Study of prognostic value of serum and RBC acetyle cholinesterase level in organophosphorus poisoning and its correlation with the outcome

Introduction: Organophosphorus compound (OPC) poisoning has assumed alarming proportions and it is primarily a problem of the developing countries. Serum cholinesterase levels are easier to estimate and usually depressed after OP poisoning. Peradeniya OP poisoning scale has not been studied much in Indian scenario. So, we decided to have first hand information and hence conducted this study. Aim and objectives: To find out severity of patients with OP poisoning by calculating Peradeniya OP Poisoning score, level of plasma and RBC cholinesterase level of patients of OP poisoning on admission before any treatment, and correlate the level with severity and outcome of patients and requirement of ventilator support with OP poisoning. Material and methods: All patients who presented to emergency department with history of poisoning with known compound were taken as study subjects. A detailed history, clinical examination and relevant biochemical investigations were performed. Peradeniya OP poisoning scale was applied to all study subjects and the severity of OP poisoning was graded as mild, moderate, severe. In all study subjects, 3 ml of plain blood was collected on admission before administration of atropine and plasma cholinesterase and RBC cholinesterase was estimated. Results: Most of the patients consumed poison with a suicidal intent. Majority had consumed poison orally. Most patients had consumed 50 ? 100 ml of poison. Quantity of poison consumed did not correlate with severity of poisoning. In this study, requirement of ventilatory support was seen in 16% of patients. Mortality in our study was 9%. Pseudo cholinesterase levels were significantly depressed in patients who required ventilatory support and correlated with mortality. Miosis, Bradycardia, increased respiratory rate, impaired level of consciousness, all correlated well with need for ventilatory support and increased mortality. Peradeniya OP poisoning score of more than 8 correlated in predicting the need for ventilatory support and mortality. RBC and Plasma cholinesterase levels estimation in conjunction with Peradeniya OP poisoning score is a useful parameter for grading severity of OP poisoning and in predicting the need for ventilatory support and mortality. Conclusion: The POP scale and RBC Che and plasma cholinesterase levels both showed a significant association in predicting the need for ventilatory support and outcome. Lower grade of poisoning had a better outcome whereas higher severity of poisoning had a poorer outcome.