Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ACENOCOUMAROL”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 343 records · Page 19Linked to original sources
PubMed1985

Antithrombotic effect of ticlopidine in a platelet-independent model of venous thrombosis.

The antithrombotic activity of ticlopidine demonstrated in a variety of experimental models of thrombosis has been explained by its antiaggregating properties. This study describes the antithrombotic effect of ticlopidine in a platelet independent model of venous thrombosis. In the rat, ligature of the inferior vena cava induces thrombosis. Antiaggregating drugs (acetylsalicylic acid, dipyridamole, sulfinpyrazone) are inactive while anticoagulants (heparin, acenocoumarol) are highly antithrombotic. Ticlopidine reduces thrombus weight significantly and dose-dependently (ED 50 = 150 mg/kg/day X 3 days). Thrombocytopenia induced by injection of anti-platelet anti-serum was found not to modify thrombus formation. Yet, even in these conditions, ticlopidine remains active. Acetylsalicylic acid treatment does not prevent the antithrombotic effect of ticlopidine, indicating that its action is independent of PGI2 synthesis. These results demonstrate that ticlopidine acts as an antithrombotic agent in a venous thrombosis model in which platelets play a minor role.

Animals↗
PubMed1984

Pregnancy after heart valve replacement.

Thirty-two women, aged 21 to 44 years, who had undergone single (25) or multiple (7) heart valve replacement conceived 46 times and gave rise to 33 live-born infants. There were 12 abortions and one stillborn; a premature baby died 24 hr post-partum. Twenty-eight patients had mechanical prostheses and 4 had porcine xenografts, 29 patients being anticoagulated with acenocoumarol during the pregnancy. Cardiac status remained clinically satisfactory under medical treatment in all but one patient who developed heart failure. Fetal complications included cerebral hemorrhage in 1 premature infant, low birth weight in 3 newborns and 1 case of nasal hypoplasia. The incidence of abortion has decreased significantly during the latter part of our experience. It was significantly greater in patients with mitral prostheses. This review suggests that inadequate cardiac function, excessive anticoagulation and a history of primary infertility may increase the risk of abortion. Better control of anticoagulant therapy (accepting an elevation of the therapeutic limit) and improved prevention of pregnancy in high-risk patients are considered responsible for the improved results seen in recent years.

Abortion, Spontaneous↗
PubMed1991

Thermospray and particle beam liquid chromatographic-mass spectrometric analysis of coumarin anticoagulants.

Positive ion mass spectra were obtained from several coumarin oral anticoagulants (phenprocoumon, warfarin, acenocoumarol and dicoumarol) and derivatives by liquid chromatography-thermospray mass spectrometry (LC-TSP-MS) and liquid chromatography-electron impact mass spectrometry (LC-EI-MS) to assess the use of LC-MS methods for the determination of these compounds in biological materials. LC-TSP mass spectra showed a single [M + 1]+ ion with no fragmentation; LC-EI mass spectra showed fragment ions which were similar in mass and relative intensities to those obtained by conventional EI-MS. These data should serve as a basis for the development of LC-MS methods for the qualitative and quantitative analysis of coumarin anticoagulants in biological samples. LC-TSP-MS was applied to the determination of phenprocoumon in a plasma extract from an anticoagulated patient.

Anticoagulants↗
PubMed1996

Failure of adjusted doses of subcutaneous heparin to prevent thromboembolic phenomena in pregnant patients with mechanical cardiac valve prostheses.

OBJECTIVES: This report describes our experience with the use of an anticoagulant regimen of adjusted doses of subcutaneous heparin during pregnancy in women with cardiac valve prostheses. BACKGROUND: Gravid patients with prosthetic heart valves require long-term anticoagulant therapy. To avoid the increased incidence of fetal morbidity and mortality associated with the use of coumarin agents in such patients during pregnancy, anticoagulation with subcutaneous heparin has been suggested. Controversy exists concerning the appropriate treatment of these patients. METHODS: Forty pregnancies in 37 women with prosthetic heart valves were prospectively followed up. Subcutaneous heparin was administered from the 6th until the end of the 12th week and in the last 2 weeks of gestation. Heparin was given every 8 h in the first 36 cases and every 6 h in the last 4 cases, and the dose adjusted to maintain the activated partial thromboplastin time at 1.5 to 2.5 times the control level. Acenocoumarol was used at other times. RESULTS: The incidence rate of spontaneous abortions was 37.5%; there was one neonatal death (2.5%) due to cerebral hemorrhage. No signs of coumarin-induced embryopathy were found in any of the 16 live-born infants studied by the geneticist. One mother died of gastrointestinal bleeding while receiving oral anticoagulant agents. There were two cases of fatal massive thrombosis of a mitral tilting-disk prosthesis during heparin therapy. The study was interrupted after the last of these two cases. CONCLUSIONS: The regimen of adjusted doses of subcutaneous heparin used in this study is not effective to prevent thrombosis of mechanical valve prostheses during pregnancy. The use of heparin from the 6th to the 12th week of gestation does not decrease the high incidence of fetal wastage associated with anticoagulant therapy. Coumarin agents provide adequate protection against thromboembolism during pregnancy in patients with mechanical valve prostheses.

Abnormalities, Drug-Induced↗
PubMed2005

10-year experience with the ATS mechanical valve in the mitral position.

BACKGROUND: The ATS Medical Open Pivot mechanical heart valve was introduced in 1992. Previous reports have focused on the low rate of thromboembolic complications in the aortic position. The purpose of this retrospective study is to analyze the rate of midterm thromboembolic events and other valve-related complications when the ATS Open Pivot valve is implanted in the mitral position. METHODS: Between June 1992 and June 2002, 177 patients (63 male and 114 female; mean age 57.5 years) underwent mitral replacement with an ATS Open Pivot mechanical heart valve. Preoperatively, 17 patients (10%) were in New York Heart Association functional class II, 117 patients (66%) in class III, and 43 patients (24%) in class IV. Seventy-four patients (42%) were in chronic atrial fibrillation. Seventy-four mitral valve replacements (42%) were associated with other cardiac procedures. Etiologies included degenerative disease (56%), rheumatic disease (38%), and endocarditis (6%). On the second postoperative day, 100 mg acetylsalicylic acid and oral acenocoumarol (Sintrom) was introduced to obtain a target INR of 2.0 to 3.0. All patients were followed up by one cardiologist and underwent annual transthoracic echocardiographic examination. RESULTS: Percent follow-up was 90.4%. Data represent 724 total patient-years. Mean follow-up was 48 +/- 34 months (range, 1 to 119). Operative morbidity was 15%. Overall hospital mortality was 2.8% (5 patients). At hospital discharge, the mean INR for all the patients was 2.38 +/- 0.68 (range, 1.32 to 6.44). Five early neurologic complications occurred: 3 transient cerebrovascular accidents and 2 strokes. Three late transient cerebrovascular ischemic accidents occurred at 3, 4, and 6 years, respectively. No other complications such as paravalvular leak, valve dysfunction, thrombosis, or valve explant occurred. Postoperative echocardiographic data revealed low mean pressure gradient as related to the valvular size. CONCLUSIONS: The ATS Medical Open Pivot mitral valve demonstrates low rates of bleeding, thromboembolic, and other valve-related complications.

Adult↗
PubMed2004

Effects of cytochrome P450 2C9 polymorphisms on phenprocoumon anticoagulation status.

OBJECTIVE: Our objective was to assess whether there is an association between the presence of allelic variants of the gene for cytochrome P450 (CYP) 2C9 and anticoagulation problems during the initial phase of phenprocoumon treatment. METHODS: A prospective follow-up study was performed at 2 anticoagulation clinics in The Netherlands. Included subjects started phenprocoumon during the study period, had their first check of the international normalized ratio (INR) on the third or fourth day of therapy, and had an indication for the low therapeutic range (INR, 2.0-3.5). CYP2C9 genotypes ( CYP2C9*1 , CYP2C9*2 , and CYP2C9*3 ) were assessed, and data on indication, INR checks, comedication, and comorbidity were collected. RESULTS: After genotyping, 284 subjects were available for analysis. Of these, 186 (65.5%) were homozygous carriers of the CYP2C9 wild-type allele ( CYP2C9*1/*1 ), 61 (21.5%) were carriers of the CYP2C9*2 allele, and 37 (13.0%) were carriers of the CYP2C9*3 allele. Compared with homozygous CYP2C9*1/*1 subjects, carriers of CYP2C9*2 or *3 had an increased risk of severe overanticoagulation (INR >6.0). The hazard ratio for CYP2C9*2 versus CYP2C9*1/*1 was 3.09 (95% confidence interval [CI], 1.56 to 6.13; P=.001), and the hazard ratio for CYP2C9*3 versus CYP2C9*1/*1 was 2.40 (95% CI, 1.03 to 5.57; P=.042). Carriers of CYP2C9*2 also had a lower chance to achieve stability in the follow-up period. The hazard ratio for CYP2C9*2 versus CYP2C9*1/*1 was 0.61 (95% CI, 0.43 to 0.85; P=.003). Carriers of the CYP2C9*2 or *3 allele needed a significantly lower phenprocoumon dosage compared with homozygous CYP2C9*1/*1 subjects. CONCLUSION: The presence of at least 1 CYP2C9*2 or *3 allele in phenprocoumon users is associated with an increased risk of severe overanticoagulation. Similar to warfarin and acenocoumarol, phenprocoumon had a lower dosage requirement in carriers of CYP2C9*2 or *3 compared with that in CYP2C9 wild-type subjects.

Aged↗
PubMed2004

Pharmacological treatment in patients with heart failure: patients knowledge and occurrence of polypharmacy, alternative medicine and immunizations.

AIMS: To evaluate in patients with heart failure (HF) due to systolic dysfunction the occurrence of polypharmacy, alternative medicine, immunization against influenza, and patients' knowledge about their medication. METHODS AND RESULTS: Sixty-five patients, 49 men, mean age 60.5+/-12.0 years answered a confidential questionnaire during 2002. Polypharmacy was frequent, 48 (74%) were taking six or more pills per day and 18 (28%) 11 or more. Fifteen patients (23%) used over-the-counter analgesics. Eight patients (12%) used alternative medicine [five women (31%) vs. three men (6%), P=0.02]. Forty-four patients (68%) received immunization against influenza (18 patients <65 years (54%) vs. 25 patients > or =65 years (79%), P=0.03). Half the patients knew that beta-blockers and vasodilators decreased blood pressure, 31 patients receiving diuretics (88%) knew that this drugs help to eliminate liquids, 12 patients (38%) recognized this effect with low dose spironolactone and 23% or less with other drugs. Only 12 patients (42%) treated with acenocoumarol and 13 of those treated with aspirin (32%) recognized the action of these drugs. CONCLUSION: Patients with HF and systolic dysfunction have a poor knowledge about the medication they receive. Polypharmacy, over-the-counter, homeopathic and alternative medicine use is frequent whereas the rate of immunization against influenza is low.

Adult↗
PubMed2004

Low molecular weight heparin (dalteparin) is equally effective as unfractionated heparin in reducing coagulation activity and perfusion abnormalities during the early treatment of pulmonary embolism.

Little is known about the differences between unfractionated heparin (UFH) and low molecular weight heparin (LMWH) with regard to their effects on coagulation activity during treatment for pulmonary embolism. The objective of this study was to compare UFH and LMWH (dalteparin) in the early treatment of pulmonary embolism in terms of control of coagulation markers and perfusion abnormalities. Thirty-seven patients with acute pulmonary embolism were randomized to receive intravenous UFH or subcutaneous dalteparin, each accompanied by acenocoumarol. Daily blood samples were obtained for the measurement of thrombin generation (fragments 1 and 2 [F1+2], thrombin-antithrombin (TAT) complexes and fibrin monomers [FMs]) and fibrinolysis (d-dimer concentrations and clot-lysis times). Ventilation-perfusion scintigraphies were performed, and with the data they yielded, percentage of vascular obstruction scores (PVOs) were calculated on days 0 and 5. The international normalized ratio was within the therapeutic range in both groups on day 3. F1+2 and TAT complexes rapidly normalized, without differences between the groups (P =.5 and.4, respectively). FM levels did not decrease and, in fact, showed an increase in the UFH group from day 3 on (P <.05 between groups). d-Dimer levels decreased over time, with no differences between groups (P =.6). Clot-lysis times were shorter in the UFH group (P <.05). PVOs on days 0 and 5 were not different (P =.5 and.8, respectively), but the decrease in PVOs over time was greater in the dalteparin group (P =.04). These results show that dalteparin is at least as effective as UFH in reducing coagulation activity and perfusion abnormalities in the early treatment of pulmonary embolism.

Adult↗
PubMed2006

[Vitamin K epoxide reductase: Fresh blood for oral anticoagulant therapies].

INTRODUCTION: Vitamin K epoxide reductase complex subunit I (VKORC1) is a key enzyme in the vitamin K cycle, cofactor required for the activation of vitamin K-dependent clotting factors. EXEGESIS: VKORC1 recycles vitamin K 2,3 epoxide back to active vitamin K hydroquinone, an important factor for the carboxylation step of clotting factors. VKORC1 is the target enzyme of inhibition by oral anticoagulants or anti-vitamin K (warfarin, acenocoumarol). CONCLUSION: We show here the clinical consequences of genetic variations of VKORC1 during VKA therapy.

Administration, Oral↗
PubMed2005

Correlation of plasma von Willebrand factor levels, an index of endothelial damage/dysfunction, with two point-based stroke risk stratification scores in atrial fibrillation.

To test the hypothesis that the new CHADS2 and Framingham point-based risk stratification scores could be related to plasma vWf (a plasma index of endothelial damage/dysfunction) and soluble E-selectin (an index of endothelial activation) levels in a large cohort of AF patients, we studied 200 consecutive patients (101 male; 72+/-9 years) attending our anti-coagulation clinic for the initiation of anticoagulation treatment with acenocoumarol. AF patients had a median CHADS2 score of 2 (1-2) and a median Framingham point-based risk score of 14 (9-21). Results of research indices in our AF patients were as follows: vWf 142.8+/-41.8 IU/dL and sE-sel 44 (31-62) ng/mL. There were significant correlations between plasma vWf levels and both risk CHADS2 and Framingham risk scores (vWf-CHADS2 risk score: Spearman, r=0.249, p<0.001; vWf-Framingham risk score: r=0.294, p<0.001). sE-sel did not show any significant correlation with both risk scores (sE-sel-CHADS2 risk score: r=-0.054, p=0.460; sE-sel-Framingham risk score: r=0.062, p=0.460). There were no statistically significant correlations between vWf and sE-sel (r=-0.127, p=0.081). Both CHADS2 and Framingham risk scores were significantly correlated with each other, r=0.627, p<0.001. In conclusion, in a wide cohort of non-selected and consecutive AF patients, endothelial damage/dysfunction (assessed by plasma vWf levels) but not endothelial activation (sE-sel) correlated with two new risk stratification scores for stroke in AF. Further prospective studies are needed to assess the prognostic role of prothrombotic indices in AF in relation to stroke and thromboembolic events, and their role in complementing clinical risk stratification schemas.

Aged↗
PubMed2001

Recombinant factor VIIa (Novoseven) restores deficient coagulation: experience from an ex vivo model.

The action of recombinant factor VIIa (rFVIIa) in coagulation deficiencies with increased risk of bleeding was investigated using in vitro perfusion. Blood samples were drawn from healthy donors, a patient with hemophilia A and inhibitors, and six patients undergoing oral anticoagulant treatment. Fragmin 10 U/mL was used as anticoagulant. rFVIIa (10 microg/mL in plasma) was added to blood samples, incubated for 1 minute at 37 degrees C, and perfusion studies performed for 10 minutes at 600 x s(-1) through annular chambers containing damaged vascular segments. Subendothelial fibrin and platelets were expressed as a percentage of subendothelial surface screened. Under different conditions, rFVIIa consistently restored or improved fibrin formation on the damaged vascular subendothelium exposed to circulating blood. It restored fibrin deposition in blood from the hemophilia A patient; in patients undergoing acenocoumarol treatment, it reduced the international normalized ratio (INR) from 2.47 to 1.25 with a significant increase in fibrin deposition. Platelet deposition varied slightly between clinical conditions but was less evident in the hemophilia A patient. These data support the concept that rFVIIa facilitates fibrin formation in these clinical situations, promoting procoagulant activity at sites of vascular damage where tissue factor is exposed. This could improve hemostasis in patients with hemophilia A and inhibitors, and in patients treated with oral anticoagulants.

Adult↗
PubMed2003

[Pharmacological interactions of statins].

OBJECTIVE: To determine in primary care the frequency of pharmacological interactions of statins. DESIGN: Transversal observational study.Setting. Urban health centre.Participants. 384 patients taking statins who were chosen by systematic sampling based on long-treatment cards (95% CI, accuracy 5% and expected proportion of possible interactions unknown). MAIN MEASUREMENTS: Consumption of statins, the accompanying medication taken, presence of interactions according to the technical details of statins (Spanish Medication Agency, Ministry of Health and Consumption) and social and demographic variables. RESULTS: In 55 patients (14.3%) (95% CI, 10.8%-17.8%) one of the statin interactions with the other drugs was checked, especially with acenocoumarol, digoxin and anti-acid drugs. In patients with some interaction, the mean number of other drugs was significantly higher (4.51.5 vs 3.31.9 SD; P<.001). 19.1% of men and 10.8% of women showed interactions, the difference being statistically significant (P=.02). By means of logistic regression, both masculine gender (OR=1.8) and taking of other medication in quantities of 5 or more (OR=2.7) appeared as variables associated with the presence of interactions. CONCLUSIONS: The potential pharmacological interactions of statins reach 14.3% of patients with hypercholesterolaemia who take medication long-term. The possibility of reaching high plasma concentrations of statins and/or of modifying the therapeutic effect of various drugs enables a more appropriate use of statins to be recommended, with prescription of those statins that metabolise less through the P450 cytochrome.

Adult↗
PubMed1998

Detection of 4-hydroxycoumarin anticoagulants and their metabolites in urine as part of a systematic toxicological analysis procedure for acidic drugs and poisons by gas chromatography-mass spectrometry after extractive methylation.

A gas chromatography-mass spectrometry (GC-MS) procedure was developed for the detection of 4-hydroxycoumarin anticoagulants and their metabolites in urine as part of a systematic toxicological analysis procedure for acidic drugs and poisons after extractive methylation. The part of the phase-transfer catalyst remaining in the organic phase was removed by solid-phase extraction on a diol phase. The compounds were separated by capillary GC and identified by computerized MS in the full scan mode. Using mass chromatography with the ions m/z 291, 294, 295, 309, 313, 322, 324, 336, 343 and 354, the possible presence of 4-hydroxycoumarin anticoagulants and/or their metabolites could be indicated. The identity of positive signals in such mass chromatograms was confirmed by comparison of the peaks underlying full mass spectra with the reference spectra recorded during this study. This method allowed the detection of therapeutic concentrations of phenprocoumon and warfarin in human urine samples. In absence of human urine, acenocoumarol, coumachlor, coumatetrayl, pyranocoumarin (cyclocumarol) could be detected only in rat urine.

4-Hydroxycoumarins↗
PubMed1991

[Thrombocytopenia induced by low molecular weight heparin during hypotensive and diuretic treatment: coincidence or connection?].

A case is reported of a 70-year-old female who presented with early thrombocytopaenia, apparently induced by a low molecular weight heparin. The patient was admitted with anasarca. The initial treatment consisted in digoxin, furosemide, potassium canrenoate and aldactone, and 0.3 ml of Fraxiparine daily, which replaced acenocoumarol. She had never been given any heparin previously. On the fourth day, her platelet count had dropped from 210 G.1-1 to 122 G.1-1, and to 15 G.1-1 on the sixth day. Heparin administration had been stopped on the fourth day, and the platelet count had returned to 141 G.1-1 five days later. Similar cases of such an early thrombocytopaenia have been reported in patients also taking diuretics and hypotensive drugs. However, a relationship between the two facts cannot yet be ascertained.

Adverse Drug Reaction Reporting Systems↗
PubMed1992

[Disclosure of protein C deficiency with pulmonary embolism followed by cardiac arrest during the recovery period].

A case of unexpected cardiac arrest occurring in a 17-year-old male patient is reported. The patient had been admitted after sustaining hand trauma. A first emergency surgical procedure was carried out, followed about three weeks later by another one. No incidents occurred during or after either of these two operations. A third procedure was required about two months after the accident (free toe graft to the thumb of the left hand). The twelve-hour operation was carried out under general anaesthesia and axillary block. The patient was given intravenous heparin (800 IU.h-1) during the procedure on the arm. The patient recovered quickly, and was extubated before his transfer to the recovery room. Fifteen minutes later, the patient's heart rate decreased to 40 b.min-1, followed by a transient cardiorespiratory arrest. The suspicion of pulmonary embolism was confirmed by pulmonary scintigraphy. Thrombolysis was carried out with 2,000 IU.kg-1.h-1 of urokinase for a 72 h period, combined with continuous heparin administration (16 to 36 x 10(3) IU.day-1). The patient recovered after one week. No thrombophlebitis was found for origin of the emboli. Biological investigations carried out both before and after 10 minutes of anoxia revealed a normal fibrinolytic system, but a deficit in protein C (62% antigen, 64% activity). Two years after the episode of pulmonary embolism, the patient, still taking acenocoumarol, remained free from any sequela. Current perioperative management of patients with a known protein C deficit is discussed.

Adult↗
PubMed1998

New bronchodilators selected by molecular topology.

Molecular topology has been applied to find new lead compounds with bronchodilator activity. Among the selected compounds stands out 3-(1H-tetrazol-5yl)-9H-thioxanthene-9 -one-10,10-dioxide, anthrarobin, 9-oxo-9H-thioxantene-3-carboxylic-10,10-dioxide acid, acenocoumarol and griseofulvin, with a percentage of relaxation, at 0.1 mM, of 91, 92, 85, 69, and 74%, respectively. Theophylline shows a correspondent value of 77% (Emax = 100% at 1 mM).

Animals↗
PubMed2000

Stabilization of oral anticoagulant therapy in hospitalized patients and characteristics associated with lack of stabilization.

The initiation and stabilization of oral anticoagulant therapy in hospitalized patients in a setting without specialized medical or pharmaceutical advice, was studied. In addition, potential risk factors for lack of stabilization were studied. All patients from three wards (orthopaedic surgery, general surgery and internal medicine) in two Dutch hospitals, who were started on oral anticoagulant therapy and who gave informed consent, were included in this three months prospective follow-up study. When a patient had two consecutive INR's within the range 2-3 during hospitalization (on day 6 or later), he was defined as stable. Stable and unstable patients were compared with respect to age, gender, quetelet index, length of hospital stay, indication for oral anticoagulant therapy, induction dosing schedule of oral anticoagulant therapy, prescribing physician, type of hospital (teaching or non-teaching), concurrently used drugs, concurrently used drugs known to potentially interact with oral anticoagulant therapy (drug-drug interactions that influence INR) and (co)morbidity. A total of 125 patients, who all used acenocoumarol as oral anticoagulant, were recruited in the study. The study population mainly comprised orthopaedic discharges on prophylactic oral anticoagulants. The mean length of hospital stay was 14.5 days (median 11.0, standard deviation (SD) 10.2) for the patients included in the study (patients with a short length of stay < 6 days were excluded from the study, because of the definition of stability). 43 patients (34%) became stable during hospitalization. The second INR within the range was reached after on average 11.1 days (median 10.0, SD 4.5). 18 different induction dosing schedules were used. Differences in apparent risk of INR instability were statistically associated with length of hospital stay (odds ratio (OR) 0.85, 95% confidence interval (CI) 0.78-0.92), concurrent use of musculoskeletal drugs, mainly NSAIDs, (OR 1.68, 95% CI 1.04-2.72) and two individual prescribing physicians (OR 6.61, 95% CI 1.47-29.82 for one physician and OR 0.23, 95% CI 0.06-0.99 for the other physician). This population has a high percentage of instability and reaches stability relatively late. The instability was associated with length of hospital stay, the concurrent use of musculoskeletal drugs (mostly NSAID's) and physician. Most of the unstable patients had INR's below therapeutic range, suggesting a conservative dosing habit. Part of the instability may also be due to the many different physicians who dose their own patients. Interventions to improve dosing may aid in better stabilization in hospitalized patients and thus in reduced length of hospital stay.

Administration, Oral↗
PubMed2000

Antiplatelet therapy alters iron requirements in hemodialysis patients.

Hemodialysis (HD) patients are prone to develop iron deficiency because of consumption of iron stores during erythropoietin (EPO) therapy. Data are needed to establish the factors involved in the different iron needs among these patients. Sixty-five HD patients were prospectively studied during a year. The subjects were dialyzed through polytetrafluoroethylene (PTFE) grafts (n = 23), arteriovenous native fistulae (n = 41), and a Permcath (n = 1). Twenty-four patients were administered aspirin; 23 patients, ticlopidine; 1 patient, dipyridamole; and 4 patients, anticoagulation with acenocoumarol. Iron supplementation (oral or parenteral) and laboratory parameters were recorded monthly. Significant differences in iron requirements, depending on the use of antiplatelet and/or anticoagulation agents, were found. Total parenteral iron supplements were greater in patients on antiplatelet therapy with either native or graft vascular accesses compared with the rest (2,406 +/- 1,445 versus 1,562 +/- 858 mg; P = 0.0081). Twelve of 52 patients on antiplatelet therapy required oral iron and only 1 of 13 patients not on antiplatelet therapy was administered oral iron supplements (P < 0.05). Patients on antiplatelet therapy were administered more transfusions (1.9 +/- 3.8 transfusions/y) than individuals not on antiplatelet therapy (0.15 +/- 0.3 transfusions/y; P = 0.0015). However, only patients with PTFE grafts on antiplatelet therapy had a post-HD bleeding time longer than patients not on antiplatelet therapy (9.1 +/- 3.6 versus 5.7 +/- 3.9 minutes; P < 0.0001). Multiple logistic regression analysis showed that the use of antiplatelet agents (P < 0.05) is an independent factor that increased the probability of requiring greater parenteral iron supplements (>2.5 g/y). Patients with PTFE grafts required more EPO than those with autologous fistulae (160 +/- 93 versus 100 +/- 63 U/kg/wk; P = 0.012). No differences between groups were found that could explain this finding. Antiplatelet and/or anticoagulation therapy implied the use of greater amounts of iron supplements in HD patients. Although these greater requirements of iron occurred in parallel with bleeding from the vascular access, additional data favor the existence of other factors, eg, interdialytic blood losses. The present study suggests that antiplatelet therapy may be an important factor in determining iron requirements in HD patients. Moreover, our data relate for the first time the use of prosthetic grafts with increased EPO requirements, an issue of great potential importance in the debate about vascular access policy in dialysis units.

Administration, Oral↗