Point-of-care (POC) measurement of coagulation after cardiac surgery

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.

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Use of point-of-care test in identification of patients who can benefit from desmopressin during cardiac surgery: a randomised controlled trial

The Lancet ◽

10.1016/s0140-6736(98)12494-7 ◽

1999 ◽

Vol 354 (9173) ◽

pp. 106-110 ◽

Cited By ~ 99

Author(s):

George J Despotis ◽

Vladimir Levine ◽

Rao Saleem ◽

Edward Spitznagel ◽

J Heinrich Joist

Keyword(s):

Cardiac Surgery ◽

Randomised Controlled Trial ◽

Point Of Care ◽

Controlled Trial ◽

Point Of Care Test ◽

Randomised Controlled

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Coagulopathy in Cardiac Surgery: Etiology and Treatment Options

Cardiothoracic Critical Care ◽

10.1093/med/9780190082482.003.0033 ◽

2020 ◽

pp. 313-322

Author(s):

Dana Teodorescu ◽

Caroline Larkin

Keyword(s):

Cardiac Surgery ◽

Laboratory Testing ◽

Blood Count ◽

Complete Blood Count ◽

Point Of Care ◽

Treatment Options ◽

Coagulation Factors ◽

Bleeding Diathesis ◽

Standard Laboratory ◽

Post Cardiac Surgery

This chapter reviews the causes and outlines an approach to the management of coagulopathy following cardiac surgery. Bleeding after cardiac surgery is common and expected up to a rate of 2 mL/kg/h for the first 6 hours. A more significant hemorrhage needs to be investigated and treated. Causes are often multifactorial. It is imperative that surgical causes be excluded early concomitant to providing resuscitation, investigating other medical causes for bleeding, and treating coagulopathy empirically until laboratory testing becomes available. The most frequent causes for coagulopathy post–cardiac surgery are excess heparinization, prolonged cardiopulmonary bypass time, hypothermia, acidosis, and preexisting bleeding diathesis. The management of coagulopathy implies maintenance of the normal physiological conditions for coagulation, reversal of excess heparinization, treatment of hyperfibrinolysis, maintaining normal levels of coagulation factors, and transfusion of platelets if thrombocytopenia or platelet dysfunction occurs. The chapter reviews what is involved in standard laboratory testing (complete blood count, prothrombin time, activated partial thromboplastin time, fibrinogen level, etc.) for coagulopathy. Also discussed is point-of-care testing and how the results from these tests should be interpreted. The chapter details the various blood products that are required in this scenario and suggests doses and transfusion thresholds.

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Minimal invasive extracorporeal circulation preserves platelet function after cardiac surgery: a prospective observational study

Perfusion ◽

10.1177/0267659119866289 ◽

2019 ◽

Vol 35 (2) ◽

pp. 138-144

Author(s):

Helena Argiriadou ◽

Polychronis Antonitsis ◽

Anna Gkiouliava ◽

Evangelia Papapostolou ◽

Apostolos Deliopoulos ◽

...

Keyword(s):

Cardiac Surgery ◽

Cardiopulmonary Bypass ◽

Correlation Coefficient ◽

Platelet Function ◽

Extracorporeal Circulation ◽

Point Of Care ◽

Postoperative Bleeding ◽

Minimal Invasive ◽

Elective Cardiac Surgery ◽

Impedance Aggregometry

Introduction: Cardiac surgery on conventional cardiopulmonary bypass induces a combination of thrombocytopenia and platelet dysfunction which is strongly related to postoperative bleeding. Minimal invasive extracorporeal circulation has been shown to preserve coagulation integrity, though effect on platelet function remains unclear. We aimed to prospectively investigate perioperative platelet function in a series of patients undergoing cardiac surgery on minimal invasive extracorporeal circulation using point-of-care testing. Methods: A total of 57 patients undergoing elective cardiac surgery on minimal invasive extracorporeal circulation were prospectively recruited. Anticoagulation strategy was based on individualized heparin management and heparin level–guided protamine titration performed in all patients with a specialized point-of-care device (Hemostasis Management System – HMS Plus; Medtronic, Minneapolis, MN, USA). Platelet function was evaluated with impedance aggregometry using the ROTEM platelet (TEM International GmbH, Munich, Germany). ADPtest and TRAPtest values were assessed before surgery and after cardiopulmonary bypass. Results: ADPtest value was preserved during surgery on minimal invasive extracorporeal circulation (58.2 ± 20 U vs. 53.6 ± 21 U; p = 0.1), while TRAPtest was found significantly increased (90 ± 27 U vs. 103 ± 38 U; p = 0.03). Postoperative ADPtest and TRAPtest values were inversely related to postoperative bleeding (correlation coefficient: −0.29; p = 0.03 for ADPtest and correlation coefficient: −0.28; p = 0.04 for TRAPtest). The preoperative use of P2Y12 inhibitors was identified as the only independent predictor of a low postoperative ADPtest value (OR = 15.3; p = 0.02). Conclusion: Cardiac surgery on minimal invasive extracorporeal circulation is a platelet preservation strategy, which contributes to the beneficial effect of minimal invasive extracorporeal circulation in coagulation integrity.

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