Organophosphate poisoning: grading the severity and comparing treatment between atropine and glycopyrrolate

Organophosphate poisoning occurs worldwide and often requires admission to an ICU. Grading of patients may be of value to identify high-risk cases but this has never been prospectively evaluated. Conventional treatment with atropine may lead to CNS toxicity, although control of secretions may still be inadequate. We conducted a randomized, controlled trial in 44 patients to compare atropine with glycopyrrolate, a drug that may provide better control of secretions and does not cross the blood-brain barrier. Grading was performed prospectively and compared to outcome. Thirty-nine cases were evaluated (atropine 22, glycopyrrolate 17); the treatment groups were comparable at baseline. No differences could be detected in outcome except for a trend to fewer respiratory infections in the glycopyrrolate group. Thus, treatment with atropine and glycopyrrolate was equally effective. A grading of serious was associated with ventilation, complications, and a prolonged ICU stay. A revised simplified grading is proposed.