Intraoperative heparin use is associated with reduced mortality without increasing hemorrhagic complications after thoracic endovascular aortic repair for blunt aortic injury

Abstract

Objective: Thoracic endovascular aortic repair (TEVAR) is an effective treatment of blunt thoracic aortic injury (BTAI). However, the risks and benefits of administering intraoperative heparin in trauma patients are not well-defined, especially with regard to bleeding complications.

Methods: The Vascular Quality Initiative registry was queried from 2013 to 2019 to identify patients who had undergone TEVAR for BTAI with or without the administration of intraoperative heparin. Univariate analyses were performed with the Student t test, Fisher exact test, or χ² test, as appropriate. Multivariable logistic regression was then performed to assess the association of heparin with inpatient mortality.

Results: A total of 655 patients were included, of whom most had presented with grade III (53.3%) or IV (20%) BTAI. Patients receiving heparin were less likely to have an injury severity score (ISS) of ≥15 (70.2% vs 90.5%; P < .0001) or major head or neck injury (39.6% vs 62.9%; P < .0001). Patients receiving heparin also had a lower incidence of inpatient death (5.1% vs 12.9%; P < .01). Across all injury grades, heparin use was not associated with the need for intraoperative transfusion or postoperative transfusion or the development of hematoma. In patients with grade III BTAI, the nonuse of heparin was associated with an increased risk of lower extremity embolization events (7.4% vs 1.8%; P < .05). On multivariable logistic regression analysis for inpatient mortality, intraoperative heparin use (odds ratio [OR], 0.31; 95% confidence interval [CI], 0.11-0.86; P < .05) and female gender (OR, 0.11; 95% CI, 0.11-0.86; P < .05) were associated with better survival, even after controlling for head and neck trauma and injury grade. In contrast, increased age (OR, 1.06; 95% CI, 1.03-1.1; P < .001), postoperative transfusion (OR, 1.06; 95% CI, 1.02-1.11; P < .01), higher ISS (OR, 1.04; 95% CI, 1.01-1.07; P < .05), postoperative dysrhythmia (OR, 4.48; 95% CI, 1.10-18.18; P < .05), and postoperative stroke or transient ischemic attack (OR, 5.54; 95% CI, 1.11-27.67; P < .05) were associated with increased odds of inpatient mortality.

Conclusions: Intraoperative heparin use was associated with reduced inpatient mortality for patients undergoing TEVAR for BTAI, including those with major head or neck trauma and high ISSs. Heparin use did not increase the risk of hemorrhagic complications across all injury grades. Also, in patients with grade III BTAI, heparin use was associated with a reduced risk of lower extremity embolic events. Heparin appears to be safe during TEVAR for BTAI and should be administered when no specific contraindication exists.

Keywords: Blunt traumatic aortic injury; Heparin; Thoracic aorta; Thoracic endovascular aortic repair; Vascular trauma.