Colin B. Page

Randomized controlled trial of intramuscular droperidol versus midazolam for violence and acute behavioral disturbance: the DORM study.

STUDY OBJECTIVE We determine whether droperidol, midazolam, or the combination is more effective for intramuscular sedation in violent and acute behavioral disturbance in the emergency department (ED). METHODS We conducted a blinded randomized controlled trial of intramuscular sedation for violent and acute behavioral disturbance, comparing droperidol (10 mg), midazolam (10 mg), and droperidol (5 mg)/midazolam (5 mg). Inclusion criteria were patients requiring physical restraint and parenteral sedation. The primary outcome was the duration of the violent and acute behavioral disturbance, defined as the time security staff were required. Secondary outcomes included time until additional sedation was administered, staff and patient injuries, further episodes of violent and acute behavioral disturbance, and drug-related adverse effects. RESULTS From 223 ED patients with violent and acute behavioral disturbance, 91 patients were included; 33 received droperidol, 29 received midazolam, and 29 received the combination. There was no difference in the median duration of the violent and acute behavioral disturbance: 20 minutes (interquartile range [IQR] 11 to 37 min) for droperidol, 24 minutes (IQR 13 to 35 minutes) for midazolam, and 25 minutes (IQR 15 to 38 minutes) for the combination. Additional sedation was required in 11 (33%; 95% confidence interval [CI] 19% to 52%) droperidol patients, 18 (62%; 95% CI 42% to 79%) midazolam patients, and 12 (41%; 95% CI 24% to 61%) in the combination group. The hazard ratio for additional sedation in the midazolam versus droperidol group was 2.31 (95% credible interval 1.01 to 4.71); for the combination versus droperidol, 1.18 (95% credible interval 0.46 to 2.50). Patient and staff injuries and number of further episodes of violent and acute behavioral disturbance did not differ between groups. There were two adverse effects for droperidol (6%; 95% CI 1% to 22%), 8 for midazolam (28%; 95% CI 13% to 47%), and 2 for the combination (7%; 95% CI 1% to 24%). An abnormal QT occurred in 2 of 31 (6%; 95% CI 1% to 23%) droperidol patients, which was not different from the other groups. CONCLUSION Intramuscular droperidol and midazolam resulted in a similar duration of violent and acute behavioral disturbance, but more additional sedation was required with midazolam. Midazolam caused more adverse effects because of oversedation, and there was no evidence of QT prolongation associated with droperidol compared with midazolam.

Clinical Effects and Antivenom Dosing in Brown Snake (Pseudonaja spp.) Envenoming — Australian Snakebite Project (ASP-14)

Background Snakebite is a global health issue and treatment with antivenom continues to be problematic. Brown snakes (genus Pseudonaja) are the most medically important group of Australian snakes and there is controversy over the dose of brown snake antivenom. We aimed to investigate the clinical and laboratory features of definite brown snake (Pseudonaja spp.) envenoming, and determine the dose of antivenom required. Methods and Finding This was a prospective observational study of definite brown snake envenoming from the Australian Snakebite Project (ASP) based on snake identification or specific enzyme immunoassay for Pseudonaja venom. From January 2004 to January 2012 there were 149 definite brown snake bites [median age 42y (2–81y); 100 males]. Systemic envenoming occurred in 136 (88%) cases. All envenomed patients developed venom induced consumption coagulopathy (VICC), with complete VICC in 109 (80%) and partial VICC in 27 (20%). Systemic symptoms occurred in 61 (45%) and mild neurotoxicity in 2 (1%). Myotoxicity did not occur. Severe envenoming occurred in 51 patients (38%) and was characterised by collapse or hypotension (37), thrombotic microangiopathy (15), major haemorrhage (5), cardiac arrest (7) and death (6). The median peak venom concentration in 118 envenomed patients was 1.6 ng/mL (Range: 0.15–210 ng/mL). The median initial antivenom dose was 2 vials (Range: 1–40) in 128 patients receiving antivenom. There was no difference in INR recovery or clinical outcome between patients receiving one or more than one vial of antivenom. Free venom was not detected in 112/115 patients post-antivenom with only low concentrations (0.4 to 0.9 ng/ml) in three patients. Conclusions Envenoming by brown snakes causes VICC and over a third of patients had serious complications including major haemorrhage, collapse and microangiopathy. The results of this study support accumulating evidence that giving more than one vial of antivenom is unnecessary in brown snake envenoming.

Structured team approach to the agitated patient in the emergency department

Objective:  Behavioural disturbance and aggression in the ED is an increasing problem. The present study describes the characteristics of patients with acute behavioural disturbance and their emergent treatment in an ED with a structured team approach.

The use of high-dose insulin-glucose euglycemia in beta-blocker overdose: A case report

The management of life-threatening beta-blocker toxicity and its associated low cardiac output state is clinically challenging. Previous case reports and case series describe the use of hyperinsulinemia/euglycemia therapy in mono-ingestions of calcium channel blockers and mixed ingestions, including calcium channel and beta-blockers. In this case report we describe the use of high-dose insulin (10 IU/kg per hour) in a case of massive metoprolol ingestion (5 g) in which hypotension was unresponsive to conventional therapies. Although the metoprolol concentrations measured in plasma were approximately 100–200 times therapeutic concentrations, the pharmacokinetics appeared to be similar to therapeutic metoprolol dosing.

The Safety and Effectiveness of Droperidol for Sedation of Acute Behavioral Disturbance in the Emergency Department.

STUDY OBJECTIVE We investigate the safety and effectiveness of droperidol for sedation of acute behavioral disturbance in the emergency department (ED). METHODS This was a prospective observational study in 6 EDs (August 2009 to April 2013). Adult patients requiring parenteral sedation for acute behavioral disturbance received droperidol 10 mg. If this did not sedate the patient within 15 minutes, further sedation was allowed but droperidol 10 mg was recommended as part of a sedation protocol. The primary outcome was the proportion of patients with an abnormal QT interval, defined by the at-risk line on the QT nomogram. Secondary outcomes were effectiveness determined by the time to sedation measured on the Sedation Assessment Tool, use of additional sedation, adverse events, and injury to staff or patients. RESULTS There were 1,009 patients with an ECG performed within 2 hours of droperidol administration, with a median dose of 10 mg (interquartile range [IQR]10 to 17.5 mg). Thirteen of the 1,009 patients had an abnormal QT (1.3%; 95% confidence interval 0.7% to 2.3%), but 7 of these had another cause attributed for prolonged QT (methadone, escitalopram, amiodarone, or preexisting). In 1,403 patients sedated with a median total dose of droperidol of 10 mg (IQR 10 to 20 mg), the median time to sedation was 20 minutes (IQR 10 to 30 minutes) and 97% were sedated within 120 minutes. Additional sedation was required for 435 patients (31.0%; 95% confidence interval 28.6% to 33.5%). Adverse events occurred in 70 patients (5%) and oversedation without complications in 109 (8%), the latter more common for patients receiving benzodiazepines as additional sedation (16/109 [15%]). There were no cases of torsades de pointes. Injuries occurred in 34 staff members and 4 patients. CONCLUSION The study supports the use of high-dose droperidol as a safe sedating agent for patients with acute behavioral disturbance in the ED. There is no evidence of increased risk for QT prolongation with the doses used in this study.

Snakebite in Australia: a practical approach to diagnosis and treatment

Snakebite is a potential medical emergency and must receive high‐priority assessment and treatment, even in patients who initially appear well. Patients should be treated in hospitals with onsite laboratory facilities, appropriate antivenom stocks and a clinician capable of treating complications such as anaphylaxis. All patients with suspected snakebite should be admitted to a suitable clinical unit, such as an emergency short‐stay unit, for at least 12 hours after the bite. Serial blood testing (activated partial thromboplastin time, international normalised ratio and creatine kinase level) and neurological examinations should be done for all patients. Most snakebites will not result in significant envenoming and do not require antivenom. Antivenom should be administered as soon as there is evidence of envenoming. Evidence of systemic envenoming includes venom‐induced consumption coagulopathy, sudden collapse, myotoxicity, neurotoxicity, thrombotic microangiopathy and renal impairment. Venomous snake groups each cause a characteristic clinical syndrome, which can be used in combination with local geographical distribution information to determine the probable snake involved and appropriate antivenom to use. The Snake Venom Detection Kit may assist in regions where the range of possible snakes is too broad to allow the use of monovalent antivenoms. When the snake identification remains unclear, two monovalent antivenoms (eg, brown snake and tiger snake antivenom) that cover possible snakes, or a polyvalent antivenom, can be used. One vial of the relevant antivenom is sufficient to bind all circulating venom. However, recovery may be delayed as many clinical and laboratory effects of venom are not immediately reversible. For expert advice on envenoming, contact the National Poisons Information Centre on 13 11 26.

Randomized controlled trial of intravenous antivenom versus placebo for latrodectism: The second redback antivenom evaluation (RAVE-II) study

STUDY OBJECTIVE Latrodectism is the most important spider envenomation syndrome worldwide. There remains considerable controversy over antivenom treatment. We aimed to investigate whether antivenom resulted in resolution of pain and systemic effects in patients with latrodectism who received standardized analgesia. METHODS In a multicenter randomized placebo-controlled trial of redback spider antivenom for latrodectism, 224 patients (>7 years) with a redback spider bite and severe pain, with or without systemic effects, were randomized to receive normal saline solution (placebo) or antivenom after receiving standardized analgesia. The primary outcome was a clinically significant reduction in pain 2 hours after trial medication compared with baseline. A second primary outcome for the subgroup with systemic features of envenomation was resolution of systemic features at 2 hours. Secondary outcomes were improved pain at 4 and 24 hours, resolution of systemic features at 4 hours, administration of opioid analgesics or unblinded antivenom after 2 hours, and adverse reactions. RESULTS Two hours after treatment, 26 of 112 patients (23%) from the placebo arm had a clinically significant improvement in pain versus 38 of 112 (34%) from the antivenom arm (difference in favor of antivenom 10.7%; 95% confidence interval -1.1% to 22.6%; P=.10). Systemic effects resolved after 2 hours in 9 of 41 patients (22%) in the placebo arm and 9 of 35 (26%) in the antivenom arm (difference 3.8%; 95% confidence interval -15% to 23%; P=.79). There was no significant difference in any secondary outcome between antivenom and placebo. Acute systemic hypersensitivity reactions occurred in 4 of 112 patients (3.6%) receiving antivenom. CONCLUSION The addition of antivenom to standardized analgesia in patients with latrodectism did not significantly improve pain or systemic effects.

Risperidone Overdose Causes Extrapyramidal Effects But Not Cardiac Toxicity

Objective: The aim of this study was to describe the clinical and electrocardiographic features of risperidone overdose, including the frequency of dystonic reactions. Methods: A consecutive series of admissions for risperidone overdose (>6 mg) were identified from a prospective database of poisoning admissions to a regional toxicology service. Data extracted included patient demographics, details of ingestion, clinical features including neurological findings and evidence of dystonias, electrocardiographic parameters (heart rate [HR], QRS, and QT intervals), complications, and medical outcomes including intensive care unit admission. In addition to descriptive statistics, visual inspection of plots of QT-HR pairs compared with the QT nomogram was performed. Results: There were 107 patients with 157 presentations, including 38 patients with 45 risperidone-alone overdoses. Of the 38 patients who ingested risperidone alone, the median age was 25 years (interquartile range [IQR],16-31 years), and 19 (50%) were female. The median dose ingested was 33 mg (IQR, 15-75 mg; range, 8-248 mg). Median length of stay was 16 hours (IQR, 8-18 hours), and none was ventilated or admitted to the intensive care unit. There were 5 cases (11%) with dystonic reactions, 26 (58%) with tachycardia (HR ≥100 beats/min), and no cases with hypotension (blood pressure <90 mm Hg). Only 1 patient (2%) recorded a decreased Glasgow Coma Scale score of 14, and there were no seizures or deaths. On review of electrocardiograms in 41 of the 45 cases where risperidone was ingested alone, there were no acute dysrhythmias. In 4 electrocardiograms (10%), there was an abnormal QT-HR pair, but all bar one were associated with an HR of greater than 110 beats/min. The median maximum QRS width was 80 milliseconds (IQR, 80-80 milliseconds; range, 40-120 milliseconds). Conclusions: Risperidone taken alone in overdose causes minimal effects. Tachycardia and dystonic reactions were the main features of toxicity. Significant cardiac and other neurological features seem to be uncommon.

The impact of a standardised intramuscular sedation protocol for acute behavioural disturbance in the emergency department

BackgroundAcute behavioural disturbance (ABD) is an increasing problem in emergency departments. This study aimed to determine the impact of a structured intramuscular (IM) sedation protocol on the duration of ABD in the emergency department.MethodsA historical control study was undertaken comparing 58 patients who required physical restraint and parenteral sedation with the structured IM sedation protocol, to 73 historical controls treated predominantly by intravenous sedation, according to individual clinician preference. The primary outcome was the duration of the ABD defined as the time security staff were required. Secondary outcomes were the requirement for additional sedation, drug related-adverse effects and patient and staff injuries.ResultsThe median duration of the ABD in patients with the new sedation protocol was 21 minutes (IQR: 15 to 35 minutes; Range: 5 to 78 minutes) compared to a median duration of 30 minutes (IQR: 15 to 50 minutes; Range: 5 to 135 minutes) in the historical controls which was significantly different (p = 0.03). With IM sedation only 27 of 58 patients (47%; 95% CI: 34% to 60%) required further sedation compared to 64 of 73 historical controls (88%; 95%CI: 77% to 94%). There were six (10%) drug-related adverse events with the new IM protocol [oxygen desaturation (5), oxygen desaturation/airway obstruction (1)] compared to 10 (14%) in the historical controls [oxygen desaturation (5), hypoventilation (4) and aspiration (1)]. Injuries to staff occurred with three patients using the new sedation protocol and in seven of the historical controls. Two patients were injured during the new protocol and two of the historical controls.ConclusionThe use of a standardised IM sedation protocol was simple, more effective and as safe for management of ABD compared to predominantly intravenous sedation.

A prospective observational study of a novel 2-phase infusion protocol for the administration of acetylcysteine in paracetamol poisoning

Abstract Context: The current 3-phase acetylcysteine infusion for paracetamol poisoning delivers half the dose over 15–60 min and frequently results in adverse reactions. Objective: We aimed to determine adverse reaction frequency with a modified 2-phase infusion protocol with a longer initial infusion. Materials and methods: A prospective observational study of a modified 2-phase acetylcysteine protocol was undertaken at two hospitals. Acetylcysteine was commenced on admission and ceased if paracetamol concentrations were low-risk (below the nomogram line). The first infusion was 200 mg/kg over 4–9 h based on ingestion time or 4 h for staggered/chronic ingestions. The second infusion was 100 mg/kg over 16 h. Pre-defined outcomes were frequency of adverse reactions (systemic hypersensitivity reactions or gastrointestinal); proportion with alanine transaminase (ALT) > 1000 U/L or abnormal ALT. Results: 654 paracetamol poisonings were treated with the new protocol; median age 29 y (15–98 y); 453 females; 576 acute and 78 staggered/chronic ingestions. In 420 (64%) acetylcysteine was stopped for low-risk paracetamol concentrations. An adverse reaction occurred in 229/654 admissions (35%; 95% CI: 31–39%): 173 (26.5%; 95% CI: 23–30%) only gastrointestinal, 50 (8%; 95% CI: 6–10%) skin only systemic hypersensitivity reactions; and three severe anaphylaxis (0.5%; 95% CI: 0.1–1.5%; all hypotension). Adverse reactions occurred in 111/231 (48%) receiving full treatment compared to 116/420 (28%) in whom the infusion was stopped early (absolute difference 20%; 95% CI: 13–28%; p < 0.0001). In 200 overdoses < 10 g, one had toxic paracetamol concentrations, but 53 developed reactions. Sixteen patients had an ALT > 1000 U/L and 24 an abnormal ALT attributable to paracetamol; all but one had treatment commenced >12 h post-ingestion. Conclusion: A 2-phase acetylcysteine infusion protocol results in a fewer reactions in patients with toxic paracetamol concentrations, but is not justified in patients with low-risk paracetamol concentrations.