Coagulation In Patients Research Articles

O-027 Pathological Analysis Of Extracted Clots In Embolectomy Patients With Acute Ischaemic Stroke

BackgroundAn increasing number of acute ischaemic stroke patients are being treated with embolectomy devices. A pathological analysis of these extracted “clots” may be important in understanding device behaviour and procedure...

Raman spectroscopy for clinical-level detection of heparin in serum by partial least-squares analysis

Heparin is the most widely used anti-coagulant for the prevention of blood clots in patients undergoing certain types of surgeries including open heart surgeries and dialysis. The precise monitoring of heparin amount in patients' blood is crucial for reducing the morbidity and mortality in surgical environments. Based upon these considerations, we have used Raman spectroscopy in conjunction with partial least squares (PLS) analysis to measure heparin concentration at clinical level which is less than 10 United States Pharmacopeia (USP) in serum. The PLS calibration model was constructed from the Raman spectra of different concentrations of heparin in serum. It showed a high coefficient of determination (R2>0.91) between the spectral data and heparin level in serum along with a low root mean square error of prediction ~4 USP/ml. It enabled the detection of extremely low concentrations of heparin in serum (~8 USP/ml) as desirable in clinical environment. The proposed optical method has the potential of being implemented as the point-of-care testing procedure during surgeries, where the interest is to rapidly monitor low concentrations of heparin in patient's blood.

Commercialization of a Stroke Device: The Merci Retriever®

Treatment of ischemic stroke has improved greatly over the years with the development of medical devices to remove blood clots. We describe the background of development and commercialization activities of the first medical device approved in the United States to remove blood clots in patients who are experiencing an acute ischemic stroke, The Merci Retriever. Next generation devices known as Stentrievers look to improve efficacy and ease of use over previous devices.

Deep vein thrombosis in a patient of Sheehan′s syndrome: Autoimmunity or hypercoagulabilty

Introduction:Literature is inconsistent whether patients with hypopituitarism have increased risk of thrombosis. Recent data has shown problems with the coagulation system in Sheehan's syndrome (SS). Here, we describe a case of SS which presented with deep vein thrombosis.Objective:To describe a case of SS presenting as deep vein thrombosis.Case Report:A 30-year-old female was admitted to the general medicine ward with 1 month history of gradual onset swelling and pain in the left leg. The left calf diameter was 5 cm greater than the right. Doppler of the lower limbs revealed thrombosis in the left popliteal vein. Patient's coagulation profile revealed a normal prothrombin time of 12 sec, activated partial thromboplastin time of 30 sec, positive D-dimer, negative protein C and protein S and normal titres of antinuclear antibodies. Echocardiography showed an ejection fraction of 52 percent. Endocrinology consultation was sought in view of clinical suspicion of hypothyroidism. Endocrinology review revealed a significant past history of primary postpartum hemorrhage, lactation failure and secondary amenorrhea since the delivery of the last child 6 years back. She had clinical features of growth hormone, thyroid hormone and adrenocorticotropic hormone deficiency. Hormonal analysis showed features of central hypothyroidism, secondary adrenal insufficiency and growth hormone deficiency which was subsequently confirmed by insulin tolerance test.Conclusion:SS patients may have increased risk of thrombosis

Resuscitation and transfusion management in trauma patients

Severe trauma is associated with hemorrhage, coagulopathy and transfusion of blood and blood products, all associated with considerable mortality and morbidity. The aim of this review is to focus on resuscitation, transfusion strategies and the management of bleeding in trauma as well as to emphasize on why coagulation has to be monitored closely and to discuss the rationale of modern and future transfusion strategies. Coagulopathy and uncontrolled bleeding remain leading causes of death in trauma, lead to blood transfusions and increased mortality as it has been recently shown that blood transfusion per se results in an adverse outcome. In the last years, damage control resuscitation, a combination of permissive hypotension, hemostatic resuscitation and damage control surgery, has been introduced to treat severely traumatized patients in hemorrhagic shock. Goals of treatment in trauma patients remain avoiding metabolic acidosis, hypothermia, treating coagulopathy and stabilizing the patient as soon as possible. The place of colloids and crystalloids in trauma resuscitation as well as the role of massive transfusion protocols with a certain FFP : RBC ratio and even platelets have to be reevaluated. Close monitoring of bleeding and coagulation in trauma patients allows goal-directed transfusions and thereby optimizes the patient's coagulation, reduces the exposure to blood products, reduces costs and may improve clinical outcome.

Efficacy of Maixuekang capsule on reconvalescents of cerebral infarction and its impact on coagulation function

To observe the clinical efficacy of Maixuekang capsule in reconvalescents of cerebral infarction and its impact on coagulation function. One hundred and twenty cases of reconvalescents of cerebral infarction were randomly divided into treatment and control groups. The 50 cases in the control group were provided with conventional therapy, while the 70 cases in the treatment group were provided with the combination of conventional therapy and Maixuekang capsule for 3 months. Their neurological function and prothrombin time (PT), activated partial thromboplastin time (APTT) clotting enzyme time (TT), fibrinogen (Fib) were measured before and after treatment. After the treatment, PT, APTT and TT were prolonged compared with those before the treatment in the treatment group (P<0.05), whereas Fib, neurological deficit scores decreased (P<0.01) and significantly different from the control group (P<0.05). Maixuekang capsule is among safe and effective drugs in treatment of reconvalescents of cerebral infarction, and can improve the patient's coagulation state.

Rivaroxaban to Prevent Pulmonary Embolism After Hip or Knee Replacement

Rivaroxaban (Figure 1) is a new oral prescription medication used to help prevent clots from forming. Rivaroxaban is marketed under the brand name Xarelto, and it is approved in the United States, Canada, and Europe to prevent blood clots in patients undergoing an elective hip or knee replacement and to prevent stroke from atrial fibrillation. This Cardiology Patient Page will discuss the use of rivaroxaban to prevent pulmonary embolism and deep vein thrombosis after hip or knee replacement. Figure 1. Rivaroxaban (Xarelto) 10-mg tablets. Although there are many risk factors for developing a blood clot after surgery, one of the biggest is being immobile after surgery. Patients are at risk for developing a blood clot up to 3 months after surgery. Anticoagulants or “blood thinners” prevent blood clots from forming after surgery. Although these medications do not actually “thin” your blood, they make it more difficult for blood to clot. Proteins, called clotting factors, and platelets, a type of blood cell, are normally found flowing through your blood vessels. When you have a cut or when you are not moving and your blood becomes sluggish, clotting factors and platelets work together to form a clot or thrombus. Although this natural process helps you stop bleeding when you have a cut, it can be harmful when blood clots develop in the arms, legs, or lungs. This process is called the coagulation cascade (Figure 2). One …

Hemopericardium in a Patient Treated with Dabigatran Etexilate

Dabigatran etexilate is a new oral anticoagulant used for the prevention of systemic thromboembolism in patients with atrial fibrillation. Acute bleeding episodes are known to occur with dabigatran etexilate therapy; however, only a few case reports in the literature describe such events. We describe a 70-year-old man treated with dabigatran etexilate for newly diagnosed, nonvalvular atrial fibrillation who developed a large hemopericardium that appeared to be temporally related to dabigatran etexilate administration. One month after starting the drug, an incidental finding of a small pericardial effusion was found on echocardiography. One month later, the patient came to his pulmonologist's office complaining of shortness of breath; a large pericardial effusion was found on a noncontrast computed tomographic scan, and the patient was admitted to the hospital. Laboratory monitoring of his coagulation status was limited due to the lack of assays available to directly monitor the therapeutic effects of dabigatran. The internal laboratory was able to perform a dilute thrombin time (DTT) test as part of a quality improvement project aiming to validate an assay for monitoring patients receiving dabigatran therapy. A DTT was therefore performed in conjunction with routine coagulation assays to evaluate the patient's coagulation status. After pericardiocentesis, the patient recovered without incident and was discharged without anticoagulant therapy. Although the Naranjo adverse reaction probability scale only indicated a possible relationship (score of 1) between the patient's development of hemopericardium and dabigatran etexilate therapy, investigation into the patient's clinical course, comorbidities, and laboratory results led us to conclude that dabigatran etexilate was responsible for the hemopericardium. To our knowledge, this report is the first to describe a case of potentially life-threatening pericardial bleeding that was temporally related to starting dabigatran etexilate therapy. Although we found that the DTT was a viable method of monitoring coagulation status in a patient receiving dabigatran etexilate therapy, the assay lacks approval by the United States Food and Drug Administration, which limits its clinical utility and widespread use at this time. Clinicians should be aware of the potential for life-threatening bleeding with use of this agent and the difficulty associated with monitoring and reversing this therapy in the setting of acute bleeding.

Fibrinogen Šumperk II: Dysfibrinogenemia in an individual with two coding mutations

Fibrinogen—a 340-kDa glycoprotein—plays a crucial role in blood coagulation, platelet aggregation, wound healing, and other physiological processes. A mutation in fibrinogen may lead to congenital dysfibrinogenemia,a rare disease characterized by the functional deficiency of fibrinogen. About 580 cases of abnormal fibrinogens have been reported worldwide; thereof 335 cases in the fibrinogen Aa chain[1]. To our knowledge, only five cases of abnormal fibrinogens with two mutations [2–6] and one case of two different mutations in the same family [7] have been described earlier. A 52-year-old female was examined for bleeding. Routine hemostasis screening resulted in a diagnosis of dysfibrinogenemia. Functional testing revealed prolonged fibrin polymerization, prolonged lysis of the clot, abnormal fibrin morphology,and fibrinopeptides release. Genetic analysis showed two heterozygous nonsense mutations—previously described mutation AaGly13Glu and a novel mutation Aa Ser314Cys. The mutation Aa Gly13-Glu was found in her brother and niece, but there was no evidence in either of the mutation Aa Ser314Cys. While mutation Aa Gly13Glu is responsible for abnormal fibrinopeptide release and prolonged thrombin time, the novel mutation Aa Ser314Cys seems to affect fibrin morphology and fibrinolysis.

Strategies to reduce the use of blood products

Anemia is the most common hematologic problem preoperatively. In itself it compromises the outcome of surgical patients, and additionally results in more frequent allogeneic red blood cell (RBC) transfusions which again independently compromise patient outcome. In elective cardiac surgery as well as in other surgical specialties the use of a patient blood management program will minimize the exposure to blood products, lead to a cost reduction and improve patient's outcome. The aim of this review is to discuss the rationale for patient blood management, explain patient blood management in detail including modern and future transfusion strategies. The risk for allergenic RBC transfusions is increased by preoperative anemia. The adverse outcome in recipients of RBC transfusions has recently been shown to be caused rather than only associated with RBC transfusions. In Jehovah's witnesses undergoing cardiac surgery patient blood management programs have been established effectively, demonstrating that it is possible to correct preoperative anemia and avoid RBC transfusions resulting in better outcomes. Patient blood management strategies are based on an interdisciplinary multimodal approach including early preoperative recognition and treatment of anemic patients, surgical efforts to minimize blood loss, optimal perfusion strategies to reduce hemodilution and continuous assessment of the bleeding and coagulation status of patients as well as a restrictive volume management. This allows specific and goal-directed treatment of patients, preventing anemia in elective patients, optimizing patient's coagulation status early, minimizing exposure to blood products, reducing costs and improving patient's outcome.

Rigid Bronchoscopy: Indications and Techniques

p c t b p p m t v a v s t w o Rigid bronchoscopy is an important procedure for the thoracic surgeon to master. Its utility has been evident since the 1890s when Gustav Killian removed a foreign body from a patient’s right main bronchus and Chevalier Jackson developed his own endoscopes with distal illumination.1,2 Today’s rod-lens telescope was developed by Harold Hopkins in England and is the basic telescope inserted through the rigid bronchoscope. Karl Storz modified this technology with a cold illumination source for his rigid bronchoscope in the 1950s.3 The modern rigid bronchoscope is used for the diagnosis and treatment of benign and malignant pathology of the central airways. Indications for use include, but are not limited to, foreign body retrieval, obtaining hemostasis and removing blood clots in patients with hemoptysis, and relieving airway obstruction from tumors or intubationrelated stenoses. When necessary, rigid bronchoscopy can facilitate the placement of tracheal or bronchial stents. Endoluminal therapies, such as laser treatment, argon plasma coagulation, and debriding instruments, are best used under the protection of a rigid bronchoscope. Rigid bronchoscopy is best used in combination with other modalities, including radiologic studies, such as thin-slice computed tomography scans, flexible bronchoscopy, esophagoscopy, and laryngoscopy. Although they come in various types and sizes, the overall construction of the rigid bronchoscope is typically uniform: a

Portal vein thrombosis following percutaneous transhepatic cholangiography-An unusual presentation of Prothrombin (Factor II) gene mutation

Portal vein thrombosis is an uncommonly reported complication of percutaneous transhepatic cholangiography (PTC). A thorough review of the available literature shows no reported cases. In this case, a 29 year old female presented on two separate occasions with portal vein thrombosis following PTC without drain placement. This unusual complication of image guided percutaneous biliary access is unreported in the literature and prompted evaluation of the patient's coagulation parameters. A thrombophilia screen demonstrated a mutation in the Prothrombin (Factor II) gene. A thorough literature review shows no reported cases of portal vein thrombosis following percutaneous biliary access, is an unusual complication, and should raise suspicion of an underlying pro-coagulant state.

The impact of pre-injury anticoagulation therapy in the older adult patient experiencing a traumatic brain injury: A systematic review.

Review Question/Objective The objective of this systematic review is to synthesize the best available evidence on the impact of pre-injury anticoagulation therapy in the older adult patient who experiences a traumatic brain injury. Inclusion Criteria Types of Participants This systematic review will consider studies which include patients age 65 years or older, regardless of gender or ethnicity, who have experienced a traumatic brain injury. Types of Intervention The intervention of interest is the use of anticoagulants and/or antiplatelet prescription medication prior to the traumatic brain injury. Types of Comparator The intervention of interest will be compared to non-use of prescription anticoagulants and/or antiplatelet medication therapy. Types of Outcome Measures This review will consider studies that include the following outcome measure: death before discharge from the acute care setting.

Left Ventricular Assist Device Induced Coagulation and Platelet Activation and Effect of the Current Anticoagulant Therapy Regimen

Abstract▪2271▪This icon denotes a clinically relevant abstractLeft ventricular assist devices (LVADs) are mechanical pumps used to enhance cardiac function in heart failure patients. Platelet and coagulation activation was quantified to identify if the platelet and clot inhibiting drug regimen is effective in the LVAD patients. Seven patients with implanted LVADs were evaluated monthly for 3 months; 5 healthy adults and 5 patients on warfarin with normal cardiac output served as controls. All subjects signed an informed consent document prior to inclusion in the study. Freshly collected blood was assayed by the following: Plateletworks platelet aggregation (PWs; Helena; Beaumont, TX); PlateletMapping whole blood coagulation and platelet activity (PM; Haemoscope; Niles, IL); and flow cytometry platelet P-selectin upregulation and GPIIb/IIIa receptor activation. All assays used arachidonic acid (AA), ADP, collagen, and thrombin associated receptor activated peptide (TRAP) platelet agonists. In addition, von Willebrand factor (vWF) antigenic levels (Zymutest; Hyphen Biomed, France) were evaluated on frozen stored citrated plasmas. PWs showed a greater inhibition of collagen (31.8 vs 7.1% inh; p=0.008) and AA (30.8 vs 8.2% inh; p=0.002) induced platelet aggregation in patients; ADP induced platelet aggregation was not different between groups (10.8 vs 6.1% inh; p=0.711). PM showed an inhibition trend of AA (36.8 vs 25.1% inh; p=0.491) and ADP (36.2 vs 15.4% inh; p=0.056) mediated coagulation/platelet activation but a greater maximum amplitude of the blood clot in patients compared to normals (69.1 vs 64.9 mm; p=0.012). PM showed no significant inhibition of coagulation (R p=0.719; K p=0.569; angle p=0.430). In patients more than normals, flow cytometry showed an inhibition trend of platelet activation induced by AA (P-selectin: 24.2 vs 31.3% (+), p=0.064; GPIIb/IIIa: 16.8 vs 20.6% (+), p=0.052) and collagen (GPIIb/IIIa: 15.7 vs 29.7% (+), p=0.004); however a similar P-selectin expression to collagen and P-selectin and GPIIb/IIIa receptors to ADP and TRAP agonists was observed. There was no difference in any platelet or coagulation function parameter over the 3 months. The vWF levels, although remaining within the normal range, tended to increase during the 3 month period in the LVAD patients (from 97.9 ± 16.0% to 111.2 ± 18.2% at 1 month and to 113.9 ± 17.4% at 3 months; normals 106.5 ± 11.2%). This study shows that coagulation and platelet activation caused by the LVAD pump and generated shear forces is suppressed only to a limited degree by 81 mg/day aspirin and the anticoagulant effect of 1.8 INR warfarin is not robust. Modifications of the anticoagulant therapy regimen may improve upon the procoagulant effect generated by the LVAD pump. Using such assays as those described could facilitate determination of an optimal dosing strategy, as well as include consideration to avoid any potential increase in risk of bleeding. Disclosures:No relevant conflicts of interest to declare.

Off-Label Use of Recombinant Factor VIIa

Letters6 September 2011Off-Label Use of Recombinant Factor VIIaAnne Phillips, MD, Vice President, Clinical, Medical and Regulatory AffairsAnne Phillips, MD, Vice President, Clinical, Medical and Regulatory AffairsFrom Novo Nordisk, Princeton, NJ 08540.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-155-5-201109060-00020 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail TO THE EDITOR:In the 19 April 2011 issue, Logan and colleagues (1) and Yank and colleagues (2) presented summaries of their assessment of use of recombinant factor VIIa (rFVIIa), sponsored by the Agency for Healthcare Research and Quality (AHRQ) (3). Novo Nordisk is concerned that these articles do not put rFVIIa use into proper context. Most rFVIIa is used in patients with hemophilia with inhibitors in the outpatient setting.In 1972, Ulla Hedner discovered that coagulation factor VII was able to bypass factor VIII/IX–mediated clotting in patients with hemophilia complicated by alloantibodies. Because of the limited availability of plasma ...

Acute spinal subarachnoid haematoma following spinal anaesthesia treated conservatively: case report

Acute spinal subarachnoid haematoma following spinal anaesthesia treated conservatively: case report

Fate of Clots in Patients With Subarachnoid Hemorrhage After Different Surgical Treatment Modality: A Comparison Between Surgical Clipping and Guglielmi Detachable Coil Embolization

Subarachnoid clot is important in the development of delayed vasospasm after subarachnoid hemorrhage (SAH). To compare the clearance of subarachnoid clot and the incidence of symptomatic vasospasm in surgical clipping and embolization with Guglielmi detachable coils for aneurysmal SAH. The subjects were 115 patients with Fisher group 3 aneurysmal SAH on computed tomography scan at admission whose aneurysm was treated by surgical clipping (clip group; n = 86) or Guglielmi detachable coil embolization (coil group; n = 29) within 72 hours of ictus. Software-based volumetric quantification of the subarachnoid clot was performed, and the amount of hemoglobin in drained cerebrospinal fluid was measured. Clearance of the subarachnoid clot on the computed tomography scan was rapid in the clip group until the day after the operation but slow in the coil group (58.9% removed vs 27.8% removed; P = .008). However, postoperative clearance of the clot occurred more rapidly in the coil group. Reduction of the clot until days 3 through 5 did not differ significantly between the 2 groups (72.9% removed vs 75.2% removed). The amount of hemoglobin in the clip group was > 0.8 g/d until day 3 and then gradually decreased (n = 15), but hemoglobin in the coil group remained at > 0.8 g/d until day 5 (n = 17). The incidence of symptomatic vasospasm did not differ between the groups. Subarachnoid clot can be removed directly during surgical clipping, which is not possible with endovascular treatment. However, the percentage reduction of the clot on days 3 through 5 did not differ between the 2 groups.

Anti-Factor V inhibitor in patients with autoimmune diseases: case report and literature review

Acquired anti-Factor V deficiency caused by inhibitor production is a rare coagulation disorder. Although this is a well known entity in the literature, choice of optimal treatment for an individual patient is difficult, given that no standard therapeutic measures are available because of rare incidence and various underlying diseases occurring in the elderly. An 88 year-old man treated for Hashimoto’s disease was found to exhibit prolongation of both prothrombin time and activated partial thromboplastin time. Detailed study of coagulation factors revealed a deficiency of Factor V. Our patient’s coagulation disorder resolved in two weeks with intravenous administration of prednisolone 20 mg/day. Clinical features of autoimmune disease-related Factor V deficiency are discussed, along with eight previously reported cases over the past 20 years.

A case of atypical hemolytic uremic syndrome due to anti-factor H antibody in a patient presenting with a factor XII deficiency identified two novel mutations

A 9-year-old boy with pallor and macrohematuria showed hemolytic anemia, thrombocytopenia and renal failure. There was no history of diarrhea and the stool culture was negative. A diagnosis of atypical hemolytic uremic syndrome (HUS) was confirmed; however, the cause of the prolonged activated partial thromboplastin time (APTT) was unknown. Plasma exchange and hemodialysis were performed because of progressive hemolytic anemia and renal dysfunction. Fresh frozen plasma was administered frequently to correct the prolonged APTT after hemolysis was controlled and C3 levels had recovered. Factor H (FH) and factor I (IF) levels were normal and we did not detect mutations of FH, IF and membrane cofactor protein. Further investigation revealed the presence of anti-FH antibody in the patient's plasma and a deficiency of coagulation factor XII. Analysis of the patient's coagulation system displayed <3% functional activity of factor XII, whereas levels of other coagulation factors were within the normal range. Two novel mutations (W222G and R447S) were identified upon analysis of the factor XII gene in this patient. Moreover, further investigation revealed that compound heterozygous mutations were present in two of the patient's three siblings, while the third sibling only had a mutation at W222G. The patient was treated for atypical HUS; however, no treatment was required for factor XII deficiency as he did not display a hemorrhagic tendency. We report here a rare case of atypical HUS due to anti-FH antibody presenting with a coagulation factor XII deficiency.

Genetic Testing for CYP450 Polymorphisms to Predict Response to Clopidogrel: current evidence and test availabilityApplication: Pharmacogenomics

The anti-platelet agent clopidogrel bisulfate (sold under the trade name Plavix in the United States) is a widely prescribed medication for the prevention of blood clots in patients with acute coronary syndrome, in those who have suffered other cardiovascular disease-related events such as ischemic stroke, and in patients who are undergoing percutaneous coronary intervention. Response to clopidogrel varies substantially due to genetic and acquired factors. Patients who experience recurrent cardiovascular ischemic or thrombotic events while taking clopidogrel are typically described as non-responsive or resistant. The drug's oxidation is mainly dependent on the cytochrome P450 enzyme 2C19 (CYP2C19). Patients with certain genetic variants in CYP2C19 have been found to have lower levels of the active metabolite, less platelet inhibition, and greater risk of major adverse cardiovascular events such as heart attack, stroke, and death. Testing for CYP2C19 polymorphisms may identify patients who will not respond adequately to the standard clopidogrel regimen and who should, consequently, be given an alternate treatment strategy. This article outlines the evidence concerning pharmacogenetic testing for clopidogrel response, including data on clinical validity and clinical utility, and summarizes the currently available tests marketed for this purpose.