ABSTRACT
Objective To investigate the role of circulating neutrophil extracellular trap (NET) levels in the postoperative formation of deep vein thrombosis (DVT) in patients undergoing total knee arthroplasty (TKA). Methods Circulating NET levels were measured preoperatively and on postoperative days 1, 3, and 7 in 30 patients diagnosed with DVT by venography after TKA and 30 controls from May 2014 to July 2015. Results In patients with DVT, the mean circulating NET levels were significantly higher on postoperative days 1 and 3 compared with those in the non?DVT group (postoperative day 1, 1.598 ± 0.067 vs. 1.212 ± 0.037, t=7.514, P=0.000;postoperative day 3, 1.305±0.044 vs. 1.167±0.032, t=2.675, P=0.015). ROC curve analysis revealed the inferior sensitivity and specificity of NET levels on postoperative day 3 compared with postoperative day 1. Area under the curve (AUC) postoperative day 1 was 0.828 (95%CI:0.722, 0.933, P=0.000);AUC postoperative day 3 was 0.677 (95%CI:0.541, 0.814, P=0.018). The cutoff point for NET levels on postoperative day 1 was 1.294, with a sensitivity of 80%, a specificity of 80%, a posi?tive predictive value of 80%, and a negative predictive value of 80%. After Logistic regression, the NET level on postoperative day 1 was considered an independent predictor of DVT (OR:24.08, 95%CI:4.94, 117.28, P=0.000). Conclusion High circulating NET levels are associated with DVT in patients who undergo TKA. NETs may serve as a potential biological marker to delineate patients undergoing TKA who are most at risk for DVT.