Clinical Relevance of Oxime and Sodium Bicarbonate Therapy for Acute Organo-phosphate Poisoning - Still a Dilemma

Objective: To evaluate the efficacy of oxime and sodium bicarbonate therapy in organophos-phate poisoning, and to correlate it with objective endpoints such as AChE status, survival, need for mechanical ventilation and atropine consumption. Methods: Retrospective study of 109 patients with OP poisoning, treated in the National Poison Control Centre, Belgrade (January 2003-June 2007) was performed. The patients were analyzed according to the class of OP (96 had dimethylphosphoryl and 13 diethylphosphoryl compounds poisoning) and the applied therapy: Group I - atropine and bicarbonate (17); Group II - atropine, oxime and bicarbonate (10); Group III - atropine and oxime (40); Group IV - atropine (42). Pralidoxime methylsulphate (4 g/ day) and bicarbonate (5 mEq/kg/day) were administered as long as OP was present in biological samples. Results: The majority (59.6%) of patients had severe and fatal poisoning (PSS 3 and 4). According to their AChE status patients were divided to 4 groups: A. No significant inhibition; B. 21-50%; C. 11-20%; D. less than or equal to 10%. The lowest rate of AChE inhibition was registered in patients from Group IV (p