Nursing 3366 Pathologic Processes: Implications for NursingLecture Notes: Disorders of the Circulatory System Objectives /outcomes ( for entire circulatory system lecture ):DESCRIBE/DISCUSS/IDENTIFY: 1. influences upon and results of appropriate, forward, effective, oxygenated blood flow through the heart and peripheral system, such as normal cardiac structure, cardiac cycle, cardiac output, preload, afterload (AKA vascular resistance), contractility, neuroelectrical status of the heart, status of peripheral vessels, perfusion of tissues.2. relationship between derangements of the above structural and hemodynamic processes and the etiological factors, clinical manifestations, diagnostics, and basic treatment modalities of disorders such as: - arteriosclerosis and atherosclerosis - peripheral arterial disease - venous disorders- hypertension - coronary artery disease - stable angina and acute coronary syndrome- valvular disorders- heart failure- cardiogenic shock***************OutlineI. Overview of circulatory systemA. Potentially confusing terms B. Some key overarching conceptsII. Venous disorders A. A&P of veinsB. Peripheral venous disordersC. Treatment, nursing implications of venous problemsIII. Arterial disordersA. A&P of arteriesB. Pathogenesis of arterial disorders C. Specific arterial diseases D. Treatment, nursing implications, of arterial problems*************************************KNOW THE BASIC PATH OF BLOOD (FORWARDS AND BACKWARDS) a. See cardiac portion of the circulation notes. b. parts II & III of this lecture mostly focus on issues of flow outside theheart, or peripheral flow: aortamajor arteries in legs (ileac, femoral, popliteal) pedal arteries (D.P. & P.T.)arterioles of tissue beds of legs and feet capillary beds [gas exchange here: O2 from blood to tissue, CO2 from tissue to blood]venules veins of feet &legs inferior vena cava. 1Potentially confusing terms and Key overarching concepts can be found in the cardiac portion of the circulation notes.II. Venous disorders A. A&P of veins1. veins are thin-walled vessels that take deoxygenated blood from tissue beds all over thebody back to the right side of the heart. 2. this flow back to the heart is often called “venous return” and also sometimes called “venous drainage of tissues.” 3. conditions that facilitate good venous return (i.e., good drainage of body’s tissues) and prevent backflow (ie, prevent gravity from pulling blood downwards, away from normal return to heart) include: 2Important note: don’t confuse the valves in the veins with the valves in the heart—two very different entities.arteries—oxygenatedblood outand awayfrom heartveins—deoxygenated blood inand towardsthe heart(Arm veins & most other veins in the body have valves as well, but since there is not such a gravity problem to fight against, it is not as common to have venous disease in the arms; thus we will be concentrating on LEG vein disease.)a. proper-functioning valves in leg veins:leg veins have numerous valves which work like this:1) during systole, when blood is being pushed into arteries by the heart, the systolic pressure is also helping to push venous blood back towards the heart; vein valves in the legs are OPEN during this time.2) during diastole, the leg vein valves CLOSE so that blood doesn’t back flow & succumb to b. well-toned, working muscle tissue around the veins which “massage” the veins, helping to direct flow towards the heart during systole and also helping to prevent backflow during diastole.B. Peripheral venous disorders: chronic venous insufficiency & DVT1. overview of venous problemsa. most venous disorders occur in the legs and usually have to do with somedegree of failure to keep entire amount of venous blood flowing in its proper direction—that is upward, towards the heartb. as a result, some venous blood tends to stay and settle out in the veins of the leg and foot tissues—this is known as venous congestion (think of CONGESTION of peripheral tissues when you think of venous issues). c. factors contributing to venous congestion include:1) gravity “winning” a) ex-- simply being on one’s feet too long can cause gravity to pull fluid downward into distal leg tissues.b) unless severe, this is a type of venous congestion that is “within normal experience”—ie, not necessarily a pathologic process2) valve incompetence-- when this is the problem, a pathology is involved, and the disorder is called venous insufficiency.2. chronic venous insufficiency (CVI) a. pathogenesis / S&S: 1) CVI is most often caused by leg vein valves wearing out and becoming “floppy”—they don’t close tightly during diastole, allowing backflow into distal veins of legs & feet (venous congestion)2) this congestion can be pictured as a pool of non-moving blood in the veinsthis is called venous ______________________ and results in increasedhydrostatic pressure inside the affected veins.3) this increased pressure pushes fluid into tissues of legs and feet, causing _________________________ in the affected areaa) the edema causes mild to moderate discomfort, but over timecan also cause dry, tight skin, often with brownish discolorations b) sometimes the area becomes so engorged with edema that the skin cells cannot function properly & the tissue easily breaks down (especially over bony prominences such as heels, ankles, coccyx), causing venous ___________________________________________.4) increased hydrostatic pressure can also cause such backflow pressures to surface veins that they can become twisted & distorted– varicose veins; these are not usually a health hazard but can become painful and cosmetically distressing to your patients. b. contributing factors to development of CVI:3Mini summary concept map: Floppy valves increased hydrostatic pressure distal to the bad valves because venousblood can’t return up to heart properly engorged peripheralveins pushes fluid out to tissues edema. Edema essentially causes the main S&S of CVI: swollen, tight, dry, discolored skin which can (FYI: remember in assessing & caring for your patients that there are many causes of edema—it may be caused by venous insufficiency, but not always; other disease processes cause edema too; ex—hypoosmolar problems, HTN, right -sided heart failure, kidney disease, an injury, lymphatic problems, etc…many of