High-Dose Tranexamic Acid Reduces Blood Loss in Extensive Spine Surgery
Spinal deformity surgery can be associated with substantial blood loss. This in turn can lead to intra-operative stroke, cardiac ischemia and or shock. If needed, large-volume blood transfusions can lead to pulmonary or cerebral edema, coagulopathies, as well as post-operative issues, including but not limited to, blood-borne diseases and transfusion reactions.
Posterior vertebral column resection (PVCR) is a surgical technique whereby the spinal deformity is corrected by removing an entire vertebral body. A recent study conducted in China found that treating patients with high doses of tranexamic acid (TXA) can cut down significantly on intraoperative blood loss and reduce the amount of blood transfusion(s) needed while performing spinal deformity surgery and PVCRs.
"In our study, high doses of TXA have been shown to effectively control blood loss and reduce the transfusion requirement. This effect was more apparent in patients receiving PVCR," the authors stated as published in The Spine Journal. In the tranexamic acid group, there was a 57.4% reduction in blood loss in patients who had PVCR, and a 39.8% reduction in blood loss in patients without PVCR. No adverse reactions were seen, they stated.
The study included 59 patients at the 2nd Affiliated Hospital of Kunming Medical University in Kunming, Yunan Province, China, who underwent corrective surgery for spinal deformities, including posterior vertebral column resections. They were divided into two groups, 26 of whom were treated with tranexamic acid and 33 in a control group who were not. Eight patients in the tranexamic acid group and nine patients in the control group underwent PVCR. There were 12 patients under age 18 in the tranexamic acid group and 15 in the control group. Both groups were similar in terms of demography and surgical traits.
The tranexamic acid group received an intravenous loading dose of 100 mg/kg over 20 minutes before skin incision. This was followed by a maintenance infusion until skin closure. Patients in the control group received an infusion of a similar volume of saline.
Patients in the tranexamic acid group were examined before and after surgery using vascular ultrasound to look for any deep vein thrombosis in their legs. Blood loss was determined from the suction, cell saver, and by weighing sponges on an hourly basis. The total amount of blood transfused was calculated from the volume of the cell saver and units of packed red blood cells used. Coagulation parameters, complete blood count, liver and renal functions were tested before and after each surgery.
Blood loss in the patient group treated with tranexamic acid was 2441 ± 1666 ml, while that of the control group was 4789 ± 4719 ml; a statistically significant difference. Patients in the tranexamic acid group required significantly fewer transfusions than did those in the control group.
Blood loss and blood transfusion requirements were all significantly lower in the tranexamic acid group, compared with the control group among both PVCR patients and non-PVCR patients, the authors stated.
About Tranexamic Acid
Intravenous tranexamic acid is a fibrinolysis inhibitor that is used to prevent excessive blood loss during surgery. It limits blood loss by preventing the dissolution of clots that form in the small caliber tissue vessels. It is frequently used in cardiac, liver, total joint, and vascular surgery. Brand names for intravenous tranexamic acid are Cyklokapron and Transamin.
To date there are no established guidelines on how much tranexamic acid to use in controlling bleeding during spine surgery, nor have there been any studies on its use during PVCR. In yet another study from China, after a randomized controlled trial, the authors concluded that TXA reduced post-operative blood loss by 29% during lumbar spine surgery.
A further recently published North American randomized control trial in adolescent patients undergoing scoliosis surgery found that tranexamic acid and epsilon-aminocaproic acid reduced operative blood loss but not the overall transfusion rate. They further found that tranexamic acid is more effective at reducing postoperative drainage and total blood losses compared with epsilonaminocaproic acid.
In summary, the evidence exists supporting the effectiveness of TXA in reducing blood loss during spinal surgery. The evidence also suggests the risk associated with its use is very low; however, the exact dosing still needs to be investigated.