en Electrocardiographic Manifestations of Benzodiazepine Toxicity تخصصي Special پژوهشي Research <b>Background: </b>The aim of this study was to evaluate and compare the clinical and ‎electrocardiographic (ECG) manifestations of benzodiazepines (BZs).‎ <br><b>Methods:</b> In this retrospective study, all BZ-poisoned patients hospitalized at Loghman ‎Hakim Hospital between September 2010 and March 2011 were evaluated. Patients’ ‎information including age, sex, time elapsed between the ingestion and presentation, ‎and type of the BZ used were extracted from the patients' charts and recorded. ECGs ‎on presentation to the emergency department (ED) were evaluated and parameters ‎such as PR interval, QRS duration, corrected QT, amplitude of S wave in lead I, height ‎of R wave and R/S ratio in the lead aVR were also measured and recorded.‎ <br><b>Results: </b>Oxazepam, chlordiazepoxide, lorazepam, alprazolam, diazepam, and ‎clonazepam were ingested by 9 (3%), 13 (4.4%), 29 (9.9%), 105 (35.8%), 65 (22.2%), ‎and 72 (24.6%) patients, respectively. Mean PR interval was reported to be 0.16 ± 0.03 ‎sec and PR interval of greater than 200 msec was detected in 12 (4.5%) patients. Mean ‎QRS duration was 0.07 ± 0.01sec and QRS≥120 msec was observed in 7 (2.6%) ‎cases. ‎ <br><b>Conclusion:</b> Diazepam is the only BZ that does not cause QRS widening and ‎oxazepam is the only one not causing PR prolongation. It can be concluded that if a ‎patient refers with a decreased level of consciousness and accompanying signs of BZ ‎toxicity, QRS widening in ECG rules out diazepam, whereas PR prolongation rules out ‎oxazepam toxicity.‎ Benzodiazepines, Electrocardiogram, Manifestations, Poisoning.‎ Benzodiazepines, Electrocardiogram, Manifestations, Poisoning.‎ 952 955 http://ijt.arakmu.ac.ir/browse.php?a_code=A-10-2-136&slc_lang=en&sid=1 Nahid Kazemzadeh ناهید کاظم زاده 10031947532846002290 10031947532846002290 No Department of Forensic Medicine and Toxicology, Iran University of Medical Sciences, Tehran, Iran.‎ Department of Forensic Medicine and Toxicology, Iran University of Medical Sciences, Tehran, Iran.‎ Saeed Mohammadi سعید محمدی drsm1980@gmail.com 10031947532846002291 10031947532846002291 Yes Department of Forensic Medicine and Toxicology, Iran University of Medical Sciences, Tehran, Iran.‎ Department of Forensic Medicine and Toxicology, Iran University of Medical Sciences, Tehran, Iran.‎ Mohammadali Emamhadi محمدعلی امام هادی 10031947532846002292 10031947532846002292 No Department of Forensic Medicine and Toxicology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.‎ Department of Forensic Medicine and Toxicology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.‎ Abdollah Amirfarhangi عبداله امیرفرهنگی 10031947532846002293 10031947532846002293 No ‎ Department of Cardiology, Hazrat Rasoul Akram(p)Hospital, Iran University of Medical Sciences, Tehran, Iran.‎ ‎ Department of Cardiology, Hazrat Rasoul Akram(p)Hospital, Iran University of Medical Sciences, Tehran, Iran.‎ Hossein Sanaei-Zadeh حسین صناعی زاده 10031947532846002294 10031947532846002294 No Emergency Department /Division of Medical Toxicology, Hazrat Ali-Asghar (p) Hospital, Shiraz University of ‎Medical Sciences, Shiraz, Iran.‎ Emergency Department /Division of Medical Toxicology, Hazrat Ali-Asghar (p) Hospital, Shiraz University of ‎Medical Sciences, Shiraz, Iran.‎