Determinants of the Requirements for Ventilatory Support in Patients with Organophosphorus Compound Poisoning

Background: Organophosphorus (OP) compound poisoning is a common cause of medical emergency in the developing world, and it is linked to high morbidity and mortality. Respiratory failure is the critical complication in these cases and requires ventilatory support. Therefore, early identification of clinical and laboratory parameters that can predict ventilatory requirements can lead to an optimal outcome. The current study aimed to determine the determinants of ventilatory support in OP poisoning cases. Material and Methods: This observational study was conducted in a hospital on 40 patients with organophosphorus poisoning. At admission, clinical, demographic, and lab parameters were noted. The perspectives of severity were measured on the basis of the Glasgow Coma Scale (GCS) and Peradeniya OP Poisoning (POP) scale. The two groups of patients were classified: one required ventilatory support, and the other did not require ventilatory support. Statistical analysis was done to determine important predictors for ventilatory support. Results: Among 40 patients, 18(45%) patients were ventilated. Patients who needed ventilation scored considerably lower GCS scores (7.4 ± 2.1 vs 12.8 ± 1.6, p < 0.001) and higher POP scores (9.6 ± 1.8 vs 4.5 ± 1.4, p < 0.001). It also used significant predictors (GCS 8 or less, POP score of more than 7, serum cholinesterase of less than 1000 U/L, bronchorrhea, fasciculations, PaCO2 greater than 45 mmHg, respiratory rate greater than 24/min). The death rate of patients in this study was 22.2%. Conclusion: The important predictors of ventilatory support in OP poisoning are clinical severity parameters, particular clinical presentation, and laboratory parameters. Early identification of these determinants can help in timely intervention, better prognosis, and optimal use of critical care resources.

Keywords: Organophosphorus poisoning, ventilatory support, predictors, POP scale, GCS, respiratory failure.