Corrected QT as a Simple Tool for Prediction of Need for Ventilation and Mortality in Acute Organophosphate Poisoning

Abuelfadl, Arwa A.; Shahin, Marwa M.; Alghazaly, Ghada M.

doi:10.21608/mjfmct.2015.47282

Corrected QT as a Simple Tool for Prediction of Need for Ventilation and Mortality in Acute Organophosphate Poisoning

Document Type : Original Article

Authors

¹ Departments of Forensic Medicine and Clinical Toxicology and Faculty of Medicine, Tanta University.

² Forensic Medicine and Clinical Toxicology Department, Faculty of Medicine, Tanta University, Egypt

³ Internal Medicine, Faculty of Medicine, Tanta University

10.21608/mjfmct.2015.47282

Abstract

Organophosphate (OP) toxicity represents a major public health concern, primarily in the developing world. The most common complication from OP exposure is respiratory failure. Nevertheless, cardiac complications have been reported with OP poisoning. This current prospective observational cross sectional study was conducted to evaluate electrocardiographic findings as predictor of major outcome (need for ventilation and mortality) in acute OP toxicity. Thirty eight adult male patients acutely intoxicated by OP were included in the study. The severity of symptoms and signs of acute OP poisoning (OPP) was graded into: mild, moderate and severe grade OPP. Electrocardiography (ECG) was recorded and analyzed for rate, rhythm, axis, voltage, ST and T wave abnormalities, conduction defects, PR interval. The ECG changes induced by acute OPP were graded into: minor, moderate and severe. Corrected QT interval (QTc) was estimated according to Bazett's formula;. Fifteen patients (39.5%) showed a prolonged QTc interval (0.518 ± 0.055 seconds). Both need for ventilation and mortality were noticed in patients with prolonged QTc interval rather than in patients with a normal QTc interval. Significant statistical association was perceived between QTc interval and both manner and route of poisoning, OPP severity, serum cholinesterase level, number of toxogonine ampoules and need for intubation and mechanical ventilation. It is recommended to consider QTc interval as an applicable bedside parameter that helps to identify advanced grade OPP patients, especially those presented by suicidal attempts, severe organophosphate intoxication, oral route of exposure and prolonged QTc interval should be admitted in ICU as high risk patients.

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