Background: There is a high incidence of venous thromboembolism (VTE) after lung resection, so it is necessary to identify the risk factors for VTE in these patients. It is also important to evaluate whether the modified Caprini score can accurately assess the risk of VTE in patients after lung resection.Methods: This retrospective study included 437 patients undergoing lung resection between July 2016 and December 2017. All patients underwent lower extremities ultrasound before and after operation to determine the presence of the newly diagnosed VTE. Results: Forty-seven (10.8%) of the 437 patients were diagnosed with VTE after lung surgery. Multivariate logistic regression analysis showed that age (OR, 2.04; 95% CI, 1.40-2.99), duration of operation (OR, 1.51; 95% CI, 1.08-2.12), lymphocyte count (OR, 0.28; 95% CI, 0.11-0.69), and D-dimer concentration (OR, 1.55; 95% CI, 1.22-1.97) were significantly associated with VTE in lung resection patients. The cut-off values for lymphocyte count and D-dimer concentration determined using receiver operating characteristic (ROC) curve were 1.15×10 9 /L and 1.37 μg/mL respectively. The modified Caprini score divided the patients into three groups: low risk (0-4 points), moderate risk (5-8 points) and high risk (≥9 points), and the incidence of VTE was 12.3% (37/300), 7.5% (10/133) and 0% (0/4), respectively (P>0.05). Conclusions: In this study, we identified four independent factors for VTE after lung resection patients: age, duration of operation, lymphocyte count, and D-dimer. According to the modified Caprini score, there were fewer patients in the high-risk group, and the incidence of VTE not increased with the increase of risk. Better evaluation of operation time and D-dimer may help the modified Caprini score to better assess VTE risk in these patients.

Background Venous thromboembolism (VTE) occurs at a high rate after lung cancer surgery and can be attributed to various clinical risk factors. Here, we aimed to determine whether early detection of perioperative D‐dimer and risk‐stratified cutoff values would improve the diagnostic efficacy of VTE. Methods In this case‐control study, D‐dimer results were acquired from 171 non‐small cell lung cancer (NSCLC) patients preoperatively and at the first, third, and fifth day after surgery. VTE was confirmed by Doppler ultrasonography and computer tomography pulmonary angiography (CTPA). Repeated measures ANOVA was used to analyze how D‐dimer changed with time and the effects of risk factors on D‐dimer levels. We then compared sensitivity, specificity and negative predictive value, using both adjusted and unadjusted cutoff values. Results VTE occurred in 23 patients (13.5%) of the study population. D‐dimer levels increased unsustainably after lung cancer surgery (P < 0.001) due to a trough on the third day, and patients who had undergone thoracotomy (P < 0.001) and those at a more advanced tumor stage (P = 0.037) had higher D‐dimer levels. Area under the curve of D‐dimer was greatest on the third day (0.762 [P < 0.001, 95% CI: 0.643–0.882]). Applying stratified cutoff values improved the specificity in the video‐assisted thoracoscopy surgery (VATS) (P = 0.004) and thoracotomy groups (P < 0.001). Conclusions D‐dimer levels elevated with fluctuation in NSCLC patients after surgery. Surgical options and tumor stages had an impact on D‐dimer levels. With regard to VTE diagnosis, stratified cutoff values by these two factors showed better accuracy compared with a collective one.. Key points Significant findings of the study The changing pattern of perioperative D‐dimer levels in NSCLC patients who received surgical therapy in a major teaching hospital in Beijing, China was revealed. What this study adds Risk‐stratified D‐dimer cutoff values adjusted to surgical methods and disease stages would benefit the exclusion of postoperative venous thromboembolism.

Background and Objectives: Lung cancer patients slated for surgery are at high risk of venous thromboembolism (VTE). Precise risk assessment is necessary for providing proper thromboprophylaxis and reducing morbidity and mortality of VTE.Methods: A multicenter, observational, cross-sectional cohort study, involving patients with primary lung cancer undergoing surgery, was carried out from August 2016 to December 2019. All patients were assessed according to the Caprini risk assessment model (RAM) and a modified scoring system incorporating elevated Ddimer and new stratification of surgical time. The endpoint was confirmed VTE or patient discharge.Results: Out of 1205 patients, 87 (7.2%) were diagnosed with VTE. The area under the curve of modified scores for VTE was 0.759, which was larger than that of the original one (0.589) (p < 0.05). By modified Caprini scoring system, a higher score was associated with increased VTE risk (odds ratio [OR], 1.345; 95% confidence interval [CI],; p < 0.001), and there was an increased OR of 4.090 (95% CI, 2.472-6.768, p < 0.001) for VTE in high-risk category patients. Conclusion:Modified Caprini RAM showed an improved prediction of high-risk patients with an elevated likelihood of postoperative VTE compared to the original one.