Tranexamic acid for the reduction of bleeding during functional endoscopic sinus surgery

Chronic rhinosinusitis, with or without nasal polyps, can have a major impact on a person's quality of life. Treatment is usually conservative and may include nasal saline, intranasal corticosteroids, antibiotics or systemic corticosteroids. If these treatments fail endoscopic sinus surgery can be considered. During surgery, visibility of the surgical field is important for the identification of important anatomic landmarks and structures that contribute to safety. Impaired visualisation can lead to complications during surgery, inability to complete the operation or a longer duration of surgery. Different methods are used to decrease intraoperative bleeding, including induced hypotension, topical or systemic vasoconstrictors or total intravenous anaesthesia. Another option is tranexamic acid, an antifibrinolytic agent, which can be administered topically or intravenously.

To assess the effects of peri-operative tranexamic acid versus no therapy or placebo on operative parameters in patients with chronic rhinosinusitis (with or without nasal polyps) who are undergoing functional endoscopic sinus surgery (FESS).

The Cochrane ENT Information Specialist searched the Cochrane ENT Trials Register; Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid Embase; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 10 February 2022.

Randomised controlled trials (RCTs) comparing intravenous, oral or topical tranexamic acid with no therapy or placebo in the treatment of patients (adults and children) with chronic rhinosinusitis, with or without nasal polyps, undergoing FESS.

We used the standard methodological procedures expected by Cochrane. Primary outcome measures were surgical field bleeding score (e.g. Wormald or Boezaart grading system), intraoperative blood loss and significant adverse effects (seizures or thromboembolism within 12 weeks of surgery). Secondary outcomes were duration of surgery, incomplete surgery, surgical complications and postoperative bleeding (placing of packing or revision surgery) in the first two weeks after surgery. We performed subgroup analyses for methods of administration, different dosages, different forms of anaesthesia, use of thromboembolic prophylaxis and children versus adults. We evaluated each included study for risk of bias and used GRADE to assess the certainty of the evidence.

We included 14 studies in the review, with a total of 942 participants. Sample sizes in the included studies ranged from 10 to 170. All but two studies included adult patients (≥ 18 years). Two studies included children. Most studies had more male patients (range 46.6% to 80%). All studies were placebo-controlled and four studies had three treatment arms. Three studies investigated topical tranexamic acid; the other studies reported the use of intravenous tranexamic acid. For our primary outcome, surgical field bleeding score measured with the Boezaart or Wormald grading score, we pooled data from 13 studies. The pooled result demonstrated that tranexamic acid probably reduces the surgical field bleeding score, with a standardised mean difference (SMD) of -0.87 (95% confidence interval (CI) -1.23 to -0.51; 13 studies, 772 participants; moderate-certainty evidence). A SMD below -0.70 represents a large effect (in either direction). Tranexamic acid may result in a slight reduction in blood loss during surgery compared to placebo with a mean difference (MD) of -70.32 mL (95% CI -92.28 to -48.35 mL; 12 studies, 802 participants; low-certainty evidence). Tranexamic acid probably has little to no effect on the development of significant adverse events (seizures or thromboembolism) within 24 hours of surgery, with no events in either group and a risk difference (RD) of 0.00 (95% CI -0.02 to 0.02; 8 studies, 664 participants; moderate-certainty evidence). However, there were no studies reporting significant adverse event data with a longer duration of follow-up. Tranexamic acid probably results in little difference in the duration of surgery with a MD of -13.04 minutes (95% CI -19.27 to -6.81; 10 studies, 666 participants; moderate-certainty evidence). Tranexamic acid probably results in little to no difference in the incidence of incomplete surgery, with no events in either group and a RD of 0.00 (95% CI -0.09 to 0.09; 2 studies, 58 participants; moderate-certainty evidence) and likely results in little to no difference in surgical complications, again with no events in either group and a RD of 0.00 (95% CI -0.09 to 0.09; 2 studies, 58 participants; moderate-certainty evidence), although these numbers are too small to draw robust conclusions. Tranexamic acid may result in little to no difference in the likelihood of postoperative bleeding (placement of packing or revision surgery within three days of surgery) (RD -0.01, 95% CI -0.04 to 0.02; 6 studies, 404 participants; low-certainty evidence). There were no studies with longer follow-up.

There is moderate-certainty evidence to support the beneficial value of topical or intravenous tranexamic acid during endoscopic sinus surgery with respect to surgical field bleeding score. Low- to moderate-certainty evidence suggests a slight decrease in total blood loss during surgery and duration of surgery. Whilst there is moderate-certainty evidence that tranexamic acid does not lead to more immediate significant adverse events compared to placebo, there is no evidence regarding the risk of serious adverse events more than 24 hours after surgery. There is low-certainty evidence that tranexamic acid may not change postoperative bleeding. There is not enough evidence available to draw robust conclusions about incomplete surgery or surgical complications.