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JAMA Pediatrics Apr 2019This cohort study examines the use of closure time following stimulation with collagen and adenosine diphosphate vs the platelet count as a marker of bleeding in...
This cohort study examines the use of closure time following stimulation with collagen and adenosine diphosphate vs the platelet count as a marker of bleeding in premature neonates with thrombocytopenia.
Topics: Bleeding Time; Female; Hemorrhage; Humans; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Longitudinal Studies; Male; Prospective Studies; Thrombocytopenia
PubMed: 30801615
DOI: 10.1001/jamapediatrics.2019.0008 -
Annals of Surgery Feb 1987Baboons that were subjected to systemic hypothermia at 32 C had an arm skin temperature of 27.3 C and bleeding time of 5.8 minutes. With local warming of the arm skin to...
Baboons that were subjected to systemic hypothermia at 32 C had an arm skin temperature of 27.3 C and bleeding time of 5.8 minutes. With local warming of the arm skin to 34 C, the bleeding time was 2.4 minutes. In normothermic baboons with arm skin temperature of 34.6 C, the bleeding time was 3.1 minutes. Local cooling of the arm skin to 27.6 C produced a bleeding time of 6.9 minutes. Increasing the skin temperature of the arm in hypothermic baboons to 38.9 C and in normothermic baboons to 40.1 C reduced bleeding times to 2.1 and 2.3 minutes, respectively. In both hypothermic and normothermic baboons there was a negative and significant correlation between the bleeding time and the arm skin temperature and the thromboxane B2 level in the shed blood obtained at the template bleeding time site. There was a significant positive correlation between the thromboxane B2 level in the shed blood and the arm skin temperature. Both in-vivo and in-vitro studies have shown that the production of thromboxane B2 by platelets is temperature-dependent, and that a cooling of skin temperature produces a reversible platelet dysfunction. Data also suggest that when a hypothermic patient bleeds without surgical cause, skin and wound temperature should be restored to normal before the administration of blood products that are not only expensive but may also transmit disease.
Topics: Animals; Bleeding Time; Blood Platelet Disorders; Female; Hypothermia, Induced; Male; Papio; Skin Temperature; Thromboxane B2
PubMed: 3813688
DOI: 10.1097/00000658-198702000-00012 -
Clinical and Translational Science Aug 2016The effect of the protease-activated receptor-1 (PAR-1) antagonist vorapaxar on human bleeding time is not known. This was a randomized, two-period, open-label trial in... (Randomized Controlled Trial)
Randomized Controlled Trial
The effect of the protease-activated receptor-1 (PAR-1) antagonist vorapaxar on human bleeding time is not known. This was a randomized, two-period, open-label trial in healthy men (n = 31) and women (n = 5). In period 1, subjects received 81 mg aspirin q.d. or a vorapaxar regimen achieving steady-state plasma concentrations equivalent to chronic 2.5 mg q.d. doses, for 7 days. In period 2, each group added 7 days of the therapy alternate to that of period 1 without washout. Bleeding time and platelet aggregation using arachidonic acid, ADP, and TRAP agonists were assessed. Bleeding time geometric mean ratio (90% CI) for vorapaxar/baseline was 1.01 (0.88-1.15), aspirin/baseline was 1.32 (1.15-1.51), vorapaxar + aspirin/vorapaxar was 1.47 (1.26-1.70), and vorapaxar + aspirin/aspirin was 1.12 (0.96-1.30). Unlike aspirin, vorapaxar did not prolong bleeding time compared with baseline. Bleeding time following administration of vorapaxar with aspirin was similar to that following aspirin alone.
Topics: Adenosine Diphosphate; Adult; Arachidonic Acid; Aspirin; Bleeding Time; Blood Coagulation Tests; Drug Therapy, Combination; Female; Healthy Volunteers; Humans; Lactones; Male; Middle Aged; Platelet Aggregation; Pyridines; Receptors, Thrombin; Young Adult
PubMed: 27304196
DOI: 10.1111/cts.12405 -
British Medical Journal (Clinical... Nov 1985Desmopressin acetate 0.3 microgram/kg was given intravenously to nine patients with chronic liver disease and to a further six such patients in a double blind controlled... (Clinical Trial)
Clinical Trial Randomized Controlled Trial
Desmopressin acetate 0.3 microgram/kg was given intravenously to nine patients with chronic liver disease and to a further six such patients in a double blind controlled study versus placebo. Desmopressin acetate significantly shortened the bleeding time compared with basal values in both groups and compared with placebo. There was also a significant decrease in partial thromboplastin time (but not prothrombin time) and significant increases in factor VIII and its components, von Willebrand factor and ristocetin cofactor activity, but not in factors VII, IX, X, XI, or XII. Increased fibrinolysis could be blocked by concomitant administration of tranexamic acid. No important side effects were seen. The multimer pattern of von Willebrand factor was studied for the first time in chronic liver disease. It was normal, but after administration of desmopressin acetate the percentage of multimers of higher molecular weight increased significantly. This may be an important mechanism in the shortening of the bleeding time in cirrhosis, as has been shown in uraemia and other conditions after administration of desmopressin acetate. Desmopressin acetate may be useful in correcting defects in primary haemostasis in chronic liver disease.
Topics: Bleeding Time; Chronic Disease; Clinical Trials as Topic; Deamino Arginine Vasopressin; Double-Blind Method; Humans; Liver Cirrhosis; Random Allocation; von Willebrand Factor
PubMed: 3933677
DOI: 10.1136/bmj.291.6506.1377 -
Arthritis and Rheumatism Nov 2004Systemic lupus erythematosus and antiphospholipid syndrome (APS) often appear concomitantly. Lupus nephritis and antiphospholipid antibody-related ischemic nephropathy...
OBJECTIVE
Systemic lupus erythematosus and antiphospholipid syndrome (APS) often appear concomitantly. Lupus nephritis and antiphospholipid antibody-related ischemic nephropathy cannot be distinguished clinically, although their etiology and treatment differ greatly. Examination of a renal biopsy sample is therefore essential in order to provide the correct treatment. We have observed that patients with lupus anticoagulant (LAC), a serologic marker for APS, often have a prolonged bleeding time, which is a contraindication for performing a percutaneous renal biopsy. We undertook this study to evaluate systematically the bleeding time in 27 consecutive patients.
METHODS
The bleeding time was measured in 27 patients who were persistently positive for LAC and who were not exposed to aspirin or nonsteroidal antiinflammatory drugs. Platelet function and von Willebrand factor (vWF) parameters were subsequently assessed in patients with a prolonged bleeding time.
RESULTS
Twenty-one of 27 patients (78%) had a prolonged bleeding time despite a normal platelet count in the majority of patients (81%). Platelet functioning and vWF parameters in these 21 patients were normal, except for those in 1 patient with a mild storage pool disease.
CONCLUSION
With this study, we introduce yet another paradox in the phenomenon of APS. Although a prolonged bleeding time is generally accepted to be a sign of defective primary hemostasis, LAC is associated with thrombosis. Further studies are needed to elucidate the mechanism behind this disturbance of primary hemostasis.
Topics: Adult; Antiphospholipid Syndrome; Bleeding Time; Female; Humans; Lupus Coagulation Inhibitor; Middle Aged; Platelet Count; Platelet Function Tests; von Willebrand Factor
PubMed: 15529374
DOI: 10.1002/art.20586 -
Clinical and Applied... Apr 2017Aortic valve stenosis (AVS) is the most common valve disease in adults. Severe forms are associated with acquired von Willebrand syndrome (aVWS) with loss of the largest...
Aortic valve stenosis (AVS) is the most common valve disease in adults. Severe forms are associated with acquired von Willebrand syndrome (aVWS) with loss of the largest von Willebrand factor (VWF) multimers. Diagnostic gold standard is the VWF multimer analysis. Valve replacement rapidly restores the VWF structure. Uncertainty exists if this effect is permanent and how functional VWF assays perform compared with multimer analysis. We studied 21 consecutive patients with severe AVS before and 6 to 18 months after valve surgery and compared them with 14 controls without valve disease referred for coronary angiography. The VWF multimers, VWF antigen (VWF:Ag), VWF collagen binding capacity (VWF:CB), VWF:CB/VWF:Ag ratio, in vitro bleeding time (PFA-100), factor VIII coagulation activity (FVIII:C), and VWF ristocetin cofactor activity (VWF:RCo) were determined. In all patients with AVS, the large VWF multimers were strongly reduced (56 ± 13% of normal plasma); all controls had normal multimers. The PFA-100 collagen/ADP closure times (coll/ADP CT) were prolonged in patients with AVS compared with the controls (175 ± 56 seconds vs 86 ± 14 seconds, P < .001). The VWF:CB/VWF:Ag ratio was pathological in 20 of the 21 patients but normal in controls. After surgery, the multimers normalized in all patients and coll/ADP CT shortened (pre 184 ± 65 seconds vs post 102 ± 22 seconds; P < .001). The VWF:CB/VWF:Ag ratio strongly improved ( P < .001) and normalized in 14 of 17 patients. In conclusion, all consecutive patients with severe AVS had an aVWS. The combination of coll/ADP CT and VWF:CB/VWF:Ag ratio detected the aVWS in all patients. More than 6 months after valve replacement, the VWF multimers were still normalized in all patients indicating a permanent cure of the aVWS.
Topics: Aortic Valve Stenosis; Bleeding Time; Blood Coagulation Tests; Case-Control Studies; Heart Valve Prosthesis Implantation; Humans; Protein Multimerization; von Willebrand Diseases; von Willebrand Factor
PubMed: 27481874
DOI: 10.1177/1076029616660759 -
Anesthesiology May 1998Nonsteroidal anti-inflammatory drugs (NSAIDs) may interfere with hemostasis during the perioperative period, and the combination of NSAID and enoxaparin could increase... (Comparative Study)
Comparative Study
BACKGROUND
Nonsteroidal anti-inflammatory drugs (NSAIDs) may interfere with hemostasis during the perioperative period, and the combination of NSAID and enoxaparin could increase this effect. The aim of this prospective, blinded experimental study was to assess these effects using a model of arterial thrombosis and bleeding in the rabbit.
METHODS
After anesthesia was induced and monitors placed, the common carotid arteries were exposed, and 60% stenosis of the right common carotid artery was produced. Twenty minutes later, a compression injury of the artery was produced that triggered a series of cyclic episodes of thrombosis and clot lysis. This was manifested as cyclic flow reductions (CFR; measured with an electromagnetic flow meter). After the first flow reduction was noted, the rabbits were immediately and randomly assigned to one of four groups (n = 10 each) that received intravenous infusions: control, ketorolac (2 mg/kg), enoxaparin (0.5 mg/kg), and ketorolac plus enoxaparin (2 mg/kg and 0.5 mg/kg, respectively). The number of CFRs that occurred in the subsequent 20-min period was used as a measure of treatment effect. The contralateral common carotid artery was exposed, and both stenosis and injury were produced. The ability of the administered drug to prevent thrombosis was assessed as the number of CFRs that occurred during the first 20-min period after vessel injury. In addition, both before and after group assignment and drug injection, bleeding times were noted and a platelet aggregation test was performed. Laparotomy was followed by a spleen section, and the extent of the wound and the amount of splenic bleeding were measured.
RESULTS
The treatment effect was indicated by the median number of CFRs, which was 5.5 in the control group, 1 in the ketorolac group, 2 in the enoxaparin group, and 0 in the ketorolac + enoxaparin group. The prevention effect was indicated by the median number of CFRs, which was 4 in the control group, 0 in the ketorolac group, 2 in the enoxaparin group, and 0.5 in the ketorolac + enoxaparin group. Bleeding time was significantly lengthened in the enoxaparin and in the ketorolac + enoxaparin groups. Splenic and wound bleeding was greater in the ketorolac group. Platelet aggregation was completely inhibited in the ketorolac and the ketorolac + enoxaparin groups.
CONCLUSIONS
Ketorolac had an important antithrombotic activity. The association of enoxaparin with ketorolac seemed to lengthen the bleeding time observed with ketorolac.
Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Anticoagulants; Bleeding Time; Blood Coagulation; Carotid Artery Thrombosis; Drug Interactions; Enoxaparin; Ketorolac; Male; Platelet Aggregation; Platelet Aggregation Inhibitors; Rabbits; Tolmetin
PubMed: 9605692
DOI: 10.1097/00000542-199805000-00023 -
Ulusal Travma Ve Acil Cerrahi Dergisi =... Nov 2020Algan Hemostatic Agent (AHA) is a multi-herbal extract containing a standardized amount of Achillea millefolium, Juglans regia, Lycopodium clavatum, Rubus caesius or...
BACKGROUND
Algan Hemostatic Agent (AHA) is a multi-herbal extract containing a standardized amount of Achillea millefolium, Juglans regia, Lycopodium clavatum, Rubus caesius or Rubis fruciosus, Viscum album, and Vitis vinifera, each of which is effective in hemostasis. In this study, we aimed to investigate the effects of AHA on bleeding time in a rat tail hemorrhage model.
METHODS
Forty-eight Sprague Dawley rats (5-7 weeks old, 180-210 g) were randomly and equally allocated to six groups as follows: heparin plus saline (heparinized control), heparin plus AHA-soaked sponge, heparin plus liquid form of AHA, saline (non-heparinized control), AHA-soaked sponge and liquid form of AHA. Heparin (640 IU/kg) was administered intraperitoneally three times a day for three days in heparinized groups. For the bleeding model, the tail of rats was transected. According to the study group, either saline- or AHA-soaked sponge or liquid form of AHA was applied over the hemorrhage area. In AHA- or saline-soaked sponge groups, once the bleeding time had started, it was checked every 10 seconds. If the bleeding did not stop after 40 seconds, it was accepted as a failure. In liquid AHA group, the duration of bleeding was measured using a chronometer and defined as the time (seconds) from wounding until the bleeding stopped.
RESULTS
Bleeding time in the heparinized and non-heparinized control groups was over 40 seconds. After applying the sponge form of AHA on the wound area, bleeding time was significantly shortened to less than 20 seconds in both heparinized and non-heparinized rats (p<0.001 for both). The liquid form of AHA stopped bleeding in 5.0±1.2 seconds and 8.0±1.3 seconds in heparinized and non-heparinized groups, respectively.
CONCLUSION
AHA is a highly effective topical hemostatic agent in a rat tail hemorrhage model, thus may provide for a unique clinically effective option for control of bleeding during surgical operations or other emergencies.
Topics: Animals; Bleeding Time; Disease Models, Animal; Hemorrhage; Hemostasis; Hemostatics; Plant Preparations; Rats; Rats, Sprague-Dawley; Tail
PubMed: 33107963
DOI: 10.14744/tjtes.2020.50384 -
Acta Neurochirurgica Jul 2020Traumatic brain injury (TBI) and alcohol use disorder (AUD) can occur concomitantly and be associated with coagulopathy that influences TBI outcome. The use of bleeding...
BACKGROUND-AIM
Traumatic brain injury (TBI) and alcohol use disorder (AUD) can occur concomitantly and be associated with coagulopathy that influences TBI outcome. The use of bleeding time tests in TBI management is controversial. We hypothesized that in TBI patients with AUD, a prolonged bleeding time is associated with more severe injury and poor outcome.
MATERIAL AND METHODS
Moderate and severe TBI patients with evidence of AUD were examined with bleeding time according to IVY bleeding time on admission during neurointensive care. Baseline clinical and radiological characteristics were recorded. A standardized IVY bleeding time test was determined by staff trained in the procedure. Bleeding time test results were divided into normal (≤ 600 s), prolonged (> 600 s), and markedly prolonged (≥ 900 s). Normal platelet count (PLT) was defined as > 150,000/μL. This cohort was compared with another group of TBI patients without evidence of AUD.
RESULTS
Fifty-two patients with TBI and AUD were identified, and 121 TBI patients without any history of AUD were used as controls. PLT was low in 44.2% and bleeding time was prolonged in 69.2% of patients. Bleeding time values negatively correlated with PLT (p < 0.05). TBI patients with markedly prolonged values (≥ 900 s) had significantly increased hematoma size, and more frequently required intracranial pressure measurement and mechanical ventilation compared with those with bleeding times < 900 s (p < 0.05). Most patients (88%) with low platelet count had prolonged bleeding time. No difference in 6-month outcome between the bleeding time groups was observed (p > 0.05). Subjects with TBI and no evidence for AUD had lower bleeding time values and higher platelet count compared with those with TBI and history of AUD (p < 0.05).
CONCLUSIONS
Although differences in the bleeding time values between TBI cohorts exist and prolonged values may be seen even in patients with normal platelet count, the bleeding test is a marker of primary hemostasis and platelet function with low specificity. However, it may provide an additional assessment in the interpretation of the overall status of TBI patients with AUD. Therefore, the bleeding time test should only be used in combination with the patient's bleeding history and careful assessment of other hematologic parameters.
Topics: Adult; Alcoholism; Bleeding Time; Blood Coagulation; Brain Injuries, Traumatic; Female; Humans; Male; Middle Aged
PubMed: 32424564
DOI: 10.1007/s00701-020-04373-y -
Hematology/oncology and Stem Cell... Sep 2018The precise mechanisms of the increased incidence of hemostatic abnormalities in congenital heart disease (CHD) have not been determined. The aim of the study was to... (Clinical Trial)
Clinical Trial
BACKGROUND
The precise mechanisms of the increased incidence of hemostatic abnormalities in congenital heart disease (CHD) have not been determined. The aim of the study was to evaluate some indicators of activation of platelets and vascular endothelial cells in patients with CHD, evaluation of bleeding liability of these patients, and correlation with the clinical presentation of these patients.
METHODS
This work was carried out on 20 patients with cyanotic congenital heart diseases (CCHD), 20 patients with acyanotic congenital heart diseases (ACHD), and 20 healthy children who served as the control group, aged between 1 and 10years. All were subjected to full clinical examination, complete blood count, oxygen saturation, echocardiography, bleeding and coagulation times, PT, PTT, FDPs, plasma soluble P-selectin, E-selectin, and platelet factor 4 (PF4).
RESULTS
There was significant prolongation of PT and PTT, and there was a significant lowering of platelet counts. These results were obtained in CCHD and ACHD, but were more significant in CCHD patients. There was a significant elevation in PF4 (55.0±25.5ng/mL), P-selectin (128.9±42.44ng/dL), and E-selectin (9461.5±1701.24pg/mL) levels in children with CCHD as compared to those with ACHD (PF4, 21±7.94ng/mL; P-selectin, 80.1±13.2ng/mL; E-selectin, 7969.6±2127.5pg/mL), and significant increase in both groups when compared to the control group (PF4, 8.1±4.7ng/mL; P-selectin, 27.83±9.73ng/mL; E-selectin, 6750.00±3204.00pg/mL). There was a significant negative correlation between oxygen saturation, plasma P-selectin (r=-0.865), E-selectin (r=-0.401), and PF4 (r=-0.792) in patients with CCHD.
CONCLUSION
Patients with CHD-both cyanotic and acyanotic-have variable degrees of increased liability for both thrombosis and hemorrhage that represents some sort of adaptation to preserve hemostasis and to protect these patients against the clinical presentation of both thrombosis and bleeding. This is to say that CHD patients have their own point of balance between thrombogenicity and bleeding liability. Wide-scale studies are needed to detect the normal levels of different thrombohemorrhagic parameters of these patients.
Topics: Bleeding Time; Blood Coagulation Tests; Child; Child, Preschool; E-Selectin; Female; Heart Defects, Congenital; Hemorrhage; Humans; Infant; Male; P-Selectin; Platelet Count; Thrombosis
PubMed: 28867175
DOI: 10.1016/j.hemonc.2017.07.001