Optimising VTE exclusion in general practice - Using capillary quantitative point-of-care D-dimer testing across various contexts
Jorn Heerink is a PhD student in the department Health Technology & Services Research. (Co)Promotors are prof.dr. G.C.M. Kusters and prof.dr.ir. H. Koffijberg from the faculty of Behavioural, Management and Social Sciences and dr. R. Oudega from Jeroen Bosch Hospital.
Cardiovascular fatalities are frequently attributed to venous thromboembolism (VTE), characterised by the development of blood clots in the deep veins of the legs (deep vein thrombosis or DVT) that may disseminate to the lungs. The diagnostic pathway often starts in general practice and involves a D-dimer test to rule out low-risk VTE. However, the current utilisation of this test presents several restrictions, including limited accessibility, extended waiting times, a high rate of false-positive results, and compatibility issues with the clinical context.
This PhD thesis aims to explore opportunities for optimising D-dimer testing in general practice, with a particular focus on near-patient point-of-care (POC) testing. Our research revealed that the current generation of POC D-dimer devices has evolved to the point where they can replace laboratory-based assays to adequately rule out VTE. Nevertheless, some devices still require improvement to enable reliable capillary whole blood finger stick measurements.
Other key findings include: i) D-dimer remains the preferred option for excluding clinically suspected VTE in general practice; ii) integrating D-dimer into the context of a DVT care pathway not only reduces the burden on patients and healthcare providers but also promotes adherence to the current guideline, acts as a filter to avoid unnecessary D-dimer tests, and ensures appropriate ultrasound follow-up for patients with high clinical decision rule (CDR) scores and/or elevated D-dimer results; iii) the realisation of significant benefits of implementing a CDR-based context in general practice, such as the CDR for VTE, hinges on the development and application of tailored CDRs that align with the unique primary care environment and anticipates recent developments; iv) introducing POC testing for DVT exclusion in general practice can result in substantial societal cost savings, while maintaining similar health outcomes compared to a laboratory-based approach.
In conclusion, given the performance, patient & user-friendliness and cost-effectiveness of the POC test systems studied, along with opportunities to further optimise the CDR for VTE, the author of this PhD thesis advocates for the integration of POC test-based approaches to D-dimer testing into the diagnostic algorithm for VTE exclusion in general practice.
