Patients with heparin-induced thrombocytopenia have a poor prognosis and high mortality, thus surgical risk under extracorporeal circulation increased. Early diagnosis, safe and effective alternative anticoagulation strategy are crucial for these patients to receive extracorporeal circulation surgery. This review focuses on the pathophysiology, laboratory examination, diagnosis and alternative anticoagulation strategy of extracorporeal circulation for patients with heparin-induced thrombocytopenia.
Perioperative monitoring of blood coagulation is critical to better understand causes of hemorrhage, to guide hemostatic therapies, and to predict the risk of bleeding. Point-of-care (POC) coagulation monitoring devices assessing the viscoelastic properties of whole blood may overcome several limitations of routine coagulation tests in the perioperative setting. The advantage of these techniques is that they have the potential to measure the clotting process, starting with fibrin formation and continue through to clot retraction and fibrinolysis at the bedside, with minimal delays. Furthermore, the coagulation status of patients is assessed in whole blood, allowing the plasmatic coagulation system to interact with platelets and red blood cells, and thereby providing useful additional information on platelet function. Viscoelastic POC coagulation devices are increasingly being used in clinical practice, especially in the management of patients undergoing cardiac and liver surgery, assessment of hypo-and hypercoagulable states, guiding pro- and anticoagulant therapies, monitoring of antiplatelet therapy and procoagulant therapy. To ensure optimal accuracy and performance, standardized procedures for blood sampling and handling, strict quality controls and trained personnel are required.
Abstract: There is a 1% - 4% incidence of cardiac disease in pregnancy, and rheumatic heart disease is the most common diagnosis. On the condition that medical treatment is inefficacious, an open heart surgery should be performed. Because of the changes in physiological functions, there is a major difference between pregnant patients and the general population in perioperative management of valve replacement. Now , the pregnancy is not an absolute contraindication for cardiopulmonary bypass, though the incidence of mortality and birth defects remains high. It is helpful in decreasing complications and increasing survival rate by improving themethods of cardiopulmonary bypass, postoperative monitoring, anticoagulation etc. In this article, the progress in t reatments of perioperative period of cardiac valve replacement during pregnancy is reviewed.
Cardiopulmonary bypass(CPB) is associated with thrombocytopenia and platelet dysfunction. The primary cause of acquired platelet defect is thought to be activation and release of alpha granules during CPB. Before CPB, platelet-rich plasma (PRP) was prepared by obtaining the required amount of patient’s whole blood by autologous plateletpheresis. PRP could be reinfused after operation in order to protect the function and quantities of the platelets. On the other hand, PRP could be made into autologous platelet gel (APG). APG contains supraphysiologic amounts of growth factors, and has adequate tensile strength and adhesive ability. Therefore, it can be used for hemostasis in operation, sealing wound and enhancing incision or dehiscent sternal wounds healing.
Objective To investigate the trends of cardiopulmonary bypass （CPB） professional development and personnel constitution in the past five years in China， and provide prediction and advice for the trend of Chinese CPB personnel constitution in the future. Methods We conducted 2 questionnaire investigations of Chinese hospitals in which cardiovascular surgeries were performed in the year 2005 and 2010， regarding the number of on-pump and off-pump cardiovascular operations and cases of extracorporeal membrane oxygenation （ECMO）. Data of CPB personnel constitution in the year 2005 and 2010 were analyzed. Results The total number of cardiovascular operation， on-pump cardiovascular operation and ECMO cases was 104 631， 86 155， and 68 respectively in 2005. The total number of cardiovascular operation， on-pump cardiovascular operation and ECMO cases was 170 547， 136 753， and 206 respectively in 2010. There were 708 CPB professionals in 2005， including 40.2% （285/708）full time perfusionists and 23.2% （164/708）perfusionists with senior professional titles. There were 2 111 CPB professionals in 2010， including 37.6% （793/2 111） full time perfusionists and 25.5% （539/2 111） perfusionists with senior professional titles. Conclusion There has been a rapid CPB professional development in the past five years in China. The proportion of full time perfusionists， perfusionists with senior professional titles and higher educational degree will further increase in the future.
Objective To investigate the effect of polyethylene glycolbovine hemoglobin (PEG-bHb), which was used as an oxygen carrier in cardioplegic solution, on the protection of isolated rat hearts. Methods The hearts of 32 male SD rats were harvested and transferred to Langendorff circuit. They were divided into 4 groups according to cardiocplegia: St.Thomas group (group A), 1∶2 PEG-bHb group (group B), 1∶4 PEG-bHb group (group C) and 1∶8 PEG-bHb group (group D). After 20min balance period, hearts were perfused with cold (4℃) cardioplegic solutions, and preserved at 30℃ for 60min, then reperfused. Levels of cardiac troponin I (cTn I) and adenosine triphosphate(ATP) contant in coronary effuent were detected, and ultrastructures of myocardium were observed. Results After reperfusion, cTn I contant of group A were higher (F=52.955,Plt;0.05) and ATP contant were lower (F=68.757,Plt;0.05) than those in group B, group C and group D. Myocardial water contant were lower in group B and group C(F=3.048,Plt;0.05). Conclusion PEG-bHb in cardioplegic solutions can provide better myocardial protection during ischemia.
Abstract： Objective To observe myocardial protective effect of sevoflurane used in the whole process of cardiopulmonary bypass（CPB）. Methods A total of 150 patients older than 18 years who underwent cardiac surgery under CPB in Fu wai Hospital from January 2010 to November 2011 were enrolled in this double-blind and randomized controlled study. All the patients were randomly divided into three groups：Sevoflurane pretreatment group （Group A，n=50），whole-process Sevoflurane group （Group B，n=50），and whole-process intravenous anesthesia group （Group C，n=50）. Radial artery pressure and other hemodynamic parameters were continuously measured for all the patients. At following time points: CPB beginning （T1），aortic declamping （T2），3 hours after aortic declamping （T3），and 24 hours after aortic declamping （T4），serum concentrations of cardiac troponin I （cTnI） and other parameters were measured by enzyme-linked immunosorbent assay （ELISA）. Results There were 31 males and 19 females at age of 60.43±3.24 years in group A，28 males and 22 females at age of 59.88±4.12 years in group B，31 males and 19 females at age of 58.76±3.87 years. There was no statistical difference in mean arterial pressure （MAP），central venous pressure （CVP），pulmonary artery wedge pressure （PAWP） and heart rate （HR） at respective time points among the 3 groups （P＞0.05）. At T1 and T2，there was no statistical difference in cardiac index （CI） among the 3 groups （P＞0.05）. At T3，there was no statistical difference in CI between Group A and Group C（F=3.382，P=0.845），but CI of Group B was significantly higher than that of Group A and C（F=3.382，3.382； P=0.033，0.020）. At T4，CI of Group B was significantly higher than that of Group A and C （F=13.324，13.324； P=0.005，P=0.000），and CI of Group A was significantly higher than that of Group C （F=13.324，P=0.024）. At T1 and T2，there was no statistical difference in serum concentrations of creatinine kinase MB （CK-MB），cTnI，interleukin-6 （IL-6） and tumor necrosis factor alpha （TNF-α） among the 3 groups （P＞0.05）. At T3 and T4，serum concentrations of CK-MB，TNF-α，IL-6 and cTnI of Group C were significantly higher than those of Group A，and serum concentrations of CK-MB，TNF-α，IL-6 and cTnI of Group A were significantly higher than those of Group B （F=531.616，5.410，3.5813，3.160，1.126，4.702，7.819，5.424，all P=0.000）. Conclusion Sevoflurane used in the whole process of CPB has definite myocardial protective effect which is ber than that of Sevoflurane pretreatment.
Abstract： Objective To observe the expression changes of microRNA 1 （miRNA-1） and microRNA 21（miRNA-21） after ischemic preconditioning （IPC）, ischemic postconditioning （IPO） and remote ischemic preconditioning （RIPC）in an ischemia-reperfusion rat heart model in vitro, as well as the expression of their target protein heat shock protein 70 （HSP70） and programmed cell death 4 （PDCD4）, and evaluate whether miRNA are involved in endogenous cardio-protective mechanism. Methods The Langendorff-perfused Sprague-Dawley rat hearts were randomly assigned into one of the four groups, control group （CON group, n=12）, ischemia preconditioning group （IPC group， n=12） , ischemia postconditioning group （IPO group， n=12） and remote ischemia preconditioning group （RIPC group，n=12）. Cardiac function was digitalized and analyzed. The expression of HSP70, PDCD4, B-cell lymphoma/leukemia-2 （Bcl-2） and Bax was detected by Western blotting. The expression of miRNA-1 and miRNA-21 was detected by real-time reverse transcriotion-polymerase chain reaction （RT-PCR）. Assessment of cardiac infarct size and myocardial apoptosis was determined using triphenyltetrazolium chloride （TTC） assay and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay （TUNEL） assay respectively. Results The expressions of miRNA-1 and miRNA-21 were up-regulated in IPC group, but the expression of miRNA-1 was down-regulated in RIPC group and IPO group （P＜0.05）. The expressionsof PDCD4, HSP70 and Bax were down-regulated in ‘conditioning’ groups compared with CON group （P＜0.05）. The expression of Bcl-2 was not statistically different among the four groups. The infarct size and the myocardial apoptosis in ‘conditioning’ hearts were significantly decreased compared with CON group （P＜0.05）. Conclusion The expressions of the miRNA-1 and miRNA-21 are different in IPC, RIPC and IPO groups, and their target proteins are not inversely correlated with the miRNAs in all the ‘conditioning’ groups.
Objective To introduce a novel approach using parallel placement of another oxygenator in the recirculation line as oxygen supply for oxygenator failure without circulatory arrest in cardiopulmonary bypass （CPB），and confirm its outcomes in an animal experiment. Methods A traditional piglet CPB model was established. Oxygenator failure model was established by reducing fraction of inspired oxygen （FiO2） from 80% to 21% after aortic cross-clamp and cardiac arrest in CPB. Another oxygenator was then parallel placed in the recirculation line to supply 100% oxygen.Dynamic changes in partial pressure of oxygen （PaO2），mixed venous oxygen saturation （SvO2），arterial oxygen saturation（SaO2） and blood pH of blood samples from the arterial perfusion duct were monitored with different blood flow of400 ml/min，800 ml/min and 1 100 ml/min. Results When FiO2 was reduced to 21%，PaO2 decreased to 64-67 mm Hg（P＜0.001），SaO2 decreased significantly to 88%-90% （P＜0.001），SvO2 decreased to 69%-72% （P＜0.001），and blood pH decreased too，all indicating oxygenator failure. After parallel placement of another oxygenator in the recirculation line was performed，PaO2，SaO2 and SvO2 all significantly increased，as well as blood pH. When the blood flow in the recirculation line achieved 33% or above of overall arterial perfusion flow，clinical oxygen demand was generally satisfied. Conclusion Parallel placement of another oxygenator in the recirculation line may be utilized as a treatment strategy for oxygenator failure without circulatory arrest and changeover of failed oxygenator.