Thursday, November 29, 2007

Best Practices For Nurses: Caring and Educating the DVT Patient on Anticoagulation Therapy - Final Draft

“Each year, venous thromboembolism affects about 1 in 1,000 people in the United States” (Bartley, 2006). Typically a venous thromboembolism begins as deep vein thrombosis.
The clot may break loose, travel to the lungs, resulting in a pulmonary embolism, a serious and most times deadly condition. Warfarin has become the drug of choice in treating and preventing deep vein thrombosis and other conditions. Adverse reactions such as skin necrosis and risk factors such as cerebral hemorrhage can be severe; nurses must educate patients regarding the importance of careful monitoring and compliance with anticoagulation therapy.
Deep vein thrombosis (DVT) mostly involves the legs. Certain health conditions such as heart failure, prolonged bed rest and immobility are increased risk factors for developing DVT’s. All patients are different and may not show the same, or any, signs and symptoms. Classic symptoms are acute swelling, redness and warmth in the affected limb. The patient may or may not have pain with Homan’s sign – calf pain when the foot is dorsiflexed. Bartley reports studies have shown a 10% to 40% incidence of hospital-aquired DVT among medical and general surgical patients who do not receive prophylaxis, for patients who undergo major orthopedic surgery, it’s 40 to 60% (2006).
There are interventions to help prevent and manage DVT’s. To better help circulation and reduce risk of blood clots, nurses can make mechanical prophylaxis a part of their care plan. Mechanical prophylaxis includes compression stockings and intermittent pneumatic compression devices and venous pump. For management of DVT’s, the use of anticoagulants includes warfarin and heparin. Warfarin, also known as coumadin, inhibits the synthesis of coagulation factors dependent on vitamin K, which are factors II, VII, IX and X. It also inhibits proteins C and S anticoagulants. Warfarin absorbs rapidly from the GI tract, peaking absorption 60 to 90 minutes after ingestion. The anticoagulation effects of warfarin typically take 3 to 4 days after administration and last 4 to 5 days. Turner states warfarin is 99% plasma protein bound, mainly to albumin. It accumulates in the liver until it is broken down into inactive metabolites and excreted in urine (2006). For a patient with impaired renal function, the dosage of warfarin does not need to be adjusted. Conditions such as cirrhosis or congestive heart failure increases warfarin's anticoagulant effects and decreases its metabolism. Vitamin K reverses anticoagulant effects of warfarin.
In addition to the nurse understanding how warfarin works in the body, the patient needs an understanding of the therapeutic effects of the medication. Nurses accomplish this by monitoring the Prothrombin time and the International normalized ratio (PT/INR) in collaboration with the physician and pharmacist. Prothrombin time uses a reagent called thromboplastin, a substance sensitive to levels of Vitamin K dependent factors. These are factors II, VII and X. Unfortunately, the reagents vary from lot to lot, making the PT values vary in labs worldwide. “To ensure consistency and reliability in reporting PT, the World Health Organization introduced a system known as International Normalized Ratio (INR)” (Gibbar-Clements, 2000). INR takes thromboplastin sensitivity into account, therefore should be used along with PT. Average starting dosages of warfarin are 2 to 5 mg a day. Doses thereafter are adjusted according to the PT/INR results. Daily monitoring is needed until a target therapeutic range is reached for 2 consecutive days. The goal of warfarin therapy is a PT of 1.5 to 2.5 times the control value or an INR of 2.0 to 3.5. There are various INR ranges for various health conditions. The target INR range for DVT’s and pulmonary embolism is 2.0 to 3.0. Turner recommends The American College of Chest Physicians' guidelines in dealing
with elevated INR without active bleeding:
If the INR is above the therapeutic range but below 5, the patient may skip the next dose and the warfarin dosage may be reduced. If the INR is 5 or greater but less than 9, the patient should skip the next one or two doses and restart warfarin at a lower dose, as prescribed, once the INR has stabilized in the therapeutic range. The prescriber also may order oral vitamin K, the antagonist to warfarin in low doses (5mg or less). If the INR is 9 or above, administer higher-dose oral vitamin K (5 to 10 Mg) and discontinue warfarin until the INR stabilizes in the therapeutic range. Once the INR is therapeutic, warfarin can be resumed at a lower dose. (2006, p.44)
Low INR is equally dangerous for the potentiate of blood clotting. While on warfarin, blood testing is indefinite. Once stabilized, testing typically is done weekly from 4 to 6 weeks, then monthly.
Nurses have a large role in monitoring warfarin's therapeutic and side effects, as well as educating patients. One of the most important side effects to monitor for is bleeding. “Teach patients to monitor closely for signs and symptoms of bleeding gums, bruises, nosebleeds, blood in vomit, bloody stools, dark tarry stools, blood in the urine, tea-colored urine, difficulty in controlling bleeding from small cuts and heavy menstruation” (Malacaria and Feloney 2003). If bleeding is noted, hold the next dose of warfarin until the healthcare provider has been notified. If symptoms of shortness of breath, dizziness, weakness and headache presents, internal bleeding may be happening and 911 should be called immediately. Use safe precautions to minimize bleeding such as soft-bristle toothbrushes and electric razors. A patient should discuss the use of
any over-the-counter medications, such as cold medications and herbal supplements, with their provider while on warfarin therapy. Inform patients to wear some type of identification stating he or she is on anticoagulant therapy. Holcomb advises nurses to make sure the patient knows to maintain a consistent intake of vitamin K foods so they do not interfere with the warfarin (2006). Avoid excessive alcohol intake for it can shorten bleeding time. Patients must understand why they are taking warfarin and the importance of monitoring. Warfarin should be administered at the same time every day. If a dose is missed, take as soon remembered; do not take a double dose. Inform the patient that a sometimes rare but serious adverse reaction of warfarin is skin necrosis of the breast, butt, thigh or penis. This reaction usually occurs between day 3 and 8 of therapy. If this develops, warfarin is stopped. The patient will be re-started on IV heparin, followed by a lower dose of warfarin. Other mild adverse reactions that may occur are headache, nausea, diarrhea, GI cramps, rash and hair loss.
Warfarin can be life-saving for many patients with DVT. By educating patients how warfarin works, the importance of monitoring by checking PT/INR and crucial side effects, the patient will benefit from warfarin therapy with decreased risks.




Barriers for the Nurse Caring and Educating the DVT patient on Anticoagulation Therapy

Intervention 1: T he patient needs an understanding of the therapeutic effects for patient compliance and safety. It is especially important once the patient is on an outpatient status.
i.One disadvantage/barrier for the patient is ethnicity/racial background.
A study was done using residents from New Jersey's medicaid or pharmacy assistance for the aged and disabled program, assessing how frequently these patients filled their prescriptions for 3 months of oral anticoagulant therapy and what demographic and clinical factors predicted a less adequate duration of care. “The most recent evidence-based recommendations of the American College of Chest Physicians (ACCP) call for at least 3 months of oral anticoagulant therapy after PE or DVT unless therapy is contraindicated” (Ganz, et al). The study found that of the 437 caucasian particants, 20% had an inadequate duration of therapy. Out of 105 african americans tested, 30% had an inadequate duration of therapy:
Our finding of an asociation between race and inadequate duration of therapy is consistent with prior studies showing undertreatment of African Americans for ischemic heart disease, glaucoma, and other conditions. This association is unlikely to be confounded by income, because enrollment in medicaid did not emerge as an important determinant of short duration of therapy in either univariate or multivariete analyses. A recent study using data on medicare beneficiaries has shown that race remains a persistent determinant of disparities
in the use of a variety of health services, even after adjusting for income.(Ganz, et al, pg 779)
ii.Another disadvantage is knowledge deficit.
“There is evidence that adherence to medical treatment is enhanced by knowledge and understanding of the drug, its benefits and its side-effects” (Nadar, et al). Nurses must pull together all resources to make sure their patients have a clear understanding of why they are taking an anticoagulant. A study published in the Journal of the Royal Society of Medicine tested 180 patients. 135 were white European, 29 were Indo-Asian and 16 were Afro-Caribbean. 45% of the Indo-asian patients, compared with 18% of the Europeans and 19% of Afro-Caribbeans felt they had difficulty understanding their anticoagulant management. 94% of patients knew what type of drug warfarin is but only 54% knew why they were taking it and what dose they were on. “Another reason for the patients' lack of knowledge concerning the disease process and the side-effects could of course , be poor conselling and information-giving by healthcare professionals” (Nadar, et al). As regards written material, (Estrada et al) found that some of the patient information on anticoagulation therapy was above the comprehension level of most patients. This study concluded that many of the patients did not know why they were attending anticoagulation clinic, why they were using anticoagulants, and a poor idea of complications. This can compromise patient safety if they do not fully understand the importance of taking anticoagulant medication and importance of PT/INR monitoring.
Intervention 2: Educating patients of important side effects.
i.A disadvantage is language barriers
Nurses must make sure their patients have a better understanding of side effects by having the patient repeat what they were taught. Also patients that have english as a second language may understand better with literature written in their native language, as well as using an interpreter while educating to make everything more clear to the patient. 49% of the Indo-asian patients attended the clinic with them because “to help them out with language problems” (Nadar, et al). In the study done in the UK when asked about potential side effects, most could mention only one, which was increase in bleeding. All of the participants knew what could happen if they were to stop taking warfarin.
ii.Another disadvantage is ethnicity.
Some patients of different ethnic backgrounds are more comfortable with a provider of the same ethnicity, especially in the older adult populations. “62% of the Indo-Asians preferred to have a doctor of the same ethnic origin” (Nadar, et al). Nadar, et al study also confirmed that many Indo-Asian patients felt more comfortable with a doctor of the same ethnic group , possibly for language reasons but perhaps also because they would feel more at ease in asking questions.

References

Bartley, M. (2006). Keep venous thromboembolism at bay. Nursing 36, 36-41.
Gibbar-Clements, T., Shirrell, D., Bogley, R., and Smiley, B. (2006). The challenge of warfarin therapy. American Journal of Nursing, 100, 38-40.
Holcomb, S. (2006). Coumadin (warfarin) therapy. Nursing, 36, 45-46.
Malacaria, B., and Feloney, C. (2003). Going with the flow of anticoagulant therapy.
Nursing, 33, 36-. Retrieved January 25, 2007 from TCC Proquest database.
Turner, L. (2006). Keeping warfarin therapy in balance. Nursing, 36, 43-44.
Nadar, S. et al (2003). Patients' understanding of anticoagulant therapy in a multiethnic population. Journal of The Royal Society of Medicine, 96: 175-179.
Ganz, D. A., et al (2000). Adherence to Guidelines for Oral Anticoagulation after Venous Thrombosis and Pulmonary Embolism. Journal of General Internal Medicine, 15:776-781
Estrada, et al, (2000). Anticoagulant patient information material is written at high readability levels. Stroke, 21:2966-70.

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