ObjectiveTo discuss the effectiveness and safety of intravenous application of tranexamic acid in reducing the blood loss in the perioperative period of lumbar fusion surgery. MethodsA retrospective study of 68 patients with degenerative lumbar spinal stenosis with lumbar instability who were treated with lumbar fusion surgery from March 2013 to March 2014 in West China Hospital was carried out. The patients were divided into tranexamic acid group and control group according to whether tranexamic acid was used. After induction of anesthesia, tranexamic acid was given by intravenous drop to patients in the tranexamic acid group, while the control group did not receive any hemostatic drug. The red blood cell count, hemoglobin, mean corpuscular volume, prothrombin time, activated partial thromboplastin time, fibrinogen metaglobulin, intraoperative blood loss, postoperative blood loss, and blood transfusion volume before and after operation were compared. And we also observed whether there was pulmonary embolism or deep vein thrombosis incident. ResultsIt showed no significant difference in intraoperative blood loss between the two groups, but the tranexamic acid group had less blood loss after operation than that of the control group (P<0.05). The tranexamic acid group had a higher red blood cell count, hemoglobin and mean corpuscular volume after operation than that of the control group (P<0.05). There was no significant difference between the two groups in prothrombin time, activated partial thromboplastin time, fibrinogen metaglobulin before and after operation (P>0.05). The pulmonary embolism and deep vein thrombosis were not found in the two groups. ConclusionIntravenous application of tranexamic acid is safe and effective in posterior lumbar fusion surgery. It can reduce the postoperative blood loss significantly, without increasing the risk of pulmonary embolism and deep vein thrombosis.