Published: 2018-01-18

Clinical profile and outcome of intermediate syndrome in acute organophosphate poisoning

Rajendran Velayudham, Senthilkumar S., Viswanathan Pandurangan


Background: Deaths by acute organ phosphorus poisoning is very common in rural India especially in people associated with agriculture sector. The present study was aimed to study the clinical characteristics of organ phosphorus compound (OPC) poisoning and to assess the associated factors related to the outcome (recovery/death) of intermediate syndrome (IMS).

Methods: This is an observational study conducted on 40 patients showing features of intermediate syndrome at Poison center, Institute of internal medicine, Rajiv Gandhi Government General Hospital, Chennai. Detailed clinical examination was done on the day of admission and daily with close monitoring. All patients included under study will be treated with pralidoxime as per protocol, atropine as required and other supportive measures was provided. Mechanical ventilatory support was provided for patients in respiratory failure. Patients are followed up till the end point of outcome (recovered and discharged/death) that was correlated with type of compound, quantum of exposure, duration of IMS, serum cholinesterase and creatinine kinase levels and respiratory failure.

Result: Patients of age group between 30-40 years are more affected. Males outnumbered the females and most of them are from agriculture sector (65%). Out of 40, on treatment and follow up 34 patients were recovered and 6 were died. Onset of intermediate syndrome ranges between days 2-4 following exposure and duration of symptoms was observed for 5–16 days. Methylparathion was the frequent compound associated with IMS in about 9 cases. Out of 40, 16 had respiratory failure and given ventilator support. Proximal muscle weakness was seen in about 38 patients as common symptom.

Conclusion: The results of the present study concludes that factors such as mode of poisoning, onset of IMS, type of compound, PChE level are not correlated with the outcome of study. Duration of IMS, respiratory failure, ventilator associated pneumonia (VAP), ventilator support duration were associated with outcome of the study. Hence, early recognition of IMS and its associated respiratory paralysis is very important in patients affected with OPC toxicity to prevent morbidity and mortality rate. 


Organophospate compounds, Intermediate syndrome, Mortality

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