Perioperative and Postoperative Blood Loss

Dear Readers:   Perioperative and postoperative blood loss can be a serious medical problem, increasing the need for blood transfusions, reducing quality of patient outcomes and increasing health care costs. Clinical options to reduce risk factors for perioperative blood loss or transfusions include preoperatively normalizing patient hemoglobin and blood pressure, reducing the duration of surgery¹ or modifying surgical technique.² Physical postoperative interventions, such as flexion and/or compression do not seem to reduce blood loss after total knee arthroplasty.³ Systemic⁴ or topical⁵ antifibrinolytic agents limit perioperative bleeding and transfusions in patients undergoing either on-pump or off-pump cardiovascular bypass graft surgery. Similar research suggests efficacy of the antifibrinolytic agent tranexamic acid (TXA) in improving the view of the surgical field while reducing blood loss and transfusions during operations as diverse as spinal,⁶ oral,⁷ or endoscopic sinus⁸ surgery. Two studies reviewed below explore TXA efficacy in limiting bleeding when applied topically during total knee arthroplasty or administered intravenously during Cesarean section surgery. Laura Bolton, PhD, FAPWCA Adjunct Associate Professor Department of Surgery, UMDNJ WOUNDS Editorial Advisory Board Member and Department Editor

Total Knee Arthroplasty

Reference: Wong J, Abrishami A, El Beheiry H, et al. Topical application of tranexamic acid reduces postoperative blood loss in total knee arthroplasty: a randomized, controlled trial. J Bone Joint Surg Am. 2010;92(15):2503–2513. Rationale: Tranexamic acid (TXA) topical application to bleeding wound surfaces reduces blood loss in patients undergoing some major surgeries without systemic complications. Objective: Assess safety and efficacy of postoperative topical TXA on reducing subsequent blood loss in patients undergoing primary unilateral total knee arthroplasty with cement. Methods: In a prospective, double-blind, randomized, controlled trial (RCT), total knee arthroplasty patients were given topical 1.5 g (n = 31) or 3.0 g (n = 34) of TXA in 100 mL of normal saline solution or equal volume of placebo (n = 35). All solutions were placed into the operated joint for five minutes at the end of surgery. The primary outcome was estimated blood loss, which was calculated as (preoperative hemoglobin) – (lowest postoperative hemoglobin). Secondary outcomes were number of perioperative blood transfusions, number of blood units transfused, surgical infection rate, length of hospital stay, time until start of rehabilitation, postoperative changes in joint range of motion and severity of pain measured using a visual analog scale on postoperative day 2, and Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) score 6 weeks after surgery. Plasma TXA level was measured with a tandem mass spectrometer 1 hour after tourniquet release. Criterion for transfusion was a hemoglobin level of Results: Groups were comparable at baseline on all variables measured. Both TXA groups had higher postoperative hemoglobin and less calculated total blood loss than the placebo group (P Authors’ Conclusions: Applying TXA directly into total knee arthroplasty surgical sites reduced postoperative bleeding 300 mL–400 mL (20%–25%) resulting in TXA group hemoglobin levels 16%–17% higher than those of patients receiving placebo. There was no significant or clinically important increase in complications of the TXA groups.

Cesarean Sections

Reference: Güngördük K, Yıldırım G, Asıcıoğlu O, Güngördük OC, Sudolmus S, Ark C. Efficacy of intravenous tranexamic acid in reducing blood loss after elective Cesarean section: a prospective, randomized, double-blind, placebo-controlled study. Am J Perinatol. 2010. [Epub ahead of print]. Rationale: Systemic TXA safely and effectively reduces perioperative blood loss in a variety of surgeries, but has not been tested in elective Cesarean sections (CS). Objective: Determine efficacy and safety of intravenous TXA in reducing blood loss during elective CS. Methods: A prospective double-blind RCT assigned 330 women undergoing elective CS to receive a pre-operative intravenous infusion of 1 g TXA/10 mL added to 20 mL of 5% glucose or placebo (30 mL 5% glucose). The primary outcome measure was estimated blood loss following CS. Secondary measures included maternal and neonatal outcomes, need for added uterotonic agents and incidence of thromboembolic events. Results: Women receiving TXA had lower calculated blood loss than the placebo group (P 1 L (P Authors’ Conclusions: TXA is safe and effective in reducing bleeding associated with a CS.

Clinical Perspective

  Major advances have been made within the last 20 years to limit perioperative blood loss, which has clearly benefitted surgeons, patients, and healthcare systems. Pharmacologic intervention with antifibrinolytic agents such as TXA has reduced the need for transfusions by as much as 1 pint of blood per patient in longer operations (eg, cardiovascular bypass graft surgery). Recent research exploring topical antifibrinolytic agent application is designed to reduce the likelihood of side effects or allergic reactions to systemically administered antifibrinolytic agents.   Systemic or topical TXA appears to reduce perioperative blood loss without raising the risk of myocardial infarction, stroke, pulmonary embolism,⁴ postoperative deep vein thrombosis, or thromboembolism.⁶ Authors are quick to emphasize that larger samples are needed to confirm safety with respect to these rare, but clinically important events. While maintaining vigilance with regard to safety of antifibrinolytic agents, one may cautiously conclude that they offer significant advantages in preserving clear visibility of the surgical field while limiting blood loss and the resulting need for blood transfusions.

References

1. Durasek J, Dovzak-Bajs I, Sarić V. [Factors affecting blood loss in total knee arthroplasty patients]. Acta Med Croatica. 2010;64(3):209–214. [Article in Croatian]. 2. Du W, Ma B, Guo Y, Yang K. Microdebrider vs. electrocautery for tonsillectomy: a meta-analysis. Int J Pediatr Otorhinolaryngol. 2010;74(12):1379–1383. 3. Madarevic T, Tudor A, Sestan B, et al. Postoperative blood loss management in total knee arthroplasty: a comparison of four different methods. Knee Surg Sports Traumatol Arthrosc. 2010. [Epub ahead of print]. 4. Ma SC, Brindle W, Burton G, et al. Tranexamic acid is associated with less blood transfusion in off-pump coronary artery bypass graft surgery: A systematic review and meta-analysis. J Cardiothorac Vasc Anesth. 2010. [Epub ahead of print]. 5. Abrishami A, Chung F, Wong J. Topical application of antifibrinolytic drugs for on-pump cardiac surgery: a systematic review and meta-analysis. Can J Anaesth. 2009;56(3):202–212. 6. Liu J, Peng H, Shen J, Qiu G. [A meta-analysis of the effectiveness and safety of using tranexamic acid in spine surgery]. Zhonghua Wai Ke Za Zhi. 2010;48(12):937–942. [Article in Chinese]. 7. Madrid C, Sanz M. What influence do anticoagulants have on oral implant therapy? A systematic review. Clin Oral Implants Res. 2009;20(Suppl 4):96–106. 8. Athanasiadis T, Beule AG, Wormald PJ. Effects of topical antifibrinolytics in endoscopic sinus surgery: a pilot randomized controlled trial. Am J Rhinol. 2007;21(6):737–742.