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Thrombelastographic characterization of the thrombin-like activity of Crotalus simus and Bothrops asper venoms. Blood Coagul Fibrinolysis 2017; 28:211-217. [DOI: 10.1097/mbc.0000000000000577] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Nielsen VG, Matika RW. Effects of iron and carbon monoxide on Lachesis muta muta venom-mediated degradation of plasmatic coagulation. Hum Exp Toxicol 2016; 36:727-733. [PMID: 27488540 DOI: 10.1177/0960327116661401] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Hypofibrinogenemia is an important clinical consequence following envenomation by Lachesis muta muta, usually attenuated or prevented by administration of antivenom. The venom of L. m. muta contains both a metalloproteinase fibrinogenase and a serine protease thrombin-like enzyme, and exposure of fibrinogen to iron (Fe) and carbon monoxide (CO) has been demonstrated to decrease its catalysis by such enzymes. Using thrombelastographic analytical techniques, it was determined that this venom displayed weak procoagulant effects combined with fibrinogenolytic effects, and pretreatment of plasma with Fe and CO markedly attenuated venom-mediated effects. Additional experiments involving heparin exposure and varying calcium concentrations demonstrated that modification of fibrinogen with Fe and CO in human plasma rendered fibrinogen not recognizable to the fibrinogenolytic metalloproteinase but did not prevent polymerization by the thrombin-like serine protease. Lastly, when venom was exposed to CO in isolation and then placed in plasma, the fibrinogenase was inhibited but the thrombin-like enzyme was not inhibited. In sum, utilizing relatively facile modifications, we demonstrated with thrombelastography that Fe and/or CO addition can protect human plasmatic coagulation from fibrinogenase activity but not the effects of the thrombin-like activity of L. m. muta venom.
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Affiliation(s)
- V G Nielsen
- Department of Anesthesiology, University of Arizona College of Medicine, Tucson, AZ, USA
| | - R W Matika
- Department of Anesthesiology, University of Arizona College of Medicine, Tucson, AZ, USA
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Mishra PK, Thekkudan J, Sahajanandan R, Gravenor M, Lakshmanan S, Fayaz KM, Luckraz H. The role of point-of-care assessment of platelet function in predicting postoperative bleeding and transfusion requirements after coronary artery bypass grafting. Ann Card Anaesth 2015; 18:45-51. [PMID: 25566711 PMCID: PMC4900327 DOI: 10.4103/0971-9784.148321] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE OBJECTIVE platelet function assessment after cardiac surgery can predict postoperative blood loss, guide transfusion requirements and discriminate the need for surgical re-exploration. We conducted this study to assess the predictive value of point-of-care testing platelet function using the Multiplate® device. METHODS Patients undergoing isolated coronary artery bypass grafting were prospectively recruited ( n = 84). Group A ( n = 42) patients were on anti-platelet therapy until surgery; patients in Group B ( n = 42) stopped anti-platelet treatment at least 5 days preoperatively. Multiplate® and thromboelastography (TEG) tests were performed in the perioperative period. Primary end-point was excessive bleeding (>2.5 ml/kg/h) within first 3 h postoperative. Secondary end-points included transfusion requirements, re-exploration rates, intensive care unit and in-hospital stays. RESULTS Patients in Group A had excessive bleeding (59% vs. 33%, P = 0.02), higher re-exploration rates (14% vs. 0%, P < 0.01) and higher rate of blood (41% vs. 14%, P < 0.01) and platelet (14% vs. 2%, P = 0.05) transfusions. On multivariate analysis, preoperative platelet function testing was the most significant predictor of excessive bleeding (odds ratio [OR]: 2.3, P = 0.08), need for blood (OR: 5.5, P < 0.01) and platelet transfusion (OR: 15.1, P < 0.01). Postoperative "ASPI test" best predicted the need for transfusion (sensitivity - 0.86) and excessive blood loss (sensitivity - 0.81). TEG results did not correlate well with any of these outcome measures. CONCLUSIONS Peri-operative platelet functional assessment with Multiplate® was the strongest predictor for bleeding and transfusion requirements in patients on anti-platelet therapy until the time of surgery.
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Affiliation(s)
- Pankaj Kumar Mishra
- Department of Cardiothoracic Surgery, Heart and Lung Centre, Wolverhampton, United Kingdom WV10 0QP,
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Salama GS, Kaabneh MA, Almasaeed MN, Alquran MI. Intravenous lipids for preterm infants: a review. CLINICAL MEDICINE INSIGHTS-PEDIATRICS 2015; 9:25-36. [PMID: 25698888 PMCID: PMC4325703 DOI: 10.4137/cmped.s21161] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 12/17/2014] [Accepted: 12/30/2014] [Indexed: 01/21/2023]
Abstract
Extremely low birth weight infants (ELBW) are born at a time when the fetus is undergoing rapid intrauterine brain and body growth. Continuation of this growth in the first several weeks postnatally during the time these infants are on ventilator support and receiving critical care is often a challenge. These infants are usually highly stressed and at risk for catabolism. Parenteral nutrition is needed in these infants because most cannot meet the majority of their nutritional needs using the enteral route. Despite adoption of a more aggressive approach with amino acid infusions, there still appears to be a reluctance to use early intravenous lipids. This is based on several dogmas that suggest that lipid infusions may be associated with the development or exacerbation of lung disease, displace bilirubin from albumin, exacerbate sepsis, and cause CNS injury and thrombocytopena. Several recent reviews have focused on intravenous nutrition for premature neonate, but very little exists that provides a comprehensive review of intravenous lipid for very low birth and other critically ill neonates. Here, we would like to provide a brief basic overview, of lipid biochemistry and metabolism of lipids, especially as they pertain to the preterm infant, discuss the origin of some of the current clinical practices, and provide a review of the literature, that can be used as a basis for revising clinical care, and provide some clarity in this controversial area, where clinical care is often based more on tradition and dogma than science.
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Validation of rotational thromboelastometry during cardiopulmonary bypass: A prospective, observational in-vivo study. Eur J Anaesthesiol 2014; 31:68-75. [PMID: 23867776 DOI: 10.1097/eja.0b013e328363171a] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Rotational thromboelastometry (ROTEM) is a whole blood point-of-test used to assess the patient's coagulation status. Three of the available ROTEM tests are EXTEM, INTEM and HEPTEM. In the latter, heparinase added to the INTEM reagent inactivates heparin to reveal residual heparin effect. Performing ROTEM analysis during cardiopulmonary bypass (CPB) might allow the anaesthesiologist to anticipate the need for blood products. OBJECTIVE The goal of this study was to validate ROTEM analysis in the presence of very high heparin concentrations during CPB. DESIGN Prospective, observational trial. SETTING Single University Hospital. PARTICIPANTS Twenty patients undergoing coronary artery bypass grafting. MAIN OUTCOME MEASURE ROTEM analysis was performed before heparin administration (T0), 10 min after heparin (T1), at the end of CPB (T2) and 10 min after protamine (T3). The following tests were performed: EXTEM, INTEM, and HEPTEM. Heparin concentrations were measured at T1 and at the end of bypass (T2). RESULTS At T1, EXTEM differed from baseline for coagulation time: +26.7 s (18.4 to 34.9, P < 0.0001), α: -3° (1.0 to 5.4, P = 0.006) and A10: -4.4 mm (2.3 to 6.5, P = 0.0004). INTEM at T0 was different from HEPTEM at T1 for coagulation time: + 47 s (34.3 to 59.6, P > 0.0001), A10: -2.3 mm (0.5 to 4.0, P = 0.01) and α -2° (1.0 to 3.0; P = 0.0007). At T2, all parameters in EXTEM and HEPTEM related to fibrin-platelet interaction deteriorated significantly compared to T1. At T3, EXTEM and INTEM were comparable to EXTEM and HEPTEM at T2. CONCLUSION HEPTEM and EXTEM measurements are valid in the presence of very high heparin concentrations and can be performed before protamine administration in patients undergoing cardiac surgery with CPB. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01455454.
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Gertler R, Wiesner G, Tassani-Prell P, Braun SL, Martin K. Are the Point-of-Care Diagnostics MULTIPLATE and ROTEM Valid in the Setting of High Concentrations of Heparin and Its Reversal With Protamine? J Cardiothorac Vasc Anesth 2011; 25:981-6. [DOI: 10.1053/j.jvca.2010.11.020] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Indexed: 11/11/2022]
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Rahe-Meyer N, Solomon C, Tokuno ML, Winterhalter M, Shrestha M, Hahn A, Tanaka K. Comparative Assessment of Coagulation Changes Induced by Two Different Types of Heart-Lung Machine. Artif Organs 2010; 34:3-12. [DOI: 10.1111/j.1525-1594.2009.00792.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Rahe-Meyer N, Winterhalter M, Boden A, Froemke C, Piepenbrock S, Calatzis A, Solomon C. Platelet concentrates transfusion in cardiac surgery and platelet function assessment by multiple electrode aggregometry. Acta Anaesthesiol Scand 2009; 53:168-75. [PMID: 19175576 DOI: 10.1111/j.1399-6576.2008.01845.x] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND Platelet dysfunction contributes to the pathophysiology of bleeding complications during and after cardiac surgery. In most surgical institutions, no peri-operative point-of-care monitoring of platelet function is used. We evaluated the usefulness of the Multiplate platelet function analyser based on impedance aggregometry for identifying groups of patients at a high risk of transfusion of platelet concentrates (PC). METHODS Platelet function parameters were determined in 60 patients before and after routine cardiac surgery. Impedance aggregometry measurements were performed on Multiplate using ADP (ADPtest), collagen (COLtest) and thrombin receptor activating peptide (TRAPtest) as platelet activators. The correlations between the aggregometry results and the transfusion of PC were calculated. The results of the aggregation tests were also divided into tertiles and the differences in PC transfusion between the low and the high tertile were assessed. RESULTS Low aggregometry delimited groups of patients with significantly higher PC transfusion. In the receiver operating characteristic curve, low pre-operative aggregation in the ADPtest identified patients with high total transfusion of PC (area under the curve 0.74, P=0.001), while the ADPtest performed at the end of the operation identified patients with high PC transfusion on the intensive care unit (ICU) (area under the curve 0.76, P=0.002). CONCLUSIONS Near-patient platelet aggregation may allow the identification of patients with enhanced risk of PC transfusion, both pre-operatively and upon arrival on the ICU.
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Affiliation(s)
- N Rahe-Meyer
- Department of Anaesthesiology, Hannover Medical School, Hannover, Germany.
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Rahe-Meyer N, Winterhalter M, Hartmann J, Pattison A, Hecker H, Calatzis A, Solomon C. An Evaluation of Cyclooxygenase-1 Inhibition Before Coronary Artery Surgery: Aggregometry Versus Patient Self-Reporting. Anesth Analg 2008; 107:1791-7. [DOI: 10.1213/ane.0b013e3181865733] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Anticoagulant therapy during cardiopulmonary bypass. J Thromb Thrombolysis 2008; 26:218-28. [DOI: 10.1007/s11239-008-0280-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Accepted: 09/19/2008] [Indexed: 10/21/2022]
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Solomon C, Winterhalter M, Gilde I, Hoy L, Calatzis A, Rahe-Meyer N. Influence of the sample anticoagulant on the measurements of impedance aggregometry in cardiac surgery. MEDICAL DEVICES-EVIDENCE AND RESEARCH 2008; 1:23-30. [PMID: 22915904 PMCID: PMC3417906 DOI: 10.2147/mder.s3288] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Background: The standard method of assessment of platelet function is represented by light transmission aggregometry (LTA), performed in citrated platelet-rich plasma (PRP). With LTA, decrease and subsequent post-cardiopulmonary bypass (CPB) recovery of platelet function have been reported during cardiac surgery. Multiple electrode aggregometry (MEA) may be used as point-of-care method to monitor perioperative changes in platelet function. Since MEA assesses macroaggregation which is influenced by the plasmatic levels of unbound calcium, citrate may be inadequate as anticoagulant for MEA. We used citrate and heparin for MEA samples, to see with which anticoagulant the intraoperative decrease and postoperative recovery in platelet function previously described with other aggregometric methods in cardiac surgery may be observed with MEA. Methods: Blood was obtained from 60 patients undergoing routine cardiac surgery and the samples were collected in standard tubes containing unfractionated heparin (50 U/mL) or trisodium citrate (3.2%). The samples were obtained before CPB, at 30 minutes on CPB, end of CPB and on the first postoperative day. MEA was performed using the Multiplate® analyzer. Collagen (COLtest, 100 μg/mL) and TRAP-6 (thrombin receptor activating peptide, TRAPtest, 1mM/mL) were used as aggregation agonists. Results: Platelet aggregometric response decreased significantly during CPB. Platelet aggregation assessed using TRAP-6 as agonist on heparinized blood significantly correlated with the duration of CPB (r = −0.41, p = 0.001, 2-tailed Pearson test). The aggregometric analysis performed on the first postoperative day showed a significant recovery in platelet activity in the samples containing heparin (increase from 30 ± 22 U to 46 ± 27 U for the COLtest and from 70 ± 34 U to 95 ± 32 U for the TRAPtest, p < 0.001, Student’s t-test), while no significant recovery of platelet function could be established in the MEA measurements performed with citrated blood. Conclusions: The choice of blood sample anticoagulant used for impedance aggregometry influenced the platelet aggregation response. Postoperative platelet function recovery was only detected in the heparinized samples. Heparin seems to be better suited than citrate for the analysis of impedance aggregometry in heart surgery.
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Affiliation(s)
- Cristina Solomon
- Department of Anesthesiology, Hannover Medical School, Hannover, Germany
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Belcher PR, Ramnarine IR. Reply. J Cardiothorac Vasc Anesth 2007. [DOI: 10.1053/j.jvca.2006.12.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Muriithi EW, Belcher PR, Menys VC. Preoperative platelet inhibition and bleeding after cardiopulmonary bypass. J Thorac Cardiovasc Surg 2003; 125:739. [PMID: 12658225 DOI: 10.1067/mtc.2003.332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Ouriel K. The use of an aortoiliac side-arm conduit to maintain distal perfusion during thoracoabdominal aortic aneurysm repair. J Vasc Surg 2003; 37:214-8. [PMID: 12514606 DOI: 10.1067/mva.2003.72] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Thoracoabdominal aneurysm repair continues to be associated with a significant risk of operative complications, many of which are related to the prolonged period of aortic cross clamping inherent in the procedure. A variety of adjuvant techniques have been used in attempts to decrease morbidity, including atriofemoral extracorporal bypass, subarachnoid drainage, epidural cooling, and preliminary axillofemoral bypass. Herein is described a method to maintain distal perfusion with a side-arm conduit, originating from the most proximal aspect of the aortic graft and terminating on the left iliac artery. The technique has the potential to minimize hemodynamic instability while decreasing the period of pelvic and lower extremity ischemia and simplifying reattachment of aortic branch vessels. This method provides another option that can be considered in these technically demanding operative procedures.
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Affiliation(s)
- Kenneth Ouriel
- Department of Vascular Surgery, The Cleveland Clinic Foundation, Cleveland, OH 44195, USA.
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Belcher PR, Muriithi EW. Postoperative bleeding after coronary artery bypass surgery with cardiopulmonary bypass. Anesth Analg 2002; 95:1466; author reply 1467. [PMID: 12401657 DOI: 10.1097/00000539-200211000-00086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Muriithi EW, Belcher PR, Menys VC. Platelet dysfunction, platelet function tests and cardiopulmonary bypass with heparin anticoagulation. Thromb Res 2002; 107:81-2;author reply 83-4. [PMID: 12413594 DOI: 10.1016/s0049-3848(02)00209-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Muriithi EW, Belcher PR. Heparin and time-dependent platelet dysfunction during cardiac surgery. Blood Coagul Fibrinolysis 2002; 13:73-4. [PMID: 11994572 DOI: 10.1097/00001721-200201000-00012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Platelet aggregates and cardiopulmonary bypass: Reply. Ann Thorac Surg 2001. [DOI: 10.1016/s0003-4975(01)02416-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Muriithi EW, Belcher PR, Rao JN, Chaudhry MA, Nicol D, Wheatley DJ. The effects of heparin and extracorporeal circulation on platelet counts and platelet microaggregation during cardiopulmonary bypass. J Thorac Cardiovasc Surg 2000; 120:538-43. [PMID: 10962416 DOI: 10.1067/mtc.2000.108164] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
BACKGROUND Cardiopulmonary bypass is associated with platelet activation and reduced platelet counts. Platelet activation may artifactually lower platelet counts by causing aggregation. In vivo platelet activation may increase existent platelet microaggregation ex vivo. We studied platelet counts and existent platelet microaggregation at different stages of cardiopulmonary bypass. METHODS Twenty-one patients were studied before and after heparinization (300 U. kg(-1)) and at the end of cardiopulmonary bypass. Unaggregated (or single) platelets were counted in hirudin-anticoagulated blood, and total platelets were counted in ethylenediaminetetraacetic acid-anticoagulated blood. RESULTS The total platelet count, 198 +/- 61 x 10(9). L(-1), was unaffected by heparin and stayed at 197 +/- 60 x 10(9). L(-1) (P =.7) but fell during extracorporeal circulation; the hemodilution-corrected count was 163 +/- 52 x 10(9). L(-1) (P =.0004). Heparinization reduced the unaggregated platelet count from (mean +/- 1 SD) 178 +/- 62 x 10(9). L(-1) to 155 +/- 60 x 10(9). L(-1) (P =.0001). Extracorporeal circulation had little additional effect. The hemodilution-corrected count was 142 +/- 48 x 10(9). L(-1) (P =.6). CONCLUSIONS Heparinization caused platelet activation and increased existent platelet microaggregation ex vivo. During extracorporeal circulation, there was a reduction in total platelets that was greater than could be explained by hemodilution alone, but the unaggregated platelet count did not change significantly when corrected for hemodilution. Furthermore, the increased platelet microaggregation observed after heparinization was no longer evident after this loss. These findings suggest that during extracorporeal circulation, the platelets that formed into microaggregates after heparinization were lost from the circulation in preference to single platelets.
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Affiliation(s)
- E W Muriithi
- University of Glasgow Department of Cardiac Surgery, Royal Infirmary, Glasgow, Scotland.
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Muriithi EW, Belcher PR, Day SP, Menys VC, Wheatley DJ. Heparin-induced platelet dysfunction and cardiopulmonary bypass. Ann Thorac Surg 2000; 69:1827-32. [PMID: 10892931 DOI: 10.1016/s0003-4975(00)01299-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Cardiopulmonary bypass is associated with impaired platelet macroaggregation. Heparin contributes to platelet dysfunction before extracorporeal circulation. In vitro heparinization of whole blood does not impair macroaggregation. Heparin releases several endothelial proteins; thus heparin may inhibit macroaggregation indirectly. METHODS Patients undergoing operations using cardiopulmonary bypass and ABO blood group compatible volunteers were studied. Whole blood impedance aggregometry assessed macroaggregation in response to collagen (0.6 microg ml(-1)) in blood diluted either with normal saline or with platelet poor plasma, obtained from patients at different stages of cardiopulmonary bypass. RESULTS Before heparinization, blood diluted with its own platelet poor plasma recorded an impedance change of 13.0 (4.7 to 15.6) Ohms. Platelet poor plasma obtained after heparinization or during extracorporeal circulation reduced this response to 3.7 (1.1 to 8.4) and 2.0 (1.1 to 3.3) Ohms, respectively (both p < 0.0001 versus pre-heparin; n = 13). Macroaggregation in blood from volunteers was similarly inhibited by patients' platelet poor plasma (n = 30). The macroaggregatory response in blood sampled after heparinization for cardiopulmonary bypass, decreased gradually from 11.4 (8.2 to 15.9) Ohms immediately after sampling to 1.7 (1.4 to 4.1) Ohms 2 hours later (p < 0.0001; n = 11). CONCLUSIONS In vivo heparinization induces plasma changes that inhibit platelet macroaggregation. This is an indirect, delayed inhibition that is transferable in vitro to normal platelets.
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Affiliation(s)
- E W Muriithi
- Department of Cardiac Surgery, University of Glasgow, Royal Infirmary, Scotland.
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