Local/Tissue Perfusion PDF

Perfusion – Local/Tissue Lecturer: Beth Flott, EdD, RN Perfusion Definition - Flow of blood through arteries and capillaries delivering nutrients and oxygen to cells and removing cellular waste products Antecedents Defining Characteristics Positive Consequences Risk Factors Nega...

Perfusion – Local/Tissue Lecturer: Beth Flott, EdD, RN Perfusion Definition - Flow of blood through arteries and capillaries delivering nutrients and oxygen to cells and removing cellular waste products Antecedents Defining Characteristics Positive Consequences Risk Factors Negative Consequences Interrelated Concepts Exemplars Local/Tissue Perfusion Volume of blood that flows through target tissues Supplied by blood flowing from arteries to capillaries which are surrounded by smooth muscles Requires capillary hydrostatic pressure – which pushes blood through capillaries into the interstitial spaces allowing delivery of O2, fluid and nutrients to cells  Associated with abnormalities leading to occlusion, constriction, or dilation of arteries or veins Occlusion: atherosclerosis or thrombi Local/Tissue Constriction: frostbite Perfusion Dilation: aneurysms Conditions lead to ischemia, reversible cellular injury that occurs when demand for oxygen exceeds supply  Local/Tissue Perfusion Decreased oxygenation/perfusion to tissues Reduces ATP – anaerobic metabolism – lactic acid production Inability to maintain ATPase pumps – leads to potassium deficit within cells – dysrhythmias Sodium draws water in – cell swelling Membrane damage – initiates inflammatory response When ischemia persists, irreversible injury or cell death occurs Local/Tissue Perfusion Local/Tissue Perfusion Disorders of the Veins Venous Insufficiency (PVD) Altered structure and function of veins Impaired venous return leads to chronic pooling and valve damage Risks – obesity, pregnancy, standing for long periods of time Manifestations – varicosities, edema, discoloration of skin Venous Thrombosis (DVT) Risk factors Assessment findings Local/Tissue Perfusion Pulmonary Embolus Sudden onset Risks – those for DVT  Local/Tissue Perfusion Disorders of the Arteries Aneurysms Atherosclerosis main risk factor Fusiform – impacting all three layers of wall Circumferential – entire circumference of artery Saccular – one side of artery Manifestations Aneurysm Rupture  Local/Tissue Perfusion Hypertension – sustained increase in peripheral resistance, in increase in circulating blood volume, or both Primary – most cases are this type Secondary – d/t another disease process Risks Atherosclerosis and Diet SNS RAA – renin-angiotensin-aldosterone system  Hypertension Contributing factors Sympathetic nervous system (SNS) Alcohol Lifestyle factors Increased stress High salt intake Lack of physical exercise Obesity Genetics Local/Tissue Perfusion  Pre-Eclampsia – Pregnancy specific condition Cause not fully understood – placenta is root cause (decrease in placental perfusion) Local/Tissue Leads to endothelial cell dysfunction – release of toxic substance Perfusion Widespread vasospasm – decreased perfusion to all organs Hypertension – (higher than 140/90)  Pre-Eclampsia Manifestations: sudden weight gain; edema; headache; oliguria; right- sided pain; fetal distress; Local/Tissue hypertension Perfusion Eclampsia – onset of seizure activity or coma with no history of pre- existing disease Local/Tissue Perfusion Pre-eclampsia Severe form Pulmonary and neurologic/visual symptoms present HELLP Syndrome – Hemolysis (H), elevated liver enzymes (EL), low platelets (LP) Local/Tissue Perfusion  Peripheral Arterial Disease Damage to intimal layer Local/Tissue leads to decreased blood flow Perfusion Symptoms/manifestations result of lack of oxygen to cells Questions?