Effectiveness of tranexamic acid in reducing blood loss in spinal surgery: a meta-analysis.

BACKGROUND: The aim of present meta-analysis was to evaluate the effectiveness of tranexamic acid (TXA) use in reducing blood loss and the related thrombotic complications in spinal surgery. METHODS: Three databases (MEDLINE, EMBASE, and the Cochrane Library) were searched through October 2012 to identify the relevant randomized controlled trials (RCTs) regarding the TXA effective in spinal surgery. Mean differences (MDs) of blood loss, blood transfusions, and postoperative partial thromboplastic time (PTT), odds ratios (ORs) of blood transfusion and thrombotic complication in TXA-treated group compared to placebo group were extracted and combined using random-effect meta-analysis. RESULTS: A total of 6 RCTs comprising 411 patients were included in the meta-analysis according to the pre-defined selection criteria. TXA-treated group had significantly less amount of blood loss and blood transfusions per patient, and had smaller proportion of patients who required a blood transfusion compared with the placebo group. The use of TXA can significantly reduce the postoperative PTT with weighted MD of -1.59 [(95% confidence interval (CI):-3.07, -0.10] There is a null association between thrombosis complications and the use of TXA. CONCLUSION: We conclude that the use of TXA in patients undergoing spinal surgery appears to be effective in reducing the amount of blood loss, the volume of blood transfusion, the transfusion rate, and the postoperative PTT. However, data were too limited for any conclusions regarding safety. More high-quality RCTs are required before recommending the administered of TXA in spinal surgery.

[A modified goat model of acute spinal cord compression injury from a percutaneous balloon catheter: method feasibility and preliminary observation].

OBJECTIVE: To establish a goat model of acute spinal cord compression injury through a modified percutaneous technique with a Foley double-lumen urine catheter and explore the method feasibility and preliminary observation. METHODS: Twelve adult male Chongming goats were randomly divided into 3 groups:control (A, n = 4), 0.5 ml compression (B, n = 4) and 1 ml compression (C, n = 4). After local anesthesia, all animals received epidural balloon catheter (5Fr) insertion via a percutaneous trans-lumbosacral interlaminar space technique that mimicked the method used in vascular access for angiography. The balloon catheter was advanced under fluoroscopic guidance until its distal tip reached the middle of T6 level.One week later, for groups B and C, the balloon was inflated by half-strength contrast material, 0.5 ml and 1 ml, respectively. The balloon was left inflated for 30 min and then deflated. The images of computed tomography (CT) and magnetic resonance (MR) were taken before and after surgical procedures.Quantitative assessment of spine canal occupying rate was accomplished by an off-line software program based on CT results. Motor function was assessed by the modified Tarlov scale. Two animals of each group were sacrificed after a total observation period of 48 h and 72 h respectively.Spinal cords from the injured level were then obtained for pathologic examinations. RESULTS: All animals underwent successful catheterization occupying 6.8%±0.7% (Group A), 6.7%±0.7% (Group B) and 6.6%±0.6% (Group C) of spine canal respectively. After inflation, the occupying rate of groups B and C achieved 43.4%±2.5% and 88.1%±2.3% respectively.Ventral compression of spinal cord was noted on MR images.Hindlimb movement remained normal after catheter insertion in all groups. All animals in group B and C became paraplegic after inflation. And a positive correlation existed between injection volume and Tarlov score. Pathological findings confirmed neuron atrophy, increased gap around neurons, mild demyelination and vacuolar degeneration both in groups B and C at 48 h after injury. Pathological changes deteriorated at 72 h after injury. CONCLUSION: The results of behavioral evaluation, radiographic images and pathological examination reveal an evidence of acute spinal cord injury. Percutaneous epidural balloon catheter insertion differs from previous techniques by avoiding surgical exposure and associated artifacts, yet it offers injury mechanisms similar to those of human spinal cord injury. As a new means of modeling spinal cord injury in animals, this technique has many potential applications.