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Abstract
The in vivo effects of Diaspirin Crosslinked Hemoglobin (DCLHb, Baxter Healthcare Corp.) on hematology and biochemistry are unknown. This study includes 6 calves (71.2±1.3 kg). In each animal a total of 2 litres of blood was exchanged for the same amount of hydroxylethyl starch (Haes, Fresenius) (n=3) or DCLHb (n=3), which is equivalent to 28cc/kg of blood substitute, over a period of 5 hours. The animals were allowed to survive 7 days. Blood samples were taken hourly during the perfusion protocol, at postoperative day (POD) 1, 2 and 7. ANOVA test was used for repeated measurements. Blood cell profiles were similar in both groups. Peak methemoglobinemia was 4.2% in the DCLHb group. Osmolarity was significantly higher in the DCLHb group with the greatest difference at POD 1 and 2. Postmortem analysis of the major organs did not show any sign of hemoglobin deposit in the DCLHb group. In the given setup DCLHb can be administered in a large quantity with good hematological tolerance and without any deposits in major organs. A prolonged plasma expander effect was observed. (Int J Artif Organs 2000; 23: 119–24)
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Zadeh BJ, Holazo R, Conlon C, Lazenby WD, Isom OW, Krieger KH. A clinical evaluation of three modern blood oxygenators. Perfusion 2016. [DOI: 10.1177/026765918700200404] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The purpose of this study was to assess the performance of three standard oxygenators in a clinical setting. The oxygenators selected included the Bard H1700, the Bentley CM-50 and the Cobe CML. Fifty CPB procedures were performed on patients undergoing elective CABG procedures in each group and prospectively analysed. Patient related parameters were collected in three subsets: preoperative, operative and postoperative, and organized into a data base on a standard 'Clinfo' system. The groups were then compared for statistically significant differences. The three groups were similar in all demographic and patient management categories examined. Overall morbidity and mortality were not significantly different. Parameters in each of four major biocompatibility categories were found to differ significantly between the three groups. RBC and FFP use, maximum platelet decrease and maximum WBC increase were each improved in the CM L group as compared to the other two groups. The results indicate that the CML offers distinct biocompatibility advantages over the other two systems in several important blood component categories. Despite the slight user friendliness advantages of a bubbler system, we believe that the oxygenator of choice at present is the CML.
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Affiliation(s)
- Barry J Zadeh
- The New York Hospital-Cornell University Medical Center, New York
| | - Rose Holazo
- The New York Hospital-Cornell University Medical Center, New York
| | - Cathy Conlon
- The New York Hospital-Cornell University Medical Center, New York
| | | | - O Wayne Isom
- The New York Hospital-Cornell University Medical Center, New York
| | - Karl H Krieger
- The New York Hospital-Cornell University Medical Center, New York
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Palatianos GM, Foroulis CN, Vassili MI, Astras G, Triantafillou K, Papadakis E, Lidoriki AA, Iliopoulou E, Melissari EN. A prospective, double-blind study on the efficacy of the bioline surface-heparinized extracorporeal perfusion circuit. Ann Thorac Surg 2003; 76:129-35. [PMID: 12842526 DOI: 10.1016/s0003-4975(03)00338-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND We evaluated the newly introduced Bioline heparin coating and tested the hypothesis that surface heparinization limited to the oxygenator and the arterial filter will ameliorate systemic inflammation and preserve platelets during cardiopulmonary bypass (CPB). METHODS In a prospective double-blind study, 159 patients underwent coronary revascularization using closed-system CPB with systemic heparinization, mild hypothermia (33 degrees C), a hollow-fiber oxygenator, and an arterial filter. The patients were randomly divided in three groups. In group A (controls, n = 51), surface heparinization was not used. In group B (n = 52), the extracorporeal circuits were totally surface-heparinized with Bioline coating. In group C (n = 56), surface heparinization was limited to oxygenator and arterial filter. RESULTS No significant difference was noted in patient characteristics and operative data between groups. Operative (30-day) mortality was zero. Platelet counts dropped by 12.3% of pre-CPB value among controls at 15 minutes of CPB, but were preserved in groups B and C throughout perfusion (p = 0.0127). Platelet factor 4, plasmin-antiplasmin levels, and tumor necrosis factor-alpha increased more in controls during CPB than in groups B or C (p = 0.0443, p = 0.0238 and p = 0.0154 respectively). Beta-thromboglobulin, fibrinopeptide-A, prothrombin fragments 1 + 2, factor XIIa levels, bleeding times, blood loss, and transfusion requirements were similar between groups. Intensive care unit stay was shorter in groups B and C than in controls (p = 0.037). CONCLUSIONS Surface heparinization with Bioline coating preserves platelets, ameliorates the inflammatory response and is associated with a reduced fibrinolytic activity during CPB. Surface heparinization limited to the oxygenator and the arterial filter had similar results as totally surface-heparinized circuits.
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Affiliation(s)
- George M Palatianos
- Third Department of Cardiac Surgery, Onassis Cardiac Surgery Center, Athens, Greece.
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4
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Kottke-Marchant K, Sapatnekar S. Hemostatic Abnormalities in Cardiopulmonary Bypass: Pathophysiologic and Transfusion Considerations. Semin Cardiothorac Vasc Anesth 2001. [DOI: 10.1053/scva.2001.26125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Cardiac surgical procedures typically use cardiopulmo nary bypass (CPB), a technique that diverts blood from the heart and lungs, where it is oxygenated and pumped back into the circulation. CPB is associated with significant pathophysiologic changes leading to an increased bleeding risk. Bleeding during CPB occurs for multiple reasons; the primary reason is the expo sure of blood to the material components of the CPB system, with intense systemic coagulation and platelet, fibrinolytic, and endothelial activation. To counteract the coagulation activation, extremely high levels of heparin anticoagulation are required to prevent sys temic thrombosis. Thrombin generation through tissue factor pathway activation is now thought to be the predominant mechanism of coagulation activation in CPB. The stimulus for tissue factor exposure to blood is thought to be a systemic activation of tissue factor on monocytes and endothelial cells caused by comple ment activation by the CPB materials and circulating inflammatory mediators. Despite improvements in the CPB system, surgical techniques, and blood conserva tion methods, the demand for blood in such procedures remains sustantial. Optimal blood use can be achieved by combining blood conservation measures with the transfusion of blood components according to strict guidelines. Blood is a limited resource and must be used wisely and cautiously. The risks and costs associ ated with transfusion are compelling reasons to mini mize unnecessary exposure to blood. However, the bene fits of transfusion are well established, and the risks are reasonably low. New developments in the surfaces of the CPB system, use of established and new protease inhibitors, and new blood conservation measures offer promise in decreasing the bleeding risk associated with CPB.
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Affiliation(s)
- Kandice Kottke-Marchant
- Department of Clinical Pathology, The Cleveland Clinic Foundation and American Red Cross Blood Services, Northern Ohio Region, Cleveland, OH
| | - Suneeti Sapatnekar
- Department of Clinical Pathology, The Cleveland Clinic Foundation and American Red Cross Blood Services, Northern Ohio Region, Cleveland, OH
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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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6
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Abstract
Exposure of blood to an extracorporeal circulation, such as CPB, causes a variety of physiological responses. Haematological derangements are just one of many potential dangers to the patient who undergoes CPB. The paradox of CPB-related problems with the haematological system is that there are some factors tipping the balance towards a bleeding tendency, and others that favour a prothrombotic state. Both of these issues must be dealt with independently to create the safest environment for surgery. It has been demonstrated that platelets play a key role in both haemostatic dysfunction and thrombotic complications of CPB. Much has been achieved, both clinically and in the laboratory, in the understanding of the precise role platelets play in these events, but the exact mechanisms involved have yet to be completely identified. As research progresses, our understanding will increase, but until then clinical practice must be dictated by the current evidence available.
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Affiliation(s)
- J A Hyde
- Department of Cardiothoracic Surgery, Queen Elizabeth Hospital, Birmingham.
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Affiliation(s)
- F W Campbell
- Department of Anesthesia, Hospital of the University of Pennsylvania, Philadelphia 19104-4283
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Martinowitz U, Goor DA, Ramot B, Mohr R. Is transfusion of fresh plasma after cardiac operations indicated? J Thorac Cardiovasc Surg 1990. [DOI: 10.1016/s0022-5223(19)35603-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Wasser MN, Houbiers JG, D'Amaro J, Hermans J, Huysmans HA, van Konijnenburg GC, Brand A. The effect of fresh versus stored blood on post-operative bleeding after coronary bypass surgery: a prospective randomized study. Br J Haematol 1989; 72:81-4. [PMID: 2786735 DOI: 10.1111/j.1365-2141.1989.tb07656.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
In a prospective study, 237 patients undergoing a primary coronary bypass operation were randomized to receive 2 units of fresh whole blood (study group) or stored (2-5 d) blood (control group) at the end of the extracorporeal circulation. Serious post-operative bleeding necessitating a re-thoracotomy occurred in 4.2% of all patients with an equal distribution over the two groups. Post-operative haemoglobin content and platelet counts were higher in the study group, but the differences were small and clinically not important. There were no differences in transfusion requirements, post-operative blood losses and haemostatic parameters between the trial groups. At low post-operative platelet counts (below 120 X 10(9) platelets/l) however, patients in the control group lost significantly more blood and had increased transfusion requirements compared with patients in the study group (7.1 versus 4.8 units). These differences must be attributed to qualitative platelet defects in the transfused units of stored blood. The small, clinically insignificant, differences in two laboratory parameters between the study and control groups, and the increased transfusion requirements of a subpopulation of patients with low platelet counts in the control group do not justify giving fresh blood or prophylactic platelet transfusions to coronary bypass patients.
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Affiliation(s)
- M N Wasser
- Department of Immunohaematology and Blood Bank, University Hospital, Leiden, the Netherlands
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Teoh KH, Christakis GT, Weisel RD, Wong PY, Vickie Mee A, Ivanov J, Mindy Madonik M, Levitt DS, Reilly PA, Rosenfeld JM, Glynn MF. Dipyridamole preserved platelets and reduced blood loss after cardiopulmonary bypass. J Thorac Cardiovasc Surg 1988. [DOI: 10.1016/s0022-5223(19)35281-x] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Spyt TJ, Wheatley DJ, Walker ID, Davidson JF, MacArthur K, Martin W. Placebo-controlled study of Iloprost (ZK 36374) in cardiopulmonary bypass surgery. Perfusion 1988. [DOI: 10.1177/026765918800300303] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The effects of infusion of Iloprost (ZK 36374), a prostacyclin analogue, on platelet function, postoperative blood loss and microaggregate deposition on filters and oxygenators were studied in patients undergoing routine coronary operations. In this double-blind randomized study of 50 male patients, 25 received Iloprost and 25 a placebo. Platelet deposition was assessed using Indium-labelled platelets. Comparison of Iloprost and placebo groups showed the mean number of platelets to be significantly higher in the Iloprost group at the end of cardiopulmonary bypass and in early postoperative recovery. Similarly, spontaneous aggregation of platelets was higher in the placebo group. The mean percentages of platelets sequestrated in the extracorporeal circuit were significantly higher in the placebo group. There was no difference in either the amount or pattern of postbypass bleeding between Iloprost and the control patients. Infusion of the tested drug was responsible for significant hypotension, which was correctable with fluid administration alone. Thus, Iloprost diminishes the fall in circulatory platelet count during cardiopulmonary bypass, preserves platelet function, diminishes platelet deposition on filters and oxygenators, but also causes arterial hypotension.
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Abstract
The contributions of platelets and clotting factors in thrombosis on injured vessel and cardiovascular prostheses have been quantified with several tracers. Thrombus formation in vivo could be measured semiquantitatively in animal models and humans with 111In-labeled platelets, 123I- and 131I-labeled fibrinogen, 111In-labeled antibody to the fibrinogen receptor on the platelet membrane and to fibrin. Thrombus localization by imaging was possible for large thrombus in vessel with deep injury of thrombogenic surface in the acute phase. A single layer of adherent platelet could not be imaged, due to the high background radioactivity present in blood. Thrombogenicity of graft was compared with that of contralateral vessel. The dynamic process of platelet deposition could be followed accurately using the in vivo imaging technique. In addition, in vitro quantification permits determination of platelet and fibrin density and of the number of fibrin monomers per platelet in thrombus. The roles of prostacyclin, thromboxane inhibitors, and nonsteroidal antiinflammatory drugs have also been evaluated in animals models and humans. The tracer techniques thus provide invaluable information about platelet-fibrin deposition, its organization and dissolution, and for development of less thrombogenic surfaces for use in cardiovascular prostheses.
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Affiliation(s)
- M K Dewanjee
- Section of Nuclear Medicine, Mayo Clinic, Rochester, Minnesota 55905
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15
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Teoh KH, Christakis GT, Weisel RD, Madonik MM, Ivanov J, Wong PY, Mee AV, Levitt D, Benak A, Reilly P. Blood conservation with membrane oxygenators and dipyridamole. Ann Thorac Surg 1987; 44:40-7. [PMID: 3300583 DOI: 10.1016/s0003-4975(10)62354-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Cardiopulmonary bypass induces platelet activation and dysfunction, which result in platelet deposition and depletion. Reduced platelet numbers and abnormal platelet function may contribute to postoperative bleeding. A membrane oxygenator may preserve platelets and reduce bleeding more than a bubble oxygenator, and the antiplatelet agent dipyridamole may protect platelets intraoperatively and reduce bleeding postoperatively. A prospective randomized trial was performed in 44 patients undergoing elective coronary artery bypass grafting to assess the effects of the membrane oxygenator and dipyridamole on platelet counts, platelet activation products, and postoperative bleeding. Patients who were randomized to receive a bubble oxygenator and no dipyridamole had the lowest postoperative platelet counts, the greatest blood loss, and the most blood products transfused. Platelet counts were highest and blood loss was least in patients randomized to receive a membrane oxygenator and dipyridamole (p less than .05). A bubble oxygenator with dipyridamole and a membrane oxygenator without dipyridamole resulted in intermediate postoperative platelet counts and blood loss. Arterial thromboxane B2 and platelet factor 4 concentrations were elevated on cardiopulmonary bypass in all groups. Both the membrane oxygenator and dipyridamole were independently effective (by multivariate analysis) in preserving platelets. Optimal blood conservation was achieved with a membrane oxygenator and dipyridamole.
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Amsterdam JT, Hedges JR, Engel PJ, Gabel M, Zumwalt R. Emergency bypass system: analysis of gas transfer. Am J Emerg Med 1987; 5:24-32. [PMID: 3814278 DOI: 10.1016/0735-6757(87)90284-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
A portable emergency bypass system using a membrane oxygenator device (CPS) was evaluated. The ability of the CPS to supply the oxygen transfer needs of five anesthetized dogs consistently over six hours and the system's effects on hemoglobin concentration, platelet count, and degree of hemolysis were assessed. The animals maintained spontaneous heart beats, pump flows averaged 100 ml/kg/min; mean arterial pressures were maintained at from 114 to 144 mm Hg. Immediate dilution of hemoglobin and platelet levels occurred in the first 30 minutes. Further hemodilution was limited during the first two hours, although three of the animals required transfusions during the six-hour period to maintain their hematocrits. Plasma free hemoglobin did not significantly increase during the six hours. Baseline oxygen consumption data obtained in three animals ranged from 44.5 to 96 (ml oxygen/min/m2). Oxygen and carbon dioxide transfer measurements during the first hour of bypass were not significantly different from measurements during the last hour of perfusion. The study suggests that optimal use of the CPS could supply much if not all of a patient's basal oxygen transfer requirements for at least six hours.
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Bagge L, Lilienberg G, Nyström SO, Tydén H. Coagulation, fibrinolysis and bleeding after open-heart surgery. SCANDINAVIAN JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY 1986; 20:151-60. [PMID: 3738446 DOI: 10.3109/14017438609106494] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
To investigate the disputed pathogenesis of excessive bleeding after open-heart surgery, variables representing different hemostatic systems were correlated to postoperative blood loss in 29 patients. The general bleeding tendency in the early postoperative phase was probably attributable to depletion of hemostatic agents due to hemodilution, decreased antiplasmin activity, instantaneous but reversible platelet dysfunction following protaminization, and the natural interval to development of complete hemostasis. Heavy bleeding (greater than 800 ml/16 h) occurred in ten patients, who had significantly reduced levels of von Willebrand factor and lower active platelet count than in eight patients with minor bleeding. Defective primary hemostasis thus seemed to be the main cause of increased postoperative bleeding in these patients. Determination of platelet function by glass retention test showed good clinical relevance and gave considerably more reliable diagnosis than conventional platelet count alone. The patient with the greatest blood loss also showed drastic decrease in the plasminogen-binding form of alpha 2-antiplasmin, suggesting that additionally impaired fibrinolysis inhibition may contribute to development of severe hemorrhagic complications.
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Lazar HL, Roberts AJ. Recent advances in cardiopulmonary bypass and the clinical application of myocardial protection. Surg Clin North Am 1985; 65:455-76. [PMID: 3898426 DOI: 10.1016/s0039-6109(16)43631-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Basic scientific research has provided the impetus to develop cardioplegic solutions that offer excellent myocardial preservation. Future research will continue to develop methods for better delivery of cardioplegia to all myocardial regions. In addition, earlier detection of evolving ischemic damage during aortic cross-clamping might provide a basis for earlier intervention to reverse developing myocardial injury. At the present time, the cardiac surgeon has many cardioplegic solutions and delivery systems from which to choose. Only by understanding the principles involved in myocardial preservation will the surgeon be able to develop a system that will work best in his or her clinical practice.
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Abstract
A comparative study of the thrombogenicity of several microporous membranes was performed using an ex vivo system simulating the conditions in an artificial lung. A study of platelet adhesion and adsorbed protein layer indicated that the membranes separated into three groups. Copolyurethane membranes adsorbed very few platelets and appeared to be most compatible; microporous polypropylene and polytetrafluoroethylene membranes were intermediate in their response; silicone rubber and silicone rubber-coated paper membranes showed numerous platelet clots, often involving neutrophils and fibrin, and were the least blood compatible.
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Abstract
The contribution of platelets in atherosclerosis and thrombosis in animal models and in clinical studies has been quantified with 111In-platelet scintigraphy. New in vitro quantitative techniques have been developed using 111In-labeled platelets to determine the number of adherent platelets on deendothelialized surfaces of damaged vessel walls and synthetic vascular grafts. In vivo imaging techniques are semi-quantitative in nature; in these studies 111In radioactivity on thrombotic vessels or graft surfaces of iliac, femoral, or popliteal arteries is compared with contralateral vessels. Background 111In radioactivity in the circulating blood pool of venous and capillary networks and radioactivity in marrow decreases the sensitivity of these techniques. Despite these limitations, the dynamic process of platelet deposition in most of the denuded, atherosclerotic vessels and prostheses in the circulatory system can be recorded. This ongoing thrombosis and embolization has been observed in 5-10-year-old vascular grafts of Teflon and Dacron biomaterials. Currently used platelet function inhibitor drugs, eg, aspirin, Persantine, sulfinpyrazone, and Motrin, have a demonstrable effect on platelet deposition. Slight changes in reduction of platelet deposition on these surfaces due to medical intervention have been observed by noninvasive imaging with 111In-platelets. Subtraction of blood pool radioactivity with 99mTc-labeled autologous red cells and calculation of 111In radioactivity associated with platelet thrombus on vessel walls also have been performed for coronary, carotid, and femoral arteries. Although platelet concentrates are used frequently after open heart surgery (one to six per patient), consumption of platelets in the artificial lung or oxygenator, lysis of platelets during pumping, and suction of blood only recently have been quantified with the use of 111In-labeled platelets. These studies also demonstrated far less trauma to platelets with the use of a membrane rather than a bubble oxygenator. Further reduction in platelet consumption and trauma was observed with the use of prostacyclin, a short-acting drug with significant beneficial effect on platelet thrombus reduction and disaggregation of aggregated platelets. The role of polymorphonuclear leukocytes in inflammation, infection and myocardial infarction, and in vivo evaluation with 111In-leukocyte scintigraphy in animals and humans has been described.(ABSTRACT TRUNCATED AT 400 WORDS)
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