TY - JOUR
T1 - International normalized ratio measurement during perioperative anticoagulation bridging with low-molecular-weight heparin in patients undergoing heart valve replacement surgery
AU - Rijvers, Liza
AU - Rijpma, Sanna R.
AU - van Wetten, Herbert B.
AU - Henskens, Yvonne M.C.
AU - Stroobants, An K.
N1 - Funding Information:
Materials were selected and prepared by Liesbeth Peels from the Radboud UMC. Measurements were performed by laboratory technicians of the Radboud UMC and Maastricht UMC under supervision of Annette Vendel (Werfen and Stago assays RadboudUMC), Nicole Butters (Roche assay RadboudUMC), and Dave Hellenbrand (Siemens assays MaastrichtUMC). The Coaguchek Pro II was a demo system temporarily provided by Roche Diagnostics, and the Hepzyme used was kindly provided by Siemens. This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. L.R. analyzed and interpreted data and wrote the manuscript. S.R. interpreted the data and edited the manuscript. H.W. pointed out the clinical problem and included patients for the study. Y.H. facilitated measurements in the MUMC and edited the manuscript. A.S. designed the study, interpreted the data, and edited the manuscript. All authors have approved the final manuscript. There are no competing interests to disclose.
Publisher Copyright:
© 2024 The Authors
PY - 2024/11/1
Y1 - 2024/11/1
N2 - Background: Surgical procedures in anticoagulated patients require specific attention due to increased bleeding risk. Preoperative anticoagulation interruption in high-risk patients is often necessary. Bridging anticoagulation with low-molecular-weight heparin (LMWH) minimizes thromboembolic risk, but its effect on international normalized ratio (INR) measurement is not well established, necessitating careful monitoring and individual assessment. Objectives: To investigate the effect of heparin bridging on INR measurements in anticoagulated patients on vitamin K antagonist (VKA) and in in vitro spiking experiments. Methods: Thirty-eight anticoagulated patients on VKA undergoing valve replacement surgery were studied using 2 plasma-based INR assays and 1 whole blood point-of-care INR method at multiple time points after postoperatively resuming VKA. In addition, INR levels in pooled plasma of both normal and VKA-treated individuals were compared, with 7 spiked concentrations of LMWH or unfractionated heparin (UFH) in 4 INR assays. Results: In LMWH-bridged anticoagulated patients, the INR results obtained with HemosIL RecombiPlasTin and point-of-care Coaguchek were significantly higher than those obtained with STA Hepato Prest within 3 days after restart of VKA. After spiking LMWH or UFH in various concentrations into pooled plasma, only the STA Hepato Prest assay showed no interference in INR measurement within the therapeutic range (1.0-2.0 international units/mL) in both VKA and normal plasma. All other assays showed substantial interference, with the Thromborel S assay being the most heparin-sensitive assay. Conclusion: Differences between INR methods are seen within 72 hours after restarting VKA in postoperative patients who receive LMWH bridging. In vitro experiments using LMWH and UFH show the interference of heparin in multiple INR methods, even with concentrations below the suppliers’ stated heparin interference limits.
AB - Background: Surgical procedures in anticoagulated patients require specific attention due to increased bleeding risk. Preoperative anticoagulation interruption in high-risk patients is often necessary. Bridging anticoagulation with low-molecular-weight heparin (LMWH) minimizes thromboembolic risk, but its effect on international normalized ratio (INR) measurement is not well established, necessitating careful monitoring and individual assessment. Objectives: To investigate the effect of heparin bridging on INR measurements in anticoagulated patients on vitamin K antagonist (VKA) and in in vitro spiking experiments. Methods: Thirty-eight anticoagulated patients on VKA undergoing valve replacement surgery were studied using 2 plasma-based INR assays and 1 whole blood point-of-care INR method at multiple time points after postoperatively resuming VKA. In addition, INR levels in pooled plasma of both normal and VKA-treated individuals were compared, with 7 spiked concentrations of LMWH or unfractionated heparin (UFH) in 4 INR assays. Results: In LMWH-bridged anticoagulated patients, the INR results obtained with HemosIL RecombiPlasTin and point-of-care Coaguchek were significantly higher than those obtained with STA Hepato Prest within 3 days after restart of VKA. After spiking LMWH or UFH in various concentrations into pooled plasma, only the STA Hepato Prest assay showed no interference in INR measurement within the therapeutic range (1.0-2.0 international units/mL) in both VKA and normal plasma. All other assays showed substantial interference, with the Thromborel S assay being the most heparin-sensitive assay. Conclusion: Differences between INR methods are seen within 72 hours after restarting VKA in postoperative patients who receive LMWH bridging. In vitro experiments using LMWH and UFH show the interference of heparin in multiple INR methods, even with concentrations below the suppliers’ stated heparin interference limits.
KW - anticoagulation
KW - heparin
KW - international normalized ratio
KW - low-molecular-weight heparin
KW - vitamin K
U2 - 10.1016/j.rpth.2024.102616
DO - 10.1016/j.rpth.2024.102616
M3 - Article
SN - 2475-0379
VL - 8
JO - Research and practice in thrombosis and haemostasis
JF - Research and practice in thrombosis and haemostasis
IS - 8
M1 - 102616
ER -