Role of POC INR in the early stage of diagnosis of coagulopathy

Abstract

Background: Acute bleeding requires fast and targeted therapy. Therefore, knowledge of the patient's potential to form a clot is crucial. Point-of-care testing (POCT) provides fast and reliable information on coagulation. Structural circumstances, such as person-bound sample transport, can prolong the reporting of the results. The aim of the present study was to investigate the diagnostic quality and accuracy between POCT INR diagnostics and standard laboratory analysis (SLA) as well as the time advantage between a pneumatic tube and a personal-based transport system.

Methods: Two groups of haemorrhagic patients (EG: emergency department; OG: delivery room; each n = 12) were examined in the context of bleeding emergencies using POCT and SLA. Samples were transported via a pneumatic tube system or by a personal transport service.

Results: INR results between POCT and SLA showed a high and significant correlation (EG: p < 0.001; OG: p < 0.001). POCT results were reported significantly more quickly (EG: 1.1 vs. 39.6 min; OG: 2.0 vs. 75.0 min; p < 0.001) and required less time for analysis (EG: 0.3 vs. 24.0 min; OG: 0.5 vs. 45.0 min; p < 0.001) compared to SLA. The time for transportation with the pneumatic tube was significantly shorter (8.0 vs. 18.5 min; p < 0.001) than with the personal-based transport system.

Conclusion: The results of the present study suggest that POCT may be a suitable method for the emergency diagnosis and may be used as prognostic diagnostic elements in haemotherapy algorithms to initiate targeted haemotherapy at an early point in time.

Keywords: Bleeding; INR; International normalized ratio; Point-of-care testing.

Fig. 1

INR results and correlationGroup dependent correlation of POCT results and standard laboratory analysis of INR. EG = Emergency Department group OG = Obstetric group X-axis: represents the results of POCT INR analysis. Y-axis: represents the results of conventional laboratory INR analysis.

Fig. 2

Bland-Altman plot. Analysis of differences between both measurement methods using a Bland-Altman plot. Mean of the differences as well as the lower (mean – 1.96 SD) and upper (mean + 1.96 SD) border are drawn. SD = standard deviation; CI = confidence interval; Bias = 0.082; SD = 0.191.

Fig. 3

Flowchart of analysed time intervals. T1 = Time interval between obtaining sample and POCT results are available (red) T2 = Time interval between obtaining sample and SL results are available (purple) T3 = Time needed for POCT measurements (green) T4 = Time needed for standard laboratory measurements (orange) T5 = Time needed for sample transportation (blue) PDS = pneumatic dispatch system; TS = personal based transport service; lab = laboratory; SL = standard laboratory; POCT = point of care testing; EG = emergency group (emergency department); OG = obstetric group.