Effectiveness of Tranexamic Acid Administration on Intraoperative Blood Loss in Elective Craniofacial Surgery

Abstract: The purpose of this study was to determine if intraoperative use of tranexamic acid (TXA) was associated with estimated blood loss in patients who underwent elective craniofacial surgery.

Introduction: Intraoperative blood loss has been shown to significantly contribute to postoperative morbidity and mortality in patients undergoing surgical procedures. It is the responsibility of the anesthesia clinician to accurately assess and actively replace ongoing blood loss, as well as employ strategies to curtail perioperative hemorrhage. While numerous methods exist to minimize surgical blood loss, such as mild hypothermia and controlled hypotensive techniques, these interventions can prove hazardous in pediatric patients and those with multi-morbidities. Additionally, allogenic blood transfusions possess unique risks in the form of transmissible disease and transfusion complications. It is imperative that the safest, scientifically-proven, most cost-effective, methods be adopted into clinical practice. This will help to ensure optimization of surgical outcomes, reduction in health care costs, and promotion of patients along the wellness continuum. Therefore, antifibrinolytic therapy is being utilized to aid in the reduction of perioperative blood loss. The more recent use of perioperative Tranexamic Acid to decrease surgical blood loss has assisted in achievement of these goals. The findings of this study could be directly applied to patients undergoing elective craniofacial surgery at CAMC and other facilities world-wide. The Certified Registered Nurse Anesthetist (CRNA) will be able to safely implement the results of this evidenced based research into daily practice.

Methodology: A retrospective, quantitative, cohort study design was utilized for this research. A systematic chart review was completed of patients age three months – 35 years old, American Society of Anesthesiologist (ASA) physical classification I-III, who underwent elective craniofacial surgery between June 1, 2008 and June 1, 2018. A total of 108 patients were included in the study and were classified into two groups: Group 1 was comprised of 54 patients who did not receive intraoperative TXA; Group 2 consisted of 54 patients who did receive intraoperative TXA. Primary independent variables were administration of TXA or no administration of TXA. Additional independent variables included age, gender, body mass index (BMI), and ASA physical status. The dependent variables were estimated blood loss and the need for intraoperative blood transfusion. The hypotheses of this study were that intraoperative administration of TXA in patients who underwent elective craniofacial surgery would be associated with decreased estimated surgical blood loss and a decreased need for blood transfusion throughout the operative period versus patients who did not receive intraoperative TXA.

Results: The patient population for this study consisted of 108 patients classified into Group 1 (54 patients who did not receive intraoperative TXA) and Group 2 (54 patients who did receive TXA intraoperatively). Mean age of patients was 9.81 ± 9.06 years. Average BMI was 21.73 ± 6.28 kg/m2. Average estimated blood loss, expressed as percentage of EBV, was 13.80 ± 14.71%. No statistical differences were found between the two groups in regard to age and BMI (p = 0.962 and 0.410, respectively). Additionally, there was no statistical significance between Group 1 and 2 in gender and ASA classification (p =0.700 and 0.701, respectively). Step-wise regression showed no statistically significant relationship existed between TXA administration, transfusion requirements, and estimated blood loss. However, step-wise regression results indicated a significant association between age and estimated blood loss. Logistic regression analysis revealed a significant association between age and blood transfusion (p = .000). Gender, ASA classification, and TXA administration were not significantly associated with intraoperative blood transfusion. As age increased patients were less likely to receive intraoperative blood transfusion (p = .021).

Discussion: The results of this study did not support the hypotheses that intraoperative administration of TXA in patients who underwent elective craniofacial surgery would be associated with decreased estimated surgical blood loss and a decreased need for blood transfusion throughout the operative period versus patients who did not receive intraoperative TXA. Since intraoperative administration of TXA was not significantly associated with decrease in blood loss or need for intraoperative blood transfusion, the hypotheses were rejected.

Conclusion: The intraoperative administration of TXA was not associated with decreased estimated surgical blood loss or decreased need for intraoperative blood transfusion in patients who underwent elective craniofacial surgery. The results of this retrospective, cohort study concluded that increasing patient age was associated with both decreased likelihood for blood transfusion as well as decreased estimated blood loss.