8.3 blood pressure.pdf

Sri Rahaya Nafitri Abdul Razak (U6240037) 8.3. BLOOD PRESSURE 1. Blood pressure: The pressure of blood pushing against the walls of your arteries 2. Arterial blood pressure: A measure of the pressure exerted by the blood as it flows through the arteries 3. Systolic pressure: The...

Sri Rahaya Nafitri Abdul Razak (U6240037) 8.3. BLOOD PRESSURE 1. Blood pressure: The pressure of blood pushing against the walls of your arteries 2. Arterial blood pressure: A measure of the pressure exerted by the blood as it flows through the arteries 3. Systolic pressure: The pressure of the blood as a result of contraction of the ventricles, that is the pressure of the height of the blood wave 4. Diastolic pressure: The pressure when the ventricles are at rest 5. Pulse pressure: The difference between the diastolic and the systolic pressures 6. Arteriosclerosis: Occurs when the blood vessels that carry oxygen and nutrients from the heart to the rest of the body (arteries) become thick and stiff 7. Hypertension: A blood pressure that is persistently above normal 8. Hypotension: The blood pressure is below normal Measurements of Blood Pressure : 120/80 mmHg 4 Factors Determinants of Blood Pressure 1. Pumping action of the heart: Ÿ Pumping action of the heart weak, blood pumped into arteries low (cardiac output low) and BP low. Ÿ Pumping action strong, blood pumped into circulation increases (high cardiac output), and BP high. 2. Peripheral vascular resistance: Ÿ Peripheral resistance can increase blood pressure especially diastolic pressure. Ÿ Factors that create resistance in the arterial system: capacity of the arterioles and capillaries, the complience of the arteries and the viscosity of the blood. Ÿ Internal diameter or capacity of the arterioles and capillaries determines in great part the peripheral resistance to the blood in body Ÿ The smaller space within a vessel, the greater the resistance. Ÿ Arterioles in the state of partial constriction. Ÿ Increased vasoconstriction (increase BP); smoking, decrease vasoconstriction (decrease Bp). Ÿ If elastic and muscular tissues of the arteries are replaced with fibrous tissue, the arteries lose much of their ability to constrict and dilate, common in middle aged and older adults, known as arteriosclerosis. 3. Blood volume: Ÿ Blood volume decrease, Bp decrease because of fluid in arteries decrease (haemorrhage n dehydration) Ÿ Blood volume increase, Bp increase because of greater fluid volume in circulation (rapid intravenous infusion) 4. Blood viscosity Ÿ Bp high when blood is highly viscous (thick) Ÿ The proportion know as haematocrit of red blood cells to the blood plasma is high Ÿ The viscosity increases markedly when haematocrit more than 60% to 65%. Describe 10 Factors Affecting Blood Pressure - Age: Ÿ The pressure rise with age Ÿ In older adults, elasticity of the arteries is decrease, the arteries are more rigid and less yielding to the pressure of the blood (systolic pressure high) Ÿ The walls no longer retract as flexibly with decrease pressure (diastolic pressure high) - Exercise: Ÿ Physical activity increases the cardiac output and hence the Bp. For assessment, ask pt to rest for 20/30 mins before take the Bp - Stress: Ÿ Stimulation of the sympathetic nervous system increase cardiac output and vasoconstriction arterioles, so Bp high Ÿ Severe pain can decrease Bp by inhibiting the vasomotor center and producing vasodilation - Race: Ÿ African Americans older than 35 y/o tend to have higher Bp than European Americans of the same age although the reasons for these differences are unclear - Sex: Ÿ After puberty, female low Bp than male of the same age, due to hormones Ÿ After menopause, female have high Bp than before - Meds: Ÿ Many meds, including caffeine can increase or decrease Bp - Obesity: Ÿ Both childhood and adult obesity predispose to hypertension - Diurnal variation: Ÿ Bp lowest early in the morning when metabolic rate is lowest Ÿ Bp rise the days and peaks in the late afternoon or early evening - Medical conditions: Ÿ Any condition affecting the cardiac output, blood volume and/or compliance of the arteries has a direct effect on the Bp - Temp: Ÿ Metabolic rate high, fever can increase Bp Ÿ External heat causes vasodilation and decrease blood pressure Ÿ Cold causes vasoconstriction and elevates blood pressure Define Nursing Assessment for Orthostatic Hypotension (Bp decrease when the clients sits/stands) Ÿ Place the client in a supine position for 10 mins Ÿ Record the client's Bp Ÿ Assist the client to slowly sit or stand. Support the client in case of faintness Ÿ Immediately recheck the Bp in the same site as previously Ÿ Repeat the pulse and Bp after 3 mins Ÿ Record the results. A drop in Bp of 20mmHg systolic or 10 mmHg diastolic indicates orthostatic hypotension Assessment Blood Pressure Instruments Label the instruments part Ÿ Stethoscope Ÿ Sphygmomanometer Ÿ Blood pressure cuff What are the sizes of cuff is available? Ÿ Newborn Ÿ Infant Ÿ Child Ÿ Adult Ÿ Large adult Ÿ Thigh What is the Appropriate Size of the Length of the Bladder Cuff? Ÿ The bladder of a blood pressure cuff is 40% of the arm circumference or 20% wider than the diameter of the midpoint of the limb List the Bp assessment Site Ÿ Brachial artery: taken on the upper arm mostly Ÿ Radial artery: taken on the lower arm; possible site for infants or client who have a very large upper arm Ÿ Popliteal artery: thigh Ÿ Dorsalis pedis and posterior tibial: taken on the lower leg METHODS In Bp measurement using a stethoscope, five phases in the series of sound called Korotkoff’s Sounds 1) Phase 1: the pressure at which the first faint clear tapping sounds are heard. 2) Phase 2: the period during deflation when the sounds have a swishing quality, 3) Phase 3: the period during which the sounds are crisper and more intense. 4) Phase 4: the time when the sounds become muffled and have a soft, blowing quality. 5) Phase 5: the pressure level when the sounds disappear. Assessing Blood Pressure 1. Purpose to obtain a baseline measure of arterial blood pressure for subsequent evaluation. 2. Assessment Signs and symptoms of hypertension, hypotension, and factors affecting blood pressure. 3. Planning/ Preparation a) Equipment = 1) stethoscope 2) sphygmomanometer 3) blood pressure cuff b) Patient i. Client has not smoked or ingested caffeine within 30 minutes. ii. The bladder of the cuff must at least ⅔ of the arm and the width must be appropriate. iii. Position of the client is in a sitting position. The arm should be flexed with the palm of the hand facing up and the forearm supported at heart level. c) Nurse 1) introduce themselves. 2) explain the procedure to the patient. 3) ask the patient their names and birth date and check their wrist band. 4) make sure all the instruments are ready, for example; stethoscope, blood pressure cuff and sphygmomanometer. 5) position the client appropriately. 4. Implementation 1) preparation: ensure that the equipment is intact and functioning properly. Also, to make sure that patients don’t take any hot drinks, hot food, caffeine and smoking within 30 minutes prior to measurement. 2) performance: perform hand hygiene and observe appropriate prevention procedures. Other than that, nurses should provide privacy for their patients. 5. Evaluation i) The blood pressure in relation to baseline data, normal range for age, and health status; relationship to pulse and respirations.