Coumadin/WarfarinMinimizing risk
and
Optimizing Safety
National Patient Safety Goal 3JCAHO
Anticoagulation therapy poses risks to patients and often leads to adverse drug events due to complex dosing, requisite follow-up monitoring, and inconsistent [patient] compliance. The use of standardized practices for anticoagulation therapy that include [patient] involvement can reduce the risk of adverse drug events associated with the use of heparin (unfractionated), low molecular weight heparin, and warfarin.
The incidence of major bleeding for patients on Coumadinis 20%
Elements of Performance
• The hospital uses approved protocols for the initiation and maintenance of anticoagulant therapy appropriate to the medication used, to the condition being treated, and to the potential for medication interactions.
• For patients starting on warfarin, a baseline International Normalized Ratio (INR) is available, and for all patients receiving warfarin therapy, a current INR is available and is used to monitor and adjust this therapy.
• The hospital provides education regarding anticoagulant therapy to prescribers, staff, patients, and families.
Why do we need a protocol?
83 y o F presents to the hospital with new onset atrial fibrillation. Her CHADS2 score is 4, so she is started on warfarin.
First MD orders warfarin 5 mg dailyNext MD orders warfarin 10 mg X 1, unaware of first orderPatient receives 15 mg PO warfarin on Day 1 without a baseline INR
INR on Day 2 is 1.2 and patient receives 5 mg warfarin
INR is not checked on Day 3 but patient continues to receive daily 5 mg dose of warfarin….
You can see where this is going!
Pharmokinetics
• Interferes with synthesis of Vitamin K -dependent clotting factors II, VII, IX and X
• Absorbed through GI tract• Activity: Peaks in 1.5 - 3 days
Duration 2- 5days• Half-life: 1-2.5 days• Metabolized in the liver• Excreted through urine and feces
Coumadin affectsthe intrinsiccoagulation
pathway preventingclotting
Coumadin Indications• Prophylaxis of venous thrombosis
(high risk surgery)• Treatment of venous thrombosis• Treatment of PE• Prevention of systemic embolism • AMI (to prevent systemic embolism) • Tissue heart valves• Atrial Fibrillation
Goal INR for these indications is 2-3 is recommended
Goal INR for these orthopedic patients is 2-2.5 is recommended
INR Values and DVTs
Contraindications
• Pregnancy
• Bleeding tendencies/blood dyscrasias
• Recent/contemplated surgery
• Threatened abortion
• Spinal puncture/Epidural
Lab Monitoring
• Regular monitoring INR• Repeat INR Daily until therapeutic
for 2 consecutive days then Q48hrs until discharge
• Goal INR 2-3 for protocol indications.• Other indications may have goal of
2.5 to 3.5• Standard dose time at MAH is 1800 to
allow lab results
WHERE CAN MY PATIENT GO TO GET THEIR INR DRAWN?
Dietary Considerations• Amount of vitamin K in foods affects therapy• Maintain a consistent amount of vit K in your diet• Avoid drastic changes in your dietary habits• Adding large amounts of these food items
will vitamin K in the body: – margarine, canola oil, olive oil, mayonnaise– broccoli, Brussels sprouts, kale, endives
cucumbers, – kiwi, blueberries– sauerkraut, soybeans, dill pickle– beef and pork liver– cashews
Other things that can affect Anticoagulation
Garlic
Ginkgo Biloba
Green tea
Alcohol: can affect liver function which is the site of warfarin/coumadin metabolism
Anticoagulation affect
Drug/Drug Interactions
Drugs that may INCREASE anticoagulant effect or risk of bleeding:
Amiodarone*** Cimetidine (Tagamet) Levothyroxine (Levoxyl) Stomach remedies (Prilosec) Laxatives (Sennakot) Phenytoin (Dilantin) Quinidine Quinine Pain relievers (Motrin)
**** Requires a 50% reduction in warfarin/coumadin if new to therapy
Anticoagulant effect
Drug/Drug Interactions
Anti-infectives: Fluconazole (Diflucan) Erythromycin Fluoroquinolones Metronidazole (Flagyl) TMP-SMX (Bactrim)
Anticoagulanteffect
Drug Interactions
May DECREASE anticoagulant effect: Barbiturates Carbamazepine (Tegretol) Cholestyramine (Questran) Rifampin Vitamin K
Anticoagulanteffect
Side effects: • Bleeding: Assess any of the following
symptoms as they may indicate internal bleeding or INR > 3:
– minor gums bleeding
– nosebleeds
– headache
– joint pain
– nausea/vomit
– melena
CPOE Order or Order SetIf you try to order Warfarin fora patient who has not had anorder for 30 days, you will geta prompt to ask you to consider discarding this orderand ordering the Warfarininitiating protocol
This is the Warfarin initiation protocol
Warfarin Protocolprovides decisionsupport
This is to be usedfor patients:
* new on Coumadin* for the indications listed * with goal INR of 2-3
Normogram indicates for eachday depending on what theINR is what the dose shouldbe or what the dose should becompared to the previousday’s dose
Prompts for baseline INRand daily INRs
Processing the Protocol Order
10/13/09
Coumadin perprotocol One time med sheet
18
Date Medication Time Date Date Date Date Date
IF CPOE Order: place paper order set in MD Order section of chart so MDs have the nomogram
MD will order subsequent orders as one time meds. Documentdose administration on One Time Medication Sheet and Coumadin Worksheet
To be placed in MedicationBooks and document doseadministered daily
Give to patient at discharge
Date Day of Time PT INR Dose RN signature of therapy
10/13
10/14
10/15
1
2
3
1800
1800
1800
1.2 5mg K Murphy RN
1.4 5mg D Morrison RN
2.3 2mg D Devanna RN
Warfarin Protocol Flowsheet
New Patient Education Brochure
New Brochure from theAgency for HealthcareResearch and Quality
Give to all patients on Coumadin
Anticoagulant Risk and Falls
Anticoagulants place a patient at additional RISK OF HARMTake note if patient is at RISK FOR FALL
FALL RISK + ANTICOAGULANTS =
POTENTIAL FOR LIFE THREATENING BLEEDING
Use Fall Mats if High Risk forfalls and onanticoagulants
Patient Teaching to prevent bleeding
Care when using sharp objects
– Use electric razor
– Use soft toothbrush
– Use waxed dental floss
– No toothpicks– Avoid bare feet
Patient Education
From the Caregroup Portal:Click on MicromedexClick on Carenotes systemType in CoumadinSelect tabletSelect English or SpanishPRINT
Provide patient withthis drug information
sheet as well
Case Study
Mr M is admitted to SDU with uncontrolled Atrial Fibrillation. He is initially started on Heparin drip and Metropolol for rate control. His heart rate is now controlled and is being transferred to South 4 to convert to Coumadin
The Coumadin Protocol is initiated
Baseline INR is 0.8
What is the dose this patient should receive on Day 1?
5 mg
Day 2The INR is 1.2 Your dose for the day should be?
5 mg
Day 3The INR is 1.4 Your dose for the day should be?
7.5mg
Day 4The INR is 2.2 Your dose for the day should be?
7.5mg
Day 5The INR is 3.1 your dose for the day should be?
6mg