Peripheral Vascular Perfusion Lewis, ch 32

Arteries High pressure system Heart is pump for system Elastic, tough, thick, strong Recoil allows stretching Made of vascular smooth muscle so meds that affect VSM will affect arteries

Veins Low pressure system More veins than arteries Large diameter allows expansion of holding of large amounts of blood (capacitance vessels) Do not have pump, but valves Valves, calf muscles, and respiratory cycle facilitate venous return

Lymphatics Completely separate system of microscopic, open-ended tubes Prevents edema by siphoning excess fluid from tissue spaces that is not reabsorbed by veins Absorbs lipids from intestinal tract Conserves fluid and plasma proteins that leak out of capillaries Nodes are the filters Flow is propelled by valves, respiratory cycle, muscles and lymph vessel contractions Forms major part of immune system

Lymphatics cont’d Two main trunks: Right lymphatic that drains right side of head and neck, right arm, right thorax and lung, right heart, RUQ of liver. Empties into right subclavian vein Thoracic duct drains rest of body and empties into left subclavian

Related Organs Spleen—destroys old RBCs and stores new ones, produces antibodies, filters blood Tonsils—palatine, adenoid, lingual—respond to inflammation Thymus—develops T lymphocytes in children

Developmental Considerations Lymph tissue adult size by age 6 Twice adult size by puberty Back to adult size by age 18 Large and palpable in children (shoddy) even when not inflamed, but should not be hard, tender, or immovable Vessels and nodes atrophy and vessels grow rigid in adults

Risk Factors Arterial—same as those for CAD Venous—bedrest, prolonged sitting and standing, hypercoagulation, vein wall trauma, genetics, obesity, pregnancy, BCPs

History Leg pain Color changes (red, white, blue, brown) Ulcerations Edema Swollen glands Sx of hypertension (if any) Meds (esp hormones, antihypertensives, anticoagulants)

Physical Assessment: Arterial System Diminished or absent pulses Smooth, shiny, dry, hairless No edema Round, regularly shaped painful ulcers on distal foot, toes or webs of toes Dependent rubor Pallor and pain with legs up

Arterial cont’d Intermittent claudication Brittle, thick nails Clubbing Elevated BP Slow capillary refill Bruits

Physical Assessment: Venous, Lymph Systems Normal pulses Brown patches lower legs Dependent edema; pitting, nonpitting Irregularly shaped, usually painless ulcers on lower legs and ankles Dependent cyanosis & pain

Venous cont’d Pain relief when legs are up No intermittent claudication Normal nails Swollen lymph nodes +Homan’s sign Inflammation

Diagnostics (some on 911) Blood pressure Allen test Doppler ultrasound Duplex scanning Ankle-Brachial Index Arteriography, Venography Exercise testing D-dimer PT, PTT, INR