Arterial Flashcards
What are the three layers of the arterial system and their functions?
- Tunica Externa (Adventitia): Protective outer layer made of connective tissue, collagen, and elastin, providing vessel wall support.
- Tunica Media: Middle layer composed of smooth muscle, collagen, and elastin, modulating vessel diameter.
- Intimal Layer: Single layer of endothelial cells in direct contact with blood, fragile and easily traumatized.
Define arterial insufficiency and list its common causes.
Arterial insufficiency is a decrease in arterial blood supply.
- Common causes include trauma, acute embolism, diabetes mellitus, rheumatoid arthritis, thromboangiitis (Buerger’s disease), and arteriosclerosis.
What is arteriosclerosis and how does it differ from atherosclerosis?
Arteriosclerosis: Thickening and hardening of arterial walls.
Atherosclerosis: Systemic degenerative process where plaque progressively encroaches on the arterial lumen.
What are HDL and LDL, and their roles in arterial health?
HDL (High-Density Lipoprotein): Protects against cholesterol deposition.
LDL (Low-Density Lipoprotein): Enhances cholesterol deposition, contributing to plaque growth.
What is intermittent claudication, and what causes it?
Intermittent Claudication: Activity-specific discomfort caused by local ischemia, described as cramping, burning, or fatigue.
It occurs due to ~50% arterial stenosis and stops within 1–5 minutes of rest.
Differentiate between ischemic rest pain and intermittent claudication.
Intermittent Claudication: Pain during activity, relieved by rest, caused by ~50% stenosis.
Ischemic Rest Pain: Burning pain exacerbated by elevation, relieved by dependency, occurs at ~70% stenosis.
Describe the typical presentation of arterial ulcers.
Arterial ulcers are…
- dry wounds with black/gray necrotic tissue
- thin dry skin, absence of hair
- shiny appearance.
They have well-defined borders and appear ‘punched out’ with smooth edges.
What is the ‘5PT’ method for describing arterial ulcers ?
5PT:
- Pain (intermittent claudication, resting pain)
- Position (lower extremities, toes, lateral malleolus)
- Presentation (round, necrotic tissue)
- Periwound (thin, shiny skin, absence of hair)
- Pulses (decreased or absent)
- Temperature (cool)
List the risk factors contributing to arterial insufficiency ulcers.
Risk factors include hyperlipidemia, smoking, diabetes, hypertension, advanced age, and trauma.
Explain how diabetes contributes to arterial insufficiency ulcers.
Diabetes
- increases the prevalence of calcific arterial insufficiency
- impairs wound healing phases
- reduces infection resistance
- increases neuropathy risk
What is the significance of the Ankle-Brachial Index (ABI) in assessing arterial insufficiency?
ABI compares brachial BP with lower extremity BP to assess blood flow.
- Values < 0.5 all compression contraindicated
- Values 0.5-0.4 resting pain
- Values < 0.3 are associated with tissue loss.
Define rubor of dependency and its implications for arterial flow.
Rubor of Dependency: A test to assess lower extremity arterial flow.
- Blanching with elevation and bright red coloration in a dependent position indicate arterial insufficiency.
What are segmental pressure measurements, and when are they used?
Segmental Pressure Measurements:
- Identify areas of decreased arterial blood flow by comparing adjacent segments.
- A drop of >20 mmHg suggests arterial occlusion.
What adjunctive modalities are used in arterial insufficiency management?
Modalities include:
- therapeutic warmth (avoiding heating pads)
- electrical stimulation, hyperbaric oxygen
- negative pressure wound therapy.
What are the goals of local wound care for arterial ulcers?
- protecting surrounding skin
- moisturizing dry skin
- reducing friction
- padding ischemic tissues to maintain normal temperature
A patient presents with an ABI of 0.9. How should you interpret this result, and what does it suggest about the patient’s condition?
- An ABI of 0.9 suggests no significant arterial disease. This is within the normal range, indicating good blood flow.
- Values between 0.95-1.0 are generally considered normal, indicating the patient does not have significant peripheral artery disease (PAD).
You are performing a rubor of dependency test. When the patient’s leg is elevated, the foot becomes pale, and when lowered, it turns bright red. What does this indicate?
This finding suggests arterial insufficiency. When the foot turns bright red upon lowering, it indicates dependent rubor, which is a sign of impaired arterial flow and delayed capillary refill, suggesting that the patient’s arteries are not providing adequate perfusion.
A patient with a history of diabetes presents with ulcers on the toes and lateral malleolus. What additional factors would you consider in their diagnosis and treatment?
In addition to the ulcers, you would consider calcific arterial insufficiency, reduced wound healing ability, and the risk of neuropathy.
The patient’s diabetes likely affects circulation, wound healing, and infection control. Treatment would involve ensuring adequate blood flow, potentially with revascularization, and close monitoring for infection.
What is the significance of using transcutaneous oxygen measurement (tcpO2) in the evaluation of arterial ulcers, and when would this test be particularly useful?
Transcutaneous oxygen measurement (tcpO2) assesses the oxygen levels diffusing through the skin from capillary beds, providing insight into tissue perfusion. It is particularly useful when ABI values are inconclusive or when collateral circulation needs to be evaluated, as it can detect tissue hypoxia in areas with poor perfusion.
During a Doppler ultrasound exam, a patient presents with a low audible signal in the posterior tibial artery. What does this suggest, and what action should you take next?
A low audible signal in the posterior tibial artery suggests decreased blood flow, which could indicate an occlusion or stenosis.
The next step should be to perform additional testing, such as ABI, segmental pressure measurements, or arteriography, to assess the severity and location of the occlusion.
A patient with intermittent claudication reports that the pain begins after walking 200 meters and subsides with rest. How would you classify the severity of this condition and the appropriate treatment plan?
- This patient’s symptoms suggest moderate intermittent claudication, which typically occurs with 50-70% arterial stenosis.
- The treatment plan would include lifestyle changes (e.g., smoking cessation, exercise therapy), possible pharmacological interventions (e.g., pentoxifylline), and evaluating for potential revascularization if necessary.
What is the primary goal of wound care in arterial insufficiency, and why is avoiding compression critical in these patients?
The primary goal of wound care is to maintain tissue perfusion and prevent infection. Avoiding compression is critical because it can further reduce blood flow in patients with impaired arterial circulation, potentially leading to worsened ischemia, delayed healing, and increased risk of tissue damage.
What role does sympathetic block play in the management of arterial insufficiency ulcers, and when is it indicated?
Sympathetic block involves blocking sympathetic nerve signals to improve blood flow to ischemic tissues. It is indicated when revascularization is not an option, or in cases of severe pain or vascular insufficiency that does not respond to other treatments.
A 70-year-old patient with coronary artery disease presents with pale, cold feet and non-healing ulcers on the toes. What initial interventions would you prioritize for this patient?
The initial interventions should prioritize improving circulation, such as vascular assessment (e.g., ABI, Doppler), wound care, and pain management. Revascularization may be necessary, and lifestyle changes (e.g., smoking cessation, blood sugar control) should be addressed.