Air Requisite Circulatory Disorders chapters 32 33 38 Anatomy and Physiology Review Vascular system Vast network of vessels Delivers nutrients to tissues Removes metabolic wastes Blood flow is delivered proportionate to metabolic needs Systemic Pulmonary circulation aorta arteries arterioles capillaries venules veins vena cava rt atrium rt ventricle pulmonary artery arterioles pulmonary capillaries venules pulmonary vein and lt atrium Systemic and Pulmonary Circulation Primary Nursing Diagnosis ALTERATION IN TISSUE PERFUSION Think about some potential self care deficits Arteries and Veins Arteries Defining features Three layers Intima single layer of endothelial cells and elastic membrane smooth so cells flow well Media near the vessel lumen receive O2 and nutrients by direct diffusion in small arteries vasa vasorum in larger arteries Adventia connective tissue nerve fibers vasa vasorum Three types Arterioles Large elastic Medium muscular HTN Small within tissues and organs Principle point of resistance to blood flow Sharp decrease in pressure and velocity Changes from pulsatile to steady flow Veins Defining features Larger diameters Larger lumina Thinner less organized walls High volume low pressure Reverse flow is prevented by venous valves in the extremities What if the valves are damaged Veins with poor support are predisposed to irregular dilation or compression and inflammatory processes damage them easily 2 3 of all systemic blood is in veins Vascular System Arteries arterioles capillaries venules veins heart arteries When the heart contracts it forces blood out of the heart along the vascular pathways The energy generated is called the hydrostatic force Blood flow and hydrostatic force decrease as it moves farther away from the heart The volume of blood flowing from arteries to capillaries determines blood pressure blood pressure control systems 1 Arterial baroreceptor and chemoreceptor system 2 Regulation of body fluid volume 3 Renin angiotensin system 4 Vascular auto regulation Baroreceptor chemoreceptor control Hormonal Response Long term adaptive mechanisms Renin angiotension aldosterone system activated by renal system Bradykinins and histamine inflammatory response can cause vasodilation and increases in capillary wall permeability Serotonin and prostaglandins can have vasoconstrictive or vasodilator effects Regulation of body fluid volume When sodium and water levels increase the total blood volume is increases Diseases that change kidney function alter BP Renin angiotensin system Decreased blood flow to the kidneys causes renin to be released into the bloodstream This leads to the production of Angiotensin I in the liver Angiotensin I is converted to Angiotensin II in the lung by the ACE enzyme Angiotensin II is a potent vasoconstrictor which helps raise B P Angiotensin II also stimulates the adrenal cortex to produce Angiotensin III which releases Aldosterone from the adrenals which preserves sodium and water further increasing B P Assessment Accurate History Chief complaint History and physical assessment Past medical history Current meds OTC s Physical exam Blood Pressure Inspect skin hair capillary refill edema ulcers Palpate temperature Auscultate bruits turbulent blood flow B P both arms Systolic reading represents force of ventricular contraction Reflects left ventricular function Diastolic reading indicates vascular resistance afterload Pulse pressure is difference between systolic and diastolic normal 40 mmHg Taking an accurate blood pressure Proper size of the cuff Best indicator of arterial perfusion Arm at heart level Both arms supine sitting and standing 1st time Document position Repeat in arm with highest reading Assess for anxiety Timing rest five minutes between each measurement Can you take blood pressures in the leg or forearms HYPERTENSION Hypertension 50 million Americans have hypertension Prevalence Older adults African Americans Less educated lower socioeconomic groups ASHD CVA nephropathy PVD AA Untreated mortality 50 Heart Disease 33 CVA 12 renal failure When is it hypertension Normal less than 120 80 Pre hypertension 120 139 80 89 No medications Need lifestyle modifications Stage 1 hypertension 140 159 90 99 Thiazide type diuretics Consider ACEI ARB BB CCB 130 80 for patients with DM or Chronic Kidney Disease Stage 2 hypertension 160 100 Two drug combination Thiazide type diuretics ACEI ARB BB CCB The Seventh Report of the joint National Committee on Detection Evaluation and Treatment for High Blood Pressure JNC VII Healthy People 2010 What is Preload Venous return that builds during diastole ventricular stretch just before contraction How would preload change if someone is hypovolemia Afterload Resistance that the heart must overcome to achieve ejection of blood How would the left side of the heart be affected by hypertension Preload and Afterload Hypertension Characterized by type cause and severity 1 Primary essential hypertension 2 Secondary hypertension 3 4 Resistant hypertension malignant hypertension Isolated systolic hypertension 1 Refractory untreated or unresponsive to treatment 2 Is an emergency condition is unchecked Primary essential Hypertension Multifactoral with no identifiable cause Persistent progressive peripheral artery resistance Severity depends on of risk factors Length of time with hypertension Comorbid conditions Secondary Hypertension There is an identifiable cause Chronic renal disease renal artery stenosis Adrenal tumors pheochromocytoma Increased aldosterone Acute stress Pituitary tumors Genetic factors Age women over 65 men over 55 Gender men and post menopausal women Ethnicity Hispanic African American Family history Non modifiable Risk Factors for HTN Modifiable Risk Factors for HTN High Sodium diet name 5 high sodium foods Low calcium K Magnesium Diabetes Stress Obesity Nutrition Substance abuse Cigarette smoking Cocaine ETOH Caffeine Smoking Smoking affects blood vessels in two ways What are they Endothelial damage CARBON AND TAR Vasoconstriction NICOTINE Patient Education Weight Reduction Sodium restriction Fat Modification Exercise Alcohol Restriction Caffeine Restriction Relaxation Smoking Cessation Potassium Supplementation Medications ALWAYS TRY LIFESTYLE MODIFICATIONS FIRST GOAL NORMALIZE B P AND REDUCE RISK OF ORGAN DAMAGE Pharmacotherapy Diuretics Thiazide diuretics First line of therapy Diuril HCTZ Hydrodiuril Zaroxolyn Mykrox Lozol Some potassium lost Loop diuretics K wasting Bumex Lasix