Peripheral Vascular Assessment: Arterial vs Venous Insufficiency

Peripheral vascular assessment evaluates blood flow to the extremities and the function of arteries and veins. It helps detect peripheral artery disease (PAD), chronic venous insufficiency (CVI), and deep vein thrombosis (DVT). The assessment relies on inspection, palpation, and auscultation to evaluate pulses, skin color, temperature, capillary refill, and the presence of edema or ulcers.

Arterial vs Venous Insufficiency

Distinguishing arterial (PAD) from venous (CVI) disease is one of the highest-yield concepts on exams.

Inspection

• Dependent rubor is a reddish-bluish discoloration seen when the leg is dangling — a sign of severe arterial disease.
• Unilateral edema suggests DVT or venous insufficiency.
• Bilateral edema suggests heart failure or renal disease.
• Capillary refill: press the nail bed until it blanches; normal refill is less than 2 seconds. Delayed refill indicates poor arterial perfusion.
• Skin temperature: assess with the dorsal (back) of the hand. Cool extremities suggest arterial insufficiency; warm extremities suggest inflammation.

Peripheral Pulses

Pulse Locations

• Carotid — neck (palpate one side at a time)
• Brachial — inner elbow
• Radial — wrist
• Femoral — groin
• Popliteal — behind the knee
• Dorsalis pedis — top of the foot
• Posterior tibial — behind the medial ankle bone

Pulse Amplitude Grading (0 to 3+)

Do not document a pulse as absent without confirming with a Doppler — palpation alone may miss a weak pulse.

Special Tests

• Allen's test evaluates ulnar artery patency before radial artery puncture (e.g., ABG or cannulation). Have the patient make a fist while you compress both the radial and ulnar arteries. Release the ulnar artery; pink color returning within 5–15 seconds indicates good collateral circulation.
• Buerger's test assesses arterial sufficiency. Elevate the leg to 60 degrees for 1 minute — pallor indicates arterial disease. Then dangle the leg — rubor (redness) upon dangling indicates reactive hyperemia and severe arterial disease.
• Homans' sign (dorsiflexion of the foot causing calf pain) is an outdated test for DVT. It is no longer recommended because it can dislodge a clot. Do not use it on the NCLEX.

Common Exam Traps

• Do not confuse arterial and venous insufficiency — review the comparison table.
• Do not use Homans' sign to assess for DVT; it is outdated and dangerous.
• Do not palpate both carotid arteries simultaneously — this can cause bradycardia and syncope.
• Do not ignore unilateral leg swelling — it is suspicious for DVT until proven otherwise.
• Always compare right and left sides; asymmetry is a significant finding.

Key takeaways

• Arterial disease: cool, pale, shiny skin, diminished/absent pulses, and punched-out ulcers on the toes and pressure points. Pain worsens with elevation, improves with dangling.
• Venous disease: brown stasis discoloration, edema, and shallow ulcers around the medial malleolus. Pain worsens with standing, improves with elevation.
• Capillary refill should be < 2 seconds; delayed refill suggests poor arterial perfusion.
• Allen's test confirms ulnar patency before arterial puncture; Homans' sign is obsolete and should not be performed.
• Unilateral leg swelling = suspect DVT until proven otherwise; never palpate both carotids at once.