ACUTE ORGANOPHOSPHATE POISONING;

ELECTROCARDIOGRAPHIC MANIFESTATIONS

Abstract

Introduction: Organophosphate poisoning (OP) is a serious public health
problem. Cardiac manifestations are seen in majority of patients with OP and may range from
sinus tachycardia to more serious ventricular tachyarrhythmias. Objectives: To determine
the electrocardiographical manifestations of acute organophosphate poisoning at a tertiary
care hospital. Study Design: Observational study. Setting: Department of Medicine, Abbasi
Shaheed Hospital, Karachi. Period: February 2011 to August 2011 over a period of six months.
Patients and methods: All patients of either sex presenting with the history or evidence of
exposure to organophosphorus compounds within 24 hours with characteristics manifestations
of organophosphate poisoning were included in the study. Electrocardiographic manifestations
were observed before the institution of medical therapy. Results: A total of 123 patients, 81
(65.9%) male and 42 (34.1%) female were included in the study. The Mean (+SD) age of
the study participants was 29.07 (+ 9.61) years. Majority (74%) patients had age <35 years
and 78 (63.4%) patients in this study had time duration of <6 hours between ingestion of
organophosphorus and institution of therapy. The overall electrocardiographic changes were
observed in 86.2% of patients. Out of these, ST elevation was seen in 19.8%, T-wave inversion in
17.9%, prolonged PR interval in 9.4%, atrial fibrillation in 6.6% and prolonged QTc interval seen
in 46.2%. Conclusion: Electrocardiographical changes are common manifestation of acute
organophosphate poisoning. Prolonged QTc interval and ST segment elevation are the most
common finding in our patients. As these changes in ECG can lead to serious consequences,
therefore it should be carefully evaluated in every patient with OP so that early intervention can
be done.