Homans’ Sign

pain or discomfort behind the knee upon passive dorsiflexion of the foot, due to thrombosis in the calf veins.

Cerebrovascular Accidents (Strokes)

Ischemic Stroke: sudden loss of function resulting from disruption of the blood supply to a part of the brain. Neurons die when they can no longer maintain aerobic respiration.

• Event usually the result of long-standing cerebrovascular disease
• early Tx results in fewer symptoms and less functional loss

5 different types

1. large thrombosis – 20%
2. small penetrating artery thrombosis – 25%
3. cardiogenic embolic stroke – 20%
4. cryptogenic 30%
5. Other – 5%

Large artery thrombosis strokes: due to atherosclerotic plaques in the large blood vessels of the brain. Thrombus formation and occlusion at the site af the atherosclerosis result in ischemia and infarction.

Small Penetrating artery thrombotic strokes: affect one or more vessels and are the most common type of ischemic stroke.

Aka lacunar strokes because of the cavity that is created once the infarcted brain tissue disintegrates.

Cardiogenic embolic strokes: are associated with cardiac dysrhythmias, usually atrial fibrillation. Emboli originate from the heart and circulate to the cerebral vasculature, most commonly the left middle cerebral artery, resulting in a stroke. Embolic strokes may be prevented by the use of anticoagulation therapy in patients with atrial fibrillation.

The 2 remaining categories of ischemic strokes are cryptogenic with no known cause and others causes such as cocaine, coagulopathies, migraine and spontaneous dissection of the carotid or vertebral arteries.

Pathophysiology:

Martin, Glenn and Porth, Carol, Mattson. 2009. Pathophysiology Concepts of Altered Health States. 8th ed. Lippincott Williams and Wilkins. Philadelphia

D-dimer testing for deep venous thrombosis

D-dimer assay is a diagnostic test used to rule-out deep venous thrombosis (DVT). The D-dimer is a degraded fibrin protein that is  present in the blood after a thrombus (blood clot) has been degraded by fibrinolysis. The D-dimer concentration may be determined by a blood assay in conjunction with other diagnostics tests such as ultrasound and angiogram to diagnose thrombosis.

Deep vein thrombosis assessment, diagnostics and treatment

Martin, Glenn and Porth, Carol, Mattson. 2009. Pathophysiology Concepts of Altered Health States. 8th ed. Lippincott Williams and Wilkins. Philadelphia

Scarvelis and Wells Clinical Assessment tool for Risk of Deep Vein Thrombosis

Scarvelis and Wells Clinical Assessment tool for Risk of Deep Vein Thrombosis

1. Active cancer (treatment within last 6 months or palliative) – 1 point
2. Calf swelling >3 cm compared to other calf (measured 10 cm below tibial tuberosity) – 1 point
3. Collateral superficial veins (non-varicose) – 1 point
4. Pitting edema (confined to symptomatic leg) – 1 point
5. Swelling of entire leg – 1 point
6. Localized pain along distribution of deep venous system – 1 point
7. Paralysis, paresis, or recent cast immobilization of lower extremities – 1 point
8. Recently bedridden > 3 days, or major surgery requiring regional or general anesthetic in past 4 weeks – 1 point
9. Alternative diagnosis at least as likely – Subtract 2 points

Assessment scoring guide:

1. Score of 2 or higher - deep vein thrombosis is likely. Follow up with diagnostic tests – imaging the leg veins.

2. Score of less than 2 – deep vein thrombosis is unlikely.

Scarvelis, D and Wells, P, S. 2006. Diagnosis and Treatment of Deep Vein Thrombosis.Journal of the American Medical Association. 175 (9) 1087-1092.