Common alternative diagnoses in general practice when deep venous thrombosis is excluded.

BACKGROUND: In patients initially suspected of deep venous thrombosis (DVT) the diagnosis can be confirmed in approximately 10 to 30% of cases. For the majority of patients this means that eventually an alternative diagnosis is assigned. OBJECTIVE: To assess the frequency distribution of alternative diagnoses and subsequent management of patients in primary care after initial exclusion of DVT. In addition, assess the value of ultrasound examination for the allocation of alternative diagnoses. METHODS: Data were recorded by general practitioners alongside a diagnostic study in primary care in the Netherlands (AMUSE). Additional data were retrieved from a three-month follow-up questionnaire. A descriptive analysis was performed using these combined data. RESULTS: The most prevalent diagnoses were muscle rupture (18.5%), chronic venous insufficiency (CVI) (14.6%), erysipelas/cellulitis (12.6%) and superficial venous thrombosis (SVT) (10.9%). Alternative diagnoses were based mainly on physical examination; ultrasound examination (US) did not improve the diagnostic yield for the allocation of alternative diagnoses. In about 30% of all cases, a wait and see approach was used (27 to 41%). During the three-month follow-up nine patients were diagnosed with venous thromboembolic disease, three of which occurred in patients with the working diagnosis of SVT (p=0.026). CONCLUSIONS: We found that after exclusion of DVT in general practice a wait and see policy in the primary care setting is uneventful for almost one third of patients, but with the alternative diagnosis of SVT, patients may require closer surveillance since we found a significant association with thrombosis in these patients.

Cost-effectiveness of ruling out deep venous thrombosis in primary care versus care as usual.

BACKGROUND: Referral for ultrasound testing in all patients suspected of DVT is inefficient, because 80-90% have no DVT. OBJECTIVE: To assess the incremental cost-effectiveness of a diagnostic strategy to select patients at first presentation in primary care based on a point of care D-dimer test combined with a clinical decision rule (AMUSE strategy), compared with hospital-based strategies. PATIENTS/METHODS: A Markov-type cost-effectiveness model with a societal perspective and a 5-year time horizon was used to compare the AMUSE strategy with hospital-based strategies. Data were derived from the AMUSE study (2005-2007), the literature, and a direct survey of costs (2005-2007). RESULTS OF BASE-CASE ANALYSIS: Adherence to the AMUSE strategy on average results in savings of euro138 ($185) per patient at the expense of a very small health loss (0.002 QALYs) compared with the best hospital strategy. The iCER is euro55 753($74 848). The cost-effectiveness acceptability curves show that the AMUSE strategy has the highest probability of being cost-effective. RESULTS OF SENSITIVITY ANALYSIS: Results are sensitive to decreases in sensitivity of the diagnostic strategy, but are not sensitive to increase in age (range 30-80), the costs for health states, and events. CONCLUSION: A diagnostic management strategy based on a clinical decision rule and a point of care D-dimer assay to exclude DVT in primary care is not only safe, but also cost-effective as compared with hospital-based strategies.

Survey of the management of deep vein thrombosis in general practice in the Netherlands.

BACKGROUND: To investigate the management of (suspected) deep vein thrombosis in general practice. METHODS: Self completing postal questionnaire among a random sample of 692 general practitioners in the Netherlands. RESULTS: The overall response rate was 58%. Eighty-nine percent of the respondents initiated objective evaluation. Less than 3% usually make the diagnosis on clinical grounds only. Ninety-two percent initiated adequate treatment for the last patient with deep vein thrombosis. No more than 4% usually treat patients with acenocoumarol alone. Respondents frequently referred a patient to a specialist, 41% to confirm the diagnosis and 85% for treatment. Already 44% feel that management of deep vein thrombosis is a mandate of the general practitioner. For those who do not, the availability of diagnostic and therapeutic facilities are the main obstacles. CONCLUSION: In general practice objective diagnostic methods to evaluate suspected deep vein thrombosis are routinely used and patients receive adequate treatment. Although patients are frequently referred to the hospital many general practitioners feel that they should be able to take care of these patients themselves. (See Editorial p. 133)