A national field study of quality assessment of CoaguChek point-of-care testing prothrombin time monitors

Drive-Through Model for Anticoagulation Clinics During the COVID-19 Pandemic

The coronavirus disease of 2019 (COVID-19) has posed a major challenge for providers and patients. A large number of patients with atrial fibrillation, venous thromboembolism, or valvular heart disease are chronically anticoagulated with vitamin K antagonists and rely on frequent follow ups at anticoagulation clinics for management of their anticoagulation therapy. The need for isolation during COVID-19 pandemic can potentially limit access to health care including anticoagulation clinics and directly affect the care of patients on chronic anticoagulation. Therefore, we created a drive-through clinic to bridge the gap of continuation of care and preservation of social distancing precautions. In this manuscript, we report the steps in implementing such initiative which can be applied to other clinics during a pandemic.

Point of care coagulometry in prehospital emergency care: an observational study

Background

Haemostatic impairment can have a crucial impact on the outcome of emergency patients, especially in cases of concomitant antithrombotic drug treatment. In this prospective observational study we used a point of care (POC) coagulometer in a prehospital physician-based emergency medical system in order to test its validity and potential value in the treatment of emergency patients.

Methods

During a study period of 12 months, patients could be included if venous access was mandatory for further treatment. The POC device CoaguChek® was used to assess international normalized ratio (INR) after ambulance arrival at the scene. Results were compared with in-hospital central laboratory assessment of INR. The gain of time was analysed as well as the potential value of POC testing through a questionnaire completed by the responsible prehospital emergency physician.

Results

A total of 103 patients were included in this study. POC INR results were highly correlated with results of conventional assessment of INR (Bland-Altman-bias: 0.014). Using a cutoff value of INR >1.3, the device’s sensitivity to detect coagulopathy was 100 % with a specificity of 98.7 %. The median gain of time was 69 min. Treating emergency physicians considered the value of prehospital POC INR testing ‘high’ in 9 % and ‘medium’ in 21 % of all patients. In patients with tracer diagnosis ‘neurology’, the value of prehospital INR assessment was considered ‘high’ or ‘medium’ (63 %) significantly more often than in patients with non-neurological tracer diagnoses (24 %).

Conclusions

Assessment of INR through a POC coagulometer is feasible in prehospital emergency care and provides valuable information on haemostatic parameters in patients. Questionnaire results suggest that POC INR testing may present a valuable technique in selected patients. Whether this information translates into an improved management of respective patients has to be evaluated in further studies.

Comparison of prothrombin time derived from CoaguChek XS and laboratory test according to fibrinogen level

Background

CoaguChek XS is one of the most widely used point‐of‐care (POC) devices to evaluate prothrombin time for monitoring oral anticoagulant therapy. Unlike laboratory methods, it detects electrical signals produced by thrombin activity to derive the international normalized ratio (INR). Therefore, we hypothesized that laboratory methods and CoaguChek XS could produce different results according to fibrinogen level.

Methods

We compared INR values obtained from the CoaguChek XS and conventional laboratory method with 91 plasma samples covering a wide range of fibrinogen levels.

Results

The samples were stratified into low, mid, and high fibrinogen groups by fibrinogen levels of <130 mg/dl, 130–450 mg/dl, and >450 mg/dl, respectively. The mean INR difference of the low fibrinogen group was significantly different from that of the mid or high fibrinogen group (P < 0.001). In the low fibrinogen group, CoaguChek XS INR showed a negative bias compared with the laboratory INR, while the mid and high fibrinogen groups had positive bias.

Conclusion

Our results suggest that patient selection according to fibrinogen status should precede the implementation of POC testing using CoaguChek XS. Also, periodic comparisons between CoaguChek XS and laboratory INR results should be continued during the use of CoaguChek XS.