Anticoagulant therapy after prosthetic valve replacement -optimal PT-INR in Japanese patients-.
(41/626)
Values of the international normalized ratio of prothrombin time (PT-INR) were analyzed at the time when anticoagulant-related complications developed in patients undergoing prosthetic valve replacement so as to evaluate the optimal therapeutic range in PT-INR value in Japanese patients. A total of 102 patients with a prosthetic heart valve who have been followed up at our department during the past 25 years were enrolled in this study. PT-INRs were determined regularly in these patients for the period between October 1996 and March 1999. Although no thromboembolic complications occurred during the period of this study, hemorrhagic complications developed in 26 (25.5%) patients. Three (2.9%) patients suffered from life threatening bleeding, such as cerebral bleeding and gastrointestinal bleeding and were defined as the major hemorrhagic group. Another 23 (22.5%) patients had minor bleeding complications such as nasal, gingival or subcutaneous bleeding and were defined as the minor hemorrhagic group. Mean PT-INR values were 3.8 2.0 and 3.2 1.0 at the onset of the complications in major and minor hemorrhagic groups, respectively, and there was no significant difference between the two groups. However, mean PT-INR values in the minor bleeding group differed significantly from that in a patient group with no hemorrhagic complications (N=76). Among the cases with bleeding complications, only 19% of the patients belonged to the range below 2.5 of PT-INR value and 54% of the patients were included in the range from 2.5 to 3.5 (p<0.05). In conclusion, the optimal therapeutic range between 2.5 and 3.5 in PT-INR recommended by the American Heart Association for patients with a prosthetic heart value in Western countries may be too high in Japanese patients. PT-INR below 2.5 is considered to be safe to prevent hemorrhagic complications. (+info)
Aspirin and postoperative bleeding after coronary artery bypass grafting.
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OBJECTIVE: To evaluate the relationship between aspirin ingestion and postoperative bleeding complications, and to test the hypothesis that there is a subset of patients who are aspirin hyperresponders with a proclivity toward platelet dysfunction. SUMMARY BACKGROUND DATA: Despite numerous retrospective and prospective analyses, it is still controversial as to whether aspirin ingestion before coronary artery bypass grafting (CABG) is associated with significant postoperative bleeding. METHODS: Between January 1995 and December 1999, the records of 2,606 consecutive patients undergoing CABG were reviewed to identify patients with a history of aspirin ingestion up until the time of surgery. Aspirin ingestion was correlated with postoperative blood transfusion using multivariate analysis. In a subset of preoperative aspirin users (n = 40), bleeding times were measured before and after aspirin use. Flow cytometry was performed in another cohort of patients with known heart disease (n = 30) to determine the effect of aspirin on platelet surface receptors. RESULTS: During the 5-year study period, 63% of the CABG patients were identified as aspirin users. Among these, 23.1% required blood transfusions compared with 19% for the nonusers. Non-red blood cell transfusions were more common in aspirin users, as was reexploration for bleeding. Stratification of these results according to the frequency of aspirin use showed that aspirin is an independent multivariate predictor of postoperative blood transfusion only in high-risk patients. In the prospective studies, aspirin treatment resulted in a significant increase in the template bleeding time, an increase in platelet PAR-1 thrombin receptor activity, and a decrease in the binding of platelets to monocytes. CONCLUSIONS: The findings support the hypothesis that aspirin is associated with a greater likelihood of postoperative bleeding. A platelet function testing algorithm that combines preoperative risk factor assessment, template bleeding times, and flow cytometry may allow the identification of aspirin hyperresponders who are at increased risk for bleeding. (+info)
Increased risk for postoperative hemorrhage after intracranial surgery in patients with decreased factor XIII activity: implications of a prospective study.
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BACKGROUND AND PURPOSE: The functional integrity of the hemostatic system is a prerequisite for the safe performance of neurosurgical procedures. To monitor the individual coagulation capacity of each patient, standard tests are effective to detect deficiencies involving the generation of fibrin. However, fibrin clot strength depends primarily on coagulation factor XIII, which cross-links fibrin monomers and enhances clot resistance against fibrinolysis. Therefore, factor XIII is functionally involved in both the hemostatic and fibrinolytic systems. The objective of this prospective study was to determine the incidence and clinical relevance of perioperative decreased factor XIII with respect to standard coagulation parameters and the occurrence of postoperative hematoma. METHODS: In 876 patients, 910 neurosurgical procedures were performed. Prothrombin time (PT), partial thromboplastin time (PTT), platelet count, fibrinogen, and factor XIII were tested in each patient preoperatively and postoperatively. RESULTS: Postoperative intracranial hematoma (defined as requiring surgical evacuation) occurred after 39 (4.3%) of 910 surgical procedures. Patients with postoperative hematoma had significantly lower factor XIII and fibrinogen levels preoperatively and postoperatively than patients without hematoma. In patients with postoperative hematoma, PT and platelets differed significantly only postoperatively, whereas PTT was different neither preoperatively nor postoperatively. Of the 39 patients with a postoperative hematoma, 13 (33.3%) had a postoperative factor XIII <60% compared with 61 (7%) of 867 patients without hematoma (P<0.01, Fisher's exact test). The relative risk of developing a postoperative hematoma is therefore increased 6.4-fold in patients with postoperative factor XIII <60%. The risk is increased 12-fold in patients who additionally have postoperative decreased fibrinogen levels (<1.5 g/L) and 9-fold in patients with platelet count <150x10(9)/L and factor XIII <60%. CONCLUSIONS: This is the first prospective study that demonstrates the association of decreased perioperative factor XIII with an increased risk of postoperative hematoma in neurosurgical patients. The risk is further increased in those patients with low factor XIII and additional abnormalities of fibrinogen, PT, platelets, and PTT. Factor XIII testing and specific replacement, as accepted for other clotting factors, may reduce the risk of postoperative hematoma. (+info)
Coronary artery bypass surgery with heparin-coated perfusion circuits and low-dose heparinization.
(44/626)
OBJECTIVE: To evaluate the safety and efficacy of heparin-coated perfusion circuits with low-dose heparinization and centrifugal pumping compared with the standard method during coronary artery bypass grafting. DESIGN: Prospective, randomized, single-blind clinical trial. SETTING: A primary care institution. PATIENTS: Ninety patients who underwent first-time elective coronary artery bypass grafting were eligible for the study. After giving informed consent, they were randomly assigned to 1 of 3 groups (30/group). INTERVENTIONS: Perfusion on regular uncoated bypass equipment with a roller pump and full-dose heparinization (300 IU/kg bolus, activated clotting time [ACT] > 400 s) (group 1), on a heparin-coated oxygenator with a centrifugal pump and full-dose heparinization (group 2) and on fully heparin-coated bypass equipment with a centrifugal pump and low-dose heparinization (100 IU/kg bolus, ACT of 180-400 s) (group 3). Standard coronary artery bypass grafting was performed. OUTCOME MEASURES: Postoperative bleeding, transfusion requirements and clinical outcomes. RESULTS: There were no complications related to the study protocol. Study groups were similar in terms of postoperative bleeding, transfusion requirements and clinical outcomes. CONCLUSIONS: Heparin-coated cardiopulmonary bypass with low-dose heparinization and centrifugal pumping is a safe practice but showed no advantages over the use of regular uncoated bypass circuits for coronary bypass surgery. (+info)
Video-assisted thoracic surgery for mediastinal extramedullary haematopoiesis.
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Extramedullary haematopoiesis is a rare cause of an intrathoracic mass. We report a case of posterior mediastinal extramedullary haematopoietic mass in a 50-year-old man who presented with non-specific symptoms and a paravertebral mass on chest X-ray. Diagnosis was achieved by using video-assisted thoracic surgery. (+info)
The effect of clopidogrel in combination with aspirin when given before coronary artery bypass grafting.
(46/626)
OBJECTIVES: This study was designed to evaluate the effect of preoperative clopidogrel on coronary artery bypass graft surgery (CABG) outcomes. BACKGROUND: Clopidogrel in combination with aspirin, given before percutaneous coronary intervention, has become the standard for stent thrombosis prevention. Some premedicated patients, however, are found to have surgical disease on angiography, and irreversible platelet inhibition becomes a concern for upcoming CABG. METHODS: We prospectively studied 224 consecutive patients undergoing nonemergent first-time CABG, and compared those with preoperative clopidogrel exposure within seven days (n = 59) to those without exposure (n = 165). RESULTS: The groups were comparable in age, gender, body surface area, preoperative hematocrit, preoperative prothrombin time and prior myocardial infarction. The clopidogrel group had higher 24-h mean chest tube output (1,224 ml vs. 840 ml, p = 0.001), and more transfusions of red blood cells (2.51 U vs. 1.74 U, p = 0.036), platelets (0.86 U vs. 0.24 U, p = 0.001) and fresh frozen plasma (0.68 U vs. 0.24 U, p = 0.015). Moreover, reoperation for bleeding was 10-fold higher in the clopidogrel group (6.8% vs. 0.6%, p = 0.018). The clopidogrel group also had less extubation within 8 h (54.2% vs. 75.8%, p = 0.002) and a trend towards less hospital discharge within five days (33.9% vs. 46.7%, p = 0.094). CONCLUSIONS: Clopidogrel in combination with aspirin before CABG is associated with higher postoperative bleeding and morbidity. These findings raise concern regarding the routine administration of clopidogrel before anticipated coronary stent implantation. (+info)
Intraoperative low-volume acute normovolemic hemodilution in adult open-heart surgery.
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BACKGROUND: Recently, various studies have questioned the efficacy of intraoperative acute normovolemic hemodilution (ANH) in reducing bleeding and the need for allogeneic transfusions in cardiac surgery. The aim of the present study was to reevaluate the effects of a low-volume ANH in elective, adult open-heart surgery. METHODS: Two hundred four consecutive adult patients undergoing cardiac surgery were prospectively randomized in a nonblinded manner into two groups: ANH group (103 patients), where 5-8 ml/kg of blood was withdrawn before systemic heparinization and replaced with colloid solutions, and a control group, where no hemodilution was performed (101 patients). Procedures included single and multiple valve surgery, aortic root surgery, coronary surgery combined with valve surgery, or partial left ventriculectomy. The purpose of the study was to evaluate the efficacy of ANH in reducing the need for allogeneic blood components. Routine hematochemical evaluations, perioperative blood loss, major complications, and outcomes were also recorded. RESULTS: No differences were found between the groups regarding demographics, baseline hematochemical data, and operative characteristics. There was no difference in the amount of transfusions of packed red cells, fresh frozen plasma, platelet concentrates, total number of patients transfused (control group, 36% vs. ANH group, 34.3%; P = 0.88), and amount of postoperative bleeding (control group, 412 ml [313-552 ml] vs. ANH group, 374 ml [255-704 ml]) (median [25th-75th percentiles]); P = 0.94. Further, perioperative complications, postoperative hematochemical data, and outcomes were not different. CONCLUSIONS: In patients undergoing elective open-heart surgery, low-volume ANH showed lack of efficacy in reducing the need for allogeneic transfusions and postoperative bleeding. (+info)
Preoperative use of enoxaparin compared with unfractionated heparin increases the incidence of re-exploration for postoperative bleeding after open-heart surgery in patients who present with an acute coronary syndrome: clinical investigation and reports.
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BACKGROUND: Enoxaparin has become an attractive therapy for use during acute coronary syndrome (ACS) because of its potential superior efficacy over unfractionated heparin (UFH), its longer activity, and its subcutaneous route of administration. However, because a significant number of patients presenting with ACS may be sent directly to open heart surgery while still on anticoagulation, it is important to understand any potential bleeding risks that may be associated with the use of enoxaparin under these circumstances. METHODS: From 1998 to 2001, 1159 consecutive patients presenting with an acute coronary syndrome who received either UFH (n=1008) or enoxaparin (n=151) before proceeding to open heart surgery for urgent therapy during the same hospitalization were included in this study. Incidence of perioperative bleeding as evidenced by the units of blood products (packed red blood cells or platelets) transfused or the need for surgical re-exploration for postoperative bleeding was recorded. RESULTS: Average age was 65+/-11 and 67+/-11 years for patients receiving UFH and enoxaparin, respectively (P=0.005). Seventy-five percent of those receiving UFH and 64% of those receiving enoxaparin (P<0.005) were males. After discharge, the incidence of rehospitalization for hemorrhage requiring return to surgery for re-exploration was 7.9% in the enoxaparin group and 3.7% in the UFH group (adjusted hazard ratio=2.6, P=0.03). The use of blood products did not differ between groups (UFH=2.7+/-6.5 U and enoxaparin=2.3+/-4.5 U; P=NS). CONCLUSION: The preoperative use of enoxaparin compared with UFH in patients presenting with an ACS who undergo open-heart surgery during the same hospitalization is associated with a significantly increased incidence of re-exploration for postoperative bleeding. Further study is needed to understand the mechanism of this phenomenon and to develop appropriate guidelines to address this potentially important issue. (+info)