Monitoring Warfarin Therapy with the International Normalized Ratio

1994 ◽  
Vol 28 (2) ◽  
pp. 242-244 ◽  
Author(s):  
Patricia A. Howard
Keyword(s):  
Ct Scan ◽  
Heart Valves ◽  
Warfarin Therapy ◽  
Medical Center ◽  
Current System ◽  
International Normalized Ratio ◽  
Bleeding Complications ◽  
Warfarin Dosage ◽  
Local Hospital ◽  
Traditional System

OBJECTIVE: To report a case of suboptimal warfarin monitoring. CASE SUMMARY: A patient with a history of rheumatic heart disease and a mechanical mitral valve was admitted to the local hospital complaining of left-sided weakness. At the time, she was receiving warfarin 5 mg/d. Upon admission her prothrombin time (PT) was 15 s. An initial computed tomography (CT) scan of the head was negative. On the basis of the initial findings, it was unclear whether the symptoms were caused by a cerebrovascular accident (CVA). The patient was transferred to the University Medical Center for a more thorough evaluation. The diagnosis of CVA was confirmed by a repeat CT scan seven days after the event. On the basis of the information obtained from the local hospital, it was determined that the initial PT of 15 s converted to an International Normalized Ratio (INR) of 1.5, which is below the recommended range for patients with mechanical heart valves. Prior to discharge, the warfarin dosage was increased to obtain an INR in the recommended range of 2.5–3.5. DISCUSSION: This case illustrates the problems that exist with the current system of PT reporting and the potential advantages of using the INR. Variations in the sensitivity of the thromboplastin reagents used to perform the PT may result in misinterpretation of the level of anticoagulation and errors in warfarin dosage adjustments. The potential for suboptimal anticoagulation is greatly increased in patients, such as the one reported here, who are having PTs performed by multiple laboratories. CONCLUSIONS: To maximize efficacy and minimize the risk of bleeding complications, warfarin therapy must be individualized and closely monitored. Standardization of PT monitoring through the use of the INR would significantly reduce the potential for suboptimal anticoagulation associated with the traditional system of reporting.

Association between VEGFA gene polymorphisms and bleeding complications in patients maintaining therapeutic international normalized ratio

2019 ◽  
Vol 20 (9) ◽  
pp. 659-667 ◽  
Author(s):  
Jeong Yee ◽  
Woorim Kim ◽  
Byung Chul Chang ◽  
Jee Eun Chung ◽  
Kyung Eun Lee ◽  
...  
Keyword(s):  
Gene Polymorphisms ◽  
Bleeding Complication ◽  
Heart Valves ◽  
Warfarin Therapy ◽  
International Normalized Ratio ◽  
Mechanical Heart Valves ◽  
Bleeding Complications ◽  
Wild Type ◽  
Vegfa Gene

Aim: This study was designed to identify the possible effects of VEGFA polymorphisms on the occurrence of bleeding complications in patients with mechanical heart valves who have achieved therapeutic international normalized ratio (INR). Materials & methods: 13 SNPs of VEGFA were analyzed. Uni- and multi-variate analyses were conducted to identify associations between polymorphisms and bleeding complications. Results & conclusion: Patients with the CC genotype of rs35410204 had an approximately tenfold higher bleeding complication than those with the T allele. For rs866236, patients who had wild-type homozygotes showed an approximately 2.9-fold higher bleeding complication than C allele carriers. This study demonstrated that bleeding complications during warfarin therapy are associated with VEGFA polymorphisms in patients with mechanical heart valves.

Fenofibrate Potentiates Warfarin Effects

2003 ◽  
Vol 37 (2) ◽  
pp. 212-215 ◽  
Author(s):  
Karissa Y Kim ◽  
Michael A Mancano
Keyword(s):  
White Woman ◽  
Chart Review ◽  
Warfarin Therapy ◽  
Dosage Reduction ◽  
International Normalized Ratio ◽  
Drug Regimen ◽  
Warfarin Dosage ◽  
Therapeutic Doses ◽  
Anticoagulant Response

OBJECTIVE: To describe 2 patients in whom the initiation of fenofibrate potentiated warfarin's anticoagulant effects. CASE SUMMARY: A 71-year-old white woman and an 80-year-old white woman with multiple medical conditions were both stabilized on long-term warfarin therapy. During the course of anticoagulation, both patients were prescribed fenofibrate and experienced threefold and twofold increases in international normalized ratio (INR), respectively, requiring total weekly warfarin dosage reductions of 30–40%. Before starting fenofibrate therapy, both patients' coagulation values were within the therapeutic range. When interviewed, patients and caregivers denied bleeding, bruising, changes in diet, alcohol ingestion, nonadherence with therapy, or changes in drug regimen except for the addition of fenofibrate. Upon chart review, evaluation of potentially contributory parameters, such as other changes in drug therapy, thyroid function, liver function, and drug–disease interactions, showed that these parameters remained stable and were ruled noncontributory. DISCUSSION: The addition of fenofibrate in 2 patients on stable and therapeutic doses of warfarin increased the anticoagulant response to warfarin. A clear temporal relationship with the addition of fenofibrate and the appearance of the interaction was seen. Fenofibrate is highly protein bound, with the potential to displace warfarin from its binding protein, leading to an enhanced hypoprothrombinemic effect. Fenofibrate is also a mild to moderate inhibitor of CYP2C9, the enzyme responsible for warfarin metabolism. The combination of these effects — displacement of warfarin by fenofibrate coupled with decreased metabolism of warfarin — may increase the anticoagulant response to warfarin. Using the Naranjo probability scale, these interactions were designated as probable. CONCLUSIONS: We suggest serial monitoring of INR and consider an empiric 20% reduction in warfarin dosage when fenofibrate is initiated, with the possibility for a greater warfarin dosage reduction based on INR results.

scholarly journals Effects of Polymorphisms in Myc-Related Genes on Bleeding Complications in Patients with Stable Warfarin Responses

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Jeong Yee ◽  
Woorim Kim ◽  
Byung Chul Chang ◽  
Jee Eun Chung ◽  
Kyung Eun Lee ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Degrees Of Freedom ◽  
Heart Valves ◽  
Warfarin Therapy ◽  
Attributable Risk ◽  
Bleeding Complications ◽  
Nucleotide Polymorphisms ◽  
Analysis Model ◽  
Clinical Value ◽  
Increased Risk

Objectives. This study aimed to identify the possible effects of Myc and 8q24 polymorphisms on bleeding complications in patients who maintained international normalized ratio (INR) of 2.0-3.0 with warfarin therapy after cardiac valve replacement. Methods. Twenty-five single nucleotide polymorphisms were analyzed, including VKORC1, CYP2C9, Myc, and 8q24. Univariate and multivariate analyses were conducted to evaluate the associations between genetic polymorphisms and bleeding complications. Attributable risk and the number needed to genotype (NNG) were also calculated to evaluate the potential clinical value of genotyping. Results. We included 142 patients, among whom 21 experienced bleeding complications. Multivariate models showed that patients carrying the CC genotype of rs6983561 and the A allele of rs13281615 at 8q24 had 27.6- and 10.0-fold higher bleeding complications, compared with patients with the A allele and the GG genotype, respectively. For rs6983561, the attributable risk and NNG were 96.4% and 36.8, respectively, whereas, for rs13281615, the attributable risk and NNG were 90.0% and 8.3, respectively. Atrial fibrillation was associated with a 5.5-fold increased risk of bleeding complications. The AUROC value was 0.761 (95% CI 0.659-0.863, p<0.001), and the Hosmer–Lemeshow test showed that the fitness of the multivariate analysis model was satisfactory (χ2=0.846; 3 degrees of freedom; p=0.838). Conclusions. Bleeding complications during warfarin therapy were associated with 8q24 polymorphisms and atrial fibrillation in patients with mechanical heart valves.

scholarly journals A Review of Warfarin Dosing and Monitoring

2018 ◽  
Vol 13 (1) ◽  
pp. 40-43 ◽  
Author(s):  
Khan Md Arif ◽  
Mohammad Ashiqur Rahman
Keyword(s):  
Venous Thromboembolism ◽  
Heart Valves ◽  
Warfarin Therapy ◽  
Thrombus Formation ◽  
Therapeutic Index ◽  
International Normalized Ratio ◽  
Major Surgery ◽  
Clotting Factors ◽  
Duration Of Treatment ◽  
Oral Anticoagulant Treatment

The anticoagulant drug warfarin is a vitamin K antagonist, coumarin derivative which inhibits the synthesis of clotting factors II, VII, IX, and X, as well as the naturally occurring endogenous anticoagulant proteins C and S. Warfarin is still considered the mainstay of oral anticoagulant treatment, it is a difficult drug to manage due to its narrow therapeutic index. An inappropriate management of patients can lead to subtherapeutic or supratherapeutic levels, increasing the risk of thromboembolic episodes or hemorrhagic episodes, respectively. Common indications for the use of warfarin include stroke prevention in atrial fibrillation, preventing thrombus formation in patients with heart valves and treatment of venous thromboembolism. When warfarin therapy is initiated for venous thromboembolism, it should be given the first day, along with a heparin product or fondaparinux. The heparin product or fondaparinux should be continued for at least five days and until the patient's international normalized ratio is at least 2.0 for two consecutive days. The international normalized ratio goal and duration of treatment with warfarin vary depending on indication and risk. Warfarin therapy should be stopped five days before major surgery and restarted 12 to 24 hours postoperatively. Bridging with low-molecular-weight heparin or other agents is based on balancing the risk of throm boembolism with the risk of bleeding.Faridpur Med. Coll. J. Jan 2018;13(1): 40-43

Khat Chewing Effect on the International Normalized Ratio in Patients with Mechanical Heart Valves under Warfarin Therapy

2020 ◽  
Vol 23 (11) ◽  
pp. 1487-1491
Author(s):  
Sultan Abdulwadou ◽  
Nouradden Noman Alja ◽  
Abdulwahab Omer Hussa ◽  
Khalid Mohammed A ◽  
Suliman Gafar Sali
Keyword(s):  
Heart Valves ◽  
Warfarin Therapy ◽  
International Normalized Ratio ◽  
Mechanical Heart Valves ◽  
Khat Chewing

Optimization of Inpatient Warfarin Therapy: Impact of Daily Consultation by a Pharmacist-Managed Anticoagulation Service

2000 ◽  
Vol 34 (5) ◽  
pp. 567-572 ◽  
Author(s):  
William E Dager ◽  
Jennifer M Branch ◽  
Jeffrey H King ◽  
Richard H White ◽  
Richard S Quan ◽  
...  
Keyword(s):  
Warfarin Therapy ◽  
Anticoagulation Therapy ◽  
Cost Savings ◽  
Length Of Hospital Stay ◽  
International Normalized Ratio ◽  
Pharmacist Intervention ◽  
University Teaching ◽  
Bleeding Complications ◽  
Number Of Patients ◽  
First Time

OBJECTIVE: To determine the effect of daily consultation by a team of hospital pharmacists on the accuracy and rapidity of optimizing warfarin therapy. DESIGN: Comparison of a historical control cohort with a prospective cohort matched for treatment indication. SETTING: A 400-bed university teaching hospital. PATIENTS: Sixty consecutive patients hospitalized in 1992 and starting warfarin for the first time, with anticoagulation therapy managed by physicians, were compared with 60 patients matched for warfarin indication hospitalized in 1995, but with anticoagulation therapy managed with pharmacy consultation. RESULTS: Pharmacist management of initial warfarin therapy resulted in a significant reduction in the length of hospitalization compared with physician dosing, from 9.5 ± 5.6 days to 6.8 ± 4.4 days (p = 0.009). The number of patients and patient-days with international normalized ratio (INR) values >3.5 were reduced by pharmacist dosing from 37 patients and 142 days to 16 patients and 29 days, respectively (p < 0.001). Similarly, the number of patients and patient-days with INR >6.0 were reduced from 20 patients and 50 days to two patients and six days, respectively (p < 0.001). There were six documented bleeding complications in 1992 compared with one in 1995 (p = 0.11). The mean INR at discharge was significantly lower in the pharmacy surveillance group, 2.6 ± 0.58, compared with the physician cohort, 3.3 ± 2.1 (p = 0.07). Readmissions after discharge due to bleeding or recurrent thrombosis were reduced from five (at 1 mo) and 10 (at 3 mo) to two and five readmissions, respectively, by pharmacist intervention (p = 0.43). The number of patients with concurrently prescribed drugs known to significantly interact with warfarin was significantly lower (6 vs. 13; p = 0.02) in the pharmacy surveillance group. CONCLUSIONS: Among patients starting warfarin for the first time, daily consultation by a pharmacist significantly decreased the length of hospital stay and the number of patients who received excessive anticoagulation therapy. These findings translate into improved quality of care and potentially significant cost savings.

Venous Thromboembolism and High Grade Gliomas

1993 ◽  
Vol 70 (03) ◽  
pp. 393-396 ◽  
Author(s):  
Mandeep S Dhami ◽  
Robert D Bona ◽  
John A Calogero ◽  
Richard M Hellman
Keyword(s):  
Risk Factors ◽  
Venous Thromboembolism ◽  
Medical Center ◽  
Significant Risk ◽  
Bleeding Complications ◽  
Fisher Exact Test ◽  
High Grade ◽  
Chi Square ◽  
Exact Test ◽  
High Grade Gliomas

SummaryA retrospective study was done to determine the incidence of and the risk factors predisposing to clinical venous thromboembolism (VTE) in patients treated for high grade gliomas. Medical records of 68 consecutive patients diagnosed and treated at Saint Francis Hospital and Medical Center from January 1986 to June 1991 were reviewed. The follow up was to time of death or at least 6 months (up to December 1991). All clinically suspected episodes of VTE were confirmed by objective tests. Sixteen episodes of VTE were detected in 13 patients for an overall episode rate of 23.5%. Administration of chemotherapy (p = 0.027, two tailed Fisher exact test) and presence of paresis (p = 0.031, two tailed Fisher exact test) were statistically significant risk factors for the development of VTE. Thrombotic events were more likely to occur in the paretic limb and this difference was statistically significant (p = 0.00049, chi square test, with Yates correction). No major bleeding complications were seen in the nine episodes treated with long term anticoagulation.We conclude that venous thromboembolic complications are frequently encountered in patients being treated for high grade gliomas and the presence of paresis and the administration of chemotherapy increases the risk of such complications.

Sistem Integrasi Aplikasi Desktop Klinik MCU TKI Pada Medical Center Purwokerto

2020 ◽  
Vol 2 (01) ◽  
pp. 1-8
Author(s):  
Lutfi Syafirullah ◽  
Hidayat Muhammad Nur ◽  
Vadlya Ma'arif
Keyword(s):  
Network Architecture ◽  
Clinical Information System ◽  
Medical Center ◽  
Current System ◽  
Clinical Information ◽  
Clinical Work ◽  
Database Systems ◽  
Prototype Model ◽  
Medical Checkup ◽  
Operational Activities

Information technology integration is expected to be able to accommodate the ease and improvement in supporting database platforms through intranet and internet infrastructure. Integration is intended to blend desktop and web database systems. Medical Checkup Purwokerto is a designated place to facilitate the checkup health of the official PJTKI Banyumas Disnaker BNP2TKI. The current system, which is a check-up application, is carried out by prospective Indonesian Workers or Medical checkup units, covering many processes including registration, health checks, types, results, payments and reports. There was a buildup of operational activities Clinical work on a daily basis, by the administrator of the medical record so that management aimed at developing a web-based clinical information system includes the scope of the processed database components, access authorization, and security. The method used is the software development life cycle (SDLC) with the Evolutionary Prototype Model. Results, patient data can be integrated as a whole process flow with a client-server network architecture

scholarly journals Risk factors for cerebral vasospasm in patients with aneurysmal subarachnoid hemorrhage

Open Medicine ◽  
2020 ◽  
Vol 15 (1) ◽  
pp. 598-604
Author(s):  
Valentina Opancina ◽  
Snezana Lukic ◽  
Slobodan Jankovic ◽  
Radisa Vojinovic ◽  
Milan Mijailovic
Keyword(s):  
Risk Factors ◽  
Subarachnoid Hemorrhage ◽  
Cerebral Vasospasm ◽  
Aneurysmal Subarachnoid Hemorrhage ◽  
Medical Center ◽  
White Blood Cells ◽  
Cerebral Aneurysms ◽  
International Normalized Ratio ◽  
Cross Sectional Study ◽  
Cross Sectional

AbstractIntroductionAneurysmal subarachnoid hemorrhage is a type of spontaneous hemorrhagic stroke, which is caused by a ruptured cerebral aneurysm. Cerebral vasospasm (CVS) is the most grievous complication of subarachnoid hemorrhage (SAH). The aim of this study was to examine the risk factors that influence the onset of CVS that develops after endovascular coil embolization of a ruptured aneurysm.Materials and methodsThe study was designed as a cross-sectional study. The patients included in the study were 18 or more years of age, admitted within a period of 24 h of symptom onset, diagnosed and treated at a university medical center in Serbia during a 5-year period.ResultsOur study showed that the maximum recorded international normalized ratio (INR) values in patients who were not receiving anticoagulant therapy and the maximum recorded white blood cells (WBCs) were strongly associated with cerebrovascular spasm, increasing its chances 4.4 and 8.4 times with an increase of each integer of the INR value and 1,000 WBCs, respectively.ConclusionsSAH after the rupture of cerebral aneurysms creates an endocranial inflammatory state whose intensity is probably directly related to the occurrence of vasospasm and its adverse consequences.

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