From the 2018 HVPAA National Conference
Tharakeswara Bathala (University of Texas MD Anderson Cancer Center), Richard Ogunti (Houston Methodist), Naveen Garg (University of Texas MD Anderson Cancer Center), Egbert Pravinkumar (University of Texas MD Anderson Cancer Center), Deepak Bedi (University of Texas MD Anderson Cancer Center)
Background
The actual incidence of upper extremity deep venous thrombosis in the oncology care setting, the profile of patients at increased risk for the development of upper extremity deep vein thrombosis, and the clinical sequelae of this condition, particularly with regards to the development of recurrent venous thromboembolic events, remains unclear.
Objectives
To test the hypothesis that upper extremity and subclavian deep venous thrombosis (UEDVT) always develops in patients with local predisposing risk factors and to study their association with overall mortality.
Methods
Venous duplex Doppler ultrasound studies of the upper extremity (n=600) in 523 consecutive patients in a major tertiary cancer center, over a 24-month period, were retrospectively reviewed for presence of thrombus and predisposing risk factors (central venous line in place or removed within 30 days prior, chemotherapy within 30 days, regional surgery or radiation therapy), incidence of pulmonary embolus and overall mortality.
Results
DVT was diagnosed sonographically in 196 of 600 (32.7%) studies.Central lines were present in 338 of 600 studies, and 167 of these (49%) were associated with DVT. Thrombosis was related to the presence of a central line in the prior 30 days in 167 of 196 studies (85.2%). Of the remaining DVT positive studies, 3% had a central line removed between 30 days and 1-year prior, a contralateral central line (4%), adjacent lymphadenopathy or surgery (3%), radiation therapy (3%), other pathology (2%). Only one study showed no related causes. The odds of developing a catheter-related thrombus (within 30 days) were significantly higher versus non-catheter related thrombus (OR=8.091, 95% CI= 5.1785-12.644, p value=0.000). The risk of DVT in studies with a central line and chemotherapy within 30 days was 1.567 (significant, p value=0.047) compared to the central line but no chemotherapy. However, chemotherapy alone, without the presence of a catheter, did not confer a significant risk of developing DVT (odds ratio = 1.027, p value=0.948). Pulmonary embolus occurred in 11 patients, only 5 of these had DVT, and four were catheter-related, all subclavian in location.
Overall mortality 15 months after the ultrasound study was not significantly different in patients with DVT compared to no DVT. However, non-catheter related DVT conferred a more than four times risk of death compared to catheter-related DVT (OR=4.2339, p value=0.001)
Conclusion
Central venous lines, and occasionally other regional causes such as radiation, surgery or tumor mass are the strongest predictors of a positive ultrasound study for UEDVT. Unlike lower extremity, UEDVT almost never occurs without a local cause.
Implications for the Patient
Targeted clinical decision support system built into ordering system (RIS) for upper extremity venous Doppler study that identifies predisposing risk factors before processing study order may be justified to promote appropriate use criteria and avoid overutilization.