Blood Thinners. What, When, Why, How. Mary Wilkie, MS, RN, CCNS Clinical Nurse Specialist Rush University Medical Center

Transcription

1 Blood Thinners What, When, Why, How Mary Wilkie, MS, RN, CCNS Clinical Nurse Specialist Rush University Medical Center

2 Objectives Discuss specific defects and/or disease processes in ACHD that require blood thinners Review the most common blood thinners that are available today

3 What Are Blood Thinners? Medications that help prevent clots from forming in the blood

4 Most Common Types of Blood Thinners Anticoagulants Increase the time it takes for blood to form a clot Antiplatelets Prevent platelets from sticking together and forming a clot Heparin Dalteparin (Fragmin) Enoxaparin (Lovenox) Warfarin (Coumadin or Jantoven) Dabigatran (Pradaxa) Rivaroxaban (Xarelto) Apixaban (Eliquis) Aspirin Clopidogrel (Plavix)

5 Terms to Know Thrombus - clot Thrombosus - formation of blood clots Thromboembolism - a clot (thrombus) that breaks loose and is carried by the bloodstream resulting in an obstruction of another vessel including the lungs, brain, kidneys, GI tract, leg

6 Clotting Bleeding

7 Blood Thinners in Adult Congenital Heart Disease Mechanical/bioprosthetic valve Atrial arrhythmias Fontan Circuit Transcatheter closure devices, stents, valves Cardiomyopathy/myocarditis Pulmonary Hypertension

8 Anticoagulation in the Fontan Circuit Early and late risk for thromboembolic event Increased risk factors: type of Fontan, enlarged atria, arrhythmias, decreased heart function, fenestration, PLE, liver congestion Evaluate individual risk factors Aspirin vs. Warfarin vs. combination INR goal 2-3 (varies by center) Single ventricle patients may be predisposed to both bleeding and clotting Risk factors may change over time! Important to do regular follow-up with echocardiogram

9 Prosthetic Valves Goal Mimic one s own native valve Mechanical Titanium, Teflon Very durable Require surgery Require life long anticoagulation Bioprosthetic Pigs heart valve or cows heart tissue Not as durable (most durable on the r side) Transcatheter bioprosthetic valves available Do not require lifelong anticoagulation Clotting Risk Higher in Mitral than Aortic valve position Risk increases with presence of atrial fibrillation, LV dysfunction, left atrial dilation, previous thromboembolism, other conditions that cause blood to clot

10 Anticoagulation for Prosthetic Heart Valves 2013 Prevention and Treatment of Thrombosis In Pediatric and Congenital Heart Disease: A Scientific Statement from the American Heart Association 2014 AHA/ACC Guidelines For The Management of Patients with Valvular Heart Disease

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12 Right Heart Valve Replacement Bioprosthetic Pulmonary Valve - reasonable to forgo anticoagulation. Consider individual clotting risks Bioprosthetic Tricuspid Valve months of Warfarin with INR goal of lifelong low dose Aspirin. Again, consider individual risks Right sided mechanical valves Lack of data Warfarin Goal /- Aspirin Prevention and Treatment of Thrombosis In Pediatric and Congenital Heart Disease: A Scientific Statement from the American Heart Association. Circulation. 2013:128:

13 Anticoagulation Use for Atrial Arrhythmias Many ACH patients at risk for A-fib or A-flutter Fontan, TGA s/p Mustard or Senne procedure, s/p TOF, unrepaired ASD Important to evaluate individual s risk for clots Low risk patients - Aspirin High risk strongly consider Warfarin INR target range 2-3, except with a mechanical valve or recurrent thrombosis; then plus low dose ASA may be added May consider new anticoagulation agents in non-valvular a- fib

14 Thrombus Prevention Following Interventional Procedures Limited studies, mostly based on medical consensus ASD, VSD, PFO closure device, stents, percutaneous valves - Aspirin plus Clopidogrel (Plavix) for the first 6 months Consider Warfarin in patients with atrial arrhythmias (Afib), blood clotting disorder or previous stroke Nonsurgical Ablation procedure low dose Aspirin for 4-6 weeks following procedure

15 Use of Blood Thinners in Dilated Cardiomyopathy At risk for thrombus formation secondary to low cardiac output, decreased cardiac function, regional wall motion abnormalities, arrhythmias Limited recommendations as it relates to ACHD Ongoing therapy reasonable for those with arrhythmias, hx thrombosus/thromboembolism, SF 10% or EF < 25% Adult review suggests benefit in those with SF < 20%, LV dysfunction, hx of previous stroke, previous thrombus, arrhythmias Warfarin with/without Aspirin INR range 2-3

16 Anticoagulation in CHD Patients with Pulmonary Hypertension The use of anticoagulation may be reasonable in children and adults with pulmonary vascular obstruction disease associated with CHD Clinical judgment Requires further investigation

17 Special Circumstances to Consider Immobilization while traveling Obesity Oral contraceptives Pregnancy Other medical conditions e.g., Protein S or C abnormalities, chromosomal abnormalities

18 Warfarin Brand name Coumadin Decreases the body s ability to form clots by blocking Vitamin K dependent clotting factors

19 Warfarin Color Coded Tablets Convenient for titrating dose Possible safety risk

20 Warfarin Challenges Slow onset and offset of action Effect can be different person to person Narrow therapeutic index Many food and drug interactions

21 Contraindications to Warfarin Use Bleeding Pregnancy Allergy or intolerance to Warfarin Uncontrolled HTN* Liver disease* Recent surgery and procedures involving the nervous system, spine, eye* *Use with extreme caution

22 Complications of Warfarin Bleeding Warfarin Embryopathy 5-30% Osteoporosis 0.1 % Warfarin necrosis 0.02% Purple toe syndrome 0.01%

23 Signs of Bleeding Excessive bleeding of the gums or nose New /Significant Headaches Abdominal pain or cramping Vomiting blood or something that looks like coffee grounds Pink or brown colored urine Red or tarry black stool Heavier than usual menstrual flow Excessive bruising or bruises that get larger Cuts that won't stop bleeding after applying continuous pressure

24 Drug Interactions Increase Effect Antiarrhythmics Antibiotics Anticonvulsants Antidepressants Antifungals Antihyperlipidemics Anticoagulants Decrease Effect Antibiotics - Rifampin Antidepressants - SSRI, SNRI Antiepileptics - Phynetoin (Dilantin) - Phenobarbital - Carbamazepine (Tegretol) Always Notify Your Health Care Provider Before Starting or Stopping Medication

25 Warfarin is Affected by Foods that Contain Vitamin K Green, leafy vegetables including spinach, kale, lettuce, broccoli, cabbage, Brussels sprouts Avocado Soybean and Canola oil Mayonnaise and salad dressings Green tea Liver and organ meats Alcoholic beverages, cranberry and grapefruit juices all serve to increase the effect of Warfarin

26 Keep Your Diet Consistent!!

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29 Activity While on Warfarin Keep exercise level regular Avoid contact sports and activities that could result in a serious blow to head, chest or abdomen and/or serious cuts or bleeding Wear a helmet when riding moving objects Caution with sharp objects

30 Considerations When Taking Warfarin Take medication at the some time each day Never take a pill to catch-up if you miss a dose Be aware of drug interactions including prescription meds, OTC meds, vitamins, herbal supplements, nutritional supplements Inform all healthcare providers that you have been prescribed Warfarin (includes dentist, chiropractor, alternative medicine doctor), especially when planning any procedure or surgery

31 Considerations When Taking Warfarin (con t.) Try to avoid medications that can cause bleeding: Aspirin, Ibuprofen, Aleve, Naproxen Read all med labels to be certain that they do not contain Aspirin Tylenol is usually OK, but check with MD first Make your doctor aware of any missed doses Generic vs. name brand Wear medical alert bracelet/tag

32 Renal Impairment in Warfarin Dose adjustments are generally not necessary Patients with renal impairment may have platelet defects causing increased risk of bleeding Use Caution!

33 Warfarin In Pregnancy/Breastfeeding Crosses the Placenta Animals and Human studies have demonstrated positive evidence of fetal abnormalities. Must carefully weigh risk/benefit American Academy of Pediatrics considers Warfarin as compatible with the practice of breast-feeding

34 INR Testing Guidelines INR (international normalized ratio) The INR is a standardized way to report the PT value which is the time in seconds that is needed for blood to clot The normal INR of a healthy person is 1 The higher the INR, the more risk you have of bleeding If INR is lower than the desired target, the more risk you have of clotting.

35 INR Testing Guidelines (con t.) Ideal target INR will vary depending on the medical condition and individual risk factors Most common INR range is 2-4 Common factors affecting INR - Drugs - Diet - Exercise - Alcohol use - Illness

36 Laboratory testing - Venous blood draw - Accurate INR Testing - Requires trip to clinic, hospital Point of Care(POC) Devices - Finger stick - Easy, accurate, convenient - Becoming more accepted by insurance companies

37 Low Molecular Weight Heparin (LMWH) Anticoagulant that inhibits the body s natural clotting factors Enoxaparin (Lovenox), Dalteparin (Fragmin) Inject SQ (under the skin) One or two time a day dosing No need for lab monitoring in most patients. May monitor anti X-a level. Good for long term and home use, safe during pregnancy, presumed safe with breastfeeding Often used as bridging medication Black box warning for spinal/epidermal hematomas Caution in renal and liver disease

38 Low Molecular Weight Heparin (LMWH) (con t.) Potential side effects: bleeding, nausea/vomiting Contraindications: active bleeding, low platelet count, hypersensitivity to heparin, pork, or benzyl alcohol Limited studies in use with mechanical valves Pregnant women may need closer monitoring and dose adjustment Timing of anti X-a - usually drawn 4 hours after administration of dose

39 Aspirin Antiplatelet Fewer bleeding complications that with Warfarin but may not prevent clotting in certain conditions 81 mg vs. 325 mg daily Doesn t require regular blood testing May need to be held 5-7 days before surgery or invasive procedure Common side effects: bleeding, heartburn, nausea, ulcer Caution in patients with history of GI bleed, renal or liver disease Use during pregnancy and during breastfeeding requires close monitoring

40 Clopidogrel (Plavix) Antiplatelet - affects platelet function and bleeding time for up to 7-10 days (recommend discontinuing 5 days prior to surgery) Usual dose 75 mg once a day Does not require regular blood testing Side effects: bleeding, TTP, rash, diarrhea Drug interactions: avoid concomitant use of PPI ( ex: Prilosec, Nexium), caution with SSRI, SNRI drugs Grapefruit /Plavix interaction?

41 Plavix Information on safety in pregnancy and breastfeeding has not been fully established Class B Pregnancy - animal data negative, no controlled human data Animal data did show excretion of drug into breast milk. No controlled human studies

42 Advantages of New Anticoagulants Rapid onset of action No need for bridging More predictable effect No need for routine coagulation monitoring Low potential for food/drug interactions No dietary restrictions

43 Dabigatran (Pradaxa) Use: Non-valvular Atrial Fibrillation No frequent blood testing needed Available in 75 mg and 150 mg capsules No antidote Side effects: Bleeding, GI upset,? increase risk for heart attack Less drug interactions - Caution with Rifampin, St. John s Wort, Tegretol, Phenytoin, Varapamil, Amiodarone, Zitromax, other drugs that cause bleeding No food-drug interactions

44 Dabigatran (Pradaxa) (con t.) Contraindications - Active bleeding - Renal impairment - Liver disease - Prosthetic heart valves - Valvular heart disease - Immunosupressants, Ketoconazole Unstable if not stored in original bottle or blister pack - NO pill boxes Must be used within 60 days while being stored in original bottle or blister pack Cost FDA statements

45 Rivaroxaban (Xarelto) Indication: Non-valvular Atrial Fibrillation, DVT, PE Not for use in prosthetic heart valves or mitral stenosis Once daily dosing - 20 mg No antidote Lab monitoring: Not needed. Drug interactions - Ketoconazole, Ritonavir, Clarithromycin, Erythromycin - Rifampicin Minimal food interactions-recommend to be taken with food No controlled studies in pregnant women

46 Apixaban (Eliquis) Indication: Nonvalvular Atrial Fibrillation, DVT No need for monitoring Recommend 5 mg twice daily dosing No established reversal/antidote Cut dose for kidney function, age > 80; wt < 60 kg Drug Interactions: Certain drugs may increase or decrease effect Ex: potency with Ketoconazole, Clarithromycin, potency with Rifampin, St. John s Wort, Phenytoin Not recommended for mechanical valves No adequate studies in pregnant women Hold at least 48 hours prior to high risk surgery/procedure and at least 24 hours before low risk procedure Bridging generally not requires Always Check with Your Healthcare Provider!

47 Become Educated Follow Directions Carefully Communicate

48 Thank You For Your Time!