Development of a practical prediction scoring system for severe acute organophosphate poisoning

Abstract

Acute organophosphorus poisoning (AOPP) is a serious public health issue, especially in the rural areas. This study was designed to establish a scoring system to assess the risk of cases with severe AOPP. A retrospective cohort study was conducted at two independent hospitals. The derivation cohort included 444 patients with AOPP and the validation cohort included 274 patients. A risk score for patients with severe AOPP was developed. The rates of severe AOPP cases were 20.7% and 20.1% in the derivation and validation cohorts, respectively. A scoring system for severe AOPP risk was developed that included: (1) age >50 years, (2) white blood cell count of >15 × 10⁹ /L, (3) plasma cholinesterase of <360 U/L, (4) plasma albumin of <35 g/L, (5) blood pH <7.3, and (6) lactic acid >3.0 mmol/L. The predicted score in severe cases of AOPP had good accuracy in both the derivation (area under the receiver operating characteristic curve [AUC] 0.88, 95% confidence interval [CI], 0.85-0.92) and validation cohorts (AUC 0.83, 95% CI, 0.77-0.90). A practical bedside prediction scoring system was developed for patients with severe AOPP. The routine use of this scoring system could rapidly assist in identifying patients at higher risk who require more intensive care or transfer to a larger better-equipped hospital.

Keywords: acute organophosphate poisoning; public health; risk prediction; rural areas; scoring system.