Topical application of tranexamic acid (TXA) before wound closure has been found to have better postoperative blood conserving effects in elective spine surgery, compared to intravenous administration and local infiltration of the drug. This is the finding of a single-centre, randomised control trial carried out by Viswanadha Arun-Kumar (Mallika Spine Centre, Guntur, India), the findings of which were published in Global Spine Journal.
Arun-Kumar concluded that all three of the different modes of TXA administration were found to be effective in reducing blood loss in the treated groups compared to the control group, with a 67% reduction in the need for blood transfusion in the topical application (tTXA) group, 55.5% reduction in the intravenous group (ivTXA) group, and 33% reduction in the locally administered group (loTXA).
TXA is an antifibrinolytic drug (synthetic lysine analogue) acting by competitive blocking the lysine binding site of plasminogen, plasmin, and tissue plasminogen activator—preventing clot breakdown and improving impaired platelet function.
The effect of tTXA is widely established in joint replacement procedures where it is applied via intra-articular injection after closure of the wound or through irrigation into the wound just before closure, Arun-Kumar noted in his study. However, according to Arun-Kumar, the consensus regarding the usage of tTXA in spine surgery has not been clearly established due to inconclusive results. Local infiltration of tranexamic acid has been studied in trauma surgeries where intramuscular or subfascial infiltration was given before surgery or before wound closure. The study sought to evaluate the efficacy of the three methods of administering TXA in reducing blood loss in elective spine surgery.
The study cohort included a total of 104 patients (55 female and 49 male) undergoing instrumented spine surgery between October 2017 and August 2018. All the cases included in the study were diagnosed with degenerative grade 1 or 2 spondylolisthesis, with the patients undergoing posterior spinal instrumentation and interbody fusion.
Patients were randomised into one of four groups (n=26). The ivTXA group received intravenous administration of TXA one hour prior to surgery, loTXA underwent local infiltration of TXA bilaterally into the paraspinal musculature prior to incision, tTXA group members underwent topical application of TXA just before wound closure, and the remainder of patients were assigned to the control group. Outcome measures included intraoperative blood loss, postoperative blood loss, need for blood transfusion, length of hospital stay, and hematological parameters.
Estimation of intraoperative blood loss was achieved by applying a formula factoring in the weight of surgical sponges, the weight of dry sponges, the volume of suction canisters and the volume of irrigation fluids applied. At the end of the surgery, a 12-sized closed vacuum suction drain was placed deep into the fascia before closure. The amount of total drainage at 24, 48 and 72 hours postoperatively was recorded.
Arun-Kumar found that trends of drain collection were declining from postoperative day one to three in all of the patient groups, with the control group having the highest amount of collection at any given time. On postoperative day one, he found, the control group had 316.3±110.1mL, loTXA had 241.4±110.9mL, ivTXA had 190±112.7mL, and tTXA had 67.3±32.6 mL of average drain collection. Arun-Kumar noted that the drain amount of loTXA and ivTXA was not significantly different on postoperative day three, however, a significant difference was noted in tTXA, which recorded lowest amount of collection on all postoperative days when compared with other groups.
In discussing the findings, Arun-Kumar wrote that amount of drain collection is one of the most significant findings of the study. Regarding the reduction in the need for blood transfusion in each of the three groups, he wrote: “This confirms that TXA irrespective of route of administration decreases the requirement of blood transfusions. However, need for postoperative transfusions is less in tTXA followed by ivTXA and loTXA.”
Arun-Kumar concluded that the findings of the study opens up the field for further research on the efficacy of local TXA which needs to be studied in complex spine procedures where the blood loss is expected to be even more, adding that there is currently no literature on loTXA in spine surgery that has evaluated, through a prospective cohort, with a larger sample size and observed its long-term effects related to fusion. Furthermore, he noted the dose-related response of TXA also needs to be studied with low and high dosing of loTXA and tTXA to help in determining the optimal timing and adequate dosing of the drug, and whether a combination of loTXA/ivTXA prior to incision and tTXA before closure could maximise benefits of reducing blood loss needs further research.
Speaking to Spinal News International Arun-Kumar commented: “Intravenous TXA has been studied extensively and its role in conservation of intraoperative blood loss has been clearly established. However, the newer methods of administration such as topical application and local infiltration has been described in this study which has comparable blood conserving effects thereby enabling us to eliminate the systemic side effects of ivTXA.”