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Medication Safety: Anticoagulation Management (Text Version)

Slide presentation from the AHRQ 2008 conference showcasing Agency research and projects.

Slide Presentation from the AHRQ 2008 Annual Conference

On September 8, 2008, Carla S. Huber, ARNP MS, made this presentation at the 2008 Annual Conference. Select to access the PowerPoint® presentation (4.6 MB).

Slide 1

Medication Safety: Anticoagulation Management

Carla S. Huber, ARNP MS
Community Anticoagulation Therapy (CAT) Clinic
Cedar Rapids, IA 52401

Slide 2


  • Identify the challenges and barriers to implementing medication safety tools
  • Explain the importance of utilizing evidence-based guidelines for managing warfarin therapy
  • Explain the importance of education for patients taking warfarin
  • List the advantages of a dedicated anticoagulation clinic

Slide 3

Partnerships in Implementing Patient Safety (PIPS) Grant

  • Specific Aims:
    • Education and training in principles of International Organization for Standardization (ISO) 9001 quality management systems.
    • Establish the anticoagulation clinic.
    • Determine other uses of ISO framework within the healthcare community.

Slide 4

The line graph presents the percentage of Warfarin of All adverse drug events (ADEs) from 04/02 through 11/04. The vertical axis goes from 0% to 40% and the horizontal axis shows the dates of Oct-02 through Oct-04. The line graph starts at 25% in Oct-02, reaches a maximum of 37% in Feb-03, a low of 7% in Oct-03, and ends at 27% in Oct-04.


  • Also, many studies that support organized management of blood thinning medications.

Slide 5

National Quality Forum (NQF) (2004)

  • Safe Practices:
    • #1—Creation of a healthcare culture of safety
    • #18—Utilization of dedicated anti-thrombotic services that facilitate coordinated care management

Slide 6

Medication Statistics

  • 60% of older Americans use five or more different medications per week.
  • 20% of older Americans take 10 different medications per week.
  • Americans older than 65 have more than 175,000 emergency room visits/year for adverse drug events.

Slide 7

Medication Statistics

  • In the U.S. age >65 comprise 15% of population and buy 30% of all prescription drugs and 40% of over-the-counter (OTC) meds:, retrieved 1/22/07
  • Up to 60% of all medications prescribed are taken incorrectly or not at all
  • 90% of elderly patients make some medication errors
  • 35% of the elderly make potentially serious errors:, retrieved 1/12/07


  • Recently pt's. International Normalized Ratio (INR) in range for 7 mos. Pt. picked up new prescription of warfarin that read take 5mg, M,F and 7.5mg other days/week, even though she had been taking 5mg four days/week and 7.5mg 3 days/week for 7 mos, INR up to 5.6.
  • Pt taking warfarin bid because her blood pressure (BP) pill that she took in am that was peach in color and her warfarin was peach in color. So she was taking warfarin twice a day instead of BP in AM and warfarin in PM.

Slide 8

Anticoagulation Clinics

  • Dedicated service to manage patients on anticoagulation medications
  • Use evidence based guidelines to make dosing decisions
  • Specially trained nurses, pharmacists
  • Decrease complications of anticoagulants and decrease emergency room (ER) visits and hospital admissions
  • Pts. are in INR range greater percent of the time
  • Improve physician and staff efficiency


  • Consistency in training and staff. Look at how differently physicians practice. Again no different than congestive heart failure (CHF) or pneumonia guidelines.
  • Collecting data.

Slide 9

Why dedicated anticoagulation clinics?

  • Use of evidence-based guidelines—American College of Chest Physicians (ACCP).
  • Improved outcomes:
    • Increased time in INR range
    • Decreased bleeding and clotting events
    • Decreased hospitalizations related to anticoagulation events

Slide 10

Patient Safety Goal

  • Joint Commission (JCAHO) 2009 National Patient Safety Goal #3:
    • Improve the safety of using medications
    • Anticoagulation therapy, 3.05.01
      • Reduce the likelihood of patient harm associated with the use of anticoagulation therapy

Slide 11

Why ISO 9001

  • An organized Quality Management System:
    • "Say what you do"
  • Document what you do:
    • "Do what you say"
  • Perform to your documentation:
    • "Record Information"
  • Record the results of your work:
    • "Audit effectiveness"
  • Audit the documentation of effectiveness.


  • How many of us work in settings where same policies are different for other departments, registration for instance. Or policies are written in different formats for different departments.

Slide 12

Policies and Procedures

  • The organization needs to identify and determine which additional procedures need to be documented to create consistent processes.
  • Physicians' Clinic of Iowa (PCI) currently has over 400 documented policies and procedures.
  • The Community Anticoagulation Therapy Clinic (CAT Clinic) currently has over 70 documented policies and procedures.


  • PCI found that each department had a different registration process, this was revised so same process used for all departments, when they went to electronic medical record (EMR) all departments had same process, saved time and resources.

Slide 13

A document image of a page entitled "Patient Flow in Anticoagulation Clinic."

  • In red text:
    • Note the:
      • Format and color—with an arrow pointing to the first rectangular box.
      • Document number—with an arrow pointing to the number box.
      • Purpose—with an arrow pointing to the purpose box.
      • Definition—with an arrow pointing to the definitions and acronyms box.
      • Procedure or flowchart—with an arrow pointing to both the procedure and flowchart.

Slide 14

The document image shows the continuation of the "Patient Flow in Anticoagulation Clinic."

  • The document shows the end of the flowchart, Records, and Revision History

Slide 15

The document image shows a page entitled "Master List."

  • Document shows document title:
    • Administration
    • Accounting
    • Human Resources
    • Quality Improvement
    • Quality System
  • Numbers
  • Approval date
  • Revision
  • Example entry under Human Resources:
    —Job Description Process: 2001 CATC - 12/16/05 -0

Slide 16

Flow of current clinic processes

  • Completed a process flow of current (2005) anticoag clinic processes
  • Lots of variation—several nurses providing information about dose changes to patients
  • Little use of evidence-based guidelines
  • Waiting for lab results
  • Pt. satisfaction low
  • Pt. education 15 minutes

Slide 17

Community Anticoagulation Therapy (CAT) Clinic

  • Provide patient education 60-90 minutes and ongoing
  • Patients go to lab of their choice, point of contact (POC) testing, home INR monitor
  • INRs faxed to CAT Clinic or provided via Web
  • Pt. notified of results same day and dosing decision made based on guidelines
  • Referring physician notified of all results and changes in warfarin therapy

Slide 18

ACCP Guidelines

  • Why use guidelines to manage anticoagulation?
    • To reduce gaps in knowledge
    • To reduce safety issues surrounding anticoagulation
    • Both of the above promote standardization in the practice of managing patients taking warfarin


  • No different than management of CHF, diabetes, hypertension (HTN), myocardial infarction (MI)

Slide 19


  • Maintenance Therapy
  • Make small changes to warfarin—increase or decrease dose 5-15%, if INR between 1.0 and 5.0
  • Calculate the weekly dose and adjust according to the total weekly dose. If patient taking 5mg/day=35mg/week. If dose increased or decreased by 10% = 3.5mg/week
  • Check INR every 4 weeks at a minimum
  • Give the warfarin time to work—may take 48 hours to see a change in INR

Slide 20

What affects how warfarin works?

  • Other medications—antibiotics, herbs, aspirin products, chemotherapy, nonsteroidal antiinflammatory drugs (NSAIDs), amiodarone (decrease warfarin by as much as 30%)
  • Diet—amount of vitamin K in foods
  • Alcohol—warfarin is synthesized in the liver
  • Exercise
  • Stress


  • Antibiotics can increase or decrease INRs so watch closely. Do not arbitrarily decrease or increase dose of warfarin while pt. is taking an antibiotic. Check INR 3-4 days after antibiotic started (if one that affects INR) and then 3-4 days after pt. stops antibiotic. Most common culprits, levaquin, flagyl, Cipro
  • Aspirin (ASA) and NSAIDs inhibit platelet aggregation so can increase bleeding, NSAIDs can increase gastric irritation and increase risk of bleeding
  • Dietary Supplements like Ensure, Slim Fast may have high amounts of vitamin K

Slide 21

What does all of this mean?

  • Each time the patient has an INR (especially if elevated or low), ask about changes in medication, OTCs, alcohol, diet, stress, missed/extra doses.
  • Each face-to-face or telephone visit is a great opportunity to reinforce (anticipatory guidance).
  • If dose is changed, ask pt. to repeat instructions; clarify dose vs. pill size (5mg = 1 pill).


  • Brand name Coumadin and generic warfarin pills are different colors for different mg sizes. Doesn't matter if brand or generic colors will be the same for the same mg. For instance 2.5mg size is green for brand and for generic.

Slide 22

What does all of this mean?

  • It takes time to educate—more than a 10 or 15 minute office visit


  • Binge drinking typically causes elevation in INR.
  • Chronic drinking typically causes decrease in INR so increased doses of warfarin needed.
  • Alcohol consumption is a safety issue—falls.

Slide 23

Education and Communication

  • Educate, Educate, Educate
  • Health Literacy—50% of adult population reads below 8th grade level
  • Joint Commission National Patient Safety Goal #13—Encourage patients' active involvement in their own care as a patient safety strategy.
  • Find patient friendly materials such as "Your Guide to Coumadin®/Warfarin Therapy" at
  • Teach back—ask; "Just so I know I explained things correctly, can you tell me 3 signs of bleeding that you need to report to your Dr."


  • Ask simple assessment questions like do you like to ready, are you happy with the way you read, how far did you go in school. This may lead to more conversation about how well they read.
  • How would you explain A Fib to a patient?

Slide 24

The photograph shows the front cover of AHRQ's, Your Guide to Coumadin/Warfarin Therapy.

Slide 25

Medical Record

  • CAT Clinic utilizes a Web-based electronic medical record
  • Automatic list of patients due for INRs
  • Warfarin log—easy to read
  • Control Chart
  • Next apt. date
  • Sent to referring physician
  • Reports at the click of a button


  • How do you know how well your patients are doing with their INR range? How many dose changes? Are any patients overdue for lab tests? How many times have patients been hospitalized or visited the ER for bleeding or clotting problems?

Slide 26

A handwritten record of a patient's history including:

  • Testing site
  • Patient's name
  • Phone number
  • Physician's name
  • Diagnosis
  • Tablet size
  • Date
  • Return Appointment
  • PT/Ratio/INR
  • Physician orders
  • Notified Pt initials

Slide 27

The document image shows a Cedar Rapids Healthcare Alliance's, Community Anticoagulation Therapy (CAT) Clinic Patient INR History page which includes:

  • Date
  • Prior/Scheduled Visit
  • Flag
  • Warfarin
  • Notes from Pt.

Slide 28

The line graph presents the INR results for a specific patient [451.19 Deep Vein Thrombosis, DVT]. The vertical axis goes from 0.00 to 6.64 and the horizontal axis shows the visit dates of 1/20/2005 to 8/24/2008. The line graph starts at 1.66 and goes up and down reaching a maximum of 6.64 on 5/10/2005, a low of under 1.66 on 9/19/2005, and finishing around 2.49 on 8/24/2006.

The coloring of the graph is noted in a rectangular box:

  • Green area denotes recommended patient INR range [2-3]
  • Yellow area denotes readings that are outside of INR range, but within individuals' typical INR range of readings
  • Red area denotes readings that are outside of individuals' typical INR range of readings

Another rectangular box reads:

  • Average INR (calculated)=2.45
  • Std Dev INR=1.23
  • Upper Control Limit (UCL)*=6.14
  • Lower Control Limit (LCL)*=0
  • *based on 3 standard deviations
  • Percent Within Range (Green Area)=25.81% [8/31]
  • Percent Above Range (Yellow and Red Area)=25.81%
  • Percent Below Range (Yellow and Red Area)=48.39%

Total Dosage Amount per week (last change)=85 mg

Dosage Change History Table reads:

  • 5/31/2006 [delete]: Sun-10; Mon-15; Tue-10; Wed-15; Thu-10; Fri-15; Sat-10; Total-85
  • 2/21/2006 [delete]: Sun-10; Mon-10; Tue-10; Wed-10; Thu-10; Fri-10; Sat-10; Total-70
  • 1/19/2006 [delete]: Sun-15; Mon-15; Tue-15; Wed-15; Thu-15; Fri-15; Sat-15; Total-105
  • 12/21/2005 [delete]: Sun-10; Mon-10; Tue-10; Wed-10; Thu-10; Fri-10; Sat-10; Total-70
  • 10/12/2005 [delete]: Sun-10; Mon-15; Tue-10; Wed-0; Thu-10; Fri-15; Sat-10; Total-70

Slide 29

The bar graph presents the percent of total inpatient ADEs related to warfarin at St. Luke's. The vertical axis goes from 0.0% to 25.0% and the horizontal axis shows the years of 2002 to 2007.

The data shows:

  • In 2002: 25.1% of total inpatient ADEs related to warfarin
  • In 2003: 24.8% of total inpatient ADEs related to warfarin
  • In 2004: 21.2% of total inpatient ADEs related to warfarin
  • In 2005: 10.8% of total inpatient ADEs related to warfarin
  • In 2006: 12.5% of total inpatient ADEs related to warfarin
  • In 2007: 5.3% of total inpatient ADEs related to warfarin


  • Bleeding and clotting events, INRs>5
  • Code E934.2 and 709.92

Slide 30

A screen shot of medical software for "Preferred Methods for Calculating Therapeutic Time in Range."

Slide 31

The line graph presents the Percent of Time Patients in INR Range: Rosendaal. The vertical axis goes from 0 to 100 and the horizontal axis shows the dates of Jun-06 through Jun-08. The line graph for CAT Patients starts at 65 in Jun-06, reaches a maximum of 69 in Sep-06, a low of 49 in May-07, and ends at 65 in Jun-08. The line graph for Prior Visits starts at 61 in Jun-06, reaches a maximum of 65 in Jul-06, a low of 41 in Nov-06, and ends at 45 in Mar 07. The Benchmark line runs at 65 from Jun-06 through Jun-08.

  • Median percent of Time in INR Range (CAT Clinic) =59%
  • Note: Benchmark—JCAHO, Journal of Quality and Safety, Vol. 29 (12), 2003 and AC Forum 2007.

Slide 32

The line graph presents the Percent of Time Patients in INR Range +/- 0.2. The vertical axis goes from 0.0 to 100.0 and the horizontal line shows the dates from Aug-06 to Jun-08. The line graph for CAT Patients starts at 74 in Aug-06, has maximums of 81 in Jan-08, May-08, and Jun-08, a low of 54 in Mar-07 and ends at 81 in Jun-08. The line graph for Prior Visits starts at 69 in Aug-06, reaches a maximum of 72 in Sep-06, a low of 50 in May-07, and ends at 58 in Sep-07.

  • CAT Clinic patients in tighter range


  • Tighter should mean less clotting and bleeding events
  • Less INR, decreased cost

Slide 33

The line graph presents Physician Contacts. The vertical axis goes from 0% to 30% and the horizontal axis shows the dates of Apr-06 through Jun-08. The line graph starts at 5% in Apr-06, reaches a maximum of 22% in Jul-06, lows of 1% in Dec-07, Feb-08, and Apr-08, and ends at 3% in Jun-08. The Median runs at 4% from Apr-06 to Jun-08.

  • This graph shows a decrease in the number of physician contacts (the number of times the CAT Clinic nurse needs to contact the referring physician). This number should decrease as patients are in INR range a greater percent of the time.

Slide 34

The line graph presents the Percentage of INRs Greater Than 5. The vertical axis goes from 0.00% to 3.50% and the horizontal axis shows the time period of 3rd Q 2006 through 2nd Q 2008. The line graph starts at 1.00% in 3rd Q 2006, reaches a maximum of 3.2% in 4th Q 2006, lows of .50% in 1st Q 2007 and 2nd Q 2007, and ends at 1.4% in 2nd Q 2008.

  • The graph shows the percent of INRs greater than 5. There have been two associated major bleeds in 2007 (GI bleeding, requiring hospitalizations, one pt. taking NSAID, another pt. taking ASA and started on Amiodarone) with the INRs greater than 5.
  • Note: Benchmark 7%, Chiquette, Amato, Bussey, 1999.

Slide 35

The sample document presents the "Warfarin Compliance Assessment Scale #6515CATC" which shows the points and patient score for the following:

  • Missed doses-not prescribed
  • Additional doses-not prescribed
  • Diet: how has your diet changed over the past week?
  • Alcohol consumption
  • Medications
  • Total score

Slide 36

The line graph shows the Average Compliance Score. The vertical axis goes from 80 to 100 and the horizontal axis shows the dates from May-06 to Jun-08. The line graph for Ave Compliance Percentage starts at 98.5 in May-06, reaches a maximum of 99.9 in Oct-07, a low of 98 in Jun-06, and ends at 99.5 in Jun-08. The Average runs at 99 from May-06 through Jun-08.


  • Compliance score includes: missed/extra doses, less/more vit K, more ETOH intake, addition of antibiotic, NSAID, herbal supplements or amiodarone

Slide 37

Toolkit Items

  • ISO Executive and Staff Training Modules
  • INRPro Database—
  • Organized Document System—70 documents
  • Compliance Assessment Scale
  • Patient Education—Your Guide to Coumadin®/Warfarin Therapy
  • Staff Education Modules

Slide 38


  • Identify the challenges and barriers to implementing medication safety tools.
  • Explain the importance of utilizing evidence-base guidelines for managing warfarin therapy.
  • Explain the importance of education for patients taking warfarin.
  • List the advantages of dedicated anticoagulation clinics.

Slide 39


  • Cedar Rapids Healthcare Alliance
  • Most recent anticoagulation management guidelines
  • My Guide to Warfarin Therapy:
  • Your Guide to Coumadin®/Warfarin Therapy:>

Slide 40

Carla S. Huber, ARNP MS
CAT Clinic
600 7th Street SE
Cedar Rapids, IA 52401

Current as of February 2009
Internet Citation: Medication Safety: Anticoagulation Management (Text Version). February 2009. Agency for Healthcare Research and Quality, Rockville, MD.


The information on this page is archived and provided for reference purposes only.


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