Abstract： Objective To evaluate the therapeutic efficacy of hemoperfusion in the treatment of intermediate myasthenia syndrome (IMS) following acute organophosphate poisoning (AOPP).Methods Eighty cases of IMS following AOPP,who were admitted to the Emergency Department of our hospital from 2006 to 2011 and had complete clinical records,were divided into HP treatment group (n=36) and non-HP (NHP)treatment group (n=44).The therapeutic efficacy of HP was evaluated by comparing the clinical data of the two groups.Results The HP treatment group showed significantly increased serum cholinesterase activity at 24 h and 72 h after admission (P＜0.05),while the NHP treatment group showed significantly increased serum cholinesterase activity at 72 h after admission (P＜0.05).The serum cholinesterase activity in the HP treatment group was significantly higher than that in the NHP treatment group at 24 h after admission (P＜0.05).Compared with the NHP treatment group,the HP treatment group had significantly decreased total atropine dose,time of ventilatory assistance,length of ICU stay,recovery time from coma,incidence of pulmonary infection,and mortality due to respiratory failure (P＜0.05).There were no significant differences in the incidence of upper gastrointestinal hemorrhage and total mortality between the two groups (P＞0.05).Conclusion Hemoperfusion is an effective therapy for improving clinical symptoms,shorten the course of disease,reducing complications,and decreasing the mortality due to respiratory failure in the patients with IMS following AOPP.