Platelet function changes in different cardiac surgery subgroups as evaluated with an innovative technology (original) (raw)
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Platelet Function Changes as Monitored by Cone and Plate(let) Analyzer during Beating Heart Surgery
The Heart Surgery Forum, 2004
Background: Off-pump coronary artery bypass (OPCAB) is believed to reduce cardiopulmonary bypass (CPB)-related complications, including platelet damage. A hypercoagulable state instead of coagulopathy has been reported following OPCAB surgeries due to CPB. Whether platelet function is changed when the injurious effect of CPB is eliminated was investigated. Methods: Platelet function was determined with the cone and plate(let) analyzer (CPA) method. The 2 parameters, average size (AS) and surface coverage (SC) of platelet aggregates, were measured with the CPA method to assess platelet aggregation and adhesion. These parameters were evaluated, and their values were compared at several stages of OPCAB surgery. The correlations of postoperative bleeding with platelet function at different stages of the surgery and with other factors, such as platelet count, hematocrit, and transfusions, were studied. Results: Both AS and SC increased during several stages of the operation, and postoperative values (mean ± SD) were significantly higher than preoperative values (30.4 ± 8.1 µm 2 versus 23.3 ± 6.9 µm 2 for AS [P = .02] and 7.6% ± 3.6% versus 5.2% ± 1.8% for SC [P = .04]). The mean total bleeding volume was 875 ± 415 mL. Preoperative AS and SC were the only parameters significantly (P = .01) and linearly (r = 0.7) related to postoperative bleeding. Conclusions: An increased platelet function, as determined by the CPA method, is found following OPCAB surgery. This phenomenon is probably at least partially responsible for the thrombogenic state after OPCAB surgery. Lack of platelet injury attributed to CPB may divert the system toward a more thrombogenic state. Preoperative platelet function, as evaluated by the CPA method, is an independent risk factor determining postoperative bleeding.
Anaesthesia, 2011
Platelet dysfunction after cardiopulmonary bypass contributes to microvascular bleeding and is associated with blood transfusion and resternotomy. Platelet count can be readily performed, but currently there are no standardised, reproducible, rapidly available platelet function tests. We studied platelet function as measured by multiple electrode platelet aggregometery (multiplate) and light transmission aggregometry in 44 patients undergoing routine coronary artery surgery. Platelet aggregation as measured by multiplate was reduced during and after cardiopulmonary bypass compared with baseline with evidence of partial recovery by the time of transfer to ITU. In patients transfused blood, platelet aggregation measured by multiplate was reduced during chest closure with adenosine diphosphate (18 U vs 29 U, p = 0.01) and thrombin receptor agonist peptide-6 agonist (65 U vs 88 U, p = 0.01) compared with patients not transfused. This suggests that multiplate, a new point of care analyser, can detect platelet dysfunction in this setting.
Journal of Interventional Cardiology, 2015
Objective: We sought to examine the relationship between preoperative platelet function and perioperative bleeding in patients undergoing CABG. Background: There are many ways to measure platelet aggregability. Little is known about their correlations with one another, or with bleeding. Methods: We prospectively studied 50 patients undergoing a first isolated off-pump CABG. Thirty-four were exposed to a thienopyridine prior to surgery; 16 were not. Preoperative platelet function was measured by VerifyNow 1 , TEG 1 , AggreGuide TM , Plateletworks 1 , vasodilator-stimulated phosphoprotein (VASP) phosphorylation, and light transmission aggregometry. Bleeding was assessed 2 ways: drop from pre-to nadir postoperative hematocrit, and chest tube drainage. Correlation coefficients were calculated using Spearman's rank-order correlation. Results: Mean age was 62 years. Patient characteristics and surgical details were similar between the thienopyridine-exposed and non-exposed patients. The correlation coefficients between the 4 point-of-care platelet function measurements and hematocrit change ranged from À0.2274 to 0.2882. Only Plateletworks 1 correlated with drop in hematocrit (r ¼ 0.2882, P ¼ 0.0470). The correlation coefficients between each of the 4 point-of-care platelet function tests and the chest tube drainage were also poor, ranging from À0.3073 to 0.2272. Both AggreGuide TM (r ¼ À0.3073, P ¼ 0.0317) and VASP (r ¼ À0.3187, P ¼ 0.0272) were weakly but significantly correlated with chest tube drainage. The correlation among the 4 point-of-care platelet function measurements was poor, with coefficients ranging from À0.2504 to 0.1968. Conclusions: We observed little correlation among 4 platelet function tests, and between those assays and perioperative bleeding defined 2 different ways. Whether any of these assays should be used to guide decision making in individual patients is unclear.
Anaesthesia, 2015
This systematic review and meta-analysis appraises the utility of point-of-care platelet function tests for predicting blood loss and transfusion requirements in cardiac surgical patients, and analyses whether their use within a transfusion management algorithm is associated with improved patient outcomes. We included 30 observational studies incorporating 3044 patients in the qualitative assessment, and nine randomised controlled trials including 1057 patients in the meta-analysis. Platelet function tests demonstrated significant variability in their ability to predict blood loss and transfusion requirements. Their use within a blood transfusion algorithm demonstrated a reduction in blood loss at longest follow-up (mean difference À102.9 ml (95% CI À149.9 to À56.1 ml), p < 0.001), and transfusion of packed red cells (RR 0.86 (95% CI 0.78À0.94), p = 0.001) and fresh frozen plasma (RR 0.42 (95% CI 0.30À0.59), p < 0.001). Viscoelastic methods used in combination with other platelet function tests achieved greater reduction in blood loss (mean difference À111.8 ml (95% CI À174.9 to À49.1 ml), p = 0.0005) compared with their use alone (mean difference À90.6 ml (95% CI 166.1À15.0 ml), p = 0.02). We conclude that incorporation of pointof-care platelet function tests into transfusion management algorithms is associated with a reduction in blood loss and transfusion requirements in cardiac surgery patients.
Journal of Cardiothoracic Surgery
Background: As the incidence of cardiovascular diseases increases, the use of antiplatelet therapy is widely recognized. This presents clinicians with the challenge of balancing the risk of thrombotic and bleeding complications. Platelet dysfunction is one of the causes of postoperative bleedings and their etiology is not fully understood. Platelets receptors point-of-care investigation is of a remarkable value in assessing patients risk of bleeding. Reliable assessment of platelet function can improve treatment. The aim of this study was to evaluate the activity of platelet receptors in patients qualified for cardiac surgery, taking into account organ dysfunctions and pharmacological therapy applied in these patients. Methods: Seventy-one cardiac surgical patients were analyzed before surgery using multiple electrode aggregometry with the use of the ADP test and ASPI test. The cutoff values were determined based on the manufacturer's recommendations. Patients were divided into four groups: Group I (33/71 patients, without platelet dysfunctions), Group II (6/71 patients, ADP < 710 AU x min), Group III (13/71 patients, ASPI < 570 AU x min) and Group IV (19 / 71 patients, ADP < 710 AU x min and ASPI < 570 AU x min). Biochemical data defining the efficiency of the liver and kidneys, the list of preoperative drugs used and the requirement for transfusion throughout the study group were collected. Results: The study group included 41 males (57.7%) and 30 females (42.3%), mean age 66 years. The majority of patients (94.4%) had platelet counts within the normal range, but platelet function was impaired in more than half of the studied patients (53.5%). No relationship was found between the biochemical markers of the kidneys and liver and the function of the ADP and ASPI receptors, while receptors activities were related (rs = 0.72, p < 0.001), and both associated with platelet count (rs = 0.55, p < 0.001 and rs = 0.42, p < 0.001, respectively). Platelet receptors activity was not related to the postoperative need for any type of transfusion as well as the applied preoperative pharmacological therapy. Conclusions: Early identification of patients at high risk of bleeding, using point-of-care platelet function assessment tests, enables a targeted therapeutic pathway. Due to the variety of factors affecting the activity of platelets, finding a specific cause of this pathology is extremely difficult. According to our study, the correlation between platelet receptor disorders and mild to moderate liver and kidney injury has not been demonstrated. However, platelet receptors dysfunction has been shown to be associated with a decreased number of platelets.
Platelet Function Test in Coronary Artery Bypass Grafting: Does It Predict Postoperative Bleeding?
Journal of Cardiac Critical Care TSS, 2021
Background Patients undergoing on-pump coronary artery bypass grafting (CABG) are at increased risk of perioperative bleeding and morbidity associated with transfusion as a result of acquired and pharmacologically induced impaired platelet function. Settings and Design In this a prospective observational study where 52 patients underwent on-pump CABG were analyzed with ROTEM platelet aggregometry. Materials and Methods Patients were assigned to the “nonexcessive” and “excessive” postoperative bleeding groups according to the postoperative chest tube drainage over 24 hours. Platelet function was assessed by ROTEM platelet using three different activators (arachidonic acid, adenosine diphosphate, and thrombin receptor-activating peptide), at two perioperative time points (T1, before heparinization and T2, 5–10 minutes after protamine administration). Results There were no differences regarding demographic, pre–cardiopulmonary bypass (CPB) platelet count and antiplatelet therapy. Plate...
Journal of Cardiac Critical Care TSS, 2021
Patients undergoing cardiac surgery are at risk of excessive bleeding and its associated complications. Excessive bleeding during and after cardiac surgery has an incidence of ~20%. Massive bleeding and subsequent requirement for blood product administration and mediastinal reexploration are associated with significant morbidity and mortality. Postoperative, nonsurgical bleeding in cardiac surgical patients is often multifactorial. Platelet dysfunction, excessive fibrinolysis, hypothermia, preoperative anemia, and deficiency of coagulation factors or their dilution are all suggested etiologies of postoperative bleeding. In the Arachidonic Acid Thromboelastometry (ARATEM) test, platelets are activated with arachidonic acid; in Adenosine diphosphate Thromboelastometry (ADPTEM) test, platelets are activated with adenosine diphosphate; and in TRAPTEM test, platelets are activated with thrombin receptor-activating peptide 6. Measurement time is 6 minutes, and results are expressed in thr...
Early platelet recovery following cardiac surgery with cardiopulmonary bypass
Platelets, 2016
Coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) is frequently associated with low platelet count (PC) and disturbed platelet function (PF). While PC is easy to measure, PF is more difficult to assess. Moreover, the time-related platelet dysfunction and recovery after CPB is not fully elucidated. Platelet dysfunction could lead to bleeding but also to coronary graft failure. Laboratory tests could provide more insights into PF after CABG. The aim of the current study was to investigate the time-related PF induced by CPB. Blood samples of 20 patients with a preoperative PC of more than 250 × 10(9)/L were collected before incision, after weaning from CPB, and 24 h postoperative. Platelet contribution to coagulation was quantified by PLTEM (calculated by means of EXTEM and FIBTEM results). PF was assessed by multiple electrode impedance aggregometry (MEIA) in whole blood and by light transmission aggregometry (LTA) in platelet-rich plasma after stimulation with arachidonic acid (AA), adenosine diphosphate, collagen, and thrombin-receptor-activating peptide. LTA and MEIA analysis demonstrated significant platelet dysfunction after CPB, with partial recovery within 24 h after surgery. AA-induced platelet aggregation increased to higher levels within 24 h after surgery compared to baseline values as measured by LTA. PLTEM maximum clot firmness remained unchanged throughout the study. Correlation analyses revealed that MEIA and rotational thromboelastometry (ROTEM), but not LTA, were dependent on PC and hematocrit. No correlations were found between LTA, MEIA, ROTEM, PC, and clinical outcome parameters. Our results demonstrate a reversible platelet dysfunction recovering within 24 h after CPB. Interestingly, AA-induced platelet aggregation increases to higher levels during the first 24 h postoperatively, which might be important for early initiation of antiplatelet therapy after CABG. MEIA as POC test is able to detect platelet dysfunction during cardiac surgery with a PC of ≥150 × 10(9)/L.
Heart, Lung and Circulation, 2012
Increasing numbers of patients are undergoing cardiac surgery on dual antiplatelet therapy following previous percutaneous coronary intervention. The dilemma of stopping antiplatelet therapy prior to surgery with risk of stent thrombosis, versus continuation and risk of post-operative bleeding has received much debate. Currently, an accurate and standardised method of predicting antiplatelet drug efficacy has not yet been determined and significant inter-individual variance has been shown. This review focuses on the most widely used laboratory and point of care assays currently available to measure platelet function and recent published data evaluating these methods. Further studies may enable predictive values to be defined, to guide the practicing clinician in balancing the risk of thrombosis versus haemorrhage.