Many patients in nursing facilities receive anticoagulation therapy to prevent blood clots, also known as thromboemboli. Deep venous thrombosis (DVT) and pulmonary embolism (PE) are dangerous yet common in elderly patients. Pulmonary embolism is caused when a blood clot travels to the lungs, causing acute shortness of breath. Death can occur within 30 minutes. DVT is harder to recognize, but can lead to PE or, if unrecognized, cause chronic venous stasis and venous ulcers. In the nursing facility, most patients are on oral warfarin (Coumadin) to prevent blood clots.

Indications for Anticoagulation

In a healthy person, blood coagulation prevents blood loss when vessels are ruptured. After a vessel begins to bleed, chemical processes lead to the formation of fibrin threads that trap blood cells and form a clot. In our subacute and long-term care patients, anticoagulants are used for both the treatment and prevention of cardiac disease, CVA and thromboembolism.¹Anticoagulation must be monitored regularly with blood tests because it carries a significant potential for harm. Subtherapeutic levels can increase the risk of thromboembolic complications while supratherapeutic levels can increase the risk of bleeding. The risk of blood clots after orthopedic surgery is high. After total hip replacement, the incidence of DVT without anticoagulation is close to 25 percent. When the surgeon repairs a hip fracture, the risk without anticoagulation is 50 percent.

Cardiac patients are often on anticoagulation, to prevent strokes as well as DVT and clots within the heart itself. About 15 percent of strokes occur in patients with atrial fibrillation, because the atria quiver instead of beating. Blood isn't pumped out completely so it may pool and clot. If a piece of clot travels to an artery in the brain, a stroke can result. Ann Tuzson, PT, PhD, a clinician at the University of Virginia Health Sciences Center in Charlottesville, states that therapists need to pay close attention to the INR.²INR stands for international normalized ratio, and is a standardized way of reporting the results of blood coagulation tests. INR values of healthy people who are not anticoagulated will be between 0.8 and 1.2. The INR of patients on anticoagulation therapy will have a target range indicated by their health condition, usually between 2.0 and 3.0. Higher values of 3.0 and above are targeted for patients with mechanical heart valves. Nurses often use the term "PT-INR" to refer to the blood coagulation test. Prothrombin time refers to clotting time in seconds for a sample of blood serum containing prothrombin. Prothrombin is a protein that assists with clotting. A normal prothrombin time is 12 to 15 seconds. A patient who is taking anticoagulants will have a time that is twice as long.

Until the early 1980s, the prothrombin time was used to measure the effectiveness of anticoagulation with warfarin, but different labs would come up with different times. Variability was caused by differences in the lab equipment and sensitivity of the clotting protein. To make values comparable between labs anywhere in the world, the INR was established by the World Health Organization and the International Committee on Thrombosis and Hemostasis.

Exercise Guidelines

Dr. Tuzson looked for randomized clinical trials examining the risks of physical activity in people with elevated INR, but found no such trials. She did find five studies describing hemorrhage associated with an elevated INR in patients undergoing warfarin therapy. Based on the increased risk of bleeding in patients with elevated INR, Dr. Tuzson and her colleagues developed exercise guidelines for patients with elevated INR in her acute care practice setting. She weighed in the risk factors associated with bedrest.

These guidelines can help us keep patients safe. If the INR is between 4 and 5, the patient may be allowed to participate in a PT evaluation or a familiar exercise program. The intensity of the exercise or activity should stay the same until the patient is within therapeutic range. Remember that the target INR for most patients is 2.5. If the patient is ambulatory but unsteady, PT can work on reducing risk of falls and injury, to prevent resultant hematoma. If the INR is between 5 and 6, exercise should be held. The patient can get up to a bedside commode, and the PT or PTA can assess this transfer for safety and technique, but activity should not be progressed. If the INR is greater than 6, the interdisciplinary team should be consulted and bed rest considered until the INR is corrected. Stairs and resistive exercise should definitely be avoided. In most cases, the INR will come down within two days after Coumadin is held or reduced. If the INR is very high, a vitamin K shot can be given.

Since the first rule of medicine, "Above all, do no harm," applies to PTs and PTAs as well as doctors, it pays to be cautious. While busy schedules and focus on the bottom line move us to get our treatments done, it pays to spend a few minutes reviewing nursing notes, lab values and recent MD orders.

References

1. Du Breuil, A., & Umland, E. (2007). Outpatient management of anticoagulation therapy. American Family Physician, 75, 1031-1042

2. Tuzson, A. (2009). How high is too high? INR and acute care physical therapy. Acute Care Perspectives. American Physical Therapy Association, Acute Care Section.

Emi Storey is a floating physical therapist for Consonus Rehab Services, based in Milwaukie, OR. An alumna of Stanford University, she has worked in long-term care for 15 years. Bob Thomas is a geriatric physical therapist and serves as president of Infinity Rehab, based in Wilsonville, OR. He lectures nationally for GREAT Seminars on rehabilitation for the frail elderly, and is an adjunct professor at Pacific University.