PAD Flashcards
MC sites for PAD
Carotid bifurcation
Proximal left anterior descending coronary artery (LAD)
Proximal renal arteries
Abdominal aorta
PAD: Why is screening important?
- Marker for cardiovascular morbidity & mortality
- Risk of death from MI & stroke triples
- sign of functional decline
PAD risk factors
- Diabetes
- Smoking
- Obesity (BMI >30)
- HTN
- High Cholesterol
- older age
- Family hx of PAD, CAD
- High levels of homocysteine (AA in blood with high meat diet)
PAD pathophysiology
- Atherosclerotic ds: chronic inflammatory ds initiated by injury (smoking/HTN)
- damage to vascular endothelial cells -> plaque formation -> narrow lumen -> obstruction
- obstruction = decreased perfusion to meet metabolic demands -> ischemia + SYMPTOMS
PAD: collateral circulation
Collateral circulation: blood flow shifts to smaller arteries which parallel the disease artery
- anastomoses between branching networks of smaller arteries can increase in size over time to form collateral circulation that perfuses structures distal to the occlusion
PE/DVTs: Thromboembolic disorders, Superficial venous thrombosis
DVT in upper extremities = 10% of DVT cases
- IATROGENIC causes: catheters, pacemakers, ICDs
Superficial venous thrombosis: 1/3 of pts have DVT/PEs
Thromboembolic disorders:
- 1/3 of pts have PEs with 1/4 of the cases present with SUDDEN DEATH
never miss PE!!!!!
Arterial anatomy + plaque formation
Three concentric layers:
- intima (innermost - plaque formation begins here!!!)
- media
- adventitia (outermost)
Intima:
- plaque formation begins here where LDLs undergo modification -> local inflammatory response that attracts phagocytes and become FATTY streaks
- atheroma starts to form: FATTY LAYER
Intima function
Intima: remarkable metabolic properties
- Synthesizes regulators of thrombosis: helps with stopping bleeding
- Controls influence on blood flow: widens or narrows
- Regulates immune & inflammatory reactions
large vs medium vs small arteries and role in arterial flow
size vary according to their distance from the heart
- large = HIGHLY ELASTIC: aorta, common carotid, iliac
- medium sized = muscular: coronary and renal arteries
- small = ARTERIOLES = RESISTANCE TO BLOOD FLOW HERE -> principal determinant of systemic vascular resistance
- capillaries = rapid diffusion of O2 and CO2; ENDOTHELIAL cell lining with no media
what contributes to the propagation of blood flow and arterial pulsatile flow?
elastic recoil and smooth muscle contraction and relaxation in the media of LARGE- and MEDIUM-sized arteries
Palpating pulses in the arteries of the arm: brachial, radial, ulnar, hand vascular arches
Brachial artery: at the bend of the elbow
- MEDIAL to the biceps tendon in antecubital crease
- flex elbow slightly
Radial artery on the LATERAL flexor surface of wrist
- finger pads on flexor surface of wrist -> compare b/l pulse
Ulnar artery on the MEDIAL flexor surface
- overlying tissues may obscure pulsations in the ulnar artery
hand: vascular arches
-connect the radial and ulnar arteries
-protect circulation to the hand and fingers from arterial occlusion
Celiac trunk, superior mesenteric artery, inferior mesenteric artery
Celiac trunk: esophagus, stomach, proximal duodenum, liver, gallbladder, pancreas, spleen (foregut)
Superior mesenteric artery: SMALL intestine—jejunum, ileum, cecum; LARGE intestine—ascending and transverse colon, up to right splenic flexure (midgut)
Inferior mesenteric artery: LARGE intestine—descending and sigmoid colon, proximal RECTUM (hindgut)
acute mesenteric ischemia = life threatening
femoral, popliteal, posterior tibial, dorsalis pedis
Femoral: below inguinal ligament
- NAVEL: nerve, ARTERY, vein, empty, lymphatics
- palpate midway between the anterior superior iliac spine and the symphysis pubis
Popliteal:
- passes medially behind the femur
- palpable behind knee
- place fingertips midline + deeply press into popliteal fossa
Posterior tibial:
- behind and slightly below medial malleolus of ankle
Dorsalis pedis: dorsum of foot;
- palpate lateral to extensor tendon of big toe
Venous system characteristics
- THIN WALLED
- highly distensible -> can hold up to 2/3 of circulating blood
- ONE WAY VALVES (unidirectional): promote venous return to the heart, prevent pooling, prevents backward flow
which veins connect saphenous/superficial vein system with deep system
PERFORATING VEINS
Deep veins vs superificial veins
Deep veins:
- carry 90% of venous return from lower extremities; well supported
Superficial veins:
- great saphenous : joins with femoral vein just below inguinal ligament
- small saphenous: joins the deep venous system in the popliteal fossa
- poor tissue support
- anastomotic veins connect the two saphenous veins
what serves as venous pump
-Contraction of calf muscles serves as venous pump during WALKING
-Propelling blood upward against gravity
Lymphatic system definition
Lymphatic system: drains lymph fluid from body tissues and returns it to VENOUS circulation
- start as lymphatic capillaries (little vacuums in spaces between cells)
- capillaries -> vessels which then pass through lymph NODES
-LNs: filtration points along vessels that remove pathogens, debris from the fluids + PRODUCE ANTIBODIES
- ROLE IN BODY’S IMMUNE SYSTEM
Lymph node description
- filtration points along vessels that remove pathogens, debris from the fluids + PRODUCE ANTIBODIES
- round, oval, bean shaped structure
- only superficial LNs palpable on PE
Lymphatic system: major ducts + where they drain into
right lymphatic duct: draisn into the R internal jugular and subclavian veins
thoracic duct: drains into the L internal jugular and subclavian veins
LNs: lower limb palpating
superficial group: horizontal and vertical group
- horizontal: just below inguinal
- vertical: near great saphenous
- note size, consistency, tenderness
- can palpate discrete nodes that are up to 1-2 cm in normal person
Horizontal:
- drains superficial lower abdomen and buttock, external genitalia (minus testes), anal canal, perianal area, vagina
Vertical:
- leg
palpate epitrochear LNs
- flex elbow 90 degrees while supporting forearm
- feel in groove between biceps and triceps
- 3cm above medial epicondyle
palpable LNs: signals generalized lymphadenopathy or infection:
- syphillis
- HIV
Lymphatic drainage of the upper extremities:
Ulnar surface, hand, 3rd, 4th fingers -> epitrochlear LNs -> axillary LNs
warning signs of PAD
-Fatigue, aching, numbness, or pain that limits walking or exertion in the legs; if present, identify the location
- ED
- poorly healing or nonhealing wounds of the legs or feet
- Any pain present when at rest in the lower leg or foot and changes when standing or supine
- Abdominal pain after meals with associated FOOD FEAR and weight loss
- first-degree relatives with an AAA
