Louis J. Ling

Whole-bowel irrigation as a treatment for acute lithium overdose

STUDY OBJECTIVE To determine if gastrointestinal decontamination using whole-bowel irrigation (WBI) was an effective treatment for acute ingestion of sustained-release lithium. METHODS In a two-phase, crossover protocol, ten normal volunteers ingested in each phase 0.80 mEq/kg sustained-release lithium carbonate. In the second phase, WBI was begun one hour after lithium ingestion, and 10 L of polyethylene glycol solution were administered over five hours. Serum samples were collected every half hour for six hours, every hour for an additional six hours, and then every 24 hours for as long as 72 hours after ingestion. These samples were analyzed for lithium concentration. The area under the lithium serum concentration-versus-time curve was calculated for each phase. RESULTS The average area under the lithium serum concentration-versus-time curve in the WBI phase was 67% +/- 11% less than that in the control phase (P less than .0005 using a two-tailed Students t test). The mean serum lithium concentration was significantly decreased (P = .03) within one hour of beginning WBI. CONCLUSION WBI is an effective treatment for acute ingestion of sustained-release lithium. We recommend it as the decontaminant procedure of choice in this situation.

Duration of antagonistic effects of nalmefene and naloxone in opiate-induced sedation for emergency department procedures

Naloxone is an effective opiate antagonist, but its short half-life limits its usefulness. For outpatient procedures, a longer acting opiate antagonist could eliminate two to four hours of nursing observation in patients postoperatively. A controlled, randomized, double-blind trial comparing the effects of nalmefene, naloxone, and placebo in reversing opiate-induced sedation was carried out to determine efficacy, duration of action, and adverse effects in patients undergoing outpatient procedures. Each patient received 1.5 to 3.0 mg/kg meperidine intravenously before the procedure. After the procedure, each patient received either nalmefene, 1.0 mg; naloxone, 1.0 mg; or saline, 1.0 mL intravenously. Vital signs and assessments for alertness were performed for four hours. Naloxone significantly reversed sedation for only 15 minutes, whereas nalmefene was significantly effective (P less than .05) for up to 210 minutes. Nalmefene was significantly more effective than naloxone in reversing sedation at 60, 90, and 120 minutes. Nalmefene is an effective agent for the reversal of opiate-induced sedation after outpatient procedures.

Survival following hydrofluoric acid ingestion

Systemic toxicity after significant dermal exposure to hydrofluoric acid includes rapid development of hypocalcemia and hyperkalemia, leading to ventricular fibrillation. Similar dysrhythmias have occurred in patients after ingestion of sodium fluoride-containing compounds. Ingestion of hydrofluoric acid could induce similar cardiac toxicity; however, reported cases of hydrofluoric acid ingestion rarely have been described, and the rapid death of these patients has not allowed verification of this hypothesis. On two separate occasions, a 70-year-old woman ingested up to 2 oz of a 8% hydrofluoric acid-containing solution. Recurrent ventricular fibrillation with concurrent hypocalcemia and hypomagnesemia complicated her first episode, whereas a more aggressive administration of calcium and magnesium may have prevented dysrhythmias in the second episode. Survival from ventricular fibrillation after hydrofluoric acid ingestion has not been reported previously and suggests a role for aggressive empiric calcium and magnesium replacement.

Diltiazem overdose: case report and review

We present a case of diltiazem overdose in which the patient ingested 4.2 grams in an apparent suicide attempt. He arrived in the emergency department two hours postingestion with a blood pressure of 60/40 torr and a heart rate of 62 beats/min in a junctional rhythm. Intervention included activated charcoal, gastric lavage, intravenous fluids, calcium (both chloride and gluconate), dopamine, and atropine with improvement in vital signs. Diltiazem levels were obtained and half-life calculated. This ingestion is one of the largest reported in the literature and is remarkable in that the patient recovered without pacing or other extraordinary measures. All eight previously published cases of diltiazem overdose, including all unpublished reports to the manufacturer, are reviewed and their management strategies examined. Successful treatment in which recovery has occurred in less than 48 hours, includes pressors, calcium, glucagon, pacing, and charcoal hemoperfusion. A strategy for emergency physicians to use when approaching this problem is suggested from the review.

The effects of fluoxetine in the overdose patient

Fluoxetine (Prozac) is a new antidepressant, first marketed in the United States in January 1988. Only limited toxicologic information during a fluoxetine overdose is available. The goal of this prospective multi-center study was to develop a toxicity profile of initial signs and symptoms observed in fluoxetine overdose. A standardized data collection form was used on all patients ingesting fluoxetine as reported to four poison centers. Information obtained included age, dose, co-ingested drugs, presenting symptoms, vital signs, EKG abnormalities and lab values. Of the 127 cases of acute fluoxetine overdose collected, 106 cases met the criteria of the study. Of these, 69/106 ingested other drugs, including ethanol and 37/106 ingested fluoxetine alone. Of the latter group, the amounts ingested ranged from 20 to 1500 mg. It was observed that 48.6% (18/37) remained asymptomatic, 16.2% (7/37) were sleepy, 24.3% (9/37) had a sinus tachycardia (of 100 beats per minute or greater), and 8.1% (3/37) had a diastolic pressure over 100 mm Hg. Data collection is ongoing. Based upon our initial experience, fluoxetine in overdose appears to be relatively benign.

Safety assessment of high-dose narcotic analgesia for emergency department procedures

STUDY OBJECTIVE To evaluate the safety of high-dose IV narcotics in patients requiring analgesia for painful emergency department procedures. DESIGN Prospective multicenter clinical trial. SETTING Five adult urban EDs. METHODS AND MEASUREMENTS All patients received IV meperidine (1.5 to 3.0 mg/kg) titrated to analgesia followed by a painful procedure. Vital signs and alertness scale were recorded at regular intervals, and patients were observed for four hours. Adverse events were monitored and documented. Comparisons between baseline and postanalgesia intervals were made with a repeated measures ANOVA (Dunnetts test). RESULTS Although statistically significant changes in vital signs and alertness scale occurred, they were not clinically significant. Opiate reversal with naloxone was not needed in any patient, and no significant respiratory or circulatory compromise occurred. CONCLUSION This study of 72 patients demonstrates that high-dose narcotic analgesia is appropriate, well tolerated, and safe when used in selected patients before painful procedures in the ED. Narcotic antagonists and resuscitation equipment nonetheless should be available to maximize safety.

Research directions in emergency medicine

Abstract The goal of emergency medicine is to improve health while preventing and treating disease and illness in patients seeking emergency medical care. Improvements in emergency medical care and the delivery of this care can be achieved through credible and meaningful research efforts. Improved delivery of emergency medical care through research requires careful planning and the wise use of limited resources. To achieve this goal, emergency medicine must provide appropriate training of young investigators and attract support for their work. Promotion of multidisciplinary research teams will help the specialty fulfill its goals. The result will be the improvement of emergency medical care which will benefit not only the patients emergency physicians serve but also, ultimately, the nations health.

The Effect of Oral Deferoxamine on Iron Absorption in Humans

Acute iron overdose is a serious cause of morbidity and mortality, however, optimal gastric decontamination procedures in iron overdose are unclear. In order to determine the effectiveness of oral deferoxamine mesylate solution in humans to prevent the absorption of iron in acute exposures, the following prospective case control crossover study was designed. Seven informed adult human volunteers were given an oral dose of 5 mg/kg elemental iron alone in a control phase and again in an experimental phase followed by a single equimolar dose of oral buffered deferoxamine solution. Plasma iron concentrations were determined spectrophotometrically for eight hours following administration of iron alone and following doses of iron with deferoxamine. There was no significant difference in peak iron concentration, time to peak iron concentration or area-under-the-curve between the two groups. Based on our results, equimolar doses of oral deferoxamine do not appear to decrease the absorption of low doses of oral iron in humans.

Absorption of iron after experimental overdose of chewable vitamins

Even though ingestion of chewable iron preparations is much more common, treatment recommendations for iron overdose are usually based on experience with nonchewable preparations. To determine the optimal time to measure serum iron concentrations, five volunteers were given chewable iron in 5 mg/kg and 10 mg/kg doses and their serum iron concentrations monitored. Peak levels occurred at 4.2 and 4.5 hours, respectively, after ingestion, and levels drawn at 3 hours were within 90% of the peak. Nausea and headache were experienced by all volunteers, and serum iron exceeded baseline total iron binding capacity in two subjects at the 10 mg/kg dose. In minor iron overdose resulting from the ingestion of chewable vitamins, serum iron concentrations measured between 3 and 7 hours (95% confidence level of peak concentrations) may be adequate in assessing the peak serum iron concentration.

Modafinil and Zolpidem Use by Emergency Medicine Residents

OBJECTIVES The objective was to assess the prevalence and patterns of modafinil and zolpidem use among emergency medicine (EM) residents and describe side effects resulting from use. METHODS A voluntary, anonymous survey was distributed in February 2006 to EM residents nationally in the context of the national American Board of Emergency Medicine in-training examination. Data regarding frequency and timing of modafinil and zolpidem use were collected, as well as demographic information, reasons for use, side effects, and perceived dependence. RESULTS A total of 133 of 134 residency programs distributed the surveys (99%). The response rate was 56% of the total number of EM residents who took the in-training examination (2,397/4,281). Past modafinil use was reported by 2.4% (57/2,372) of EM residents, with 66.7% (38/57) of those using modafinil having initiated their use during residency. Past zolpidem use was reported by 21.8% (516/2,367) of EM residents, with 15.3% (362/2,367) reporting use in the past year and 9.3% (221/2,367) in the past month. A total of 324 of 516 (62.8%) of zolpidem users initiated use during residency. Side effects were commonly reported by modafinil users (31.0%)-most frequent were palpitations, insomnia, agitation, and restlessness. Zolpidem users reported side effects (22.6%) including drowsiness, dizziness, headache, hallucinations, depression/mood lability, and amnesia. CONCLUSIONS Zolpidem use is common among EM residents, with most users initiating use during residency. Modafinil use is relatively uncommon, although most residents using have also initiated use during residency. Side effects are commonly reported for both of these agents, and long-term safety remains unclear.