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Original Article

Tranexamic acid to reduce operative blood loss in brain tumor surgery: A meta-analysis

Department of Neurosurgery, Faculty of Medicine Universitas Airlangga – Dr. Soetomo General Academic Hospital, Surabaya, East Java, Indonesia.
Corresponding author: Joni Wahyuhadi, Department of Neurosurgery, Faculty of Medicine Universitas Airlangga – Dr. Soetomo General Academic Hospital, Surabaya, East Java, Indonesia.

This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-Share Alike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.

How to cite this article: Prastikarunia R, Wahyuhadi J, Susilo RI, Haq IB. Tranexamic acid to reduce operative blood loss in brain tumor surgery: A meta-analysis. Surg Neurol Int 2021;12:345.



Major blood loss during neurosurgery may result in a variety of complications, such as potentially fatal hemodynamic instability. Brain tumor and skull base surgery is among the high bleeding risk procedures. Tranexamic acid (TXA) has been found to reduce bleeding events in various fields of medicine.


We searched for all randomized controlled trials published in English or Bahasa which compared the use of TXA with placebo in brain tumor surgery. The studies should include adult patients with intracranial tumor who received TXA before skin incision. The primary and secondary outcomes are intraoperative blood loss and the need of transfusion.


This meta-analysis included a total of 200 patients from three studies. TXA resulted in less blood loss with pooled mean difference of −292.80 (95% CI, −431.63, −153.96, P<0.05). The need of transfusion was not significant between TXA and control group (pooled mean difference −85.36, 95% CI, −213.23 – (42.51), P=0.19).


TXA reduced the volume of blood loss but did not reduce the need of blood transfusion.


Brain tumor
Intraoperative bleeding
Tranexamic acid


Major blood loss during neurosurgical procedures will complicate the treatment and reduce tissue perfusion to vital brain tissue.[1] Excessive blood loss is indeed not desired by neurosurgeons as anemia and related hypoperfusion is deleterious for the brain.[15,24] Anemia was significantly higher in patients who had a blood volume deficit of more than 20% in the postoperative cycle.[29] Brain tumor and skull base surgery is among the procedures most likely to cause high-volume bleeding.[21,25,29]

Tranexamic acid (TXA) is a synthetic derivative of the amino acid lysine that acts as antifibrinolytic. TXA has been used in various setting to reduce blood loss.[10] This meta-analysis aims to analyze the effect of TXA on the volume of blood loss in brain tumor surgery.


Types of studies

We searched for all randomized controlled trials (RCTs), prospective, and retrospective studies published in English or Bahasa which compared the use of TXA with other agents or placebo.

Types of participants

Adult (≥18 years old) patients of either gender diagnosed with intracranial tumor who underwent craniotomy and tumor resection procedure.

Types of interventions

Studies with intravenous administration of tranexamic acid at any dose, by bolus and/or by intravenous drip, will be included. The comparison could be placebo or other antifibrinolytic agents.

Types of outcome measure

Primary outcome

  • Mean blood loss

Secondary outcome

  • The need of PRC and/or whole blood transfusion

  • The need of colloid administration as volume expander

Search methods for identification of studies

The sampling technique in this study was using online literature search results filtering based on the flow of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) according to the PICO that has been determined. We searched PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and ProQuest. Search was limited to papers published between 2010 and 2020. Our search strategy is shown in [Table 1].

Table 1:: Search strategy.

We also searched Google Scholar using any of the possible combination mentioned above.

Data collection and analysis

Selection of studies

The search results were first excluded based on the relevancy of the titles and then on the relevancy of the abstracts. Non-English/non-Bahasa publications were automatically excluded. Full-text articles were then assessed by all authors (JW, RP, IBIH, and RIS) for potentially eligible RCTs. The reasons of exclusion were noted and reported.

Data extraction and management

Demographic data about age, sex, diagnosis, TXA dose and administration, blood loss, and transfusion requirement were collected and presented in [Table 1]. Base hemostasis data were also noted when available.

Assessment of risk of bias in included studies

Risk of bias was assessed by all four authors (JW, RP, IBIH, and RIS). Should conclusion be unmet, a third party from neurosurgery department would be asked to give his/ her opinion. Assessed biases are those mentioned in the Cochrane Collaboration Tool for Assessing Risk of Bias in Randomized Trials published in 2011.[17]

Measures of treatment effect

We undertook statistical analysis using the statistical software, Review Manager 5.4, of the Cochrane Collaboration. We used risk ratios to measure treatment effect for proportions (dichotomous outcomes) among primary and secondary outcomes. Random effect model will be used should evidence of significant heterogeneity is present. A statistically significant difference between intervention and control groups was assumed if the 95% CI did not include the value of no differential effect.

Assessment of heterogeneity

Heterogeneity is addressed by the I2 value on forest plot construction using RevMan 5.4. The statistical model used is switched to random effect should I2 yield the value of ≥50% as the studies are deemed heterogeneous.[16]


Description of studies

Description of studies can be seen on [Appendix 1].

Results of the search

The exclusion processes based on the flow of PRISMA are shown in [Figure 1].

Figure 1:: Study flow diagram according to PRISMA guidelines.

Included studies

After careful consideration from each authors, we decided to include three studies.[19,37,39] All of them were RCTs.

Excluded studies

There are four studies which most likely met our criteria and did report the required data for our primary outcome, but were unfortunately ruled out. Two of them were due to unavailability of full text[23,35] while the other two were due to being published in Arabic[36] and Russian.[27]

Ongoing studies

By the time of our search, we found one study which has not been concluded yet.[11]

Risk of bias in included studies

Risk of bias of included studies was assessed using the Cochrane Collaboration Tool for Assessing Risk of Bias in Randomized Trials published in 2011.[17] The domain of the biases is as follows:

  1. Random sequence generation

  2. Allocation concealment

  3. Blinding of participant and personnel

  4. Blinding of outcome and assessment

  5. Incomplete outcome data

  6. Selective reporting

  7. Other bias

The result of the assessment is shown in [Figure 2].

Figure 2:: Risk of bias of included studies.

Randomization and allocation concealment

Hooda et al. randomized the study’s subjects using computer-generated randomization chart. The TXA infusion was prepared by an anesthesiologist who was not involved in patient management.[19] Sutanto et al. randomized the patient using an enclosed envelope based on the principle of consecutive sampling. It was not clearly stated who prepared the TXA.[37] Vel et al. used a computer-generated randomization chart to allocate the patient. Despite clearly stating that the anesthesiologists were blinded, it was not clear who prepared the drugs.[39]


All three studies did blind the neurosurgeons and the anesthesiologists involved in the surgical procedure.[19,37,39] The person in charge of assessing intraoperative blood loss were blinded in Hooda et al.[19] Despite blinding the neurosurgeons and the anesthesiologist, Sutanto et al. and Vel et al. did not make clear who counted the blood loss, thus we consider this a potential source of bias.[37,39]

Incomplete outcome data

All studies’ subjects were included in the result section. No subjects dropped-out of the studies.[19,37,39]

Selective reporting

We found that all outcomes mentioned in the methods section were reported in the studies.[19,37,39]

Other potential sources of bias

Hooda et al. did not report the standard error of the mean blood loss. An attempt to contact the author has not been fruitful. To complete the missing data, we utilized RevMan Calculator tool by Cochrane which is accessible in their website.[30] Hooda et al. did not mention the mean and standard deviation for the need of transfusion either. Therefore, we used the estimation method described by Shi et al.[34] to find the mean transfusion volume based on the provided median, minimum, and maximum value.

Summary of findings

Summary of findings from each studies and quality of evidence for each outcome can be found in [Tables 2 and 3], respectively.

Table 2:: Summary of findings from each studies.
Table 3:: Quality of evidence for each outcome.

All three included studies reported their results on blood loss and the need of blood transfusion. Sutanto et al. included 40 subjects who were distributed evenly into the study arms. The study compared 20 mg/kg of TXA in 100 cc of NaCl 0.9% with 100 cc of NaCl 0.9%. Either of the infusions was administered for 5–10 min. Baseline PT and aPTT were not different between the two groups. The authors reported that there were patients in the control group who eventually needed fresh frozen plasma (FFP) transfusion (mean 73.50 ± 121.926 cc).[37]

Hooda et al. had 60 study subjects who were equally distributed into TXA group and placebo group. This study administered TXA continuously until the surgery concluded. The dose was 20 mg/kg bolus continued with continuous drip at a dose of 1 mg/kg/h. The comparison was 0.5 ml/kg bolus of NaCl 0.9% continued with 0.025 ml/kg/h NaCl 0.9% continuous drip. Four patients received FFP transfusion in each group, with administered volume of 600 cc and 900 cc in the TXA and placebo group, respectively. Three patients in the TXA group also received platelet transfusion (total transfused volume 250 cc), while two patients in the placebo group received 306 cc of platelet.[19] Vel et al. had the biggest number of patients (100). The intervention dose was 10 mg/kg bolus for 10 min continued with 1 mg/kg/h drip. The placebo dose was equivalent volume of NaCl 0.9% administered as bolus and drip. No FFP transfusion was reported in this study.

The differences between studies are (1) timing and ending of TXA administration, (2) type of tumor, (3) tumor size, (4) embolization history, and (5) pregnancy status, as shown in [Table 2]. Sutanto administered the TXA 30 min before skin incision while Hooda et al. and Vel et al. started the intervention 20 min before skin incision.[19,37,39] Besides the dose, the manner in which TXA was administered was also different. Vel et al. and Hooda et al.[19,39] continued the initial TXA dose with continuous drip while Sutanto et al. did not do so.[37] Sutanto et al. and Hooda et al.[19,37] only included meningioma cases while Vel et al. included all supratentorial tumor.[39]

Effects of interventions

The effect of intervention is shown in [Figure 3]. All studies did assess intraoperative blood loss and the need of PRC and/ or WB transfusion. This meta-analysis amassed a total of 100 patients from three studies. All three studies showed that TXA reduced the volume of blood loss with pooled mean difference of −292.80 (95% CI, −431.63, −153.96, P<0.05). The studies were considered homogenous in terms of blood loss (I2 = 0%). That said, it is important to note that data from Hooda et al. for this meta-analysis were calculated using Cochrane’s tool instead of actual number from the paper. Based on the need of transfusion, the studies were considerably heterogeneous (I2 = 74%). This can be seen on the forest plot as two studies’ CI crossed the zero line, indicating inconsistency in the respective studies. The pooled mean difference for the need of transfusion was −85.36 (95% CI, −213.23 – (42.51), P = 0.19. The funnel plot is also shown in [Figure 4].

Figure 3:: Pooled proportion of (a) blood loss and (b) the need of transfusion.
Figure 4:: Funnel plot of (a) blood loss and (b) the need of transfusion.


This meta-analysis sought to find out if TXA can reduce intraoperative blood loss and blood transfusion in brain tumor surgery. We identified five studies but unfortunately needed to exclude two of them. The included studies yield a total of 200 patients. Massive blood loss from surgical procedure has been associated with mortality and morbidity.[22] A retrospective study found that blood loss exceeding 20% of estimated blood volume in brain tumor surgery strongly correlated with postoperative complications.[21] Another study found that the need of blood transfusion predicted perioperative complications.[31] Therefore, any means to reduce intraoperative blood loss are desirable.

The CRASH-3 trial, the most recent and largest clinical trial about TXA, found that TXA administration in the first 3 h of acute traumatic brain injury (TBI) reduced mortality. However, this trial did not specifically sought intraoperative blood loss or the need of transfusion.[23] In a meta-analysis, TXA reduced intracranial hemorrhage progression in TBI.[41] TXA has also been studied in other fields such as obstetrics and gynecology. Prophylactic use of TXA was found to reduce blood loss and transfusion volume in a meta-analysis.[40]

To this day, the use of TXA in neurosurgery has been limited to TBI or subarachnoid hemorrhage (SAH) cases, primarily due to the fear of thrombotic adverse effects.[12,13] The risk of thrombotic events in TXA theoretically could occur. However, evidence from the Clinical Randomization of an Antifibrinolytic in Significant Hemorrhage-2 trial of TXA in bleeding trauma patients showed a statistically significant reduction in mortality with no increase in thromboembolic effects.[28]

The evidence for use of TXA to treat massive blood loss during intracranial surgery is weak and is even more scarce in terms of brain tumor surgery.[2] In addition to the administration of massive volumes of crystalloids, significant intraoperative bleeding must also be supplemented by several units of blood and blood components.[38] However, the use of these substances can result in hypokalemia, anaphylactic reactions, pulmonary trauma, infection, hemolytic reactions, cardiovascular overload, and sepsis.[6,26,32]

The administration of TXA has demonstrated positive results in spine procedures. In most studies, the preferred TXA dose ranged from 10 mg/kg to 30 mg/kg immediately on performing an incision, a maintenance dose of 0.5–2 mg/kg/h, followed by a preferable 1-mg/kg/h dose until the end of the surgical procedure. High TXA doses did not necessarily increase rates of thromboembolism or convulsions in the case of ASA I and ASA II patients, with no risk factors for thromboembolism or significant renal changes.[4,5,33,42] According to Yutthakasemsunt et al. (2013),[40] the mean overall hemorrhage growth in TBI was smaller in the TXA community relative to the placebo group.

The trials were pooled in a Cochrane study, which concluded that TXA may reduce mortality in TBI patients, but the standard of evidence is poor and there is significant uncertainty.[20] TXA therapy resulted in decreasing the rebleeding incidence, varying from 10.8% to 2.4%, and a reduction in mortality due to rebleeding by 80% in patients diagnosed with SAH within 48 h of first hospitalization, with no rise in drug-related ischemic and vasospasm cases.[18] Grant et al. (2009)[14] recently reported that using TXA during pediatric scoliosis surgery reduced the number of intraoperative PRBC transfusions by 50%. Just two researches[9] found that an antifibrinolytic treatment reduced intraoperative blood loss in children undergoing craniofacial surgery.[8]

The above trials were pooled in a Cochrane study, which concluded that TXA may reduce mortality in TBI patients, but the standard of evidence is poor and there is significant uncertainty.

Headache, fatigue, vomiting, diarrhea, dyspepsia, dysmenorrhea, dizziness, back pain, numbness, phosphenes, and anemia are some of the side effects of TXA when used for an extended period of time.[20] However, if the patients have any history of an active thromboembolic case or illness, DIC, renal dysfunction, or a new coronary or vascular stent, TXA is not recommended.[3] Thrombotic threats have been the most common and concerning adverse events.[20]

Our meta-analysis revealed that TXA reduced intraoperative blood loss at a mean of 292.80 cc (95% CI, −431.63, −153.96). Despite consisting only of 100 subjects and a relatively few included studies, these studies were considered homogenous. The need of transfusion, however, did not seem to be affected by TXA. The pooled mean difference of blood transfusion was −85.36 (95% CI, −213.23 – [42.51]). The range of CI indicated that the TXA group did not always have less blood transfusion. It is also important to recognize the considerable heterogeneity among studies in regard to transfusion volume.

Overall completeness and applicability of evidence

The overall methodological quality of these studies is considered good. There was, however, a considerable heterogeneity in respect to the secondary outcome. One study did not provide the standard error of both mean blood loss and mean blood transfusion. The inclusion criteria between studies were quite similar as well.

Quality of the evidence

We deem that the conclusion for both our primary and secondary outcomes belongs to moderate and low-quality evidence, respectively, mainly due to the presence of at least one type of bias in all of the studies and the inconsistency with regard to transfusion volume. The studies were also heterogeneous in terms of transfusion volume.

Agreements and disagreements with previous meta-analysis or review

We are unaware of any such meta-analysis or review which compare different dose of mannitol for brain tumor surgery.


Implications for practice

TXA is beneficial in reducing the volume of blood loss. However, this does not always translate to less blood transfusion.

Implications for research

Further research to assess (1) the most effective dose and (2) the timing of TXA administration is needed, as they are among the points not covered by this meta-analysis.

Declaration of patient consent

Patient’s consent not required as there are no patients in this study.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


  1. , , , , , , . Blood transfusion indications in neurosurgical patients: A systematic review. Clin Neurol Neurosurg. 2017;155:83-9.
    [Google Scholar]
  2. , , . Use of tranexamic acid as a rescue measure to achieve hemostasis after massive blood loss in a pediatric neurosurgical patient. J Neurosurg Anesthesiol. 2011;23:376-7.
    [Google Scholar]
  3. . Systematic review of tranexamic acid adverse reactions. J Pharmacovigi. 2015;3:4.
    [Google Scholar]
  4. , , , , , , . A randomized controlled trial of low-dose tranexamic acid versus placebo to reduce red blood cell transfusion during complex multilevel spine fusion surgery. World Neurosurg. 2018;110:e572-9.
    [Google Scholar]
  5. , , , , , , . Efficacy of tranexamic acid on surgical bleeding in spine surgery: A meta-analysis. Spine J. 2015;15:752-61.
    [Google Scholar]
  6. , , , , . Effectiveness and safety of tranexamic acid in spinal deformity surgery. J Korean Neurosurg Soc. 2017;60:75-81.
    [Google Scholar]
  7. , , , , . Efficacy of aprotinin in children undergoing craniofacial surgery. J Neurosurg. 2003;99:287-90.
    [Google Scholar]
  8. , , , , , , . Intraoperative tranexamic acid reduces blood transfusion in children undergoing craniosynostosis surgery. Anesthesiology. 2011;114:856-61.
    [Google Scholar]
  9. , . Tranexamic acid: A review of its use in surgery and other indications. Drugs. 1999;57:1005-32.
    [Google Scholar]
  10. . Effects of tranexamic acid on death, disability, vascular occlusive events and other morbidities in patients with acute traumatic brain injury (CRASH-3): A randomised, placebo-controlled trial. Lancet. 2019;394:1713-23.
    [Google Scholar]
  11. Efficacy of Tranexamic Acid in Brain Tumor Resections Full Text View. Available from: [Last accessed on 2020 Aug 28]
    [Google Scholar]
  12. , , , . Antifibrinolysis with tranexamic acid in aneurysmal subarachnoid hemorrhage: A consecutive controlled clinical trial. Neurosurgery. 1981;8:158-65.
    [Google Scholar]
  13. , , , , , , . Tranexamic acid, a widely used antifibrinolytic agent, causes convulsions by a γ-aminobutyric acidA receptor antagonistic effect. J Pharmacol Exp Ther. 2002;301:168-73.
    [Google Scholar]
  14. , , , , , . Perioperative blood transfusion requirements in pediatric scoliosis surgery. J Pediatr Orthop. 2009;29:300-4.
    [Google Scholar]
  15. , . Red blood cell transfusion in neurosurgical patients. Curr Opin Anaesthesiol. 2014;27:470-3.
    [Google Scholar]
  16. , , , , , , . The cochrane collaboration’s tool for assessing risk of bias in randomised trials. BMJ. 2011;343:d5928.
    [Google Scholar]
  17. , , , , , , . Cochrane Handbook for Systematic Reviews of Interventions. United States: John Wiley and Sons; .
    [Google Scholar]
  18. , , , , , . Immediate administration of tranexamic acid and reduced incidence of early rebleeding after aneurysmal subarachnoid hemorrhage: A prospective randomized study. J Neurosurg. 2002;97:771-8.
    [Google Scholar]
  19. , , , , , . Effect of tranexamic acid on intraoperative blood loss and transfusion requirements in patients undergoing excision of intracranial meningioma. J Clin Neurosci. 2017;41:132-8.
    [Google Scholar]
  20. , . Tranexamic acid in neuroanesthesia and neurocritical care: Time for its critical appraisal. J Neuroanaesth Crit Care. 2019;6:257-66.
    [Google Scholar]
  21. , , . Perioperative management of complex skull base surgery: The anesthesiologist’s point of view. Neurosurg Focus. 2002;12:e5.
    [Google Scholar]
  22. , , , , , , . The independent association of massive blood loss with mortality in cardiac surgery. Transfusion. 2004;44:1453-62.
    [Google Scholar]
  23. , , , , , . Effect of tranexamic acid on blood loss and the quality of surgical field in meningioma resection surgery. J Neuroanesthesiol Crit Care. 2015;2:157-8.
    [Google Scholar]
  24. , , , . Anemia management after acute brain injury. Crit Care. 2016;20:152.
    [Google Scholar]
  25. , , , , , , . Postoperative complications after craniotomy for brain tumor surgery. Anaesth Crit Care Pain Med. 2017;36:213-8.
    [Google Scholar]
  26. , , , , , . Erythropoietin therapy and acute preoperative normovolaemic haemodilution in infants undergoing craniosynostosis surgery. Pediatr Anesth. 2003;13:392-6.
    [Google Scholar]
  27. , , , . Using of tranexamic acid (Tranexam) for prevention and correction of coagulopathy during brain tumors removal. Anesteziol Reanimatol. 2011;4:61-6.
    [Google Scholar]
  28. , , , , , , . CRASH-2 (clinical randomisation of an antifibrinolytic in significant haemorrhage) intracranial bleeding study: The effect of tranexamic acid in traumatic brain injury a nested, randomised, placebo-controlled trial. Health Technol Assess. 2012;16:3-12.
    [Google Scholar]
  29. , , , , . Effect of intraoperative blood loss on perioperative complications and neurological outcome in adult patients undergoing elective brain tumor surgery. J Neurosci Rural Pract. 2019;10:631-40.
    [Google Scholar]
  30. , , , , . Frequency and predictors of complications in neurological surgery: National trends from 2006 to 2011: Clinical article. J Neurosurg. 2014;120:736-45.
    [Google Scholar]
  31. , , , , , , . Factors predicting early deterioration in mild brain trauma: A prospective study. Brain Inj. 2013;27:1666-70.
    [Google Scholar]
  32. , , , , , , . Minimal dose of tranexamic acid is effective in reducing blood loss in complex spine surgeries: A randomized double-blind placebo controlled study. Asian Spine J. 2018;12:484-9.
    [Google Scholar]
  33. , , , , , , . Optimally estimating the sample standard deviation from the five-number summary. Res Synth Methods. 2020;11:641-54.
    [Google Scholar]
  34. , . Use of tranexamic acid to reduce intraoperative bleeding in craniotomy for meningioma patients. Anesth Analg. 2018;126:384-6.
    [Google Scholar]
  35. , , , , , . Assessment of the effect of tranexamic acid on intraoperative blood loss in patients undergoing craniotomy for tumor excision. JAP. 2017;8:61-70.
    [Google Scholar]
  36. , , . Effects of intravenous tranexamic acid on blood loss and transfusion requirements in tumor removal surgery of suspected meningioma. J Neuroanestesi Indones. 2019;8:8-16.
    [Google Scholar]
  37. , , , , , . Effect of low dose tranexamic acid on intra-operative blood loss in neurosurgical patients. Saudi J Anaesth. 2015;9:42.
    [Google Scholar]
  38. , , , , , . Effect of low dose tranexamic acid on intra-operative blood loss in neurosurgical patients. Saudi J Anaesth. 2015;9:42-8.
    [Google Scholar]
  39. , , . Prophylactic use of tranexamic acid reduces blood loss and transfusion requirements in patients undergoing cesarean section: A meta-analysis. J Obstet Gynaeco Res. 2019;45:1562-75.
    [Google Scholar]
  40. , , , , , . Tranexamic acid for patients with traumatic brain injury: A randomized, double-blinded, placebo-controlled trial. BMC Emerg Med. 2013;2013:13-20.
    [Google Scholar]
  41. , , , . Tranexamic acid for traumatic brain injury: A systematic review and meta-analysis. Am J Emerg Med. 2014;32:1503-9.
    [Google Scholar]
  42. , , , , , , . Effectiveness of tranexamic acid in reducing blood loss in spinal surgery: A meta-analysis. BMC Musculoskelet Disord. 2014;15:448.
    [Google Scholar]
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