Thrombotic Disorder

Core Concepts

Virchow's triad: the three ingredients of clot formation

Almost every thrombotic disorder can be understood through Virchow's triad:

• Endothelial injury: damage to the vessel lining exposes underlying tissue that triggers platelet adhesion and clot formation. Causes include surgery, trauma, atherosclerosis, and indwelling catheters.
• Venous stasis / altered blood flow: slow or turbulent blood lets clotting factors accumulate instead of being washed away. Immobility, bed rest, long flights, heart failure, and varicose veins all slow flow.
• Hypercoagulability: blood that clots more easily than normal. Causes include cancer, pregnancy, estrogen-containing medications, genetic clotting disorders, dehydration, and smoking.

One factor alone can sometimes cause thrombosis, but in practice several often combine — for example, a post-operative patient (injury) on bed rest (stasis) with cancer (hypercoagulability).

Venous thromboembolism: DVT and PE

A DVT most often forms in the deep veins of the lower leg or thigh. Assessment cues commonly taught include unilateral leg swelling, pain or tenderness, warmth, and redness — though DVTs can also be silent, which is why prevention and risk assessment matter. The dangerous complication is pulmonary embolism: a clot fragment breaks free, travels through the right side of the heart, and lodges in the pulmonary arteries. Sudden dyspnea, pleuritic chest pain, tachypnea, hypoxia, and hemoptysis are classic PE cues, and a massive PE can cause cardiovascular collapse. PE is a medical emergency requiring immediate notification of the provider.

Arterial thrombosis

Arterial clots block oxygen-rich blood from reaching tissue. In the coronary arteries they cause myocardial infarction; in the cerebral arteries, ischemic stroke; in the limbs, acute limb ischemia (the "six P's" — pain, pallor, pulselessness, paresthesia, paralysis, poikilothermia — are a classic assessment framework). Risk factors include atherosclerosis, smoking, hypertension, and diabetes. The underlying theme is the same: a clot where it does not belong, starving tissue of oxygen.

Prevention and nursing care

Because hospitalized patients are at high risk, prevention is woven into daily nursing care:

• Early and frequent mobilization — getting patients up and moving counteracts stasis.
• Sequential compression devices (SCDs) or graduated compression stockings ordered for patients who cannot mobilize, applied per policy.
• Anticoagulant prophylaxis — blood thinners given per provider order when indicated; the nurse administers, monitors for bleeding, and documents.
• Leg elevation and avoiding prolonged sitting or positions that compress the popliteal area (such as crossed legs).

For patients with an established clot, care shifts to monitoring for embolization (new chest pain, dyspnea), managing anticoagulation (ordered lab monitoring, watching for bleeding), and teaching about activity and compression. All specifics — products, doses, monitoring targets, and protocols — follow provider orders and institutional policy, and scope of practice varies by state and setting.

Common Confusions