Drugs to reduce bleeding and transfusion in adults undergoing cardiac surgery: a systematic review and network meta-analysis

Tranexamic Acid as a Preventive Strategy Against Periprosthetic Joint Infection in Aseptic Revision Arthroplasty: A Comprehensive Review

Periprosthetic joint infection (PJI) is a severe complication following joint replacement surgeries, particularly in aseptic revision arthroplasty, where infection rates are higher compared to primary procedures. The extended surgical time, increased blood loss, and the presence of scar tissue contribute to the higher susceptibility to PJI in revision surgeries. Tranexamic acid (TXA), a synthetic antifibrinolytic agent, is widely used in orthopaedic surgery to reduce intraoperative and postoperative bleeding. By stabilising blood clots and reducing the need for blood transfusions, TXA improves patient outcomes and reduces complications related to excessive bleeding. Emerging evidence suggests that TXA may also play a role in reducing PJI, as minimising bleeding and haematoma formation can reduce bacterial colonisation and blood transfusions are associated with increased infection risks due to immunomodulation. This review explores the potential of TXA as a preventive strategy against PJI in aseptic revision arthroplasty, evaluating its mechanisms, clinical applications, and current evidence. While TXA's efficacy in reducing blood loss is well-established, its role in infection prevention, particularly through indirect mechanisms such as limiting haematoma formation, warrants further investigation. By incorporating TXA into multimodal strategies aimed at reducing PJI, surgeons can potentially improve patient outcomes and reduce the financial burden on healthcare systems. This review provides a comprehensive examination of the available data on TXA's role in preventing PJI in revision arthroplasty, with an emphasis on understanding its mechanisms and identifying gaps in current knowledge that require further research.

Drugs to reduce bleeding and transfusion in major open vascular or endovascular surgery: a systematic review and network meta-analysis

BACKGROUND

Vascular surgery may be followed by internal bleeding due to inadequate surgical haemostasis, abnormal clotting, or surgical complications. Bleeding ranges from minor, with no transfusion requirement, to massive, requiring multiple blood product transfusions. There are a number of drugs, given systemically or applied locally, which may reduce the need for blood transfusion.

OBJECTIVES

To assess the effectiveness and safety of anti-fibrinolytic and haemostatic drugs and agents in reducing bleeding and the need for blood transfusion in people undergoing major vascular surgery or vascular procedures with a risk of moderate or severe (> 500 mL) blood loss.

SEARCH METHODS

We searched: Cochrane Central Register of Controlled Trials; MEDLINE; Embase; CINAHL, and Transfusion Evidence Library. We also searched the WHO ICTRP and ClinicalTrials.gov trial registries for ongoing and unpublished trials. Searches used a combination of MeSH and free text terms from database inception to 31 March 2022, without restriction on language or publication status.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in adults of drug treatments to reduce bleeding due to major vascular surgery or vascular procedures with a risk of moderate or severe blood loss, which used placebo, usual care or another drug regimen as control.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were units of red cells transfused and all-cause mortality. Our secondary outcomes included risk of receiving an allogeneic blood product, risk of reoperation or repeat procedure due to bleeding, risk of a thromboembolic event, risk of a serious adverse event and length of hospital stay. We used GRADE to assess certainty of evidence.

MAIN RESULTS

We included 22 RCTs with 3393 participants analysed, of which one RCT with 69 participants was reported only in abstract form, with no usable data. Seven RCTs evaluated systemic drug treatments (three aprotinin, two desmopressin, two tranexamic acid) and 15 RCTs evaluated topical drug treatments (drug-containing bioabsorbable dressings or glues), including fibrin, thrombin, collagen, gelatin, synthetic sealants and one investigational new agent. Most trials were conducted in high-income countries and the majority of the trials only included participants undergoing elective surgery. We also identified two ongoing RCTs. We were unable to perform the planned network meta-analysis due to the sparse reporting of outcomes relevant to this review. Systemic drug treatments We identified seven trials of three systemic drugs: aprotinin, desmopressin and tranexamic acid, all with placebo controls. The trials of aprotinin and desmopressin were small with very low-certainty evidence for all of our outcomes. Tranexamic acid versus placebo was the systemic drug comparison with the largest number of participants (2 trials; 1460 participants), both at low risk of bias. The largest of these included a total of 9535 individuals undergoing a number of different higher risk surgeries and reported limited information on the vascular subgroup (1399 participants). Neither trial reported the number of units of red cells transfused per participant up to 30 days. Three outcomes were associated with very low-certainty evidence due to the very wide confidence intervals (CIs) resulting from small study sizes and low number of events. These were: all-cause mortality up to 30 days; number of participants requiring an allogeneic blood transfusion up to 30 days; and risk of requiring a repeat procedure or operation due to bleeding. Tranexamic acid may have no effect on the risk of thromboembolic events up to 30 days (risk ratio (RR) 1.10, 95% CI 0.88 to 1.36; 1 trial, 1360 participants; low-certainty evidence due to imprecision). There is one large ongoing trial (8320 participants) comparing tranexamic acid versus placebo in people undergoing non-cardiac surgery who are at high risk of requiring a red cell transfusion. This aims to complete recruitment in April 2023. This trial has primary outcomes of proportion of participants transfused with red blood cells and incidence of venous thromboembolism (DVT or PE). Topical drug treatments Most trials of topical drug treatments were at high risk of bias due to their open-label design (compared with usual care, or liquids were compared with sponges). All of the trials were small, most were very small, and few reported clinically relevant outcomes in the postoperative period. Fibrin sealant versus usual care was the topical drug comparison with the largest number of participants (5 trials, 784 participants). The five trials that compared fibrin sealant with usual care were all at high risk of bias, due to the open-label trial design with no measures put in place to minimise reporting bias. All of the trials were funded by pharmaceutical companies. None of the five trials reported the number of red cells transfused per participant up to 30 days or the number of participants requiring an allogeneic blood transfusion up to 30 days. The other three outcomes were associated with very low-certainty evidence with wide confidence intervals due to small sample sizes and the low number of events, these were: all-cause mortality up to 30 days; risk of requiring a repeat procedure due to bleeding; and risk of thromboembolic disease up to 30 days. We identified one large trial (500 participants) comparing fibrin sealant versus usual care in participants undergoing abdominal aortic aneurysm repair, which has not yet started recruitment. This trial lists death due to arterial disease and reintervention rates as primary outcomes.

AUTHORS' CONCLUSIONS

Because of a lack of data, we are uncertain whether any systemic or topical treatments used to reduce bleeding due to major vascular surgery have an effect on: all-cause mortality up to 30 days; risk of requiring a repeat procedure or operation due to bleeding; number of red cells transfused per participant up to 30 days or the number of participants requiring an allogeneic blood transfusion up to 30 days. There may be no effect of tranexamic acid on the risk of thromboembolic events up to 30 days, this is important as there has been concern that this risk may be increased. Trials with sample size targets of thousands of participants and clinically relevant outcomes are needed, and we look forward to seeing the results of the ongoing trials in the future.

Real-World Clinical and Economic Outcomes Associated with Surgiflo® vs Floseal in Cardiovascular Surgeries in the US

Background

Topical hemostatic agents are an option for controlling bleeding during cardiovascular surgery. Previous studies comparing topical hemostatic agents in cardiovascular surgery predate the 2012 reformulation of Surgiflo®, which had been re-engineered to increase paste viscosity and thus be more adherent to the bleeding surface.

Objective

To compare clinical and economic outcomes in patients receiving the current formulation of Surgiflo vs Floseal during cardiovascular surgeries.

Methodology

A retrospective analysis was conducted using the Premier Healthcare Database. Eligible patients had an inpatient cardiovascular surgery between 1/1/2013 and 6/1/2018, were ≥18 years old and received the current formulation of Surgiflo or Floseal during surgery. Propensity score matching was performed, with exact matching on the surgery year and surgery type (aortic, coronary artery bypass grafting, valve, or other). Descriptive analysis and generalized estimating equations models compared outcomes between the Surgiflo and Floseal groups.

Results

The matched sample included 5768 patients in each group (mean age: 66.5 years; 66.3% male). In the matched sample, rates of any documented bleeding event were similar in Surgiflo and Floseal groups (6.9% vs 7.2%; P = 0.576). Differences in transfusion rates between patients receiving Surgiflo vs Floseal varied by operational definition and timing of measurement but did not differ by >2 percentage points. Compared to Floseal, patients who received Surgiflo experienced longer surgery duration (306.0 vs 299.4 minutes), lower hospitalization cost ($44,146 vs $46,812), and lower odds of readmission at 30, 60, and 90 days post-discharge (all P < 0.05). Inpatient mortality and LOS were comparable between Surgiflo and Floseal (all P > 0.05).

Conclusion

In this large study of real-world clinical and economic outcomes after cardiovascular surgery involving the current formulation of Surgiflo vs Floseal, Surgiflo was associated with mostly similar clinical outcomes as compared with Floseal. Differences in selected economic/resource use outcomes were also observed, for which root-cause analysis in future research would be informative.