Clinical intervention study of low molecular heparin (LMH) and coagulopathy in critical post-surgical patients with infection WAN Lin-jun, HUANG Qing-qing, YUE Jin-xi, et al. Department of Surgical Intensive Care Unit, the Second Affiliated Hospital of Kunming Medical College, Kunming650101, China Corresponding author: WAN Lin-jun, E-mail: wanlj2003@yahoo.com.cn Abstract Objective To observe the index of blood coagulation, intervention treatment and safety of low molecular heparin (LMH) in critical post-surgical patients with infection. Methods The clinical data of 200 critical post-surgical patients with infection in the Department of SICU of Second Affiliated Hospital of Kunming Medical College between October 2006 and August 2009 as study group and 100 non-infection patients as comparative group in synchronization. The study group was randomly divided into infection group that 100 patients were treated regularly of ICU, and LMH treatment group that 100 patients were taken 40mg LMH by a subcutaneous injection twice per day on regular treatment in post-surgical 8 hours. All patients of study group and comparative group were observed regularly by ICU. PT, APTT, TT, FIB and side effect of Heparin such as hemorrhage in 7 days were observed. The patients accorded with the transfer criteria of ICU were gotten out from ICU during observation time. Results （1）PT and APTT in all patients with infection compared with non-infection were time-lapse in post-surgical 1 to 7 days (P＜0.01), and TT was time-lapse a little bit but located in normal range in post-surgical 6 to 7 days. FIB in all groups were similar in the first day (P＞0.05). However, FIB in all of infection patients increased compared with that of comparative group in 2 to 7 days (P＜0.01). (2) PT in LMH treatment group was shorter than infection group’s in post-surgical 4 to 7 days. APTT was time-lapse compared with that of infection group in post-surgical 5 to 7 days. TT did not change. FIB in LMH treatment group decreased compared with that of comparative infection group (P＜0.01). (3) The proportion of getting out from ICU in LMH treatment group was higher than that of regular treatment group as observation was over (P＜0.01). The time in ICU was not different (P＞0.05). (4) Injection sites of three patients in LMH treatment group presented ecchymosis. Conclusion Critical post-surgical patients with infection usually accompany by phenomenon of coagulation activation and fibrinolytic inhibition. Early treatment by LMH in post-surgical patients with infection might improve coagulation activation and fibrinolytic inhibition, increase effect of combined therapy and have good safety.