1. Evidence Based and Cost Effective Guideline for DVT Triage
Moon Won, DO; Steven Connelly, MD
Greenville Health System
701 Grove Rd, Greenville, SC 29605
Introduction
The diagnostic approach for acute lower extremity DVT at GHS advises Doppler scans as the first line investigation for patients with a suspected lower extremity DVT. This approach is time consuming and costly with a low positive yield.
Strategies are needed to safely decrease the utilization of Doppler scans to control rising health care costs.
The diagnostic pathway recommended by ACCP and similarly by National Institute for Health and Care Excellence (NICE) presents a cost effective and safe guideline for clinicians to diagnose lower extremity DVT.
In patients who present with signs or symptoms of LE DVT (edema and/or erythema and/or tenderness), the initial diagnostic test should be guided by the clinical assessment of pretest probability by utilizing the Well’s score for DVT.
In patients with a low or moderate pretest probability (Well’s score of -2 to 2), a highly sensitive D-dimer test should be the initial test rather than a Duplex Doppler study. In patients with a high pretest probability (Well’s score of ≥3), a Duplex Doppler study should be the initial test.
Method
Reviewed charts of 68 patients with the diagnosis of lower extremity pain and/or edema and/or swelling who had a unilateral or bilateral lower extremity Doppler scan performed during their hospitalization at GMH between 10/2014 to 9/2015.
Patients were categorized into groups of low (Well’s score of -2 to 0), moderate (Well’s score of 1 to 2), or high risk (Well’s score of ≥3) for a lower extremity DVT by utilizing the Well’s score for DVT.
The total number of bilateral and unilateral Doppler scans obtained in the low and moderate groups were acquired and the total cost was estimated using the Healthcare Bluebook. This cost was compared to the cost of using d-dimer as the initial test in these two groups.
Other data such as number of Well’s score documented, number of d-dimers obtained, number of patients on chronic anti-coagulation were also obtained.
Excluded patients in the outpatient setting, surgical patients, pediatric patients, patients with suspected PE, and patients with suspected upper extremity DVT.
Results
Acknowledgments
Dr. Steven Connelly
Beverly Ross
Sally Nicholson
American College of Chest Physicians
National Institute for Health and Care Excellence
Conclusion
The diagnostic pathway recommended by American College of Chest Physicians (ACCP) and similarly by the NICE presents a cost effective, safe, and easy-to-use guideline for clinicians to approach suspected lower extremity DVT.
In patients who present with a possible lower extremity DVT (unilateral or bilateral lower extremity edema and/or erythema and/or tenderness), the initial diagnostic test should be guided by the clinical assessment of pretest probability by utilizing the Well’s score for DVT.
In patients with a low or moderate pretest probability (Well’s score of -2 to 2), a D-dimer test should be the initial test rather than a Duplex Doppler study. In these patients, if the D-dimer is negative, no further testing is recommended. If the D-dimer is positive, a Doppler study is then recommended. In patients with a high pretest probability (Well’s score of ≥3), a Duplex Doppler study should be the initial test.
If all patients at GMH who were categorized into low and moderate risk groups had a D-dimer level drawn initially instead of a Duplex Doppler study, a total of $25,506 would have been saved between 10/2014 to 9/2015.
Extrapolating the data from the study to the entire Greenville Health System (in-patient only), potentially, a total of $78,262 would have been saved if a D-dimer was the initial study performed in patients who had low to moderate pretest probability.
Number of patients categorized into low, moderate, or high risk for acute LE DVT using the Well’s score to determine the pretest probability.
Only 2 out of 59 patients in the low to moderate risk groups were positive for an acute LE DVT.
Aim
The objective was to analyze the cost-effectiveness of the current approach to diagnosing lower extremity DVT at GHS and to consider a more cost conscious model to approaching a suspected lower extremity DVT.
Results
Total cost of Doppler scans in the low to moderate risk groups compared to the much lower total cost of if a d-dimer was appropriately used as the initial test. Total potentially saved at GMH if d-dimer was the initial test in these groups and extrapolating to the entire GHS, total potentially saved at GHS between 10/2014 to 9/2015.
Cost of D-dimer $27, Unilateral LE Doppler $339, Bilateral LE Doppler $508