Research Forum Abstracts

328 Clinical Characteristics of NeonicotinoidInsecticides Poisioning

Kim J/Seoul St. Mary’s Hospital in Korea, Seoul, Korea, Republic of

Study Objectives: Neonicotinoid insecticides are widely used as they have beenproven by experimental studies to be low toxicity to mammals including humans. Asthe use of neonicotioids increases, neonicotinoids poisioning patients is alsoincreasing. We therefore conducted a study to investigate the clinical manifestationsof neonicotinids poisioning.

Methods: We retrospectively analyzed neonicotinids ingestion patients whovisited the emergency department of Seoul St. Mary’s hospital in Korea from March2002 to February 2010.

Results: A total number of 23 patients were analyzed. 18 patients, complaining ofmild gastrointestinal symptoms such as nausea and vomiting, showed mild toxicity with apoisoning severity score of 1. 4 patients showed fatal conditions such as shock andmutiorgan failure with a poisoning severity of 3 and one died. In these fatal cases, thepatients were elderly patients who arrived at the emergency department after 5-6 hours ofingestion. Hence, gastrointestinal decontamination had been delayed and the patientsdeveloped respiratory failure and renal fauilure. Decreased renal excretion of neonicotinidmetabolite led to severe toxicity which was improved only after hemodialysis.

Conclusion: Neonicotinoids intoxication patients who showed mild toxicityusually improved after symptomatic treatment. However, when patients show signs ofdeteriorating renal function, we need to take particular attention and consideremergency hemodialysis as these patients may progress to severe toxicity.

329 Safety and Cost-Effectiveness of Establishing aProtocol for Utilization of CroFab™ at an AcademicMedical Center

Weant KA, Bowers RC, Reed JL, Braun CA, Dodd DM, Baker SN/University ofKentucky Chandler Medical Center, Lexington, KY

Background: CroFab™ has been approved for use since December 2000. Overthe last decade, much research has been directed towards evaluating its safety,effectiveness, and cost to benefit ratio. While it has been shown to have a relativelygood safety profile and to be effective in treating a range of patient populations, thereremains a significant amount of disagreement due to limited data over how to utilizeit in a cost effective yet safe manner.

Objective: Our institution experienced excessive usage as well as wastage ofCroFab™ product due to differing provider utilization practices. It was felt thatestablishing a medical center wide treatment protocol for crotalid envenomationwould contain the cost of usage and limit wastage of product. A multidisciplinaryteam from the department of emergency medicine and the department of pharmacywas convened to develop the protocol based upon manufacturer recommendationsand review of the literature. After three years of implementation, we evaluated theeffectiveness and safety of the protocol. The primary objective of this study was todetermine if a cost savings existed post-protocol both in terms of actual CroFab™used as well as hospital length of stay. The secondary objective was to determine if useof the protocol provided an equivalent patient safety record compared to pre-protocolincluding number of fasciotomies, deaths, overall length of stay, number of ICUadmissions and adverse reactions.

Methods: An IRB-approved retrospective chart review by 5 trained extractorsutilizing a standardized data collection tool.

Setting: An academic medical center seeing 47,000 patients per year.Participants: All patients presenting to the hospital with a diagnosis of snake

envenomation from 2003-2009.Data collected: Charts were evaluated in two groups: pre-protocol from 2003-

June 2006 and post-protocol July 2006-2009. Data collected from each chartincluded: total number of CroFab™ vials used, hospital length of stay, ICUadmission days, as well as occurrence of fasciotomy, death, and adverse reaction.

Results: A total of 75 patients met criteria for inclusion into this study. Followingimplementation of the protocol, it was utilized in 39% of eligible patients. In thosepatients in which the protocol was followed there were significantly fewer vials used(2.375 versus 5.625; p�0.005). This use was lower with no significant difference indeaths, adverse reactions or progression to fasciotomy.

Although there was no significant difference in the severity of envenomation betweenthese two groups (p�0.634), there was noted a significantly lower hospital length of stayin the group compliant with the protocol (1.8 versus 2.632 days; p�0.035).

Conclusion: Compliance with a multidisciplinary snake envenomation protocol

resulted in approximately three fewer vials used per patient and a lower hospital

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length of stay without a corresponding increase in adverse effects or envenomationprogression. This decrease in usage correlates to a medication cost savings ofapproximately $3,000 per patient as well as the reduced cost associated with a shorterlength of stay. In addition, this results in a reduced exposure of the patient to anunnecessary medication and its possible side effects.

330 QTc Prolongation In Emergency DepartmentPatients: Disposition Decision and Administrationof QTc Prolonging Medications

House SL, Vitkovitsky I, Kim A, Treaster M, Burkett J, Halcomb SE/WashingtonUniversity in St. Louis, St. Louis, MO

Study Objectives: QTc prolongation is associated with significant morbidity andmortality including fatal arrhythmias such as torsades de pointes (TdP). Recognitionof QTc prolongation in the emergency department (ED) is important as it may affectdisposition as well as alter medication choice. Very few studies have investigated QTcprolongation in ED patients. The purpose of this study is to determine theassociation of QTc prolongation in ED patients with disposition and theadministration of QTc prolonging medications.

Methods: This study was a retrospective review of ED patients who received anECG for any reason during June - August 2009 at a large volume, tertiary care center.Inclusion criteria were patients with a computer-generated QTc � 460 ms. Exclusioncriteria included patients with an ECG showing bradycardia (HR � 60 bpm),tachycardia (HR � 100 bpm), QRS � 120 ms, non-sinus or paced rhythm, orpatients who left without being seen. ED visit records were reviewed for dispositionand medications administered in the ED. QTc prolonging medications were definedas those listed by the Arizona Center for Education and Research on Therapeutics(AzCERT) and were classified as Class 1 (accepted to cause TdP), Class 2 (prolongQTc and have been reported to cause TdP), and Class 3 (prolong QTc and causeTdP under certain circumstances) as defined by AzCERT.

Results: During this 3-month period, 6870 patients received ECGs. 1403patients had a QTc � 460 ms (20%, 95%CI 19-21%). 766 patients were excluded,leaving 637 eligible patients. Patients were divided into groups based on their QTc.349 patients (55%, 95%CI 51-59%) had a QTc 460-479 ms, 162 patients (25%,95%CI 22-29%) had a QTc 480-499 ms, and 126 patients (20%, 95%CI 17-23%)had a QTc � 500 ms. 162 patients received QTc prolonging medications (25%,95%CI 22-29%) in the ED. There was a statistically significant association betweenthe degree of QTc prolongation and the receipt of QTc prolonging medications(24% for QTc 460-479 ms, 21% for QTc 480-499 ms, and 34% for QTc - 500 ms,p�0.05). Of the patients which received QTc prolonging medications, 20 receivedClass 1 (12%, 95%CI 7-17%), 112 received Class 2 (69%, 95%CI 62-76%), and 49received Class 3 (30%, 95%CI 23-37%). 14% of the patients received multiple QTcprolonging medications in the ED (95%CI 8-19%). There was a statisticallysignificant association between longer QTc interval prolongation and receivingmultiple QTc prolonging medications (p�0.05). ED patient dispositions were 216discharged (34%, 95%CI 30-38%), 73 admitted without telemetry (12%, 95%CI9-14%), and 335 admitted with telemetry (53%, 95%CI 49-56%). There was nostatistically significant association between QTc interval group and the decision todischarge or admit without telemetry. There was a significant association betweenincreased QTc interval and admission with telemetry (49% for QTc 460-479 ms,54% for QTc 480-499 ms, and 60% for QTc � 500 ms, p�0.05).

Conclusion: The administration of QTc prolonging medications is common inED patients with prolonged QTc. Patients with the most prolonged QTc were athighest risk of receiving one or more QTc prolonging medications in the ED. Manypatients were discharged from the ED with prolonged QTc, even in patients withQTc � 500 ms. Careful attention should be paid to QTc interval when determiningmedication administration and disposition decision.

331 Negative Predictive Value of Serum Measurementof Acetaminophen Obtained Less Than 4 HoursAfter Oral Overdose In Determining Need forAntidotal Therapy

Tupper M, Keyes DC, Fowler J, Hornacek B, Singal B/University of Michigan/Saint Joseph Mercy Hospital, Ann Arbor, MI; Saint Joseph Mercy Health System,Ann Arbor, MI

Study Objectives: After an overdose, a serum level of acetaminophen obtained in

the emergency department (ED) is routinely plotted on a treatment nomogram and a

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Research Forum Abstracts

decision is made with respect to administration of antidote and admission to thehospital. In many EDs, the first level is often obtained in less than 4 hours afteringestion, soon after the patient’s arrival. However, the current acetaminophentreatment nomogram is not useable prior to 4 hours after ingestion. If a level wasobtained within the first 4 hours, an additional post-4-hour-level is still required inorder to make use of the nomogram. This causes delay and adds expense to thepatient’s care. It would be helpful to know whether a negative result obtained � 4hours after overdose would be sufficient to determine that the patient does notrequire the use of therapy with n-acetyl cysteine (NAC), and subsequent admission.

The current study proposes to determine whether a negative quantitative serumtest for acetaminophen, obtained within 4 hours of ingestion, can successfully identifythose patients who can be dispositioned without NAC according to the nomogram.

Methods: This study is a retrospective review of the records of 254 patients whowere seen within 4 hours following an overdose in a 44-bed, level II trauma ED,serving a 537-bed teaching hospital, from 2001-2009. Exclusion criteria included : 1)inaccurate history of overdose, or where the time of ingestion (TOI) was notdescribed with certainty within an interval of � 1 hour, 2) not a single ingestion(time), and 3) absence of levels at either �4 hrs or � 4 hrs. Demographics, serumacetaminophen levels and other clinical characteristics were recorded. A value of 100mcg/mL or greater was used to define a positive �4 hour level for the study. A k-statistic was calculated among abstracters and double data entry was used to ensurethe quality of the database. IRB approval was obtained for all parts of the study.

Results: A total of 92 patients were eligible for inclusion. Of these, 63% were female,73% White , 21% African-American, and 6% others. The average age was 28 years, witha range of 1 to 75. 162 patients were excluded based on 1) inadequate history: 100(39.4%) 2) for not being a single ingestion: 81 (31.9%), and for not having levels both�4 hrs and �4 hrs: 154 (60.6%). Of the 92 eligible patients, 69 (75% of of total sample)had a true negative, defined as � 100 mcg/mL at time � 4 hrs, and an acetaminophenlevel below the U.S. nomogram treatment line at � 4 hours, and there were no falsenegatives (NPV of 1, 95% CI .93 to 1, sensitivity of 1 (95% CI .46 to 1) and specificity of.79 (95% CI .69 to .86)). There were no acetaminophen levels reported for � 30 minutesfollowing the TOI, and 88% of levels were obtained � 1 hour from the TOI.

Conclusion: This retrospective study found that an early acetaminophen serumlevel of � 100 mcg/mL obtained between 30 minutes and 4 hours after overdoseeffectively defined which patients did not require a repeat level or antidotal treatmentin this patient population. A prospective trial is underway to further define this issue.

332 Rising Salicylate Concentrations: Is It Necessaryto Follow Serial Levels?

Grandey K, Lu JJ, Bryant SM/Cook County Hospital (Stroger), Chicago, IL

Study Objectives: Patients with salicylate (ASA) poisoning will often require serialconcentrations to determine ongoing absorption and to monitor toxicity. Initial ASAconcentrations are sometimes erroneously interpreted to be “peak” levels.Additionally, levels that are undetectable or within the therapeutic range are notalways repeated due to the belief that a significant ASA ingestion has been excluded orthat ASA poisoning is unlikely to become clinically relevant. Our objective was toevaluate rising ASA concentrations in patients after a reported ASA ingestion.

Methods: We reviewed all Illinois Poison Center (IPC) cases for the period July 1,2004 through December 31, 2009 to identify patients with ASA concentrations � 30mg/dL at any point during their hospitalization. These cases were then divided into threegroups with initial ASA levels of 1) � 30 mg/dL; 2) 11-29 mg/dL; and 3) � 10 mg/dL.Only those cases with a subsequent rising ASA level were included. Number of cases withlevels rising to 60 mg/dL or greater, number of patients who were hemodialyzed (HD),and number of patients who died from each group were also recorded.

Results: There were 140 total cases with rising ASA levels. 74/140 (53%) cases withinitial ASA levels �30 mg/dL demonstrated subsequent levels that continued to rise, with21/74 (28%) rising to � 60 mg/dL. Thirty-seven percent (52/140) with initial ASA levels11-29 mg/dL had levels rising to �30 mg/dL while 3/52 (0.6%) rose to greater than 60mg/dL. Finally, there were 14/140 (10%) cases where the initial level was reported tobe � 10 mg/dL but eventually rose to �30 mg/dL. Interestingly, one patient with twoinitial “negative” ASA levels developed tinnitus and vomiting after being transferred to thepsychiatric ward and was found to have an ASA level of 54.8 mg/dL. Additionally, in thisfinal group, 2/14 cases (14%) actually revealed ASA levels that rose to greater than 60mg/dL. HD was performed in both of these cases. One of these patients presented with aninitial ASA level reported as � 4 mg/dL but was followed by a second level of 99.1 mg/dL. The second patient had an initial level recorded as 1.5 mg/dL which rose to 100 mg/dL. A post-HD level was 67 mg/dL, however the concentration rose again to 123 mg/dL.

The patient eventually was intubated and died shortly thereafter.

S108 Annals of Emergency Medicine

Conclusion: Salicylate metabolism switches from first-order kinetics to zero-orderkinetics at concentrations �30 mg/dL, with implications of delayed clearance and toxicityin overdose conditions. Furthermore, salicylate absorption, because of various reasonsincluding pylorospasm, coingestants, and intestinal bezoars, can be very erratic. For thesereasons, the time to rise and the actual amount of rise in ASA concentrations can be veryunpredictable. Most notably, we demonstrate here that initial levels reported astherapeutic or negligible can result in significant elevation necessitating intervention (eg,HD, urinary alkalinization). In two of the cases with initial ASA levels � 10 mg/dL, HDwas required while one patient ultimately was intubated and subsequently died. Thesedata suggest that any detectable ASA concentration should be repeated until clearlydecreasing and, in cases where an ASA ingestion is reported but the level is negative, thephysician should be aware of the possibility of delayed absorption.

333 Direct Comparison of 20-Hour IV N-acetylcysteine,36-Hour By Mouth N-acetylcysteine, and 72-Hour ByMouth N-acetylcysteine for Acute AcetaminophenPoisoning

Williamson K, Mycyk M, Wahl M/Northwestern Memorial Hospital, Chicago, IL;Illinois Poison Center, Toxikon Consortium, Chicago, IL

Study Objectives: Since the FDA approved IV N-acetylcysteine (NAC) for thetreatment of acetaminophen (APAP) poisoning in 2004, several cases of failure of that20h protocol have been published. While prior studies independently established theefficacy of the 20hIV and the 72hPO NAC protocols, no study has directly comparedthe two during the same time period or in the same region. The purpose of this studywas to determine if treatment with 20hIV NAC results in worse clinical outcomesthan treatment with the longer 36hPO or 72hPO NAC protocols in cases of acuteAPAP poisoning treated within 8h of overdose.

Methods: We performed a retrospective analysis of consecutive APAP poisoning casesmanaged by a regional poison center with an annual call volume �100,000 cases between1/1/2002 and 12/31/2007. All clinical data were prospectively entered in real time into astructured database. Variables and outcomes were determined a priori and data abstractionwas performed in a systematic manner according to the guidelines of Gilbert. Includedwere all patients treated for acute APAP overdose within 8h of ingestion who completedthe 20hIV, 36hPO, or 72hPO NAC protocol. Excluded were cases where treatment wasinitiated �8h after overdose, if duration of treatment did not comply with themanufacturer’s guidelines, if treatment changed between IV and PO routes, or if clinicaloutcome data were incomplete. The primary outcome was survival, death, or transplant.Since prognosis in APAP poisoning is determined by clinical outcomes rather than degreeof transaminase elevation, secondary outcomes in this study were hepatic encephalopathy,abnormal Cr, elevated INR, or abnormal pH as defined by King’s College.

Results: Out of 4642 APAP-cases, 795 met inclusion criteria: within 8 hours ofoverdose 213 received 20hIV NAC , 213 received 36hPO NAC, and 369 received72hPO NAC. In the 20hIV group mean age was 25 years, mean 4h APAP level was178mcg/mL, and 44(21%) co-ingested gut-slowing diphenhydramine; in the 36hPOgroup mean age was 26, mean 4hAPAP level was 165, and 20(9%) co-ingesteddiphenhydramine; in the 72hPO group mean age was 27, mean 4h APAP level was200, and 81(22%) co-ingested diphenhydramine. No cases developedencephalopathy, abnormal Cr or abnormal INR. Abnormal pH (�7.30) occurred in3 cases in the 20hIV group and 1 case in the 72hPO group: pH resolved with fluidsalone in each case. No transplants or deaths occurred.

Conclusion: This study is the first to compare the IV and PO NAC regimensduring the same time period and in the same region. When administered within 8h ofacute APAP-poisoning, 20hIV NAC was as effective as the longer 36hPO and 72hPOregimens, even in cases where gut-slowing diphenhydramine was ingested. Whetherpreviously published treatment failures adhered to the manufacturer’s protocol isunclear. Further study is needed to determine outcome differences between IV andPO NAC when treatment is initiated �8hours after overdose.

EMF-4 Evaluation of the Recovery of CognitiveFunction Following Treadmill Exercise InFirefighter Protective Gear

Beauchamp, MD G/University of Pittsburgh, Pittsburgh, PA

Background: Firefighter injuries and line-of-duty deaths may be attributable tomultiple factors including hypohydration and heat stress potentially resulting indecrements in cognitive fatigue.

Study Objectives: We sought to characterize and quantify alterations inphysiologic measures, cognitive function, and their recovery following treadmill

exercise in thermal protective clothing (TPC).

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