Bruce D. Anderson

Acute, unintentional pediatric brodifacoum ingestions.

Background Brodifacoum is the major rodenticide used in the United States today. It is similar to warfarin but has more potent and prolonged effects. Large overdoses and chronic intoxication have been associated with significant coagulopathies and death. Currently, the management of acute unintentional ingestions by young children is controversial. Methods American Association of Poison Control Centers (AAPCC) data from 1993 to 1996 were retrospectively searched for acute, unintentional brodifacoum exposures without coingestions followed-up to a known outcome in children aged 6 years and younger. The cases were analyzed by management site, symptoms, therapy, and outcome. Cases coded as having clinical or laboratory evidence of coagulopathy were further evaluated for severity. Results Our study reviewed 10,762 cases that involved single, acute, unintentional ingestions of brodifacoum. All of the patients were followed-up to a known outcome as defined by AAPCC data collection standards. In this cohort, there were no deaths or major effects reported. Although 67 patients reported evidence of coagulopathy, no major effects or deaths were reported. Minor and moderate effects were reported in 38 and 54 children, respectively. Management occurred outside of a healthcare facility in 5404 (50.2 %) cases. Approximately half of all the children received some form of gastrointestinal decontamination. Decontamination had no effect on the distribution of outcomes. Adverse effects from decontamination therapy were reported in 42 patients. Conclusion Acute pediatric ingestions of brodifacoum rarely caused clinical effects and were not associated with life-threatening symptoms or death in young children. It seems reasonable that acute unintentional ingestions of small quantities of brodifacoum by young children can be adequately managed with home observation and parent education.

Analysis of sertraline-only overdoses

Sertraline is an antidepressant for which preliminary data suggest a low inherent toxicity. Previously reported case series have included coingestants or had small numbers of patients. This study was undertaken to determine the toxicity of overdoses of sertraline alone. A 2-year retrospective and 6-month prospective study was conducted at a regional poison center. There were 52 patients with a mean age of 19.3 +/- 13.8 years and a mean dose of 727 +/- 686 mg. There were no symptoms in 34 cases. Symptomatic patients experienced mild central nervous system, cardiovascular, and gastrointestinal effects. Two patients developed bradycardia which resolved without therapy. While all but 3 of 38 adolescents and adults were treated in a health care facility, 10 of 14 children were managed at home. Gastrointestinal decontamination was performed in 37 cases. No other specific therapy was required. Serious toxicity would not be expected following sertraline-only overdoses.

Diversion of 911 poisoning calls to a poison center

OBJECTIVE To determine the impact and safety of diverting poisoning calls from 911 to a regional poison center. METHODS A prospective six-month review was performed of all calls transferred from 911 dispatchers to a regional poison center for management. Recommendations for management and transport were made by the poison center using existing protocols. Patients were followed with telephone contact by poison center staff until symptoms resolved or until hospital discharge. Medical outcomes were categorized using the American Association of Poison Control Center guidelines for medical outcome. RESULTS A total of 262 cases were reviewed; four were excluded. The poison center was contacted prior to ambulance dispatch in 210 cases (81%). An ambulance was sent before the poison center was contacted 48 times (19%). The majority of patients originally calling 911 were managed at home (175/258; 68%). Patients experienced either no effect or minor effects in 254 cases (98%). Two patients developed moderate effects (0.8%), one developed a major effect (0.4%), and one died (0.04)%. No adverse effects or treatment delays resulted from diversion of calls to the poison center. CONCLUSIONS Appropriate poisoning and toxic exposure cases may be diverted safely from emergency medical services dispatch to a regional poison center for management, reducing unnecessary responses, with substantial cost savings.

Evaluation of quetiapine abuse and misuse reported to poison centers.

Objective:There are case reports of abuse of quetiapine, but no studies address quetiapine abuse or misuse. Most literature on the population that abuses quetiapine describes an older age group with previous substance abuse history, many of whom are in jail. The objective of this study was to evaluate national poison center data on misuse/abuse of quetiapine. Methods:A retrospective study of American Association of Poison Control Centers National Poison Data System data from 2005 to 2011 on single substance quetiapine exposures coded as intentional misuse or abuse and followed to known outcome was performed. Data were evaluated for age, toxicity, management sites, treatments, and medical outcomes. Results:There were 3116 cases meeting inclusion criteria; reason was misuse in 1948 cases and abuse in 1168 cases. The median age was 23 years. Misuse was reported most often in adults, whereas abuse occurred most frequently in adolescents. The male-to-female ratio was 1.7 for abuse and 1.0 for misuse. There were no deaths. Moderate or major toxicity occurred in 23.7% and 27.1% of misuse and abuse cases, respectively. Seventy-six percent were treated in the emergency department and/or received medical admission. Conclusions:Misuse was more common than abuse, except in adolescents for whom abuse was more frequent. Although outcomes were generally good, significant toxicity occurred in 25% of cases and more than 75% of the patients were treated in the emergency department and/or received medical admission. The consequences of nonmedical use of quetiapine are serious in some patients.

Interaction of tricyclic antidepressants with cholestyramine in vitro.

The adsorption of amitriptyline, desipramine, doxepin, imipramine, and nortriptyline onto cholestyramine was demonstrated in vitro with use of 1.2 mol/L HCl at 37 degrees C to simulate gastric fluid. Binding to cholestyramine was approximately 80% for each of the tricyclic antidepressants, and this was about the same degree of binding noted with a nonpharmaceutical, non-ionic resin widely used in the diagnostic toxicology laboratory (Amberlite XAD-2). In contrast, five other non-antidepressants (acetaminophen, chlordiazepoxide, procainamide, quinidine, and theophylline) showed only minimal binding to cholestyramine under these conditions. Activated charcoal completely bound all drugs studied. These findings suggest that cholestyramine should be used with caution in patients receiving tricyclic antidepressants. They also suggest that cholestyramine may be a potentially useful adjunctive therapy in treatment of overdose with the tricyclic antidepressants.

Potential for erroneous interpretation of poisoning outcomes due to changes in National Poison Data System reporting

Background/Objective. In 2006, the annual report of poison centers in the United States changed the method of reporting profiles for generic substance categories from all exposures to single-substance exposures only. The objective of this study is to describe the potential impact of this reporting change on longitudinal analysis of outcomes. Methods. Generic substance categories with data available for all years of the study were manually extracted from Table 22 of the National Poison Data System (NPDS) annual reports for 2002–2007. For each generic substance category, the following data were extracted for each of the 6 years: total number of substance mentions (2002–2005) or single-substance exposures (2006–2007), reason (unintentional or intentional), pediatric exposures (children age <6 years), and outcomes of major effect and death. Data were compared using descriptive analysis (Wilcoxon signed-rank test) and negative binomial regression. Results. There were 65 generic substance categories (30 drug categories and 35 nondrug categories) that had data in all study years. For drug categories the average annual number of reported deaths by substance category decreased by 80.8%, from 2,229 in year 2002–2005 to 428 after the 2006 reporting change (p < 0.0001). The average annual number of reported major outcomes by substance category dropped by 76.0% (p < 0.0001). The impact on nondrug categories was similar: the annual average number of deaths and major effects by substance category decreased by about 50% from 394 and 4,639 per year during 2002–2005 to 198 deaths (p < 0.0001) and 2,357 major effects (p ≤ 0.0001) during 2006–2007. After controlling for potential covariates, multivariate regression showed that there were significant decreases in average rates of reported deaths (61.7 and 35.9%) and major effects (36.3 and 11.2%) for drug categories and nondrug categories, respectively (p < 0.01 for all). Conclusions. Overall rates of major outcomes and deaths reported to poison control centers from 2002 to 2007 have remained constant. The new method of describing demographic data in Table 22 results in outcomes that are different from those reported in previous NPDS annual reports. Comparing NPDS generic substance outcome data before and after the reporting change in 2006 will yield inaccurate results if the change in reporting methodology is not taken into account.

Cholinergic Toxicity Resulting from Ocular Instillation of Echothiophate Iodide Eye Drops

A patient developed a severe cholinergic syndrome from the use of echothiophate iodide ophthalmic drops, presented with profound muscle weakness and was initially given the diagnosis of myasthenia gravis. Red blood cell and serum cholinesterase levels were severely depressed and symptoms resolved spontaneously following discontinuation of the eye drops.

Toxicity and clinical outcomes of paliperidone exposures reported to U.S. Poison Centers

Abstract Context. Paliperidone is an atypical antipsychotic that was approved in the U.S. in 2006, and is also available in Canada, Australia, New Zealand, Europe, and Asia. Information regarding paliperidone overdoses is limited to case reports. Serious toxicity has yet to be reported. Objective. To evaluate the toxicity of paliperidone exposures using a national poison center database. Methods. A retrospective, observational case series of single-substance paliperidone cases reported to the National Poison Data System from 2007 to 2012 was conducted. Cases were evaluated for demographics, reason for exposure, clinical effects, treatments, disposition, and coded medical outcomes. For cases with major effects the text fields in poison center charts were evaluated to verify accuracy of coded outcome. The relationship between dose and severity of medical outcome was analyzed for acute exposure cases. Results. There were 801 paliperidone cases that met inclusion criteria that included 592 persons of 13 years or greater, 67 children of 6–12 years, 140 children of less than 6 years, and 2 unknown ages. Most common reasons for exposure included: suicide attempt (39.6%), unintentional general (21.1%), therapeutic error (15.7%), and adverse drug reaction (11.9%). The most commonly observed clinical effects were drowsiness/lethargy (28.7%), tachycardia (23.3%), and dystonia (14.2%). Most patients were managed in the emergency department (40.3%) or were admitted to a health care facility (HCF) (42.7%). In 564 cases treated in a HCF, treatments included activated charcoal (25.7%), antihistamines (21.1%), and benzodiazepines (9.4%). Medical outcomes were no effect (35.0%), minor (30.8%), moderate (33.7%), and major effect (0.5%). There were no deaths. Of 491 acute exposures, dose was coded for 74.3% of exposures. There was a significant difference in the reported median dose between those with no effect (6 mg) and either minor effect (12 mg; p = 0.047) or moderate effect cases (12 mg; p = 0.020) in 91 children less than 6 years. Conclusions. The majority of patients experienced no or minor toxicity and were not admitted for medical care. Although a higher dose was associated with a more serious outcome in children less than 6 years, the data do not provide clear-cut triage guidelines.

Abuse and Intentional Misuse of Promethazine Reported to US Poison Centers: 2002 to 2012.

Objective:Promethazine abuse has been reported. The objective was to investigate promethazine abuse/misuse in the United States. Methods:An 11-year retrospective review was conducted of promethazine abuse and intentional misuse cases without co-ingestants in persons 10 years and older reported to the National Poison Data System. Data were stratified by product (promethazine-alone [PA] or co-formulation [PC]) and evaluated for demographics, toxicity, management sites, and outcomes. Results:There were 354 single product abuse or misuse exposures—95 PA and 259 PC. Over the 11-year timeframe, the annual exposure rate per 100,000 population doubled. Exposures were most prevalent among 10 to 19 years old and young adults (20s), accounting for 69.5% of PA and 57.5% of PC cases. Clinical effects due to PA included drowsiness (43.2%), tachycardia (7.4%), agitation (13.7%), confusion (13.7%), slurred speech (12.6%), hallucinations (7.4%), dizziness (7.4%), and hypertension (5.3%). Drowsiness (53.4%) and tachycardia (20.8%) were more frequent with PC. There were significant differences between PA and PC in management site (P = 0.0078). Management sites for PA and PC, respectively, were emergency department (37.9%, 55.6%), non–health care facility (33.7%, 14.7%), critical care unit (8.4%, 11.2%), non–critical care unit (7.4%, 7.3%), psychiatry (2.1%, 4.2%), and other/unknown (10.5%, 7.0%). Outcomes for PA and PC, respectively, were no effect (21.0%, 12.4%), minor (58.9%, 53.7%), moderate (17.9%, 32.0%), and major effects (2.1%, 1.9%). Conclusions:Promethazine-alone abuse/misuse most frequently resulted in minor outcomes, and less than 20% required medical admission. Abuse/misuse of PC resulted in a higher frequency of health care facility treatment and a trend toward more moderate outcomes. These differences are most likely attributed to the co-formulate.

Trends in types of calls managed by U.S. poison centers 2000–2015

Abstract Aim: The number of cases reported to poison centers has decreased since 2008 but there is evidence that the complexity of calls is increasing. Objectives: The objectives are to evaluate national poison center data for trends in reason and how these changes effect management site, medical outcomes, and poison center workload. Methods: Data regarding reason, age, management site, and medical outcome were extracted from annual reports of the National Poison Data System from 2000 to 2015. The proportion of cases by year were determined for unintentional and intentional exposures. Analysis of data from a single poison center from 2005 to 2015 compared the number of interactions between poison center staff and callers for unintentional versus intentional reasons. Results: Trend analyses found that from 2000 to 2015 the percent of unintentional cases decreased (from 85.9 to 78.4%, p < .0001) and the percent of intentional cases increased (from 11.3 to 17.6%, p < .0001). Age distribution changed with a decrease in children <13 years of age and increase in adolescents and adults. In these latter two age groups, the proportion due to intentional exposure increased while unintentional declined. The distribution of management sites changed over the 16-year period, with a decrease in non-HCF cases and significant increase in percent of cases treated in a HCF. The frequencies of moderate effect, major effect, and death were significantly higher for intentional exposures than for unintentional exposures. Analysis of data entry notes from a single center showed that the mean number of notes per unintentional case (1.61 ± 0.08) was significantly different from the mean number of notes per intentional case (9.23 ± 0.68) (p < .0001). Discussion: Poison centers are managing more intentional exposures and fewer unintentional exposures. Intentional exposures require more poison center staff expertise and time. Conclusion: Looking only at poison center total call volume may not be an adequate method to gauge productivity.