The predictive value of the electrocardiographic changes in determining short-term prognosis after intentional organophosphate poisoning

Abstract

Objective To study the value of the different electrocardiographic changes in acute organophosphate poisoning.Methods A total of 103 patients with acute organophosphate (OP) poisoning were included and their relevant ECG abnormalities were investigated.ECG recordings were taken on arrival at the emergency department and 24 hours after admission.ECG analysis included heart rate,ST-T abnormalities,conduction defects,measurement of PR and QTc intervals,and the difference in QTc intervals between two ECG readings (△QTc).The correlation was assessed between ECG changes and the severity of poisoning.Results QTc and age were significant risk factors for respiratory failure and mortality.PR was significant risk factor for respiratory failure.The prolonged QTc interval was found in 100％ of patients 24 hours after poisoning.The area under receiver operating characteristic (ROC) curves of the blood cholinesterase activity (CHE),QTc and △QTc for respiratory failure were 0.033 (95％ CI:0.004-0.063),0.829 (95 ％ CI:0.739-0.918) and 0.943 (95％ CI:0.888-0.998) respectively.And the area under ROC curves of the CHE,QTc and △QTc for death were 0.052 (95％ CI:0.01-0.094),0.693 (95％ CI:0.559-0.826) and 0.895 (95％ CI:0.814-0.977) respectively.Conclusions The△QTc may be a novel and better predictive factor for determining short-term prognosis after intentional organophosphate poisoning. Key words: Acute organophosphate poisoning; Electrocardiographic; QTc interval