Peripherial Vascular Disease (RRD #6)

peripherial vascular

A term used to describe vessels outside of the heart. Often used when describing disease processes related to these vessels.

Veins are...

thin walled vessels that take deoxygenated blood from tissue beds all over the body back to the right side of the heart

What conditions facilitate good venous return and prevent backflow?

1.) proper functioning valves in leg veins

2.) well-toned, working muscle tissue around veins

List two common peripheral venous disorders.

chronic venous insufficiency (CVI)

deep vein thrombosis (DVT)

What is venous congestion?

This occurs when blood tends to stay and sort of "settle out" of the veins of the leg and foot tissues. This occurs because of local back-pressure of the blood in the veins...not because of fluid overload.

What factors contribute to venous congestion?

gravity "winning" (ex. being on wone's feet too long) and valve incompentence.

What is the most common cause of chronic venous insufficiency?

The leg vein valves wear out and become floppy. When they don't close tightly during diastole, it will allow backflow into the distal veins of the legs and feet.

What is venous stasis?

A pool of very slowly moving / non-moving blood in the veins. It results in increased hydrostatic pressure inside the affected veins and edema in the surrounding tissue.

What are four sequelae of venous stasis?

edema in the affected area

skin breakdown in the affected area, especially over bony prominences

brownish discoloration of the skin in the affected area

varicose veins

What are contributing factors to the development of CVI?

aging, a genetic predisposition, obseity, pregnancy, job-related issues, and /or immobility, inactivity, poor muscle tone.

What is a Deep Vein Thrombosis (DVT)?

A DVT is a clot that forms on the wall of a vein, most of the time in the deep veins of the calves and thighs.

What are s/sx of a DVT?

local redness, pain, warmth, edema

s/sx are usually only unilateral

s/sx can be extreme or hardly noticeable

the patient may complain of no s/sx at all.

What is Virchow's triad?

Virchow's triad describes the three broad categories of factors that are thought to contribute to thrombosis:

injury to endothelium, stasis of blood flow, and hypercoagulability states

What is a dangerous sequela of DVT?

A DVT can break free and become a venous embolus. At that point is is possible for it to travel to the pulmonary circulation and where it can get stuck and become a pulmonary embolus.

What are the s/sx of a pulmonary embolus?

chest pain, shortness of breath (SOB), hemoptysis, shock, (potentially even death)

What kinds of interventions might nurses do to help patients with venous problems?

encourage mobility, hydration

use devices on patients' legs to help keep muscle tone strong around veins

elevate feet / legs

watch for / be careful of skin breakdown

administer blood thinners as ordered

What two things help arteries to work most efficiently?

1. How good is their muscle tone (aka. vasomotor tone)?

2. What is the state of their inner lumens (ex. is the inner lining patent and smooth)?

...these two components help to contribute to good perfusion of the distal tissues.

What is perfusion?

The process of delivery of oxygen and nutrients via the arterial system to tissue beds all over the body.

Good or bad perfusion results in good or bad tissue oxygenation and is determined by cardiac output, vasomotor tone, and lumen patency.

What s/sx are usually associated with good perfusion?

A normal / desired BP range.

normal pulses

normal capillary refill (less than or = to 2 seconds)

normal organ function.

What is atherosclerosis?

A process in which arteries become stiffer (sclerosis) and collect fat (athero) and other unwanted substances in their walls.

What causes arteries to sclerose or become hardened?

Damage from hypertension (HTN), smoking, diabetes, infection, high cholesterol, genetics, free radicals, aging.

When the intima of the arteries become damaged, collagen fibers enter the walls and stiffen them.

What causes atherosclerosis to occur?

LDLs will also deposit in the intimal lining of arteries along with collagen. When this occurs, it causes inflammatory and coagulatory responses to occur, and ultimately a plaque develops.

Where can atherosclerosis and arteriosclerosis occur?

These can occur in the lumens of arteries all over the body, reducing blood flow to distal tissues.

What is ischemia?

Hypoxia of tissues caused by an arterial circulation problem.

What are some typical s/sx of ischemia?

pain that increases with exertion and diminishes with rest (aka. ischemic pain).

diminished or absent peripheral pulses

delayed capillary refill (greater than 2 sec)

pale, cool, mottled skin

delayed healing

altered functioning of organs: heart (less cardiac output), brain (stroke), kidneys (diminished urine output)

What are some non-modifiable risk factors for arterial disease?

family history / genetics

advancing age

What are some modifiable risk factors for arterial disease?

diet / obesity / sedentary lifestyle

heavy alcohol consumption

Type II Diabetes

cigarette smoking

What is peripherial arterial disease (PAD)?

a disease of any arterial vessels outside of the heart, but is usually applied to arterial problems of the legs.

What are the symptoms of PAD?

intermittent claudication

cool, pale feet

diminished pulses (cap refill greater than 2 sec)

no hair grows on legs / shiny skin

ischemic skin ulcers.

What are the five "P's" of PAD?

(Another way to think of the s/sx of PAD)

pain, poikilothermia, paresthesia, pallor, pulselessness

When an artery is blocked by a thrombus or an emboli, where will you see the symptoms?

When an artery gets blocked, the distal tissue won't get fed with oxygenated blood. Therefore, it's a problem of distal tissue ischemia.

What is hypertension?

The consistent elevation of systemic arterial blood pressure, with normal being ~ 110/70 (or at least < 120/80).

What is primary hypertension?

The most common type of hypertension ~ 95% of the population, caused by a complex set of factors. Aka. essential or idiopathic hypertension.

What is secondary hypertension?

An uncommon type of hypertension, caused by altered hemodynamics associated with a disease process such as an adrenal tumor, renal problems, etc.

What contributes to the pathophysiology of hypertension?

atherosclerosis

overactivity of the sympathetic nervous system

overactivity of the RAAS

How does the overactivity of the sympathetic nervous system (SNS)contribute to hypertension?

too much epi released -->beta receptors of heart overstimulated -->heart rate and contractility inappropriately increased -->greater cardiac output / ejection pressure -->larger volume of blood in periphery with greater pressures = increased BP. Phew!!!

What happens when the RAAS is chronically overactive?

blood volume and pressure are chronically high

What are two sequela of an overactive SNS and RAAS?

increased arterial wall muscles = decreased elasticity and decreased lumens

damage to intimal lining with resulting inflammatory processes.

What three systems are affected by hypertension / vascular damage?

neurological system (brain / eyes)

renal system

cardiovascular system

What is an aneurysm?

A localized dilatation or outpouching of an arterial vessel wall. Usually caused by hypertensoin and atherosclerosis.

What are some areas of the body that are prone to developing aneurysms?

The vessels of the brain (causes s/sx of a stroke) and all parts of the aorta (ie. thoracic and abdominal aortic aneurysms)

What kinds of interventions might nurses do to help patients with arterial problems?

manage stress, stop smoking, drink less alcohol

nutritious diet, moderate salt and fat intake

keep LDLs low and HDLs and omega-3s high

give medications as ordered: beta blockers, ACE inhibitors, blood thinners

monitor pulses, BP, and capillary refill

check skin for breakdown / healing