A study of clinical parameters and serum pseudocholinesterase levels in predicting the need for ventilatory support in organophosphorus poisoning

Background: Organophosphorus (OP) compound poisoning is one amongst the foremost common poisonings in India because of easy availability, often requiring ICU care and ventilatory support. Clinical research has shown that respiratory failure is the most important cause of death due to Organophosphorus poisoning. This hospital-based, observational study is taken up as an attempt to know the clinical and biochemical factors like serum pseudo cholinesterase levels which can predict the timely need for ventilator support.
Materials and Methods: In this Hospital based Observational study, One hundred consecutive patients presenting with organophosphate poisoning during the study period were included in the study. Detailed History, physical examination, Investigations like Random Blood sugar, Blood Urea, Serum Creatinine, Serum Pseudo Cholinesterase, Chest X-Ray, ABG analysis were studied. Important Biochemical parameters studied were serum electrolytes, serum pseudocholinesterase levels.
Results: The most frequent reason for using ventilation is Respiratory failure, which was seen in76% of the patients, followed by altered sensorium in 22%, increased secretions in 19%, and only 6% are due to IMS. Patients who presented after 2-4 hours of consumption of poison had more chance of getting ventilated. Patients with pupil size less than 1mm and the abdominothoracic pattern of respiration was found to be higher in the ventilated group and was statistically significant. Patients with lower pseudocholinesterase levels were significantly ventilated and had a higher mortality rate. Respiratory failure, aspiration, coma were significantly higher in the ventilated group.
Conclusion: From this study, it can be concluded that older age group, presentation to hospital after 2-4 hours, late stomach wash, high BP, abdominothoracic pattern of respiration, use of accessory muscles, severe poisoning, low GCS, low pseudocholinesterase levels, ABG abnormalities had significantly higher chance of being mechanically ventilated after OP poisoning.