Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0162871 (abdominal aortic aneurysm)
 8,664 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of hetastarch and human albumin solutions on perioperative bleeding and coagulation parameters during abdominal aortic aneurysm repair were compared. In two randomized groups of 20 patients, albumin 5% (group 1) or hetastarch 6% (group 2) 1 g/kg was given during surgery. The remaining perioperative fluids consisted of lactated ringers and packed red blood cells. Perioperative coagulation measurements included partial thromboplastin time, prothrombin time, activated clotting time, platelet count, and bleeding time. Estimated blood loss and the total amount of crystalloid and blood infused were also measured. The surgeon, blind to the colloid used, subjectively rated bleeding on a scale of 1 to 10. There was no significant difference between groups for any measured parameter at any time. Measurements of coagulation function were within normal limits for both groups. Hetastarch does not cause clotting disorders in patients undergoing abdominal aortic aneurysm repair, at least if the quantities used in this study are not exceeded.
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PMID:Comparison of hetastarch to albumin for perioperative bleeding in patients undergoing abdominal aortic aneurysm surgery. A prospective, randomized study. 169 Sep 74

Factor X (FX) "Vorarlberg" is a congenital FX deficiency characterized clinically by a mild bleeding tendency. Homozygous individuals have a FX activity of less than 10% in the extrinsic system and 25% in the intrinsic system. FX antigen is 20%. Using molecular techniques, two point mutations were detected in the coding sequence of the FX Vorarlberg gene: a G----A at base pair 160 in exon II resulting in a change of Gla14 (GAA) to Lys (AAA); a G----A at base pair 424 in exon V resulting in a change from Glu102 (GAG) to Lys (AAG). The mutations abolished a TaqI restriction site in exon II and an MnlI site in exon V. To determine whether these mutations are present on one or on both alleles, restriction analyses of amplified exon II and exon V fragments were performed. Analysis of the pedigree showed that the genotype for the mutation on exon II (homozygous versus heterozygous) correlates with the severity of the phenotypic coagulation defect. We therefore conclude that the mutation in exon II is responsible for the functional defect in FX Vorarlberg. We have also purified the mutant FX protein from patient plasma. Purified FX Vorarlberg is indistinguishable from normal FX on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Its activity is 15% of normal FX upon activation with factor VIIa/tissue factor, 75% upon activation with factor IXa/factor VIIIa, and 100% upon activation with RVV. Activation at varying Ca2+ concentrations shows that the affinity of FX Vorarlberg for Ca2+ is decreased. Factor Xa Vorarlberg is able to convert prothrombin at a normal rate but also shows decreased affinity for Ca2+ in this interaction. Upon addition of Ca2+, FX Vorarlberg does not undergo the same conformational change as normal FX. Our data show that FX Vorarlberg has a decreased affinity for Ca2+ which impedes a normal conformational change. This leads to a decreased rate of activation by factor VIIa/tissue factor and by factor IXa. The decrease is much more marked for the extrinsic than for the intrinsic pathway.
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PMID:Molecular defect (Gla+14----Lys) and its functional consequences in a hereditary factor X deficiency (factor X "Vorarlberg"). 197 67

A study was conducted to estimate the functional reserve of the liver of patients with severe hepatitis by computed tomography (CT), in particular employing the integrated CT number of the whole liver (ICTN). ICTN was calculated by integrating the product of "area" times "mean CT number" of the liver in each CT slice for the entire height of the liver. The following results were obtained: 1) In patients with fulminant hepatitis (FH) as well as those with subacute hepatitis (SAH), ICTN was found to be significantly lower as compared to that of patients with acute hepatitis (AH) or non-hepatic diseases. In addition, in FH and SAH patients, ICTN showed a larger degree of decrease when compared with such conventional parameters as either estimated liver volume or mean hepatic CT number. Thus, ICTN seems to more sensitively reflect the changes in functional reserve of the liver. 2) ICTN showed significant positive correlations with prothrombin time and plasma BCAA/AAA ratio, and a significant negative correlation with plasma methionine level. 3) Time course of changes in ICTN correlated well with the clinical features of severe hepatitis. In particular, patients with initial ICTN values above 20 l.HU/m2 of body surface area showed significantly higher survival rate than those with initial ICTN below 20. In conclusion, ICTN well indicates the functional reserve of the liver, and is further suggested to be valuable as a parameter to predict the prognosis of patients with severe hepatitis.
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PMID:Determination of the integrated CT number of the whole liver in patients with severe hepatitis: as an indicator of the functional reserve of the liver. 274 45

The surgical operations including 5 cholecystectomies, gastrectomy, and graft implantation for abdominal aortic aneurysm were performed on 7 patients 2 to 98 months after valve replacement. Sodium warfarin was routinely used in an amount to reduce the prothrombin activity in a range of 20-30% normal by thrombotest. In all cases, anticoagulants were reduced in doses gradually in the period of 4 to 15 days proceeding to the operation. Heparin therapy was instituted for the prevention of thromboembolism, when prothrombin activity recovered to 50% normal by thrombotest, in 5 of 7 cases. Heparin therapy was interrupted just prior to operations and it was reinstituted soon after operations in 6 cases. Heparin therapy was maintained by continuous intravenous infusion to produce ACT of 130 to 150 seconds. Heparin therapy was stopped when prothrombin activity reached a therapeutic level with sodium warfarin. There were two episodes of hemorrhage required blood transfusion, observed in patients receiving heparin therapy, but there was no thromboembolism. We believe that our method which minimizes the nonanticoagulated time appears safe and effective in patients with prosthetic heart valves who require noncardiac operations.
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PMID:[Surgery of the patients on anticoagulants following prosthetic valve replacement]. 362 99

A prospective comparison of thrombelastography to standard coagulation tests was undertaken in ten patients undergoing routine, uncomplicated abdominal aortic aneurysm surgery in order to explore potential clinical utility and establish normal patterns of change. Thrombelastograph k values increased (7.1 vs 5.4 min baseline, P < or = .01), and alpha angle (43 vs 52 degrees baseline, P < or = .001) and ma (39 vs 52 mm baseline, P < or = .01) values decreased following graft placement, while r values remained unaffected (6.4 vs 7.5 min baseline, P > .05). Weak correlations were observed between alpha angle and fibrinogen, prothrombin time, and partial thromboplastin time (aPTT), as well as between k and aPTT (0.70 < r < 0.79 for all). Systemic fibrinolysis was suggested by thrombelastography in 25% of samples, although euglobulin lysis times were abnormal in only 5% (chi 2 = 4.80, P < or = .05). Fibrin degradation product detection increased through the fifth postoperative day in all patients. Variations in thrombelastographic parameters and their correlation to standard coagulation tests in patients undergoing uncomplicated abdominal aortic aneurysm repair were documented. In such a setting, no clear advantages to thrombelastography were defined. Further observations will be necessary to establish the role for thrombelastography in the management of patients experiencing clinically significant perioperative coagulation disorders.
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PMID:Coagulation status during aortic aneurysm surgery: comparison of thrombelastography with standard tests. 812 14

Significant hematologic changes are known to occur following intraoperative autotransfusion of shed blood, but the clinical importance of cell washing prior to reinfusion has not been substantiated. To evaluate these changes and their relationship to the use of blood bank products and postoperative morbidity, 26 patients undergoing elective abdominal aortic aneurysm repair were prospectively randomized to reinfusion with washed shed blood or to the use of a collection system in which filtered, but unwashed, whole blood was reinfused intraoperatively. Each patient was evaluated with respect to standard metabolic and hematologic laboratory parameters preoperatively, immediately postoperatively, and 12 to 18 hours postoperatively. Patient demographic data were similar for both groups. Perioperative survival was 100% for both groups. Total blood loss and blood volume autotransfused were significantly greater in the unwashed cell group compared with the washed cell group (p = 0.00014 and p = 0.00011, respectively). Hemoglobin, fibrinogen, prothrombin time, and partial thromboplastin time levels were not significantly different between the two groups at any time perioperatively; fibrin split product and d-dimer levels were significantly higher in the unwashed cell group postoperatively (p = 0.016 and p < 0.001, respectively). Serum free hemoglobin levels were significantly higher in the immediate postoperative period in the unwashed cell group compared with the washed cell group (p = 0.0013); by 12 to 18 hours postoperatively, this difference was not significant. Haptoglobin levels were significantly lower in the unwashed cell group at both postoperative times (123 +/- 86 mg/dL versus 41 +/- 50 mg/dL, p = 0.0086; 102 +/- 66 mg/dL versus 24 +/- 36 mg/dL, p = 0.0001); however, there was no perioperative renal failure in either group. Furthermore, homologous blood product use was not significantly different between the two groups, with an average of 1.5 +/- 2.5 units of packed red blood cells given to patients in the unwashed cell group versus 0.8 +/- 1.7 units in the washed cell group (p = 0.419). Overall complications were higher and critical care and total hospital stays were longer in the unwashed cell group but did not result from autotransfusion of unwashed blood. We conclude that the intraoperative reinfusion of unwashed shed blood is safe and effective, causing transient hematologic abnormalities that normalize in the early postoperative period, and is not associated with increased mortality, or hematologic, cardiopulmonary, or renal complications.
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PMID:Cell washing versus immediate reinfusion of intraoperatively shed blood during abdominal aortic aneurysm repair. 835 24

In a prospective study of 50 consecutive patients undergoing operation for ruptured abdominal aortic aneurysm, a coagulation screen was performed on admission to hospital. Twenty patients with either a platelet count < 100 x 10(9)/l or a prothrombin time > 1.5 times the control value had a mortality rate of 65 per cent (95 per cent confidence interval 45-85 per cent); a further 23 patients with normal screen results had a mortality rate of 9 per cent (95 per cent confidence interval 0-20 per cent) (P < 0.001). Seven patients, of whom three died, did not have an admission coagulation screen performed. Patient age in the study group did not have independent statistical predictive power. This study indicates that coagulopathy at the time of admission predicts poor outcome in patients with ruptured aortic aneurysm. Current management strategies are inadequate for the treatment of these patients, who can be rapidly identified on admission by means of platelet and prothrombin counts.
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PMID:Preoperative coagulopathy in ruptured abdominal aortic aneurysm predicts poor outcome. 840 93

BACKGROUND: Previous work has demonstrated that ruptured abdominal aortic aneurysm (AAA) is associated with systemic thrombin generation and inhibition of systemic fibrinolysis. The procoagulant and hypofibrinolytic state associated with ruptured AAA predisposes to microvascular and macrovascular thrombosis and subsequent myocardial injury. The aim of this study was to determine the relationship between haemostatic derangement and biochemical evidence of myocardial injury in patients operated on for ruptured AAA. METHODS: Ten patients undergoing repair of ruptured AAA were studied. Tissue plasminogen activator (tPA) activity, plasminogen activator inhibitor (PAI) activity, prothrombin fragment (PF) 1 + 2, D-dimer and fibrinogen levels were measured before operation, and immediately before and 5 min after aortic clamp release. Plasma levels of cardiac troponin (cTn) I were measured before operation, and 6 and 24 h after aortic clamp release. RESULTS: There was no relationship between tPA activity, PF 1 + 2, D-dimer or fibrinogen and cTn-I levels at any sampling point. There was, however, a significant positive correlation (Spearman rank test) between PAI activity immediately before (median 38.6 (range 13.0-39.4) units ml-1) and 5 min after (37.2 (10.6-39.4) units ml-1) aortic clamp release, and cTn-I at 6 h (median 3.17 (range less than 0.5 to 71.1) ng ml-1) and 24 h (5.55 (range less than 0.5 to 110) ng ml-1) after aortic clamp release. CONCLUSION: These data strongly support the hypothesis that the inhibition of systemic fibrinolysis which occurs in response to ischaemia and reperfusion during ruptured AAA repair contributes to the development of subsequent myocardial injury.
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PMID:Vascular surgical society of great britain and ireland: inhibition of systemic fibrinolysis is associated with myocardial injury in patients operated on for ruptured abdominal aortic aneurysm 1036 22

Perioperative hemorrhage is one of the principal causes of death in patients with ruptured abdominal aortic aneurysm (AAA). This study examines perioperative coagulation and fibrinolysis in patients undergoing ruptured AAA repair complicated by coagulopathy. Eight patients (8 men of median age 74, range 69-87, years) who developed clinical and laboratory evidence of coagulopathy during attempted repair of ruptured infrarenal AAA were prospectively studied. Platelet count, fibrinogen, clotting times, prothrombin fragment (PF) 1+2, and tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) activities were measured preoperatively, immediately before, and 5 min and 24 hr after aortic declamping. Six patients died, three intraoperatively, one within 24 hr, and two in the late postoperative period. All patients had thrombocytopenia and prolonged clotting times intraoperatively with evidence of increased thrombin generation (as demonstrated by elevated PF 1+2). Five patients had increased systemic fibrinolysis (as demonstrated by elevated t-PA activity) preoperatively and/or before aortic declamping and all of these patients died. Three patients had perioperative inhibition of systemic fibrinolysis (as demonstrated by elevated PAI activity) and two survived. These data demonstrate that coagulopathy in ruptured AAA repair may be associated with a hyperfibrinolytic state. Further research is required to determine if (a) a causal relationship exists between hyperfibrinolysis and coagulopathy and (b) whether antifibrinolytic agents can improve outcome if targeted at this group of patients.
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PMID:Coagulopathy and hyperfibrinolysis in ruptured abdominal aortic aneurysm repair. 1553 37

Elective surgery of abdominal aortic aneurysm (AAA) sometimes leads to excessive bleeding and disseminated intravascular coagulation (DIC), even in patients with normal preoperative coagulation parameters. Coagulation screen, performed routinely before surgery is of limited value in the assessment of compensated activation of the haemostatic system. In this study, we used a number of additional tests (D-dimer, prothrombin fragment 1+2, antithrombin, and activation of fibrinolysis in the platelet poor plasma) for the diagnosis of compensated activation of the haemostatic system in AAA-patients. D-dimer and marker of thrombin generation (prothrombin fragment 1+2) positively correlated with each other (r = 0.768, P < 0.001). Out of 71 AAA patients, 15 patients had normal global coagulation times, but those with a D- dimer concentration above 3000 ng/ml were selected for preoperative low molecular weight heparin (LMWH) treatment. Administration of LMWH diminished coagulation abnormalities (D-dimer and prothrombin fragment 1+2 decreased significantly) and resulted in the increase of platelet number and fibrinogen concentration, indicating their previous consumption. Despite differences in aneurysm diameters between the groups of 15 LMWH treated patients (mean 70.9 +/- 16 mm) and the reference group of 20 untreated AAA patients (mean 52.3 +/- 8.0 mm), intraoperative parameters (operation time, blood loss and transfusion demands) were similar.
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PMID:Compensated activation of coagulation in patients with abdominal aortic aneurysm: effects of heparin treatment prior to elective surgery. 1554 26


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