Hemostasis Laboratory: Assays for Platelet Function and Von Willebrand Disease

Journal of Thrombosis and Thrombolysis -     

Prolonged Holding of Whole Blood at 22 °C Does Not Increase Activation in Platelet Concentrates

Objectives: Platelets prepared after holding of whole blood overnight at 22 °C have a well-preserved metabolism. However, the possibility that such prolonged incubation with active granulocytes may increase platelet activation has not been fully tested. Methods: We investigated this possibility by flow cytometric analysis of membrane glycoproteins (GPs) Ib and IIb/IIIa and the activation markers CD62P and CD63 in platelet concentrates (PCs) prepared from whole blood that was held for either 6 h without cooling plates (n = 20) or for 24 h on cooling plates of 1,4-butanediol (n = 20). PCs were prepared by the platelet-rich plasma method and analyzed on the second storage day. Results: Platelet yield and aggregation response to ristocetin, collagen and epinephrine + ADP were similar in both types of PCs, as was the mean fluorescence intensity for GPs Ib and IIb/IIIa. PCs prepared by the overnight-hold method did not differ from those obtained 6 h after collection in the percentage of platelets expressing CD62P (12.3±6.2% vs. 14.1±4.0%; p > 0.1) or CD63 (9.8±6.4% vs. 8.8±3.6%; p > 0.1). Conclusion: Prolonged holding of whole blood at 22 °C prior to component preparation does not increase the level of platelet activation.     

“分离式”微温含血停跳液在心内直视手术中的应用

目的:探讨"分离式"微温(30～34℃)氧合自体血灌注心肌的保护方法在心内直视手术中的应用效果。方法:在226例心内直视手术中应用微温氧合自体血持续灌注的心肌保护方法,观察其临床效果。结果:体外循环结束时发生电解质紊乱13例,术后并发心律失常13例,经治疗后恢复;二次开胸止血8例;死亡2例,其余均痊愈出院,无低心排综合症,无脑、肝、肺、肾等重要器官并发症。结论:"分离式"微温血灌注心肌的方法具有理想的心肌保护效果,且操作简单方便,值得临床应用和推广的一种有效的心肌保护方法。     

Hæmostasis Disorders in Open Heart Surgery with Extracorporeal Circulation: Importance of the Platelet Function and the Heparin Neutralization

Abstract. The main haemostasis changes observed in a screening study performed in 40 patients who underwent an open heart surgery with extracorporeal circulation (ECC) are: a significant drop in platelet count from the onset of the ECC to the third postoperative day, a decrease of platelet retention and aggregation during ECC with an 8-day persistently increased heparin-neutralizing activity in plasma but not in serum, a moderate decrease of plasma factors I, II, VII-X, X and XIII and a more important drop in factor V which disappears 24 h after ECC, a transitory increase of fibrinolysis during ECC and the lack of FDP elevation in the serum. These disorders require a very good neutralization of the heparin used during ECC. The ratio protamine/heparin can be established by a titration clotting time test. Protamine chloride seems to be more efficacious and to act more quickly than protamine sulfate for the neutralization. An overload in protamine can enhance the hemostatic, biological and clinical disorders. The preventive administration of platelet concentrate immediately after the heparin neutralization contributes to reduce the bleeding disorders related to the quantitative and qualitative platelet defects.     

A Single Bout of High-Intensity Interval Exercise Does Not Increase Endothelial or Platelet Microparticles in Stable,Physically Fit Men With Coronary Heart Disease

Background

High-intensity interval exercise (HIIE) is gaining in popularity in fitness centres, even among coronary heart disease (CHD) patients. However, whether HIIE can have deleterious acute effects on the vasculature in CHD has not been studied. We hypothesized that when compared with moderate-intensity continuous exercise (MICE), a single bout of HIIE could lead to vascular damage and increasing numbers of circulating endothelial and platelet microparticles (EMPs, PMPs) in stable, physically fit CHD patients.

Methods

Nineteen male CHD patients (aged 62 ± 11 years) underwent, in random order, a single session of HIIE corresponding to 15-second intervals at 100% of peak power output and 15-second passive recovery intervals, and an isocaloric MICE session. EMPs (CD31⁺ and/or CD62E⁺ and CD42b⁻); PMPs (CD42b⁺); nitrates and nitrites; prostacycline; and troponin T, cardiac form (cTnT), were measured 10 minutes before exercise and 20 minutes, 24 hours, and 72 hours after both exercise sessions.

Results

EMPs, PMPs, nitrates and nitrites, prostacycline, and cTnT remained unchanged after both HIIE and MICE exercise sessions. Initial EMP concentration correlated inversely with EMP concentration 20 minutes post exercise, irrespective of exercise modality (r = 0.78, P < 0.0001).

Conclusions

A single HIIE session with very short exercise and passive recovery periods appears safe and does not induce changes to markers of endothelial function. Future studies are required to determine the safety of a long-term HIIE training program.     

New Strategies for Prevention and Treatment of Graft-versus-Host Disease and for Induction of Graft-versus-Leukemia Effects

Graft-versus-host disease (GVHD) continues to be a problem in allogeneic hemopoietic stem cell transplantation; however, our understanding of the basic pathophysiology of GVHD has improved. Although not all data obtained from murine or other animal models can be extrapolated to the clinic, there are leads that deserve to be pursued. The skin, intestinal tract, and liver are the 3 major target organs of GVHD and share the feature of presenting a barrier to the "environment" of the host. There is evidence that the damage inflicted to these organs, the epithelial and endothelial cells in particular, by the conditioning regimen causes a release of various cytokines and a penetration of endotoxin into the systemic circulation. According to these observations, the nonimmunologic aspects of GVHD have been likened to an inflammatory process. If this characterization is valid, blocking these nonspecific inflammatory changes would ameliorate GVHD without interfering with the graft-versus-leukemia (GVL) reaction. In fact, one study has shown a substantial amelioration of GVHD with a molecule that directly blocks endotoxin. Clinical data also suggest that patients with organ dysfunction early after transplantation that is presumed to be treatment related may benefit from preemptive interventions aimed at controlling GVHD. Furthermore, there is growing evidence that the mechanisms involved in GVHD may differ from organ to organ (for example, Fas/Fas-ligand interactions in the liver versus tumor necrosis factor alpha/receptor interactions in the intestinal tract), and from a therapeutic point of view, the time of onset of clinical GVHD may be important in choosing the appropriate therapy. Thus, combinations of interventions chosen and timed appropriately may be more effective in preventing and managing GVHD than are the standard across-the-board approaches that have been used so far. Such a strategy may also be successful in maintaining a GVL effect and possibly in incorporating direct antileukemic therapy, such as the use of cytotoxic T-cells directed at minor histocompatibility antigens, without increasing the risk of GVHD. The development of nonmyeloablative conditioning regimens and the observations on GVHD kinetics and the progression or eradication of leukemia with that strategy are likely to add new insights into how one can optimally combine various modalities to achieve engraftment, prevent GVHD, and at the same time maintain a GVL effect.     

Ambulatory Blood Pressure Monitoring in the Prediction and Prevention of Coronary Heart Disease

We reviewed studies of ambulatory blood pressure monitoring (ABPM) in patients with symptomatic coronary heart disease (CHD) or asymptomatic coronary lesions and in patients at high coronary risk, such as in the presence of hypertension. We identified ten cross-sectional and seven prospective studies in patients with CHD or coronary lesions. These studies showed that patients with CHD or coronary lesions often had nocturnal non-dipping or increased blood pressure variability, and might have increased risk of coronary events, due to either uncontrolled hypertension or treatment-induced hypotension identified by ABPM. We identified ten observational studies in hypertensive patients and normotensive subjects and five therapeutic trials in hypertension. These observational studies demonstrated that one or more ambulatory blood pressure components might provide predictive value for coronary events above and beyond clinic blood pressure. The therapeutic trials were less conclusive, but suggestive of additional value for the prevention of coronary events.     

Leukocyte Filtration Does Not Affect Lymphocyte Subpopulations and NK Cell Function in Recipients of Blood Transfusions

Background and objectives: The possible immunosuppressive action of blood transfusion has aroused great interest recently, particularly with respect to its effects on tumor growth and recurrence rate of malignant disease. Materials and methods: The effect of blood transfusion on lymphocyte subpopulations and NK cell function preoperatively and 6 months postoperatively was studied in 129 patients treated with elective surgery for colorectal malignancy. Forty-two patients (33%) received blood transfusions, 21 of them randomly allocated to receive leukocyte-depleted blood products. Investigation was by means of conventional laboratory methods. Results: In 21 patients receiving a median of 3 units of non-leukocyte-depleted blood products (NLD), a significant reduction in CD4+ lymphocytes (44% vs. 40%, p < 0.01) occurred. In contrast, no significant changes in CD4+ lymphocytes were observed in the 21 patients transfused with leukocyte-depleted blood products (LD). However, with respect to lymphocyte subpopulations and NK cell function, differences between the NLD and LD groups were not significant. There was a marginal decrease in HLA-DR+ lymphocytes in the NLD patients without a history of previous transfusion. Conclusions: There seems to be no major change in lymphocyte subpopulations and NK cell function 6 months after blood transfusion. Thus we cannot confirm our previous findings of a reduced number of CD20+ cells after blood transfusion.     

胸腔镜下与常规开胸房间隔缺损修补术临床对比分析

目的探讨常规正中胸骨开胸直视下与完全胸腔镜下房间隔缺损修补术对先天性房间隔缺损患者术后恢复的影响。方法先天性房间隔缺损患者30例,分为15例开胸组行常规正中胸骨开胸直视房间隔缺损修补术和15例胸腔镜组行完全胸腔镜下房间隔缺损修补术,记录临床疗效相关数据。结果胸腔镜组的手术时间、SICU气管插管时间、术后住院时间和术后胸腔引流量均明显少于开胸组(均P0.05),且术后4周恢复工作者的比例与开胸组比较差异具有统计学意义(P0.05)。两组患者术后均无死亡或严重并发症的出现。术后随访3个月两组均无残余分流等异常情况。结论完全胸腔镜下房间隔缺损修补术的手术损伤较小,临床疗效较为理想,更有助于患者术后恢复。     

替格瑞洛对经皮冠状动脉介入治疗的冠心病患者凝血功能及血小板聚集率的影响研究

目的探究替格瑞洛对经皮冠状动脉介入治疗(PCI)的冠心病患者凝血功能及血小板聚集率(MPAR)的影响。方法选取2013年西安市中心医院收治的行PCI的冠心病患者197例,按照患者住院号尾数奇偶分为氯吡格雷组98例与替格瑞洛组99例。两组患者均接受常规治疗,氯吡格雷组在此基础上给予氯吡格雷治疗,替格瑞洛组在此基础上给予替格瑞洛治疗。观察两组患者治疗前后凝血四项〔凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)、凝血酶时间(TT)、纤维蛋白原(FIB)〕及MPAR。结果治疗前两组患者PT、APTT、TT、FIB、MPAR比较,差异无统计学意义(P0.05);治疗后替格瑞洛组PT、APTT短于氯吡格雷组,FIB、MPAR低于氯吡格雷组,TT长于氯吡格雷组(P0.05)。结论替格瑞洛能可有效改善行PCI的冠心病患者的凝血功能,降低MPAR。     

经皮冠状动脉介入治疗患者血小板功能检测的临床应用现状与展望

经皮冠状动脉介入治疗术后抗血小板治疗是预防主要不良心脏事件的重要措施。为了评估抗血小板治疗的疗效,指导抗血小板药物的应用,研究出了多种血小板功能检测方法,并在临床上广泛应用。理想的血小板功能检测应该能够：（1）指导个体化抗血小板治疗;（2）预测主要不良心血管事件;（3）评估出血风险。现就目前常用检测方法的有效性和局限性以及未来的发展方向作一综述。     

参麦注射液治疗冠心病的临床疗效及其对血小板聚集率、血小板聚集时间的影响

目的探讨参麦注射液治疗冠心病的临床疗效及其对血小板聚集率、血小板聚集时间影响。方法选取2013年5月—2015年4月湖南省第二人民医院收治的84例冠心病患者,按照随机数字表法将患者分为观察组和对照组,各42例。对照组患者给予常规治疗联合曲美他嗪治疗,观察组患者在对照组基础上加用参麦注射液治疗;两组患者均治疗4周。比较两组患者临床疗效,治疗前后血小板聚集率、血小板聚集时间及血清炎性因子〔超敏C反应蛋白(hs-CRP)、白介素6(IL-6)、白介素8(IL-8)〕水平。结果观察组患者临床疗效优于对照组(u=4.13,P0.05)。治疗前两组患者血小板聚集率及血小板聚集时间比较,差异无统计学意义(P0.05);治疗后观察组患者血小板聚集率低于对照组,血小板聚集时间长于对照组(P0.05)。治疗前两组患者血清hs-CRP、IL-6、IL-8水平比较,差异无统计学意义(P0.05);治疗后观察组患者血清hs-CRP、IL-6、IL-8水平均低于对照组(P0.05)。结论参麦注射液治疗冠心病的临床疗效确切,能有效改善血小板聚集功能,降低血小板聚集率,减轻炎性反应。     

A Novel Patent Hemostasis Protocol - Prevention of Pseudoaneurysm after Tibiopedal Arterial Access for Evaluation and Treatment of Peripheral Arterial Disease

BackgroundPseudoaneurysm (PSA) is a rare complication (0.2%) after transpedal arterial access (TPA) for endovascular treatment of peripheral arterial disease, occurring only in the posterior tibial artery (PTA) likely related to the anatomy of the vessel leading to unfavorable circumstances for adequate hemostasis. We describe a novel patent hemostasis protocol for TPA access to avoid PSA.MethodsWe prospectively studied 586 patients with symptomatic PAD who underwent 1038 peripheral procedures between 02/2016 and 02/2017 via TPA (dorsalis pedis artery (DP)/anterior tibial artery (ATA), PTA or peroneal artery (PA)). Hemostasis for the DP/ATA was achieved with the Vasostat™ device, while TR Band™ was used for PTA/PA, as per our new protocol (figure). Patent hemostasis technique was confirmed using Doppler.ResultsOf the 1038 procedures, 733 (88% interventional) were done via the DP/ATA, 176 (92% interventional) were done via the PTA and 129 (64% interventional) were via the PA. The incidence of PSA related to any access site was 0.0%. All access sites were patent on Doppler ultrasound at 30 day follow up.ConclusionPSA associated with TPA is very rare, it can be easily prevented with the above described patent hemostasis protocol while preserving the patency of the access site.Condensed abstractPseudoaneurysm (PSA) is a rare complication (0.2%) after transpedal arterial access (TPA). We describe a novel patent hemostasis protocol for TPA access to avoid PSA. We prospectively studied 586 patients with symptomatic PAD who underwent 1038 endovascular procedures via TPA (dorsalis pedis artery (DP)/anterior tibial artery (ATA), PTA or peroneal artery (PA)). Hemostasis for the DP/ATA was achieved with the Vasostat™ device, while TR Band™ was used for PTA/PA, as per our new protocol (figure). Patent hemostasis technique was confirmed using Doppler. The incidence of PSA related to any access site was 0.0%. All access sites were patent on Doppler ultrasound at 30 day follow up. PSA associated with TPA is very rare, it can be easily prevented with the above described patent hemostasis protocol while preserving the patency of the access site.     

Single-Dose Daily Infusion of Cyclosporine for Prevention of Graft-versus-Host Disease after Allogeneic Bone Marrow Transplantation from HLA Allele-Matched, Unrelated Donors

Peak blood concentration of cyclosporine (CsA) in renal transplantation patients was recently reported to be associated with clinical efficacy. We therefore evaluated the toxicity and efficacy of a regimen of once-daily infusion of CsA plus a short course of methotrexate as prophylaxis of graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation from an HLA allele-matched, unrelated donor. Nineteen patients with hematologic malignancies received CsA, 3 mg/kg per day, as a 4-hour intravenous (IV) infusion from day -1. After engraftment, patients received CsA orally at twice the IV dose. The CsA dose was adjusted to maintain the blood trough level between 150 and 200 ng/mL. Methotrexate was administered IV at doses of 10 mg/m(2) on day 1 and 7 mg/m(2) on days 3, 6, and 11. Bone marrow engraftment occurred in all patients. Grade 1 and grade 2 GVHD occurred in 6 (31.6%) and 7 (36.8%) of the 19 patients, respectively. No patient had grade 3 or 4 GVHD. Acute nephrotoxicity developed in 1 (5.3%) of the 19 patients, and hypertension developed in 3 (15.8%) of the 19 patients. We evaluated the pharmacokinetics of 4-hour CsA infusion in 10 patients. The mean trough concentration, mean peak concentration, mean time to peak concentration, and area under the curve (24 hours) were 161 +/- 43 ng/mL, 1498 +/- 387 ng/mL, 3.2 +/- 1.0 hours, and 10,848 +/- 1,991 ng +/- h/mL, respectively. This regimen was well tolerated and did not enhance the risk of severe GVHD in patients undergoing allogeneic bone marrow transplantation from an HLA allele-matched, unrelated donor.     

监测脑血流在诊断先天性心脏病婴儿围手术期脑损伤中的应用

目的:通过监测体外循环过程中脑血流变化,研究其与脑损伤生化学指标的相关性,探讨脑血流降低在婴儿先天性心脏病(先心病)体外循环围手术期脑损伤中的应用.方法:对31例接受中低温全流量体外循环心脏手术的先心病患儿进行体外循环前后经颅多普勒脑血流监测,同时记录主动脉阻断时间.术前、术中、术后多时点测定脑损伤标记物S100B 蛋白(S100B)和神经元特异性烯醇化酶(NSE)数值.对全组患儿进行围手术期神经系统功能评价.应用多元线性回归分析,对术中脑血流变化、体外循环时间与脑损伤标记物测定值进行相关性分析.并初步探讨脑血流变化与术后神经系统异常之间的相关性.结果:本组患儿主动脉阻断时间为(60.72±28.72)min,主动脉阻断期间术中大脑中动脉脑血流流速稳定后的平均流速/术前麻醉后的大脑中动脉平均流速(Vm%)为(56±18)%.相关性分析表明,主动脉阻断时间与体外循环结束时点(Tc),术后6 h(T6),术后12 h(T12),术后24 h(T24) 时点的S100B值呈正相关(r=0.510,P=0.003;r=0.538,P＝0.002;r=0.469,P＝0.007;r=0.403,P=0.022),脑血流变化率与Tc、T6时点S100B值呈负相关(r=-0.368,P=0.038;r=-0.482,P=0.005);多元线性回归分析表明主动脉阻断时间与Tc及T12时点的S100B显著正相关(t=2.221,P＝0.035;t=2.163,P＝0.039).Vm%与T24时点的NSE呈负相关(r=-0.449,P=0.010);多元线性回归分析表明Vm%与T12时点的NSE显著负相关(t=-2.136,P＝0.042).全组31例患儿中,12例出现术后神经系统异常体征,Vm%＜50%患儿术后神经系统阳性体征的发生率较Vm%≥50%患儿明显增高,差异有统计学意义(P＝0.029).结论:体外循环过程中脑血流流速降低可能导致神经系统损伤,临床应用经颅多普勒监测围手术期脑损伤具有一定的实用价值.     

Fish Oil for Primary and Secondary Prevention of Coronary Heart Disease

Fish consumption and fish oils rich in omega-3 fatty acids were reported to be cardioprotective in both retrospective and prospective studies undertaken over the past two to three decades. In the past several years, there is mounting clinical trial data as well as basic science information supporting the use of fish oil supplements in both primary and secondary cardiovascular prevention. In addition, there appear to be additional benefits to the use of fish oil, including lowering significantly elevated triglyceride levels, preventing atrial fibrillation, reducing mortality rates in congestive heart failure patients, and perhaps stabilizing atherosclerotic plaques. These data have led to specific recommendations for use of omega-3 fatty acids in several cardiovascular areas.     

Incidence and Related Risk Factors of Junctional Ectopic Tachycardia in Infants after Cardiac Surgery for Congenital Heart Disease

Objective: Junctional ectopic tachycardia is common after cardiac surgery for congenital heart disease. However, its incidence and related risk factors in infants after cardiac surgery are not well known. The objective of this study was to determine the overall incidence and related risk factors for junctional ectopic tachycardia in neonates and infants. Methods: We enrolled a total of 271 patients aged <1 year who underwent open cardiac surgery at Severance Cardiovascular Hospital from January 2018 to December 2020. Exclusion criteria were immediate postoperative mortality, other arrhythmias detected in the perioperative period, and prematurity. Result: The overall incidence of junctional ectopic tachycardia was 12.9%. The logistic regression analysis revealed that longer cardiopulmonary bypass time, surgery involving atrioventricular node stretching, and the presence of early repolarization on preoperative electrocardiography increased the risk of junctional ectopic tachycardia. Patients with junctional ectopic tachycardia had longer intubation time and intensive care unit stay. Conclusion: Junctional ectopic tachycardia is a common arrhythmia after cardiac surgery for congenital heart disease in infants. Occasionally, infants developing junctional ectopic tachycardia after cardiac surgery have specific preoperative electrocardiography findings. The risk factors for junctional ectopic tachycardia were associated not only with surgical procedural factors but also with preoperative electrocardiographic parameters.     

围术期平衡针促醒重型颅脑损伤术后患者的非随机对照研究

目的 探讨围术期平衡针对重型颅脑损伤术后昏迷患者的促苏醒治疗的可行性.方法 采用非随机对照临床观察研究方法.重型颅脑损伤术后昏迷患者30例分为治疗组(n=15)和对照组(n=15).对照组采用常规治疗,治疗组在常规治疗基础上加用平衡针治疗.两组患者分别于治疗前,治疗后1疗程、2疗程、3疗程进行格拉斯哥昏迷量表(Glasgow Coma Scale,GCS)评分.结果 两组患者在术后治疗1个疗程,GCS评分治疗组与治疗前比较差异有统计学意义(P<0.05),对照组与治疗前比较差异无统计学意义(P>0.05);术后治疗3个疗程,GCS评分治疗组与对照组比较差异有统计学意义(P<0.05).结论 提示平衡针治疗对重型颅脑损伤术后昏迷患者可能有促苏醒作用,从而缩短患者昏迷时间.     

The Influence of Congenital Heart Disease on Psychological Conditions in Adolescents and Adults after Corrective Surgery

Objective. The present study was designed to examine psychological characteristics of adolescents and adults with operated congenital heart disease (ACHD). Particularly it was to be examined whether cardiological parameters may be associated with subjectively perceived impairments and measures of psychological distress. Patients. A total of 361 men (209) and women (152) between 14 and 45 years underwent medical checkups and an interview on psychological and sociological issues. Setting. The medical part consisted of a complete cardiological examination including the classification of residual symptoms according to the New York Heart Association (NYHA), and spiroergometry. The Brief Symptom Inventory was used for depicting current psychological and somatic symptoms. These were assessed on 9 subscales: somatization, obsession‐compulsion, interpersonal sensitivity, depression, anxiety, hostility, phobic anxiety, paranoid ideation, and psychoticism. Results. The analyses revealed statistically significant associations between the degree of NYHA class and psychological symptoms. These findings could not be reproduced for physical fitness as measured by peak oxygen consumption. No gender differences emerged. Conclusions. Our results suggest that psychological measures of ACHD are not directly dependent on their physical fitness or on the severity of residual symptoms. Instead, patients’ subjective appraisal of their disease severity and the conviction to what degree one can depend on the operated heart may be important determinants of psychological states.