Christian Tomaszewski

Insulin-glucose as adjunctive therapy for severe calcium channel antagonist poisoning.

CASE REPORT This case series documents the clinical courses of 4 patients after verapamil overdose and 1 patient after amlodipine-atenolol overdose. All subjects had hypodynamic circulatory shock (hypotension, bradycardia, and acidosis) that was not adequately responsive to conventional treatment. After initiation of insulin-dextrose infusion, the hemodynamic status of all 5 patients stabilized and all patients survived. Plasma drug concentrations are reported for all cases and verapamil levels were extremely high in 2 patients (3710 ng/mL and 3980 ng/mL). However, because patients were not treated according to a standard protocol, each patient received variable other supportive measures and inotropic agents, and the infusion rates of insulin were variable among patients. This report provides preliminary evidence toward a larger trial of insulin-dextrose to treat hypodynamic shock from calcium channel blocker overdose.

Insulin Improves Survival in a Canine Model of Acute β-Blocker Toxicity

STUDY OBJECTIVE To compare the efficacy of a novel antidote, insulin, with standard treatments, glucagon and epinephrine, in a canine model of acute beta-blocker toxicity. METHODS Anesthetized dogs were fitted with instruments by means of thoracotomy and vascular cutdown for multiple cardiodynamic, hemodynamic, metabolic, and electrical measures. After basal measurements were taken, animals received intravenous propranolol (.25 mg/kg/minute) continuously for the remainder of the experiment. Toxicity was defined as a 25% decrease in the product of heart rate times mean blood pressure. Thirty minutes after the development of toxicity, toxic measures were taken (treatment 0 minutes), and then the animals (n = 6 each group) received either sham (saline solution), insulin (4 IU/minute with glucose clamped), glucagon (50 micrograms/kg bolus, then 150 micrograms/kg/hour infusion), or epinephrine (1 microgram/kg/minute). Animals were monitored until death or for 240 minutes. RESULTS Propranolol decreased contractility, left ventricular pressure, and systemic blood pressure, and resulted in death of all sham-treated animals by 150 minutes. Six of six insulin-treated, four of six glucagon-treated, and one of six epinephrine-treated animals survived. Survival was greater for insulin-treated animals, compared with either glucagon-treated (P < .05) or epinephrine-treated animals (P < .02) by the log-rank test. Insulin-treated animals were characterized by improved cardiodynamics and hemodynamics, increased myocardial glucose uptake, and decreased serum potassium. CONCLUSION Insulin is a superior antidote compared with glucagon or epinephrine in an anesthetized canine model of acute beta-blocker toxicity.

FAST (Focused Assessment With Sonography in Trauma) Accurate for Cardiac and Intraperitoneal Injury in Penetrating Anterior Chest Trauma

Objective. To evaluate the FAST (focused assessment with sonography in trauma) examination for determining traumatic pericardial effusion and intraperitoneal fluid indicative of injury in patients with penetrating anterior chest trauma. Methods. An observational prospective study was conducted over a 30‐month period at an urban level I trauma center. FAST was performed in the emergency department by emergency physicians and trauma surgeons. FAST results were recorded before review of patient outcome as determined by 1 or more of the following: thoracotomy, laparotomy, pericardial window, cardiologic echocardiography, diagnostic peritoneal lavage, computed tomography, and serial examinations. Results. FAST was undertaken in 32 patients with penetrating anterior chest trauma: 20 (65%) had stab wounds, and 12 (35%) had gunshot wounds. Sensitivity of FAST for cardiac injury (n = 8) in patients with pericardial effusion was 100% (95% confidence interval, 63.1%–100%); specificity was 100% (95% confidence interval, 85.8%–100%). The presence of pericardial effusion determined by FAST correlated with the need for thoracotomy in 7 (87.5%) of 8 patients (95% confidence interval, 47.3%–99.7%). One patient with a pericardial blood clot on cardiologic echocardiography was treated nonsurgically. FAST had 100% sensitivity for intraperitoneal injury (95% confidence interval, 63.1%–100%) in 8 patients with views indicating intraperitoneal fluid but without pericardial effusion, again with no false‐positive results, giving a specificity of 100% (95% confidence interval, 85.8%–100%). This prompted necessary laparotomy in all 8. Conclusions. In this series of patients with penetrating anterior chest trauma, the FAST examination was sensitive and specific in the determination of both traumatic pericardial effusion and intraperitoneal fluid indicative of injury, thus effectively guiding emergent surgical decision making.

Glycolate Kinetics and Hemodialysis Clearance in Ethylene Glycol Poisoning

OBJECTIVE Toxic manifestations following ethylene glycol exposure are due to accumulation of metabolites, particularly glycolate. We characterized glycolate elimination kinetics and dialysis properties in a series of ethylene glycol poisonings. METHODS Patients who ingested ethylene glycol and received fomepizole (4-methylpyrazole; 4-MP) +/- hemodialysis were prospectively evaluated. Serial blood samples for ethylene glycol, glycolate, pH, and bicarbonate were drawn to determine glycolate elimination rate, t1/2, and correlations between initial glycolate and initial markers of acidosis. Dialyzer inlet and outlet samples were obtained to measure hemodialysis glycolate clearance. Plasma ethylene glycol and glycolate were determined by gas chromatography. RESULTS Ten patients, mean age 49 years (range 28-73 years), presented a mean of 10.5 hours (range 3.5-21.5 hours) after ethylene glycol ingestion. Mean initial ethylene glycol was 18.5 mmol/L (range 0.8-62.2 mmol/L) (115 mg/dL; range 5-386 mg/dL) and glycolate was 17.0 mmol/L (range 10.0-23.7 mmol/L). Nine of 10 underwent hemodialysis. Nonhemodialysis (n = 4) elimination rate was 1.08 +/- 0.67 mmol/L/h (mean +/- SD) and t1/2 was 626 +/- 474 minutes. Elimination t1/2 during hemodialysis (n = 8) was 155 +/- 42 minutes. Hemodialysis clearance (n = 5) was 170 +/- 23 mL/min with flow rates 250-400 mL/min. Pearson correlation coefficients were: anion gap vs glycolate r2 = 0.65 (p = 0.005), bicarbonate vs glycolate r2 = 0.10 (NS) and pH vs glycolate r2 = 0.06 (NS). CONCLUSION Glycolate has a slow elimination rate and long half-life. Hemodialysis effectively clears glycolate. An increased anion gap correlates with the presence of glycolate. Hemodialysis is projected as useful for ethylene glycol-poisoned patients with anion gap acidosis and low ethylene glycol blood levels.

Formate Kinetics in Methanol Poisoning

Objective: We sought to describe the kinetics, dialysis clearance, and laboratory markers of formate (FA), the toxic metabolite of methanol (meOH). Methods: Data were obtained from a prospective, multicenter study of fomepizole±dialysis for methanol poisoning. Inclusion criteria confirmed methanol exposure or suspicion of exposure plus either acidemia or abnormal osmolar gap. Dialysis indications were [meOH]>50 mg/dL, pH<7.1, refractory acidosis, or visual toxicity. Serial plasma formate, methanol, pH, and electrolyte measurements were made. Formate was determined by gas chromatography. Endogenous and dialysis elimination half-lives were calculated as t1/2=0.693/Ke, with Ke (elimination constant) derived from the slope of log (FA) vs. time. Half-lives were compared with an unpaired Students t-test. Dialysis clearance was calculated using the Fick Principle. Pearson correlation analysis compared initial formate with initial pH, serum bicarbonate, and anion gap. Results: Eleven patients were treated in the study. Eight had detectable formate with mean [FA] of 15.1 mmol/L (range 0.5–34.8). Endogenous elimination half-life was 205±90 minutes. Elimination half-life during dialysis (n=5) was 150±37 minutes, which was not different (t=0.22; NS). The overall dialysis formate clearance rate was 223±25 mL/min. Correlation coefficients were: pH vs. formate r2=0.93; bicarbonate vs. formate r2=0.81; and anion gap vs. formate r2=0.76 (all p<0.05). Conclusions: Although dialysis clears formate, it did not significantly enhance endogenous elimination in our series of patients. Low pH, low bicarbonate, and elevated anion gap correlate independently with formate presence.

INCIDENCE OF ASPIRATION PNEUMONIA IN INTUBATED PATIENTS RECEIVING ACTIVATED CHARCOAL

Several case reports and animal studies raise concerns over the risk of aspiration pneumonia when administering activated charcoal (AC) to intubated patients. Therefore, we sought to determine the incidence of aspiration pneumonia in intubated overdose patients who then received AC. We conducted a retrospective review from January 1994 to April 1997 of intubated patients who then received AC. Patients were transferred to, or primarily treated at, an 843-bed tertiary medical center with an annual emergency department volume of 100,000 patients. Objective evidence of infiltrate on chest radiograph during initial 48 h of hospitalization was used to determine the incidence of aspiration pneumonia. Patients with known preexisting pneumonia or with administration of AC before intubation were excluded. There were 64 patients identified. Fourteen were excluded for clinical aspiration before intubation, receiving activated charcoal before intubation, or abnormal immediate post-intubation chest radiographs. The remaining 50 patients, ages 1-64 years, 33% male, overdosing on a large variety of substances, required acute intubation and then received AC. Only two patients of these 50 (4%) with initial negative radiographs developed a new infiltrate after intubation and AC. Administration of AC to intubated overdose patients is associated with a low incidence of aspiration pneumonia.

Evidence-Based Treatment of Jellyfish Stings in North America and Hawaii

We performed a systematic review of the evidence supporting various treatments for envenomation by jellyfish (cnidarian) and related organisms in North America and Hawaii. Our review produced 19 pertinent primary articles. Current research demonstrates variable response to treatment, often with conflicting results according to species studied, which contributes to considerable confusion about what treatment is warranted and efficacious. Our review suggests that vinegar causes pain exacerbation or nematocyst discharge in the majority of species. Hot water and topical lidocaine appear more widely beneficial in improving pain symptoms and are preferentially recommended. Unfortunately, they may be difficult to obtain at the site of envenomation, such as the beach or diving sites. In these instances, removing the nematocysts and washing the area with saltwater may be considered. If the envenomation is thought to be due to the bluebottle (Physalia), vinegar may be beneficial.

Clinical Policy: Critical Issues in the Evaluation and Management of Adult Patients Presenting to the Emergency Department With Seizures

This clinical policy from the American College of Emergency Physicians is the revision of a 2004 policy on critical issues in the evaluation and management of adult patients with seizures in the emergency department. A writing subcommittee reviewed the literature to derive evidence-based recommendations to help clinicians answer the following critical questions: (1) In patients with a first generalized convulsive seizure who have returned to their baseline clinical status, should antiepileptic therapy be initiated in the emergency department to prevent additional seizures? (2) In patients with a first unprovoked seizure who have returned to their baseline clinical status in the emergency department, should the patient be admitted to the hospital to prevent adverse events? (3) In patients with a known seizure disorder in which resuming their antiepileptic medication in the emergency department is deemed appropriate, does the route of administration impact recurrence of seizures? (4) In emergency department patients with generalized convulsive status epilepticus who continue to have seizures despite receiving optimal dosing of a benzodiazepine, which agent or agents should be administered next to terminate seizures? A literature search was performed, the evidence was graded, and recommendations were given based on the strength of the available data in the medical literature.

Urine toxicology screens in drivers suspected of driving while impaired from drugs

OBJECTIVE Police departments, in conjunction with the National Highway Traffic Safety Administration, have developed a standardized evaluation aimed at identifying drivers impaired by drugs other than ethanol. These evaluations are performed by specially trained police officers known as Drug Recognition Experts. METHODS We retrospectively reviewed the evaluations of 242 drivers detained for driving while impaired in the City and County of Denver from January 1, 1988 to June 30, 1990. RESULTS All drivers had urine toxicology screens performed, which were positive for a mean 1.2 +/- 0.9 SD (range zero to four) for drugs having the potential for causing driving impairment. The 193/242 urine screens (79.8%) testing positive showed the following drugs: cannabis 162 (66.9%), stimulants (including cocaine metabolites) 80 (33.1%), depressants (benzodiazepines and barbiturates) 24 (9.9%), narcotics 12 (5.0%), inhalants (toluene) 1 (0.4%), hallucinogens (LSD) 1 (0.4%), and other 3 (1.2%). Drug Recognition Experts, based on their initial evaluation, were able to predict correctly some or all of the drugs found on the urine screens in 178/242 (73.6%) of cases. Overall agreement between the Drug Recognition Experts opinions and urine screen results had a kappa value (p < 0.05) of 0.41. CONCLUSIONS There was a high rate (79.8%) of positive urine toxicology screens in drivers suspected of nonethanol drug impairment. In most cases, Drug Recognition Experts were able to reliably predict the results of these screens.

Spontaneous hemoperitoneum from brodifacoum overdose

Brodifacoum is a 4-hydroxycoumarin derivative that is commonly used as a rodenticide. Human exposures have produced severe coagulopathies resulting in hematuria, gastrointestinal bleeding, intracranial hemorrhage, and death. This is the first report of spontaneous hemoperitoneum secondary to brodifacoum ingestion. The patient was successfully managed with fresh frozen plasma, packed red blood cells, and vitamin K1. No surgical intervention was performed. The patient required ongoing daily vitamin K1 therapy for longer than 6 months.