Organophosphate poisoning: 10 years of experience in southern Taiwan

Poisoning due to organophosphate pesticides is an important cause of morbidity and mortality worldwide. Although standard treatments involving the administration of atropine and oximes have been used, there remain many controversial areas concerning organophosphate poisoning (OPP). Herein, we present our 10 years of experience in assessing the severity of OPP in southern Taiwan. A retrospective study was performed on patients admitted with OPP. A total of 75 patients (50 males and 25 females) were studied between January 1996 and December 2005. Diagnosis was based on a clinical assessment and serum acetylcholinesterase (AChE) level at the time of hospital admission. The severity of OPP was assessed using the grading system of Bardin et al. The duration and dosage of atropine and palidroxime were recorded. All the biochemical data were analyzed. Sixty-one of the patients had attempted suicide and 14 patients had accidental exposure. The overall mortality rate was 8%. Muscarinic effects were observed in 66 (88%) of the OPP patients and the most frequent symptom was bronchial hypersecretion (52%). Among these three different severity groups, prolonged length of stay, higher infection rates, and higher mortality were found in the life-threatened group. The initial serum C-reactive protein (CRP) level was strongly correlated to the severity grading of the OPP. Nearly half of the patients were admitted to the intensive care unit (ICU) and, of this, 21 patients developed respiratory failure within 72 hours. Low serum AChE levels support the diagnosis of OPP, but no significant association was found between the severity of OPP and serum AChE levels. The grading system of Bardin et al is very helpful for physicians to facilitate the recognition of seriously poisoned subjects, and to permit their early admission to an ICU. Initial serum CRP, an acute phase reactant, had significant value in assessing the severity of the OPP. Although the management of acute OPP is supportive and the recovery rate is high, anti-cholinergic therapy should be used as soon as possible to counteract muscarinic effects. Physicians must be aware of the potential dangers of respiratory failure, which could occur within 72 hours of OPP.