predictors of in-hospital mortality. A severely prolonged QTcA was associated with cardiovascular events.

Low dose oral haloperidol does not prolong QTc interval in older acutely hospitalised adults: a subanalysis of a randomised double-blind placebo-controlled study

BACKGROUND

Haloperidol is the most frequently prescribed antipsychotic for delirium symptoms. The risk of QTc prolongation often raises concerns, although the effect of haloperidol on QTc interval has not yet been investigated in a randomised placebo-controlled fixed-dose study.

METHODS

A subanalysis of a randomised double-blind placebo-controlled study was conducted to evaluate the effect of prophylactic haloperidol 1 mg or placebo 1 mg orally twice-daily (maximum of 14 doses) on QTc interval in patients aged 70 years and over. Bedside, 12-lead ECGs were recorded before, during and after the one-week intervention period. Automatic QTc measurements were obtained in addition to manual measurements of QT and RR intervals, blinded for treatment status. Manual measurements were corrected (QTc) using Bazett (QTc-B), Framingham (QTc-Fa), Fridericia (QTc-Fi) and Hodges (QTc-H) methods. Mixed model analyses were used to test for differences in longitudinal course of QTc between patients receiving haloperidol and placebo.

RESULTS

ECG recordings of 72 patients (haloperidol n = 38) were analysed, 45.8% male. Median (range) haloperidol serum concentration on day 4 was 0.71 (0.32-1.82) µg/L (n = 23). Longitudinal course of mean QTc did not significantly differ between treatment arms for any of the automatic or manually derived QTc values.

CONCLUSIONS

Low dose oral haloperidol did not result in QTc prolongation in older acutely hospitalised patients. Results may not be generalizable to patients with existing ECG abnormalities such as atrial fibrillation.

Risk Management of Hospitalized Psychiatric Patients Taking Multiple QTc-Prolonging Drugs

PURPOSE/BACKGROUND

Drug-related QTc prolongation has been linked with Torsade de Pointes and sudden cardiac death. The objective of this study was to investigate the impact of starting an additional QTc-prolonging drug on the QTc interval of psychiatric inpatients.

METHODS

An observational study was performed between May 2011 and December 2014 in 6 Belgian psychiatric hospitals. Inpatients who were already taking 1 QTc-prolonging drug or more could be included in the study when an additional QTc-prolonging drug was started. Electrocardiograms were performed at baseline and follow-up. Demographic, medical, medication, and laboratory data were collected. A risk score was used to estimate the risk of QTc prolongation based on patient-specific risk factors. A cutoff value of 8 points was set as high risk for QTc prolongation.

RESULTS

One hundred fifty-two patients (44.7% women; mean age, 44 [SD, 17] years) were included who received a prescription for an additional QTc-prolonging drug. There was a small but significant difference (P = 0.032) in mean QTc interval between baseline (409.1 [SD, 21.8] milliseconds) and follow-up (411.8 [SD, 21.7] milliseconds). Three patients developed a prolonged QTc interval in the follow-up electrocardiogram (QTc, ≥450 [men]/470 [women] milliseconds); 8 patients had a delta QTc of 30 milliseconds or longer. No cases of torsade de pointes or sudden cardiac death were identified. Fifty-eight patients (38.2%) had a risk score of 8 or higher; these patients had a significantly longer QTc interval at follow-up than did patients with a risk score of lower than 8 (P < 0.001).

IMPLICATIONS/CONCLUSIONS

Only a limited number of patients developed a prolonged QTc interval after the start of an additional QTc-prolonging drug. Nevertheless, it is still important to screen for high-risk patients at baseline. A risk score can help to select high-risk patients and to stimulate an appropriate and feasible risk management of QTc prolongation in psychiatry.

Haloperidol Versus 5-HT3 Receptor Antagonists for Postoperative Vomiting and QTc Prolongation: A Noninferiority Meta-Analysis and Trial Sequential Analysis of Randomized Controlled Trials

Haloperidol is an antipsychotic with well-known antiemetic potential. It is underutilized for postoperative nausea vomiting due to reported corrected QT interval (QTc) prolongation. This meta-analysis evaluates its safety and efficacy as an antiemetic in the perioperative period. Trials comparing haloperidol to 5-HT₃ -receptor antagonists (5-HT₃ -RA) for 24 postoperative vomiting incidences published up to May 2017 were searched in the medical database. Comparisons were made for antiemetic efficiency variables (vomiting incidence, rescue antiemetic need, and patients with complete response) during early (until 6 hours) and late postoperative phases. Eight randomized controlled double-blinded trials were included in the final analysis. Twenty-four-hour vomiting incidence was similar in groups (fixed effects, P = 0.52, I² = 0%). Trial-sequential analysis confirmed noninferiority of haloperidol over 5-HT₃ -RAs (α = 5%, β = 20%, δ = 10%), with "information size" being 859 (required > 812). Pooled results did not demonstrate superiority/inferiority of 5-HT₃ -RAs over haloperidol in all other antiemetic efficacy variables (early and delayed). Negligible heterogeneity was found in all the comparisons made. Pooled Mantel Haenszel odds ratio for QTc prolongation was equivalent in both groups (fixed effects, P = 0.23, I² = 0%). The mean dose of haloperidol used was 1.34 mg, and no trial reported extrapyramidal side effects. Trial-sequential analysis showed statistical equivalence (α = 5%, β = 20%, δ = 10%), with information size being 745 (required > 591). Publication bias was unlikely (Egger test, X-intercept = 2.07, P = 0.10). We conclude that haloperidol is equivalent to the well-established 5-HT₃ -RAs in preventing vomiting during the first day after surgery. The incidence of QTc prolongation with haloperidol is statistically equivalent to 5-HT₃ -RAs and thus should not be the factor that discourages its use for treatment/prophylaxis of postoperative nausea vomiting.

QTc interval lengthening in first-episode schizophrenia (FES) patients in the earliest stages of antipsychotic treatment

Antipsychotic use is reported to be associated with a higher risk of sudden cardiac death and new users are especially susceptible to that risk. In this study, we focused on the ability of antipsychotics to prolong the QTc interval at the earliest stages of antipsychotic use. We employed a retrospective cohort study design in a naturalistic setting where having three ECG measurements over time (at baseline and after drug exposure) in antipsychotic-naïve, first-episode schizophrenia (FES) inpatients. The results revealed, in this relatively homogeneous, drug naïve FES patient sample, that QTc intervals were statistically significantly prolongated after a relatively short term (2-4weeks) of antipsychotic treatments, compared with baseline. After about 2 or 4weeks of antipsychotic use, the risk of abnormal QTc prolongation was higher than at baseline. These results reinforce the importance of monitoring risk factors and assessing QTc prolongation at the beginning and throughout treatment with antipsychotics.

In-Hospital Haloperidol Use and Perioperative Changes in QTc-Duration

OBJECTIVES

Haloperidol may prolong ECG QTc-duration but is often prescribed perioperatively to hip-fracture patients. We aimed to determine (1) how QTc-duration changes perioperatively, (2) whether low-dose haloperidol-use influences these changes, and (3) which clinical variables are associated with potentially dangerous perioperative QTc-prolongation (PD-QTc; increase >50 ms or to >500 ms).

DESIGN

Prospective cohort study.

SETTING

Tertiary university teaching-hospital.

PARTICIPANTS

Patients enrolled in a randomized controlled clinical trial of melatonin versus placebo on occurrence of delirium in hip-fracture patients.

MEASUREMENTS

Data from ECGs made before and after hip surgery (1-3 days and/or 4-6 days post-surgery) were analyzed. QTc-duration was measured by hand, blinded for haloperidol and pre/post-surgery status. Clinical variables were measured at baseline. Mixed model analysis was used to estimate changes in QTc-duration. Risk-factors for PD-QTc were estimated by logistic regression analysis.

RESULTS

We included 89 patients (mean age 84 years, 24% male); 39 were treated with haloperidol. Patients with normal pre-surgery QTc-duration (male ≤430 ms, female ≤450 ms) had a significant increase (mean 12 ms, SD 28) in QTc-duration. A significant decrease (mean 19 ms, SD 34) occurred in patients with prolonged pre-surgery QTc-duration (male >450ms, female >470 ms). Haloperidol-use did not influence the perioperative course of the QTc-interval (p=0.351). PD-QTc (n=8) was not associated with any of the measured risk-factors.

CONCLUSION

QTc-duration changed differentially, increasing in patients with normal, but decreasing in patients with abnormal baseline QTc-duration. PD-QTc was not associated with haloperidol-use or other risk-factors. Low-dose oral haloperidol did not affect perioperative QTc-interval.

Treating an established episode of delirium in palliative care: expert opinion and review of the current evidence base with recommendations for future development

CONTEXT

Delirium is a highly prevalent complication in patients in palliative care settings, especially in the end-of-life context.

OBJECTIVES

To review the current evidence base for treating episodes of delirium in palliative care settings and propose a framework for future development.

METHODS

We combined multidisciplinary input from delirium researchers and other purposely selected stakeholders at an international delirium study planning meeting. This was supplemented by a literature search of multiple databases and relevant reference lists to identify studies regarding therapeutic interventions for delirium.

RESULTS

The context of delirium management in palliative care is highly variable. The standard management of a delirium episode includes the investigation of precipitating and aggravating factors followed by symptomatic treatment with drug therapy. However, the intensity of this management depends on illness trajectory and goals of care in addition to the local availability of both investigative modalities and therapeutic interventions. Pharmacologically, haloperidol remains the practice standard by consensus for symptomatic control. Dosing schedules are derived from expert opinion and various clinical practice guidelines as evidence-based data from palliative care settings are limited. The commonly used pharmacologic interventions for delirium in this population warrant evaluation in clinical trials to examine dosing and titration regimens, different routes of administration, and safety and efficacy compared with placebo.

CONCLUSION

Delirium treatment is multidimensional and includes the identification of precipitating and aggravating factors. For symptomatic management, haloperidol remains the practice standard. Further high-quality collaborative research investigating the appropriate treatment of this complex syndrome is needed.

Emerging drugs of abuse: current perspectives on substituted cathinones

Substituted cathinones are synthetic analogs of cathinone that can be considered as derivatives of phenethylamines with a beta-keto group on the side chain. They appeared in the recreational drug market in the mid-2000s and now represent a large class of new popular drugs of abuse. Initially considered as legal highs, their legal status is variable by country and is rapidly changing, with government institutions encouraging their control. Some cathinones (such as diethylpropion or pyrovalerone) have been used in a medical setting and bupropion is actually indicated for smoking cessation. Substituted cathinones are widely available from internet websites, retail shops, and street dealers. They can be sold under chemical, evocative or generic names, making their identification difficult. Fortunately, analytical methods have been developed in recent years to solve this problem. Available as powders, substituted cathinones are self-administered by snorting, oral injestion, or intravenous injection. They act as central nervous system stimulants by causing the release of catecholamines (dopamine, noradrenaline, and serotonin) and blocking their reuptake in the central and peripheral nervous system. They may also decrease dopamine and serotonin transporter function as nonselective substrates or potent blockers and may inhibit monoamine oxidase effects. Nevertheless, considerable differences have been found in the potencies of the different substituted cathinones in vitro. Desired effects reported by users include increased energy, empathy, and improved libido. Cardiovascular (tachycardia, hypertension) and psychiatric/neurological signs/symptoms (agitation, seizures, paranoia, and hallucinations) are the most common adverse effects reported. Severe toxicity signs compatible with excessive serotonin activity, such as hyperthermia, metabolic acidosis, and prolonged rhabdomyolysis, have also been observed. Reinforcing potential observed in animals predicts a high potential for addiction and abuse in users. In case of overdose, no specific antidote exists and no curative treatment has been approved by health authorities. Therefore, management of acute toxic effects is mainly extrapolated from experience with cocaine/amphetamines.

The assessment and management of the violent patient in critical hospital settings

OBJECTIVE

Patient violence and aggression is prevalent in critical care settings, yet clinicians are often inadequately trained to assess and respond to these types of behaviors. Targeted toward trainees as well as seasoned clinicians, this articles provides an updated review of the literature regarding the management of violence in the emergency department.

METHODS

This narrative review is largely derived from research articles and reviews published since 2000. We conducted a systematic search of electronic databases for review articles or studies examining patient violence and aggression in critical care settings. Electronic searches were supplemented by manual searches of reference lists.

RESULTS

Current statistics, risk factors and imminent signs of violent patient behavior are presented. We conclude with recommendations for pharmacological and psychological interventions that can help manage aggressive behavior in the emergency department.

CONCLUSIONS

The relatively high frequency of aggressive and violent behavior in critical care settings increases the likelihood that clinicians working in this environment will encounter this situation. It is our hope that providing additional information about the factors associated with and techniques for managing violent patient behavior will reduce the occurrence of injuries in health care professionals in emergency departments.

Clinical Toxicology and Management of Intoxications With Synthetic Cathinones (“Bath Salts”)

Synthetic cathinones are synthetic derivatives of the natural cathinone, one of the psychoactive compounds present in Catha edulis (khat). There are at least 12 different types of synthetic cathinones, with mephedrone and 3,4-methylendioxypyrovalerone (MDPV) being the most commonly used by the purchasers. The legal control of these substances is especially difficult because when a specific compound is banned, a new slightly modified chemical variant is introduced into the market. It has been described that patients after taking synthetic cathinones may show signs and symptoms of the sympathicomimetic toxidrome, including agitation, psychosis, tachycardia, hypertension, and seizures. Furthermore, some cases of deaths related to their consumption have also been reported. Nowadays, there is no established treatment protocol for the clinical management of these intoxications. Because of this, we have developed some recommendations that may be useful to determine the treatment of these patients.

Examination of baseline risk factors for QTc interval prolongation in patients prescribed intravenous haloperidol

BACKGROUND

Intravenous haloperidol can increase the risk for corrected QT interval (QTc) prolongation, torsades de pointes (TdP) and sudden death. There are a number of risk factors reported in the literature for QTc prolongation and TdP with intravenous haloperidol.

OBJECTIVE

The purpose of this study was to determine the prevalence of baseline risk factors for QTc prolongation and TdP in hospitalized medical inpatients prescribed intravenous haloperidol.

METHODS

This is a retrospective cohort study of medically ill hospitalized inpatients prescribed intravenous haloperidol between 30 June 2007 and 1 January 2010. Records were ascertained for the presence of baseline risk factors for QTc prolongation and TdP.

RESULTS

A total of 175 subjects were identified as receiving intravenous haloperidol during the study period. Mean age was 62.9 ± 19.1 years, and 48.6% of subjects were female. At baseline, 85.7% of subjects had ≥1 risk factor for QTc prolongation and TdP, with the majority of these subjects (58.0%) having between two and five risk factors. Of the total study sample, 74.9% had a baseline ECG; mean QTc value was 457 msec (± 40.8 msec). Greater than 50% of subjects had a sex-specific QTc value higher than the increased risk threshold of 450 msec in males or 460 msec in females at baseline. Following intravenous haloperidol administration, 46.9% of subjects had a follow-up ECG obtained within 24 hours. At the time of intravenous haloperidol administration, 93.1% of subjects had a potassium value available and 62.9% had a magnesium value. Approximately 30% of subjects had either a potassium or magnesium value below the normal laboratory range. Of the 175 subjects, 43.4% were taking ≥1 concomitant QTc prolongation medication at the time of intravenous haloperidol administration.

CONCLUSIONS

Consistent with previously published reports, patients in this study prescribed intravenous haloperidol had multiple risk factors, both modifiable and non-modifiable, at baseline for QTc prolongation and TdP. The modifiable risk factors may be important targets of interventions aimed at optimizing the safety of the use of intravenous haloperidol, while the non-modifiable risk factors may warrant closer scrutiny with consideration of alternative therapies and continuous monitoring.