Modified Ultrafiltration Attenuates Dilutional Coagulopathy in Pediatric Open Heart Operations

Background. Extreme hemodilution caused by relatively large prime volumes required for cardiopulmonary bypass in infants causes a dilutional coagulopathy, characterized by low concentrations of fibrinogen and other circulating coagulation factors. Modified ultrafiltration results in hemoconcentration and is associated with decreases in postoperative bleeding and transfusion requirements in children. This study was undertaken to quantify the effect of modified ultrafiltration on concentrations of fibrinogen, plasma proteins, and platelets in infants and small children.

Methods. Twenty patients less than 15 kg were studied. Cardiopulmonary bypass circuits were primed with crystalloid solutions. Red blood cells were added during cardiopulmonary bypass for hematocrits less than 15%. Colloid solutions were not administered. Concentrations of fibrinogen, plasma proteins, and platelets, and hematocrit were measured before cardiopulmonary bypass, before modified ultrafiltration, and after modified ultrafiltration.

Results. Modified ultrafiltration was associated with significant (p < 0.001) increases in hematocrit (19% ± 6% to 31% ± 9%), fibrinogen (65 ± 29 to 101 ± 45 mg/dL), and total plasma proteins (2.7 ± 0.3 to 4.9 ± 0.7 g/dL), but no change (p = 0.129) in platelet count.

Conclusions. We conclude that modified ultrafiltration significantly attenuates the dilutional coagulopathy associated with cardiopulmonary bypass in infants.     

酸血症时凝血功能变化的研究

目的 观察酸血症时凝血功能变化,对比不同检测方法对酸血症时凝血功能的诊断价值.方法 将12只家猪分为对照组和酸血症组,在控制性放出实验动物总血容量的35%后,阻断其自主呼吸并配合呼吸机制造酸血症模型.测定基础时间点和酸血症模型制作成功180 min后血浆凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)、凝血酶时间(TT)以及血栓弹力图仪(TEG)各项参数,并行对照分析.结果 与基础值相比,180 min后实验组血乳酸浓度上升了220%,血小板数量降低了30%,血浆纤维蛋白浓度降低了27%(P ＜0.05),实验组PT、APTT和TT均无显著变化.TEG各项参数中,R时间无显著变化,K时间出现显著延长,α角和MA值均显著减小(P＜0.05).结论 在酸血症时,实验动物出现血低凝状态,其原因与血凝块合成速率下降和血凝块强度的降低有关.TEG在创伤合并酸血症时对凝血功能检测的敏感性优于PT、APTT等方法.     

急性创伤性凝血病的研究进展

急性创伤性凝血病是创伤后发生率较高且后果较为严重的并发症之一,其死亡率高,较易发展为多器官功能衰竭。早期诊断和积极处理急性创伤性凝血病是急诊创伤外科治疗的重要内容,也是降低创伤死亡率的关键。本文就近期急性创伤性凝血病的流行病学资料、影响因素、病理生理机制和临床治疗等方面的研究新进展作一综述,希望为临床工作提供参考。     

Therapeutic plasma exchange in the management of sepsis and multiple organ dysfunction syndrome: A report of three cases

Sepsis with multi organ dysfunction syndrome (MODS) is the most common cause of death in patients in noncoronary intensive care units. Currently, there are no specific treatments that reduce mortality in patients with sepsis and MODS. We report three patients who received therapeutic plasma exchange (TPE) for sepsis with MODS who completely recovered. The first patient, a 3‐year‐old male presented with Methicillin‐resistant Staphylococcus aureus‐associated respiratory, renal, coagulation, hepatic, and neurologic dysfunction. After 5 TPEs, the patient fully recovered. The second patient was a 36‐year‐old pregnant female who developed MODS at 22 weeks of gestation. She had developed respiratory, hepatic, renal, cardiovascular, neurologic, and coagulation dysfunction following pneumonia and concurrent urinary tract infection resulting in an intrauterine fetal demise. After 8 TPEs, the patient was discharged home with only mild residual hepatic dysfunction. The third patient, a 50‐year‐old female with a history of seizure disorder, was found unresponsive in over 100°F heat and diagnosed with Staphylococcus aureus‐associated MODS. Her respiratory, coagulation, neurologic, renal, and hepatic systems were affected. The patient underwent 6 TPEs after which she had marked improvement. In conclusion, TPE may be an effective adjunct therapy in MODS by possibly removing toxic mediators and replacing deficient factors using donor plasma. J. Clin. Apheresis 29:127–131, 2014. © 2013 Wiley Periodicals, Inc.     

The incidence and magnitude of fibrinolytic activation in trauma patients

Summary. Background:  Trauma is a global disease, with over 2.5 million deaths annually from hemorrhage and coagulopathy. Overt hyperfibrinolysis is rare in trauma, and is associated with massive fatal injuries. Paradoxically, clinical trials suggest a much broader indication for antifibrinolytics. Objective: To determine the incidence and magnitude of fibrinolytic activation in trauma patients and its relationship to clot lysis as measured by thromboelastometry. Methods: A prospective cohort study of 303 consecutive trauma patients admitted between January 2007 and June 2009 was performed. Blood was drawn on arrival for thromboelastometry (TEM) and coagulation assays. Follow‐up was until hospital discharge or death. TEM hyperfibrinolysis was defined as maximum clot lysis of > 15%. Fibrinolytic activation (FA) was deterined according to plasmin–antiplasmin (PAP) complex and D‐dimer levels. Data were collected on demographics, mechanism, severity of injury, and baseline vital signs. The primary outcome measure was 28‐day mortality. The secondary outcome measures were 28‐day ventilator‐free days and 24‐h transfusion requirement. Results: Only 5% of patients had severe fibrinolysis on TEM, but 57% of patients had evidence of ‘moderate’ fibrinolysis, with PAP complex levels elevated to over twice normal (> 1500 μg L^?1) without lysis on TEM. TEM detected clot lysis only when PAP complex levels were increased to 30 times normal (P < 0.001) and antiplasmin levels were < 75% of normal. Patients with FA had increased 28‐day mortality as compared with those with no FA (12% vs. 1%, P < 0.001), fewer ventilator‐free days, and longer hospital stay. Conclusions: FA occurs in the majority of trauma patients, and the magnitude of FA correlates with poor clinical outcome. This was not detected by conventional TEM, which is an insensitive measure of endogenous fibrinolytic activity.     

State of the Art – How I manage coagulopathy in cardiac surgery patients

Over 35 000 cardiac operations using cardiopulmonary bypass are performed annually in the UK. Post‐operative bleeding is a common cause of morbidity. Although there have been improvements in surgical techniques, recent publications still show post‐operative blood loss to be significant, with allogeneic blood product usage as high as 50%. Despite greater understanding of the mechanisms of the coagulopathy encountered during cardiac surgery the development of treatment options has been slow. There has been a realization of the inadequacy of fresh frozen plasma to correct the coagulopathy in this setting, leading to greater off‐label use of specific factor concentrates to stop bleeding, e.g., prothrombin complex concentrates and fibrinogen concentrates. Recent trials using factor XIII and IX concentrates have not been successful. This article will review preventative measures to reduce post‐operative bleeding and the current management of bleeding with such factor concentrates and, in most cases, the limited evidence supporting their widespread use.     

Traumatic Lingual Hematoma Resulting in Bilateral Temporal Mandibular Joint Dislocations

Background

Lingual hematoma (LH) is a relatively uncommon entity seen after both medical and traumatic etiologies. Regardless of the cause, the feared complication is acute airway obstruction.