Comparison of four point of care devices for activated clotting time (ACT) on adult patients undergoing cardiopulmonary bypass

2019 ◽  
Vol 493 ◽  
pp. S670-S671
Author(s):  
H. Li ◽  
C. Serrick ◽  
P. Yip
Keyword(s):  
Cardiopulmonary Bypass ◽  
Point Of Care ◽  
Adult Patients ◽  
Clotting Time ◽  
Activated Clotting Time

A comparative analysis of four activated clotting time measurement devices in cardiac surgery with cardiopulmonary bypass

Perfusion ◽  
2020 ◽  
pp. 026765912094935
Author(s):  
Han Li ◽  
Cyril Serrick ◽  
Vivek Rao ◽  
Paul M Yip
Keyword(s):  
Cardiac Surgery ◽  
Cardiopulmonary Bypass ◽  
System Analysis ◽  
Point Of Care ◽  
Measurement Range ◽  
Medical Decision ◽  
Clotting Time ◽  
Activated Clotting Time ◽  
Decision Points ◽  
Heparin Anticoagulation

Background: In cardiac surgery on cardiopulmonary bypass (CPB), heparin anticoagulation is monitored by point-of-care measurement of activated clotting time (ACT). The objective of this study was to compare four ACT systems in cardiac surgery in terms of their reproducibility, agreement and potential clinical impact at relevant medical decision points. Methods: The study included 40 cardiac surgery patients. Samples were taken at five time points before (T1), after heparinization for CPB (T2, T3, T4), and after heparin reversal (T5). The reproducibility, correlation, and differences in ACT values were assessed with two devices from each of the four ACT systems: Instrumentation Laboratory Hemochron Elite (Hmch), Medtronic HMS Plus (HMS), Abbott i-STAT, and Helena Abrazo. Subrange analyses were performed for low ACT values (results from T1, T5) and high ACT values (results from T2, T3, T4). Results: Within-system analysis showed strong linear correlation between paired measurements (R = 0.968-0.993). However, Hmch showed poorer reproducibility with highest proportion of values that exceed a difference of 10% and highest overall standard error of 74 seconds across the measurement range compared to that of the others (range 39-47 seconds, respectively). For inter-system comparison, using Hmch as reference, ACTs were strongly correlated as follows: HMS (R = 0.938), i-STAT (R = 0.911), and Abrazo (R = 0.911). Agreement analysis in the high ACT range showed HMS tended to have higher ACT values with +11% bias over Hmch, whereas i-STAT (–8% bias) and Abrazo (–13% bias) tended to underestimate. Post-protamine ACT results were dependent on device type where Hmch yielded highest post-protamine ACT (+13% higher than baseline) compared to –16% for HMS, –10% for iSTAT and 0% for Abrazo. Conclusions: Each device had individual reproducibility and biases, which may impact peri-operative heparin management. Careful validation must be undertaken when adopting a different method as decision limits would be affected. Clinicians should also be cautious using ACT as the only indicator for full heparin reversal.

Evaluation of a New Point-of-care Celite-activated Clotting Time Analyzer in Different Clinical Settings

2003 ◽  
Vol 99 (1) ◽  
pp. 54-59 ◽  
Author(s):  
Rita Paniccia ◽  
Sandra Fedi ◽  
Fiorella Carbonetto ◽  
Daniela Noferi ◽  
Paolo Conti ◽  
...  
Keyword(s):  
Cardiopulmonary Bypass ◽  
Point Of Care ◽  
Factor Xa ◽  
Interventional Cardiology ◽  
Heparin Therapy ◽  
Clinical Settings ◽  
Clotting Time ◽  
New Device ◽  
Activated Clotting Time ◽  
Heparin Plasma

Background Activated clotting time (ACT) is used to monitor heparin therapy during cardiopulmonary bypass, interventional cardiology, and hemodialysis. Traditionally, ACT is performed by use of the Hemochron system. Recently, a new device, the i-STAT system, has been introduced to measure ACT. The aim of this study was to correlate the performances of these two systems and to compare ACT values with heparin levels. Methods One hundred sixty-five samples from 29 patients undergoing cardiopulmonary bypass or hemodialysis were assayed in duplicate with two Hemochron and two i-STAT devices. Heparin levels were determined by anti-factor Xa assay. Results The Hemochron ACT ranged from 88 to 1,028 s, and the i-STAT ACT ranged from 80 to 786 s. Heparin plasma levels ranged from 0.01 to 10.8 U/mL. Bland-Altman analysis showed a mean difference between the two methods of 24 +/- 101 s. Strong relationships between anti-factor Xa activity and Hemochron ACTs (r2 = 0.69, P < 0.001) and i-STAT ACTs (r2 = 0.79, P < 0.001) were observed. During cardiac surgery, significant correlations were found: Hemochron, r2 = 0.61, P < 0.001 and i-STAT, r2 = 0.74, P < 0.001. During hemodialysis, relationships between anti-factor Xa activity and ACTs were found: Hemochron, r2 = 0.62, P < 0.001 and i-STAT, r2 = 0.55, P < 0.001. Conclusions During cardiopulmonary bypass procedure and hemodialysis, i-STAT provides measurements of clotting time quite similar to Hemochron ACT, which were significantly correlated with heparin levels.

scholarly journals Point-of-Care Measurement of Activated Clotting Time for Cardiac Surgery as measured by the Hemochron Signature Eliteand the Abbott i-STAT: Agreement, Concordance, and Clinical Reliability

2019 ◽  
Author(s):  
Daniel Dirkmann ◽  
Elisabeth Nagy ◽  
Martin Walter Britten ◽  
Juergen Peters
Keyword(s):  
Cardiac Surgery ◽  
Cardiopulmonary Bypass ◽  
Linear Correlation ◽  
Point Of Care ◽  
Clotting Time ◽  
Cohen’S Kappa ◽  
Cohen's Kappa ◽  
Activated Clotting Time ◽  
Heparin Anticoagulation ◽  
Parallel Measurements

Abstract Background: Since inadequate heparin anticoagulation and insufficient reversal can result in complications during cardiopulmonary bypass (CPB) surgery, heparin anticoagulation monitoring by point-of-care (POC) activated clotting time (ACT) measurements is essential for CPB initiation, maintainance, and anticoagulant reversal. However, concerns exist regarding reproducibility of ACT assays and comparability of devices. Methods: We evaluated the agreement of ACT assays using four parallel measurements performed on two commonly used devices each (i.e., two Hemochron Signature Elite (Hemochron) and two Abbott i-STAT (i-STAT) devices, respectively). Blood samples from 30 patients undergoing cardiac surgery on CPB were assayed at specified steps (baseline, after heparin administration, after protamine administration) with four parallel measurements (two of each device type) using commercial Kaolin activated assays provided by the respective manufactures. Measurements were compared between identical and different device types using linear regression, Bland-Altman analyses, and calculation of Cohen’s kappa coefficient. Results: Parallel i-STAT ACTs demonstrated a good linear correlation (r=0.985). Bias, as determined by Bland-Altman analysis, was low (-3.8s; 95% limits of agreement (LOA): -77.8 -70.2s), and Cohen’s Kappa demonstrated good agreement (kappa=0.809). Hemochron derived ACTs demonstrated worse linear correlation (r=0.782), larger bias with considerably broader LOA (-13.14s; 95%LOA:-316.3-290s), and lesser concordance between parallel assays (kappa=0.554). Although demonstrating a fair linear correlation (r=0.815), parallel measurements on different ACT-devices showed large bias (-20s; 95% LOA: -290-250s) and little concordance (kappa=0.368). Overall, disconcordant results according to clinically predefined target values were more frequent with the Hemochron than i-STAT. Furthermore, while discrepancies in ACT between two parallel iSTAT assays showed little or no clinical relevance, deviations from parallel Hemochron assays and iSTAT versus Hemochron measurements revealed marked and sometimes clinically critical deviations. Conclusion: Currently used ACT point-of-care devices cannot be used interchangeably. Furthermore, our data question the reliability of the Hemochron in assessing adequacy of heparin anticoagulation monitoring for CPB. Keywords: Activated clotting time, ACT, method comparison, anticoagulation, cardiopulmonary bypass, heparin, protamine

The activated clotting time loading dose response ratio (ACTLORR) as an indicator of heparin demand during cardiopulmonary bypass

Perfusion ◽  
1996 ◽  
Vol 11 (2) ◽  
pp. 125-130 ◽  
Author(s):  
Ian J Reece ◽  
Gerrard Linley ◽  
Habib Al Tareif ◽  
Rollie DeVroege ◽  
Jitesh Tolia ◽  
...  
Keyword(s):  
Cardiopulmonary Bypass ◽  
Dose Response ◽  
Loading Dose ◽  
Response Ratio ◽  
Clotting Time ◽  
Activated Clotting Time

scholarly journals Point-of-Care Measurement of Activated Clotting Time for Cardiac Surgery as measured by the Hemochron Signature Eliteand the Abbott i-STAT: Agreement, Concordance, and Clinical Reliability

2019 ◽  
Author(s):  
Daniel Dirkmann ◽  
Elisabeth Nagy ◽  
Martin Walter Britten ◽  
Juergen Peters
Keyword(s):  
Cardiac Surgery ◽  
Linear Correlation ◽  
Point Of Care ◽  
Clotting Time ◽  
Cohen’S Kappa ◽  
Cohen's Kappa ◽  
Activated Clotting Time ◽  
Target Values ◽  
Heparin Anticoagulation ◽  
Parallel Measurements

Abstract Background: Since inadequate heparin anticoagulation and insufficient reversal can result in complications during cardiopulmonary bypass (CPB) surgery, heparin anticoagulation monitoring by point-of-care (POC) activated clotting time (ACT) measurements is essential for CPB initiation, maintainance, and anticoagulant reversal. However, concerns exist regarding reproducibility of ACT assays and comparability of devices. Methods: We evaluated the agreement of ACT assays using four parallel measurements performed on two commonly used devices each (i.e., two Hemochron Signature Elite (Hemochron) and two Abbott i-STAT (i-STAT) devices, respectively). Blood samples from 30 patients undergoing cardiac surgery on CPB were assayed at specified steps (baseline, after heparin administration, after protamine administration) with four parallel measurements (two of each device type) using commercial Kaolin activated assays provided by the respective manufactures. Measurements were compared between identical and different device types using linear regression, Bland-Altman analyses, and calculation of Cohen’s kappa coefficient. Results: Parallel i-STAT ACTs demonstrated a good linear correlation (r=0.985). Bias, as determined by Bland-Altman analysis, was low (-3.8s; 95% limits of agreement (LOA): -77.8 -70.2s), and Cohen’s Kappa demonstrated good agreement (kappa=0.809). Hemochron derived ACTs demonstrated worse linear correlation (r=0.782), larger bias with considerably broader LOA (-13.14s; 95%LOA:-316.3-290s), and lesser concordance between parallel assays (kappa=0.554). Although demonstrating a fair linear correlation (r=0.815), parallel measurements on different ACT-devices showed large bias (-20s; 95% LOA: -290-250s) and little concordance (kappa=0.368). Overall, disconcordant results according to clinically predefined target values were more frequent with the Hemochron than i-STAT. Furthermore, while discrepancies in ACT between two parallel iSTAT assays showed little or no clinical relevance, deviations from parallel Hemochron assays and iSTAT versus Hemochron measurements revealed marked and sometimes clinically critical deviations. Conclusion: Currently used ACT point-of-care devices cannot be used interchangeably. Furthermore, our data question the reliability of the Hemochron in assessing adequacy of heparin anticoagulation monitoring for CPB.

A Multicenter Comparison of 2 Point-of-Care Activated Clotting Time Test Systems

2019 ◽  
Vol 4 (3) ◽  
pp. 468-470
Author(s):  
Evelien W.M. Kemna ◽  
Mark W.M. Schellings ◽  
Georgios J. Vlachojannis ◽  
Florian Falter ◽  
Antoinette Milané-Santman ◽  
...  
Keyword(s):  
Point Of Care ◽  
Clotting Time ◽  
Test Systems ◽  
Activated Clotting Time ◽  
Time Test

Factors associated with errors in the heparin dose response test: recommendations to improve individualized heparin management in cardiopulmonary bypass

Perfusion ◽  
2020 ◽  
pp. 026765912095297
Author(s):  
Min-Ho Lee ◽  
William Riley
Keyword(s):  
Cardiopulmonary Bypass ◽  
Dose Response ◽  
Clotting Time ◽  
Critical Aspect ◽  
Heparin Dose ◽  
Factors Associated ◽  
Heparin Concentration ◽  
Activated Clotting Time

Background: A critical aspect of cardiopulmonary bypass (CPB) is to achieve full anticoagulation to prevent thrombosis and consumptive coagulation without using excessive amount of heparin. This can be achieved with heparin dose response (HDR) test in vitro to calculate an individualized heparin bolus to reach a target activated clotting time (ACT) and heparin concentration. However, we often observe that the measured ACT (mACT) with the calculated heparin bolus gives significant errors, both positive (mACT is higher than expected) and negative (mACT is lower), from expected ACT (eACT). Methods: We performed a retrospective study of 250 patients who underwent cardiac surgery to attain an error distribution of the mACT from eACT with calculated heparin bolus. In addition, it is aimed to identify possible patterns of baseline ACT (bACT), calculated heparin concentration (CHC) and HDR slope that are associated with the significant positive and negative errors. Results: We found that individualized heparin bolus by HDR test is consistently underestimated while it gave a significant number of positive and negative errors. Further analysis indicates that significant negative errors correlate with high bACT and slope and low CHC while significant positive errors with low bACT and slope and high CHC. Conclusion: The mACT can be substantially different from eACT. The accuracy of the HDR test appears to be dependent upon bACT, slope, and CHC. Based on our analysis, we provide several recommendations and a flow chart to improve the quality of individualized heparin management on CPB.

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