Deep Vein Thrombosis (DVT) occurs when a blood clot forms in a deep vein, most often in the legs or pelvis. For bedridden individuals, prolonged immobility slows blood flow, a condition known as stasis, which is the primary cause of DVT risk. If a blood clot breaks free, it can travel to the lungs and cause a pulmonary embolism, which is a medical emergency. Understanding and implementing practical prevention strategies is crucial for anyone providing care to a person confined to bed.
Understanding the Risk of Immobility
A lack of movement reduces blood flow in the lower extremities, directly causing DVT risk in immobile patients. Normally, calf and thigh muscles contract with every step, squeezing veins and pushing blood toward the heart against gravity. When a person is lying down, this natural pumping action is lost, and blood pools in the deep veins.
This blood stasis creates an environment conducive to clot formation. Several factors can elevate a patient’s risk profile further, including advanced age, a history of previous DVT, recent orthopedic surgery, and active cancer. Obesity and dehydration also increase the blood’s viscosity, compounding the risk associated with immobility.
Physical Movement and Positioning Strategies
Targeted physical maneuvers can stimulate blood circulation even when a patient cannot get out of bed. These exercises should be performed frequently throughout the day.
Active Range of Motion Exercises
Ankle pumps, where the patient points their toes toward their head and then away, engage the calf muscles to mimic the natural pumping action. This flexion and extension helps push blood out of the lower leg veins. Another strategy involves performing ankle circles, rotating the foot clockwise and then counterclockwise at the ankle joint. If the patient has upper leg mobility, a “heel slide” can be done by bending the knee and sliding the heel toward the hip while keeping the foot on the bed. These motions should be performed hourly while the patient is awake, typically aiming for 10 repetitions of each movement per hour.
Positioning and Hydration
Proper positioning promotes venous return. Caregivers should avoid placing pillows directly behind the knees, as this can compress the popliteal vein and restrict blood flow. Instead, slightly elevating the foot of the bed or using a wedge to raise the feet six inches above the heart level utilizes gravity to aid circulation. Maintaining adequate fluid intake is also important, as dehydration thickens the blood and makes it more prone to clotting.
Utilizing Mechanical Compression Devices
Specialized mechanical devices apply external pressure to the limbs, facilitating blood return to the heart. The two common forms are Graduated Compression Stockings (GCS) and Intermittent Pneumatic Compression (IPC) devices.
Graduated Compression Stockings (GCS)
GCS are tight, elastic garments that apply a specific pressure gradient. The highest pressure is at the ankle, gradually decreasing further up the leg. This gradient helps narrow the vein diameter and increases the velocity of blood flow.
Intermittent Pneumatic Compression (IPC)
IPC devices, also called Sequential Compression Devices (SCDs), use inflatable cuffs wrapped around the legs or feet. A pump intermittently fills and deflates the cuffs with air, creating a sequential squeezing action. This rhythmic compression effectively moves blood out of the deep veins, preventing stasis.
Application and Monitoring
The effectiveness of these devices depends on correct application and fit. Compression stockings must be correctly sized, as improper sizing can be ineffective or cause skin damage. IPC sleeves must be worn consistently, only being removed for movement or skin checks. Regular skin inspection is necessary beneath both types of devices to check for pressure injury or irritation.
When Medication is Necessary
For patients at high risk of DVT or following specific surgeries, a medical professional may prescribe pharmacological prophylaxis. This involves anticoagulant medications, or blood thinners, which reduce the blood’s ability to form clots. These drugs prevent new clots from forming or existing ones from growing larger, but they do not dissolve existing clots.
The most frequently prescribed agents belong to the heparin family. These include Low Molecular Weight Heparin (LMWH), typically administered via subcutaneous injection, and Unfractionated Heparin (UFH), often preferred for patients with impaired kidney function. Newer oral medications, known as Direct Oral Anticoagulants (DOACs), are also used for extended prophylaxis in some acute care settings.
These medications must only be administered under strict medical supervision, as they carry a risk of bleeding. The patient’s risk profile must be balanced between the possibility of DVT and the possibility of major hemorrhage. Monitoring for signs of unexplained bruising, blood in the urine or stool, or excessive bleeding is necessary when a patient is on anticoagulant therapy.