Perioperative Coagulation Profile with Thromboelastography in Aspirin-Treated Patients Undergoing Posterior Lumbar Fusion.

Background: It has been generally recommended that platelet function may recover after the recommended 5-day discontinuation period prior to operation. The technique of thromboelastography has been demonstrated to monitor intraoperative platelet function in liver transplantation and coronary bypass surgery. However, there is a dearth of literature that addresses the utility of thromboelastography in aspirin-treated patients undergoing fusion.

Objectives: To introduce a functional method of monitoring coagulation and validate the effectiveness of thromboelastography perioperatively in assessing aspirin-treated patients undergoing posterior lumbar fusion.

Study Design: This research used a retrospective study design.

Setting: Orthopedic Department of Changhai Hospital,Shanghai, China and Orthopedic and Anesthesia Department of Changzheng Hospital.

Methods: Eighty patients were divided into aspirin-naive and aspirin-treated groups in this study. They had equally undergone lumbar fusion surgery for at least one or more segments between January and June 2018. They matched for age, gender, number of fused segments, and surgical procedures. The coagulation profile, including the reaction time (R), kinetics (K), maximal amplitude (MA), alpha-angle, and coagulation index (CI), platelet inhibition ratio (PIR) was analyzed by thromboelastogram (TEG) prior to operation and on preoperative days 1, 3, and 5. Correlation analysis included parameters such as waiting time, intraoperative blood loss, and postoperative drainage.

Results: Perioperatively, the TEG values including R, K, MA, alpha-angle, and CI, PIR, and correlation analysis showed no significant difference between the 2 groups, respectively (P > 0.05).

Limitations: First, the relatively small number of patients recruited limits control over other factors; larger studies may need to confirm our findings. Second, the patients were objectively less healthy with more medication treatment, which may result in a variance in the amount of blood loss. Randomized controlled studies are needed to further confirm these results.

Conclusions: TEG may be a helpful method to monitor perioperative platelet function in aspirin-treated patients undergoing fusion. It may be comparatively safe to relax the restriction of the aspirin-discontinued therapeutic window to approximately 2 to 3 days prior to surgery.