Toxicoepidemiology and predictors of death in 2,4-dinitrophenol (DNP) toxicity.

INTRODUCTION: 2,4-Dinitrophenol (DNP) is a highly toxic industrial chemical that is sometimes misused to reduce body fat. Toxicity following ingestion of DNP has recently become more common in the United Kingdom. This research was performed to document the frequency of DNP toxicity as reported to poisons centres in the United States (US) and United Kingdom (UK) and to identify the clinical features associated with fatality. METHODS: Calls to UK and US poisons centres involving systemic exposure to DNP were extracted for the 12 calendar years 2007-2018. These were analysed using univariate and multivariate statistical techniques. RESULTS: There were 204 cases (n = 86, US; n = 118, UK) of systemic DNP exposure identified, of which 86% were under the age of 40 and 71% were males. Over the study period the incidence of reported DNP toxicity was higher in the United Kingdom than the United States (1.78 vs. 0.26 cases per million population) and annual case numbers have increased in both countries since 2011. Case fatality was high and did not differ significantly between countries (US 11.6%; 95% CI: 6.4-20.1%: UK 16.9%; 95% CI: 11.3-24.7%; X2(1) = 1.12, p = 0.29). Univariate analysis demonstrated significant associations between risk of death and the presence of hypoglycaemia (OR = 17.1, 95% CI 1.7-174.3), hypertonia (OR = 12.9, 95% CI 3.5-47.6), acidosis (OR = 12.5, 95% CI 4.8-32.9), raised lactate (OR = 8.3, 95% CI 2.4-28.4), hyperpyrexia (OR = 6.5, 95% CI 2.8-15.2), tachycardia (OR = 6.4, 95% CI 2.5-16.4), agitation or confusion (OR = 6.0, 95% CI 2.6-13.7), hypertension (OR = 5.6, 95% CI 1.9-16.4) and tachypnoea/dyspnoea (OR = 2.8, 95% CI 1.2-6.1). After backwards stepwise logistic regression, the following were retained as significant independent predictors of mortality: acidosis (OR = 5.4, 95% CI: 1.8 - 16.5), tachycardia (OR = 3.6, 95% CI: 1.2 - 11.0), agitation/confusion (OR = 3.4, 95% CI: 1.2 - 9.7) and hyperpyrexia (OR = 2.8, 95% CI: 1.0 - 7.4). DISCUSSION: DNP toxicity is uncommonly reported to poisons centres but has recently become more frequent in the United States and United Kingdom. Tachycardia, hyperpyrexia, acidosis, and agitation/confusion are independent risk factors for mortality and their presence should prompt rapid escalation to an intensive care environment for aggressive supportive treatment and monitoring.

Standard Information Models for Representing Adverse Sensitivity Information in Clinical Documents.

BACKGROUND: Adverse sensitivity (e.g., allergy and intolerance) information is a critical component of any electronic health record system. While several standards exist for structured entry of adverse sensitivity information, many clinicians record this data as free text. OBJECTIVES: This study aimed to 1) identify and compare the existing common adverse sensitivity information models, and 2) to evaluate the coverage of the adverse sensitivity information models for representing allergy information on a subset of inpatient and outpatient adverse sensitivity clinical notes. METHODS: We compared four common adverse sensitivity information models: Health Level 7 Allergy and Intolerance Domain Analysis Model, HL7-DAM; the Fast Healthcare Interoperability Resources, FHIR; the Consolidated Continuity of Care Document, C-CDA; and OpenEHR, and evaluated their coverage on a corpus of inpatient and outpatient notes (n = 120). RESULTS: We found that allergy specialists' notes had the highest frequency of adverse sensitivity attributes per note, whereas emergency department notes had the fewest attributes. Overall, the models had many similarities in the central attributes which covered between 75% and 95% of adverse sensitivity information contained within the notes. However, representations of some attributes (especially the value-sets) were not well aligned between the models, which is likely to present an obstacle for achieving data interoperability. Also, adverse sensitivity exceptions were not well represented among the information models. CONCLUSIONS: Although we found that common adverse sensitivity models cover a significant portion of relevant information in the clinical notes, our results highlight areas needed to be reconciled between the standards for data interoperability.

Mortality and drug exposure in a 5-year cohort of patients with chronic liver disease.

BACKGROUND: Chronic liver diseases are common in the general population. Drug treatment in this group may be challenging, as many drugs are hepatically metabolised and hepatotoxic. OBJECTIVES: We aimed to assess the mortality of patients with chronic liver disease according to specific drug exposures and the three laboratory parameters creatinine, bilirubin and International Normalised Ratio (INR). METHODS: We conducted a multicentre, 5-year retrospective cohort study in two tertiary university referral hospitals and a secondary referral hospital, using a research database to evaluate the crude and adjusted mortality. RESULTS: Of 1159362 individual patients 1.7% (n = 20158) had chronic liver disease and in this group 36.8% had unspecified chronic non-alcoholic liver disease, 30.1% chronic hepatitis C and 11.9% cirrhosis of the liver. 8.4% of patients presented a diagnosis associated with alcohol. The 4-year survival rates were significantly higher in the group with the most normal laboratory values (94.3%) versus 34.5% in the group with elevated parameters (p <0.001). Overall, drug exposure was not associated with higher mortality; in adjusted multivariate analysis the hazard ratio for anti-cancer drugs was 2.69 (95% CI 1.32-5.46). Of individual drugs, mortality hazard ratios for amiodarone, morphine oral, acetazolamide, sirolimus and lamivudine were 2.46 (95% CI 1.68-3.61), 2.26 (95% CI 1.78-2.86), 2.10 (95% CI 1.19-3.70), 1.81 (95% CI 1.02-3.21) and 1.72 (95% CI 1.17-2.53) respectively. CONCLUSIONS: Drug exposure in general was not associated with higher mortality except for a few categories. Mortality in patients with chronic liver disease was high and is associated with simple laboratory values.

Guided medication dosing for inpatients with renal insufficiency.

CONTEXT: Usual drug-prescribing practices may not consider the effects of renal insufficiency on the disposition of certain drugs. Decision aids may help optimize prescribing behavior and reduce medical error. OBJECTIVE: To determine if a system application for adjusting drug dose and frequency in patients with renal insufficiency, when merged with a computerized order entry system, improves drug prescribing and patient outcomes. DESIGN, SETTING, AND PATIENTS: Four consecutive 2-month intervals consisting of control (usual computerized order entry) alternating with intervention (computerized order entry plus decision support system), conducted in September 1997-April 1998 with outcomes assessed among a consecutive sample of 17 828 adults admitted to an urban tertiary care teaching hospital. INTERVENTION: Real-time computerized decision support system for prescribing drugs in patients with renal insufficiency. During intervention periods, the adjusted dose list, default dose amount, and default frequency were displayed to the order-entry user and a notation was provided that adjustments had been made based on renal insufficiency. During control periods, these recommended adjustments were not revealed to the order-entry user, and the unadjusted parameters were displayed. MAIN OUTCOME MEASURES: Rates of appropriate prescription by dose and frequency, length of stay, hospital and pharmacy costs, and changes in renal function, compared among patients with renal insufficiency who were hospitalized during the intervention vs control periods. RESULTS: A total of 7490 patients were found to have some degree of renal insufficiency. In this group, 97 151 orders were written on renally cleared or nephrotoxic medications, of which 14 440 (15%) had at least 1 dosing parameter modified by the computer based on renal function. The fraction of prescriptions deemed appropriate during the intervention vs control periods by dose was 67% vs 54% (P<.001) and by frequency was 59% vs 35% (P<.001). Mean (SD) length of stay was 4.3 (4.5) days vs 4.5 (4.8) days in the intervention vs control periods, respectively (P =.009). There were no significant differences in estimated hospital and pharmacy costs or in the proportion of patients who experienced a decline in renal function during hospitalization. CONCLUSIONS: Guided medication dosing for inpatients with renal insufficiency appears to result in improved dose and frequency choices. This intervention demonstrates a way in which computer-based decision support systems can improve care.

Correlates of acute renal failure in patients receiving parenteral amphotericin B.

BACKGROUND: While parenteral amphotericin B is an effective therapy for serious fungal infections, it frequently causes acute renal failure (ARF). This study identified correlates of ARF in amphotericin B therapy and used them to develop clinical prediction rules. METHODS: All 643 inpatients receiving parenteral amphotericin B therapy at one tertiary care hospital were included. Data regarding correlates were obtained both electronically and from manual chart review in a subsample of 231 patients. ARF was defined as a 50% increase in the baseline creatinine with a peak > or =2.0 mg/dL. RESULTS: Among 643 episodes, ARF developed in 175 (27%). In the larger group, the only independent correlate of ARF was male gender (OR = 2.2, 95% CI, 1.5 to 3.3). In the subsample (N = 231), independent correlates of ARF were maximum daily amphotericin dosage, location at the time of initiation of amphotericin therapy, and concomitant use of cyclosporine. These data were used to develop two clinical prediction rules. A rule using only data available at initiation of therapy stratified patients into groups with probability of ARF ranging from 15 to 54%, while a rule including data available during therapy (maximum daily dose) stratified patients into groups with probability of ARF ranging from 4 to 80%. CONCLUSIONS: Acute renal failure occurred in a quarter of the patients. Correlates of ARF at the beginning and during the course of amphotericin therapy were identified and then combined to allow stratification according to ARF risk. These data also provide evidence for guidelines for the selection of patients for alternative therapies.

Mortality and costs of acute renal failure associated with amphotericin B therapy.

To assess the mortality and resource utilization that results from acute renal failure associated with amphotericin B therapy, 707 adult admissions in which parenteral amphotericin B therapy was given were studied at a tertiary-care hospital. Main outcome measures were mortality, length of stay, and costs; we controlled for potential confounders, including age, sex, insurance status, baseline creatinine level, length of stay before beginning amphotericin B therapy, and severity of illness. Among 707 admissions, there were 212 episodes (30%) of acute renal failure. When renal failure developed, the mortality rate was much higher: 54% versus 16% (adjusted odds of death, 6.6). When acute renal failure occurred, the mean adjusted increase in length of stay was 8.2 days, and the adjusted total cost was $29,823. Although residual confounding exists despite adjustment, the increases in resource utilization that we found are large and the associated mortality is high when acute renal failure occurs following amphotericin B therapy.

Identifying drug safety issues: from research to practice.

PURPOSE: Adverse drug events (ADEs), or injuries due to drugs, are common and often preventable. However, identifying ADEs, potential ADEs, and medication errors can be a major challenge. In this review, we describe methodologies that have been used to identify these events and give strategies for identification in non-study settings. RESULTS: Methods such as voluntary reporting, chart review, and computerized monitoring for events have been most commonly used in studies of ADEs in inpatients. However, voluntary reporting, the method most hospitals currently use, has a very low yield of events. Chart review is much more sensitive but the costs are prohibitive. Computerized monitoring for ADEs (using rules or triggers) is a high yield and relatively inexpensive strategy that should be adopted by organizations. A limitation of this strategy, however, is that it identifies few medication errors and potential ADEs, which are also important. These can be captured through pharmacy logs, chart review, and direct observation. Once events have been identified, they can be classified by type of event, severity, and preventability. In non-study settings, the most practical method for identifying ADEs is computerized monitoring, and for identifying prescribing errors it is pharmacy logs of interventions. Once problems are found, a structure (either individual or committee) must be in place to classify them, identify opportunities for improvement, and carry out the necessary changes. CONCLUSIONS: Health care organizations have the technology to significantly improve their detection of ADEs, medication errors, and potential ADEs. Identification and subsequent classification of events is crucial for quality efforts to improve patient safety.

Felbamate overdose complicated by massive crystalluria and acute renal failure.

CASE REPORT: We report a 20-year-old woman who developed altered mental status, massive crystalluria, and acute renal failure following an intentional overdose of felbamate and sodium valproate. Peak plasma concentrations of felbamate and sodium valproate were 200 microg/mL and 470 microg/mL, respectively. Macroscopic urinary crystals formed approximately 18 hours after ingestion and were identified by gas chromatography as containing felbamate. Renal ultrasound revealed unilateral hydronephrosis. Following parenteral hydration, the crystalluria and acute renal failure resolved and the patient recovered. The frequency and significance of crystalluria in felbamate intoxication is unknown.

An information system to promote intravenous-to-oral medication conversion.

Many inpatients remain on expensive intravenous medications, even after they become able to take bioequivalent oral alternatives. We developed a computer intervention to identify such patients and to deliver alerts suggesting a switch to the oral medication. In the first phase of the project, alerts were delivered to pharmacists. The Brigham Integrated Computer System (BICS) was used to produce a daily report of patients receiving any of six targeted intravenous medications, who also had orders for an oral diet or other scheduled oral medications. Staff pharmacists screened the report and suggested IV to PO conversion in appropriate cases to the patient's nurses and/or physicians. Feedback was documented in the BICS system. Analysis of the pilot study showed that in 31.7% of cases, physicians agreed to change (or had just changed) the patient's medication from IV to PO. Further analysis of pilot (Phase I) data was performed against a variety of parameters in order to increase the fraction of alerts deemed appropriate for conversion. These more specific alerts can be sent directly to physicians.

Effect of computerized physician order entry and a team intervention on prevention of serious medication errors.

CONTEXT: Adverse drug events (ADEs) are a significant and costly cause of injury during hospitalization. OBJECTIVES: To evaluate the efficacy of 2 interventions for preventing nonintercepted serious medication errors, defined as those that either resulted in or had potential to result in an ADE and were not intercepted before reaching the patient. DESIGN: Before-after comparison between phase 1 (baseline) and phase 2 (after intervention was implemented) and, within phase 2, a randomized comparison between physician computer order entry (POE) and the combination of POE plus a team intervention. SETTING: Large tertiary care hospital. PARTICIPANTS: For the comparison of phase 1 and 2, all patients admitted to a stratified random sample of 6 medical and surgical units in a tertiary care hospital over a 6-month period, and for the randomized comparison during phase 2, all patients admitted to the same units and 2 randomly selected additional units over a subsequent 9-month period. INTERVENTIONS: A physician computer order entry system (POE) for all units and a team-based intervention that included changing the role of pharmacists, implemented for half the units. MAIN OUTCOME MEASURE: Nonintercepted serious medication errors. RESULTS: Comparing identical units between phases 1 and 2, nonintercepted serious medication errors decreased 55%, from 10.7 events per 1000 patient-days to 4.86 events per 1000 (P=.01). The decline occurred for all stages of the medication-use process. Preventable ADEs declined 17% from 4.69 to 3.88 (P=.37), while nonintercepted potential ADEs declined 84% from 5.99 to 0.98 per 1000 patient-days (P=.002). When POE-only was compared with the POE plus team intervention combined, the team intervention conferred no additional benefit over POE. CONCLUSIONS: Physician computer order entry decreased the rate of nonintercepted serious medication errors by more than half, although this decrease was larger for potential ADEs than for errors that actually resulted in an ADE.

Identifying adverse drug events: development of a computer-based monitor and comparison with chart review and stimulated voluntary report.

BACKGROUND: Adverse drug events (ADEs) are both common and costly. Most hospitals identify ADEs using spontaneous reporting, but this approach lacks sensitivity; chart review identifies more events but is expensive. Computer-based approaches to ADE identification appear promising, but they have not been directly compared with chart review and they are not widely used. OBJECTIVES: To develop a computer-based ADE monitor, and to compare the rate and type of ADEs found with the monitor with those discovered by chart review and by stimulated voluntary report. DESIGN: Prospective cohort study in one tertiary-care hospital. PARTICIPANTS: All patients admitted to nine medical and surgical units in a tertiary-care hospital over an eight-month period. MAIN OUTCOME MEASURE: Adverse drug events identified by the computer-based monitor, by chart review, and by stimulated voluntary report. METHODS: A computer-based monitoring program identified alerts, which were situations suggesting that an ADE might be present (e.g., an order for an antidote such as naloxone). A trained reviewer then examined patients' hospital records to determine whether an ADE had occurred. The results of the computer-based monitoring strategy were compared with two other ADE detection strategies: intensive chart review and stimulated voluntary report by nurses and pharmacists. The monitor and the chart review strategies were independent, and the reviewers were blinded. RESULTS: The computer monitoring strategy identified 2,620 alerts, of which 275 were determined to be ADEs. The chart review found 398 ADEs, whereas voluntary report detected 23. Of the 617 ADEs detected by at least one method, 76 ADEs were detected by both computer monitor and chart review. The computer monitor identified 45 percent; chart review, 65 percent; and voluntary report, 4 percent. The ADEs identified by computer monitor were more likely to be classified as "severe" than were those identified by chart review (51 versus 42 percent, p = .04). The positive predictive value of computer-generated alerts was 16 percent during the first eight weeks of the study; rule modifications increased this to 23 percent in the final eight weeks. The computer strategy required 11 person-hours per week to execute, whereas chart review required 55 person-hours per week and voluntary report strategy required 5. CONCLUSIONS: The computer-based monitor identified fewer ADEs than did chart review but many more ADEs than did stimulated voluntary report. The overlap among the ADEs identified using different methods was small, suggesting that the incidence of ADEs may be higher than previously reported and that different detection methods capture different events. The computer-based monitoring system represents an efficient approach for measuring ADE frequency and gauging the effectiveness of ADE prevention programs.

Hemolytic anemia following a presumptive brown recluse spider bite.

This case report describes a systemic reaction occurring in a 12-year-old female following presumed envenomation by a brown recluse spider (Loxosceles reclusa). The systemic reaction included self-limited hemolysis necessitating blood transfusion. The clinical course and management are described and compared with those of previously reported cases of systemic loxoscelism.

Topics in clinical pharmacology: flumazenil, a benzodiazepine antagonist.

Flumazenil is a central antagonist of the sedative effects of benzodiazepines. It has been used to reverse benzodiazepine effects in conscious sedation, general anesthesia, and overdose with restoration of alertness and psychomotor function within minutes of administration. Seizures have followed the use of flumazenil. Overdose patients who have co-ingested cyclic antidepressants are especially at risk for this complication. Flumazenil is administered intravenously in small, incremental doses.

Metal fume fever--a review.

Metal fume fever (MFF) is an acute industrial disease caused by the inhalation of a variety of heavy metal oxides. MFF occurs most commonly during welding operations, particularly those involving zinc oxide. The illness is of short duration and produces symptoms of cough, fever, chills, malaise, and myalgias. Its etiology is uncertain, and its diagnosis is difficult because symptoms resemble a number of pulmonary illnesses. Supportive treatment, with bed rest, analgesics, and fever control is used for symptomatic relief. Emergency medicine physicians must differentiate the clinical picture from other common respiratory illnesses. The mainstay of therapy for MFF consists of recognizing the disease and preventing subsequent exposure to harmful metals.

Mesenteroaxial gastric volvulus in children.

We have presented a case of mesenteroaxial volvulus in a 12-year-old girl. Since this entity is rare in children, one must be especially alert to its possibility for early diagnosis and treatment of this potential catastrophe.

Childhood sigmoid volvulus.

A 14-year-old boy presented to the emergency department with abdominal pain. Flat and upright abdominal films and a barium enema revealed the classic findings of sigmoid volvulus. Sigmoidoscopy allowed a soft rubber tube to be passed beyond the obstruction with immediate relief of pain. The patient subsequently underwent a descending sigmoid colectomy. Sigmoid volvulus is a rare entity in childhood. Case discussion and review of the literature is presented.