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PubMed1982

Effects of intravenous indoprofen on bleeding time and other haemostatic parameters.

The influence of i.v. administration of indoprofen on template bleeding time and other haemostatic parameters was investigated in ten elderly subjects with osteoarthritis. The drug was given first as a single dose (400 mg bolus) and then, after an appropriate interval, as a short-term treatment (200 mg bolus t.i.d. for 7 days). Platelet count, prothrombin time and partial thromboplastin time were never affected, whereas a significant, though moderate, lengthening of bleeding time and a parallel reduction of platelet aggregation were observed in both trials. In the acute one these changes were seen at the first hour following administration and waned in all patients within 96 hours. In the subacute test the bleeding time was steadily prolonged throughout the week of treatment, being slightly still above the baseline value 7 days later, at which time no residual effects were noticeable in platelet aggregation.

Aged↗
PubMed2001

Effect of activated prothrombin complex concentrate or recombinant factor VIIa on the bleeding time and thrombus formation during anticoagulation with a direct thrombin inhibitor.

UNLABELLED: Melagatran is the active form of the oral, direct thrombin inhibitor H 376/95. In several animal models of thrombosis, the antithrombotic properties of melagatran have been demonstrated, without any increase in experimental bleeding. However, as with all anticoagulants, in emergency situations, reversal of the anticoagulation may be necessary. In this study, increasing doses of activated prothrombin complex concentrate (APCC, Feiba) or recombinant factor VIIa (r-F VIIa, NovoSeven) were superimposed on high doses of melagatran, or saline, in anaesthetised rats. The haemostatic effect was evaluated in two bleeding time models and a potential prothrombotic effect was evaluated in an arterial thrombosis model. Compared with melagatran alone (0.5 micromol/kg/h), Feiba in doses of > or =25 U/kg significantly shortened the prolonged bleeding time and reduced blood loss. In addition, Feiba > or =50 U/kg when added to melagatran (2 micromol/kg/h), significantly reduced bleeding time. No potentiation of thrombus formation was observed when Feiba was added to melagatran, compared with controls. NovoSeven at high doses (2-10 mg/kg) produced a nonsignificant trend in reduction of blood loss and with the highest dose (10 mg/kg) producing only a mild nonsignificant reduction in bleeding time. The prolonged prothrombin time (PT) and the ecarin clotting time (ECT) were more effectively shortened by Feiba than by NovoSeven. In contrast, whole blood clotting time (WBCT) was more effectively shortened by NovoSeven than by Feiba. Activated partial thromboplastin time (APTT) was shortened by NovoSeven but was prolonged by Feiba. Thrombin-antithrombin (TAT) complex formation was increased in a dose-dependent fashion more effectively by Feiba than by NovoSeven. CONCLUSION: Feiba (APCC) reversed prolonged bleeding time and blood loss in rats treated with high doses of melagatran and compared with the control group thrombus formation was not potentiated. NovoSeven (r-F VIIa) at high doses had less pronounced effects on blood loss and bleeding times compared with Feiba.

Animals↗
PubMed1989

ITP in pregnancy: use of the bleeding time as an indicator for treatment.

ITP is a relatively common disorder seen in pregnancy. Current recommendations for management of patient with ITP recommend maintaining the platelet count above 50 x 10(9)/L and the bleeding time less than 20 min. It has been well documented that the bleeding time in ITP is disproportionately shortened in many patients relative to the platelet count. We present a prospective study of 24 ITP patients in whom the bleeding time was used as an indicator for therapeutic intervention in pregnancy. Indications for therapy with prednisone and/or intravenous gammaglobulin were the following: significant clinical hemorrhage due to thrombocytopenia; bleeding time of greater than 20 min at the baseline platelet count; for normalization of hemostasis prior to delivery or surgical procedure. Caesarean section was performed only in cases in which there were obstetrical indications for this mode of delivery or when the fetal platelet count (obtained by fetal scalp vein sample) was less than 50 x 10(9)/L. Of 24 patients with ITP, eight had significant thrombocytopenia (platelet count less than 50 x 10(9)/L) throughout pregnancy. Only two patients required prolonged prednisone therapy. Both suffered side effects of chronic prednisone administration. Four patients were treated with prednisone for a short course (10-14 days) at term to improve hemostasis for delivery. One patient was treated with intravenous gammaglobulin at term in an effort to prevent severe neonatal thrombocytopenia. Seven patients required caesarean section; the remaining 17 patients underwent vaginal delivery. Only one minor bleeding complication was seen - a small wound hematoma post caesarean section. In summary, using the bleeding time as an indicator for therapeutic intervention, treatment of ITP in pregnancy can be minimized. Thus, therapy related toxicity can be avoided.

Autoimmune Diseases↗
PubMed1998

The preoperative bleeding time test lacks clinical benefit: College of American Pathologists' and American Society of Clinical Pathologists' position article.

The major conclusions of this position article are as follows: (1) In the absence of a history of a bleeding disorder, the bleeding time is not a useful predictor of the risk of hemorrhage associated with surgical procedures. (2) A normal bleeding time does not exclude the possibility of excessive hemorrhage associated with invasive procedures. (3) The bleeding time cannot be used to reliably identify patients who may have recently ingested aspirin or nonsteroidal anti-inflammatory agents or those who have a platelet defect attributable to these drugs. The best preoperative screen to predict bleeding continues to be a carefully conducted clinical history that includes family and previous dental, obstetric, surgical, traumatic injury, transfusion, and drug histories. A history suggesting a possible bleeding disorder may require further evaluation; such an evaluation may include performance of the bleeding time test, as well as a determination of the platelet count, the prothrombin time, and the activated partial thromboplastin time. In the absence of a history of excessive bleeding, the bleeding time fails as a screening test and is, therefore, not indicated as a routine preoperative test.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2003

The effect of IM ketorolac tromethamine on bleeding time: a prospective, interventional, controlled study.

Opiates, although effective analgesics, have significant adverse side effects. Ketorolac, the only parental nonsteroidal antiinflammatory drug available for use in the United States does not cause significant respiratory depression or hypotension, but it is a reversible inhibitor of platelet aggregation with a theoretical increased bleeding risk, which limits its use. The objective of this study was to determine the effect of a single intramuscular dose of 60 mg ketorolac on 4-hour bleeding times in healthy volunteers. This was a prospective, paired, unblinded, before-and-after interventional study performed in a suburban university-based EM residency training program. Subjects were 20 healthy volunteer EM residents. Standard Ivy bleeding times were measured before and 4 hours after intramuscular administration of 60 mg ketorolac. Before-and-after bleeding times were compared using a paired t-test. The study had 90% power to detect an effect size of 0.5. The subjects' mean age was 31.6 and 7 (35%) were females. Bleeding time was increased from a mean baseline time of 3 minutes 34 seconds (+/- 1 min 20 sec) to a mean 4-hour postinjection time of 5 minutes 20 seconds (+/- 3 min 8 sec). The mean prolongation of bleeding time was 1 minute 46 seconds (50% increase with 95% confidence interval, 25%-75%). There were no adverse events. A standard intramuscular dose of 60 mg ketorolac resulted in prolongation of the bleeding time in healthy volunteers. The clinical significance of this prolongation in patients is unclear.

Adult↗
PubMed1988

Clinical application of a new in vitro bleeding time device on surgical patients.

A new in vitro bleeding time (BT) device was applied to various surgical patients. After setting the optimal assay condition, the normal in vitro bleeding time (T2) and volume (V2) were obtained from healthy volunteers, being 114.7 secs +/- 25.8 (SD) and 272.2 microliter +/- 69.1 (SD), respectively. When the T2 was below 210 secs, the platelet count was inversely proportional to the T2 and V2 of the in vitro BT with p less than 0.01. The value of the in vitro BT was not affected by heparin. Agents, which modify platelet functions, such as PGI2, DN9693 (an inhibitor of phosphodiesterase) and aspirin, prolonged the in vitro BT (T2, V2) dose-dependently. Administration of aspirin (660 mg) to volunteers prolonged the T2 from 108 to over 300 secs and the V2 from 253 to over 600 microliter but ticlopidine (500 mg/day for 3 days) had no effect. In 8 patients with liver cirrhosis who underwent hepatectomy, one patient with a prolonged T2 (260 secs) and a normal skin BT bled postoperatively, however, 3 patients with a prolonged skin BT (greater than 15 min) and a normal T2 had no hemorrhagic complications. From these observations it was concluded that in vitro BT is a convenient and useful tool to examine primary hemostasis or platelet function.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1988

[Measurement of bleeding time and study of thrombocyte aggregation. Standardization of methods, normal values and results in patients with suspected hemorrhagic diathesis].

Bleeding time measurement and investigation of platelet aggregation in platelet rich plasma (PRP) are routine procedures for the diagnosis of defects in primary hemostasis. These tests are subject to methodological difficulties and should be well standardized in each individual laboratory. - In the present study, bleeding time was measured using the Simplate II device in 40 normal subjects. Furthermore, platelet aggregation in PRP induced by ADP, collagen, arachidonate, and ristocetin was examined. 26 patients referred for investigation of a suspected mild bleeding disorder, who had a normal plasmatic coagulation profile, a normal von Willebrand factor activity, and a normal platelet count, were similarly studied. - Based on the reference values established in the 40 normal subjects, platelet aggregation was found to be pathologic in 7 patients and normal in 12. In 7 patients platelet aggregation was considered to be borderline-pathologic as defined by the range of platelet aggregability found in the 10% of our normal subjects showing the weakest aggregation responses. Bleeding time was prolonged in only 3 patients whereas it was normal in the remaining 23. There was strong evidence of a hemostatic defect as assessed by systematic patient history in 6 out of 7 patients with pathologic platelet aggregation, but in only 3 out of 19 showing normal or borderline-pathologic aggregation. - Pathologic platelet aggregation, therefore, represents not only an abnormal laboratory finding but is likely to be associated with a hemorrhagic diathesis. Platelet aggregation studies do not permit etiologic diagnosis of the thrombocytopathy except for the well-defined membrane glycoprotein deficiencies. The bleeding time appeared to be of low sensitivity for the diagnosis of mild platelet dysfunction.

Adolescent↗
PubMed1991

The bleeding time effects of a single dose of aspirin in subjects receiving omega-3 fatty acid dietary supplementation.

Dietary supplementation with omega-3 fatty acids reduces platelet aggregation in subjects who usually eat a diet low in these fatty acids. Aspirin also has an antiplatelet effect. The clinical effects of the concomitant administration of these agents were examined in this double-blind controlled crossover trial. Twelve healthy adults were randomized to supplement their diet for 21 days with 8 g of omega-3 fatty acids or identical-looking olive oil capsules. At the end of each treatment period, bleeding times were obtained before and after the administration of one 325-mg aspirin tablet. Overall, percent change in bleeding time after omega-3 fatty acid supplementation was significantly prolonged compared with olive oil supplementation before aspirin administration but not after. Bleeding times were influenced significantly by the order of randomization in the two treatment groups. Changes in post-aspirin bleeding time varied in subjects after they received olive oil. Post-aspirin bleeding times after omega-3 fatty acid supplementation were prolonged compared with baseline values but not significantly prolonged when compared with those after olive oil administration. The authors concluded that the concomitant administration of a single dose of aspirin does not prolong bleeding time in subjects who eat a diet enriched by omega-3 fatty acids versus a diet enriched by olive oil.

Aspirin↗
PubMed1997

YM-60828, a novel factor Xa inhibitor: separation of its antithrombotic effects from its prolongation of bleeding time.

The antithrombotic effects of intravenous infusions of YM-60828 ([N-[4-[(1-acetimidoyl-4-piperidyl)oxy]phenyl]-N-[(7-amidino-2-nap hthyl)methyl]sulfamoyl]acetic acid dihydrochloride), a novel factor Xa inhibitor, argatroban, heparin and dalteparin in an arterio-venous shunt model were studied in comparison with their effects on template bleeding time. In an arterio-venous shunt model, all agents exerted antithrombotic effects in a dose-dependent manner. ID50 values of YM-60828, argatroban, heparin and dalteparin were 0.0087 mg/kg/h. 0.027 mg/kg/h, 22 IU/kg/h and 11 IU/kg/h, respectively. In bleeding time studies, all agents prolonged bleeding time in a dose-dependent manner. Doses (ED2) of YM-60828, argatroban, heparin and dalteparin, which caused 2-fold prolongation of bleeding time in the saline group, were 3.0 mg/kg/h, 0.25 mg/kg/h, 18 IU/kg/h and 26 IU/kg/h. respectively. The risk-benefit ratio (ED2/ID50) of YM-60828 was much greater than that of the other agents. These data suggest that the antithrombotic effect of YM-60828 is separate from its prolongation of bleeding time and that YM-60828 is much safer than conventional anticoagulant agents.

Animals↗
PubMed1994

Bleeding times related to serum triglyceride levels in healthy young adults.

A diet rich in fish tends to increase the bleeding time both in patients and healthy controls. Another effect of such a diet is a reduction in serum triglyceride levels in the individuals. It is not known whether these two effects are interrelated. In order to rule out effects of selenium in the fish diet, half of a control group consumed bread enriched with selenium while the other half had a normal diet. This combined control group (n = 21) was compared with healthy volunteers (n = 11) eating 250 g of fish daily for six weeks. Blood tests were performed at the start of the study, after three weeks and at the end. Changes in bleeding time were then related to changes in hemostatic variables and serum lipids. An inverse correlation (r = -0.41, p = 0.001) was present in the controls between serum triglyceride levels and bleeding times, but neither of the two variables changed in the course of the study. A negative correlation was observed in the fish eating group, and a change in the variables mentioned occurred in an orderly manner in the course of the study: a prolongation of the bleeding time from the start of the study to the end was only seen in individuals with low triglyceride levels, i.e. less than 1 mmol/L. Selenium in the diet, on the other hand, did not affect any of the observed variables.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

The effect of low dose aspirin on bleeding times.

This double-blind, controlled study assessed the effect of low-dose aspirin on bleeding times. Thirty patients, in the last trimester of their first pregnancy, who were also taking part in a trial to evaluate the effect of low-dose aspirin on the development and progress of pregnancy-induced hypertension, had their bleeding times measured using the Simplate 11 Bleeding Device. Our study showed there was no significant difference between the bleeding times of the two groups and all measurements fell within the normal range.

Aspirin↗
PubMed1990

1-Desamino-8-D-arginine vasopressin (DDAVP) infusion in type IIB von Willebrand's disease: shortening of bleeding time and induction of a variable pseudothrombocytopenia.

We have investigated the effects of 1-desamino-8-D-arginine vasopressin (DDAVP) infusion on platelet count and bleeding time in 4 patients with type IIB von Willebrand's disease (vWd). Three of four patients showed a normalization of the bleeding time within 1 h after the infusion, while bleeding time was not modified in the fourth. In accordance with the literature, thrombocytopenia was observed after DDAVP infusion, but this thrombocytopenia was due to the anticoagulants used for blood collection. In two patients (F.I., G.F.) no thrombocytopenia was observed when platelets were counted by fingerstick method but there was a 20% platelet decrease in blood samples collected in sodium citrate and a 50% decrease in samples collected in EDTA. Dramatic falls in platelet counts (70-95%) were observed in the additional two patients (C.A., D.Z.) after DDAVP infusion, when both sodium citrate or EDTA were used as anticoagulants. In the latter two patients there was also a 50% decrease in platelet count when the fingerstick method was used. The decrease in the patient's platelet count in EDTA samples after DDAVP infusion could be prevented, in part, by the previous additions of an anti GPIb monoclonal antibody and an anti GPIIb-IIIa monoclonal antibody. Thus, the thrombocytopenia observed in the four IIB vWd patients studied after DDAVP infusion seems to be, at least partially, a pseudothrombocytopenia depending on the calcium concentration in the blood samples and the availability of GPIb and GPIIb-IIIa receptors. These findings and the normalization of the bleeding time observed in three of the four patients has led us to reconsider the possible use of DDAVP in the treatment of our IIB vwd patients.

Anticoagulants↗
PubMed1981

Prolonged bleeding time with adequate platelet count in hospital patients.

100 patients with a modified Ivy bleeding time longer than 10 min in the presence of more than 80 x 10(9)/l blood platelets were studied retrospectively. 72 patients had repeated bleeding times between 10 and 20 min or one or more measurements exceeding 20 min, and were considered to have an unquestionable platelet dysfunction. 39 (54%) of these 72 patients were receiving large doses of antibiotics. Nearly one half of the patients on antibiotics had a bleeding tendency, but most of these patients had additional features that may have interfered with platelet function, or a coagulation defect. In the remaining 33 patients, the prolonged bleeding time was associated with von Willebrand's disease, liver disease, leukaemia/myeloproliferative disease, paraproteinaemia or aspirin ingestion. High doses of penicillin seem to be the most common cause of qualitative platelet disorders in general hospital practice.

Adolescent↗
PubMed1985

Effect of temocillin and moxalactam on platelet responsiveness and bleeding time in normal volunteers.

The effects of temocillin and moxalactam on platelet responsiveness and bleeding time were examined in healthy male volunteers. In the first study, moxalactam (4 g intravenously every 12 h) was given to six subjects; template bleeding times were at least doubled in five subjects 12 to 14 h after 7 doses (P = 0.008) and in all six subjects 12 to 14 h after 13 doses (P = 0.004). ADP-induced primary aggregation was approximately halved after 7 (P = 0.026) and 13 doses (P = 0.008), and there was a markedly increased tendency toward disaggregation. Collagen-induced aggregation was also halved, but the effect only reached statistical significance after 13 doses (P = 0.008). There was essentially no effect on primary aggregation in response to the thromboxane receptor agonist U46619 or to platelet activating factor. Temocillin (4 g intravenously every 12 h) was given to eight subjects, three of whom had participated in the moxalactam study 8 weeks earlier. Temocillin had no significant effect on template bleeding time 12 to 14 h after 7 or 13 doses. However, in four subjects, the endpoint may have been less abrupt. There was no significant effect on ADP-induced primary aggregation or responsiveness to collagen. Even after 13 doses of temocillin, secondary aggregation in response to normal concentrations of ADP was demonstrable in the platelet-rich plasma of all eight subjects. Neither antibiotic had any effect on prothrombin times. Thus, with methodology that readily detected the effects of moxalactam on hemostasis, we were unable to demonstrate any unequivocal deleterious effects of temocillin at its maximum recommended dose. Temocillin may therefore be particularly useful for the treatment of many gram-negative infections in patients at increased risk of clinical bleeding.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed2006

Ex vivo evaluation of anti-GPVI antibody in cynomolgus monkeys: dissociation between anti-platelet aggregatory effect and bleeding time.

Recent progress in the understanding of thrombus formation has suggested an important role of glycoprotein (GP)VI. In contrast to its pivotal role in collagen-induced platelet activation, it has been suggested that its blockade does not induce massive bleeding tendency. To demonstrate the dissociation between inhibitory effect on platelet aggregation and bleeding by GPVI blockade, we examined the effects of Fab fragment of OM2, an anti-human GPVI monoclonal antibody on ex vivo collagen-induced platelet aggregation and skin bleeding time after intravenous injection in cynomolgus monkeys. In a dose-escalation study, OM2 potently (> 80%) inhibited collagen-induced platelet aggregation at the cumulative dose of 0.2 mg/kg with a slight prolongation of bleeding time (1.3 times baseline value). Furthermore, at 18.8 mg/kg, the highest dose tested, prolongation of bleeding time was still mild (1.9 times). In contrast, abciximab, Fab fragment of anti-GPIIb/IIIa antibody prolonged bleeding time by 5.0 times at 0.35 mg/kg, the lowest effective dose on platelet aggregation. In a pharmacodynamic study, a bolus injection of OM2 at 0.4 mg/kg produced potent inhibition of collagen-induced aggregation up to six hours after injection, showing longer half-life than that of abciximab. The injection of OM2 Fab did not induce thrombocytopenia and GPVI depletion in monkeys. These results suggest that blockade of GPVI by antibody can exert a potent inhibitory effect on collagen-induced platelet aggregation with a milder prolongation of bleeding time than blockade of GPIIb/IIIa. This study indicates that OM2 has the potential to be developed as a new class of therapeutic tool.

Animals↗
PubMed2005

Antiplatelet and antithrombotic activity of cilostazol is potentiated by dipyridamole in rabbits and dissociated from bleeding time prolongation.

PURPOSE: To determine the antiplatelet effect of cilostazol (Pletal) and its interaction with dipyridamole in in vitro and in vivo rabbit models, and to see if it can be dissociated from bleeding time prolongation. METHODS: In vitro collagen-induced platelet aggregation was measured by an impedance-based aggregometer. The in vivo antithrombotic effect was evaluated in a rabbit carotid artery cyclic flow reduction (CFR) model, in which repetitive thrombosis was induced by mechanical injuries of the artery and stenosis. Template bleeding time was determined in rabbit ear arterioles and hindlimb nail cuticles. RESULTS: In vitro platelet aggregation was slightly inhibited by 4 microM cilostazol (22 +/- 6%), and modestly by 13 microM (57 +/- 3% of aggregation). While dipyridamole itself up to 13 microM had no significant inhibition, it potentiated the effect from cilostazol: in the presence of 4 microM dipyridamole, 4 microM cilostazol inhibited aggregation by 47 +/- 6%. Dipyridamole also potentiated the CFR reducing effect of cilostazol: combination of dipyridamole (no effect by itself) and cilostazol at 1 microM decreased CFRs to levels achieved by 3-4 microM cilostazol alone. Bleeding times were similar in controls and animals treated with cilostazol, or with cilostazol and dipyridamole. In contrast, aspirin (4 mg/kg), while reducing CFRs, significantly increased bleeding time. CONCLUSION: These results suggest that dipyridamole potentiates the antiplatelet effect of cilostazol without prolongation of the bleeding time, implying a potential novel combination antithrombotic therapy.

Animals↗
PubMed1994

Recombinant human erythropoietin shortens the bleeding time and corrects the abnormal platelet aggregation in hemodialysis patients.

Uremia may be associated with abnormal hemostasis characterized by a prolonged bleeding time and abnormal in-vitro platelet aggregation. The mechanisms underlying these derangements are not fully elucidated. The present study examined the effect of correction of anemia by recombinant human erythropoietin (r-HuEPO) on these abnormalities in eight dialysis patients. Prior to r-HuEPO therapy the patients had low hematocrits (Hct) (20% +/- 0.7), abnormal bleeding times (23 +/- 1.2 minutes), and marked impairment in platelet aggregation induced by adenosine diphosphate (ADP), epinephrine (Epi), thrombin (Th) and collagen. After correction of the anemia to a Hct of 32% +/- 0.9 over 5 +/- 0.9 months, there were a) significant shortening of the bleeding time (from 23 +/- 1.2 to 10.6 +/- 2.4 minutes, p < 0.01), b) an inverse correlation between the Hct and the bleeding time (r = -0.89, p < 0.001) and c) significant improvement, or normalization of platelet aggregation in response to both concentrations of epinephrine [Epi2 (5.4 x 10(-6) M), 45% +/- 10.5 vs 73.5% +/- 7.3, p < 0.01, and Epi1 (5.4 x 10(-5) M), 49% +/- 10.6 vs 64% +/- 6.6, p < 0.05)], both concentrations of ADP [ADPC'(2 x 10(-6) M), 31% +/- 5.9 vs 60% +/- 9.3, p < 0.05, and ADPB (2 x 10-5), 69.5% +/- 7.6 vs 99% +/- 4.8, p < 0.01], and both concentrations of thrombin [ThC (0.22 u/ml) 28.6% +/- 8.9 vs 80.4% +/- 8.3, p < 0.01, and TH50/50 (0.44 u/ml), 57.8% +/- 6.7 vs 83.3% +/- 9.2, p < 0.01)].(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Diphosphate↗
PubMed1990

Studies in patients with bleeding disorders show that platelet-vessel interaction is important for thromboxane formation in bleeding time wounds.

The production of thomboxane B2, the primary metabolite of thromboxane A2, and 6-keto prostaglandin F1 alpha, the primary metabolite of prostacyclin, were measured in response to a standardized vascular injury, the bleeding time, in patients with von Willebrand's disease and in patients with platelet function defects. Compared to controls, thromboxane B2 levels in bleeding time blood were significantly lower in subjects with von Willebrand's disease. In patients with platelet function defects associated with a deficient response to thromboxane A2, thromboxane B2 production in bleeding time blood was similar to controls. In subjects with other platelet function defects, thromboxane production was significantly lower than normal. 6-keto PGF1 alpha production in bleeding time blood was not significantly different in patients compared to controls. The results suggest that bleeding time thromboxane production is influenced by the extent of platelet-vessel interaction.

6-Ketoprostaglandin F1 alpha↗