tailieunhanh - Lecture Human anatomy and physiology - Chapter 19: The cardiovascular system: Blood vessels (part b)

Chapter 19 - The cardiovascular system: Blood vessels (part b). Learning objectives of this chapter include: Define blood flow, blood pressure, and resistance, and explain the relationships between these factors; list and explain the factors that influence blood pressure, and describe how blood pressure is regulated; define hypertension. Describe its manifestations and consequences;. | 19 The Cardiovascular System: Blood Vessels: Part B Monitoring Circulatory Efficiency Vital signs: pulse and blood pressure, along with respiratory rate and body temperature Pulse: pressure wave caused by the expansion and recoil of arteries Radial pulse (taken at the wrist) routinely used Figure Common carotid artery Brachial artery Radial artery Femoral artery Popliteal artery Posterior tibial artery Dorsalis pedis artery Superficial temporal artery Facial artery Measuring Blood Pressure Systemic arterial BP Measured indirectly by the auscultatory method using a sphygmomanometer Pressure is increased in the cuff until it exceeds systolic pressure in the brachial artery Measuring Blood Pressure Pressure is released slowly and the examiner listens for sounds of Korotkoff with a stethoscope Sounds first occur as blood starts to spurt through the artery (systolic pressure, normally 110–140 mm Hg) Sounds disappear when the artery is no longer constricted and blood is flowing freely (diastolic pressure, normally 70–80 mm Hg) Variations in Blood Pressure Blood pressure cycles over a 24-hour period BP peaks in the morning due to levels of hormones Age, sex, weight, race, mood, and posture may vary BP Alterations in Blood Pressure Hypotension: low blood pressure Systolic pressure below 100 mm Hg Often associated with long life and lack of cardiovascular illness Homeostatic Imbalance: Hypotension Orthostatic hypotension: temporary low BP and dizziness when suddenly rising from a sitting or reclining position Chronic hypotension: hint of poor nutrition and warning sign for Addison’s disease or hypothyroidism Acute hypotension: important sign of circulatory shock Alterations in Blood Pressure Hypertension: high blood pressure Sustained elevated arterial pressure of 140/90 or higher May be transient adaptations during fever, physical exertion, and emotional upset Often persistent in obese people Homeostatic Imbalance: Hypertension Prolonged hypertension is a major cause | 19 The Cardiovascular System: Blood Vessels: Part B Monitoring Circulatory Efficiency Vital signs: pulse and blood pressure, along with respiratory rate and body temperature Pulse: pressure wave caused by the expansion and recoil of arteries Radial pulse (taken at the wrist) routinely used Figure Common carotid artery Brachial artery Radial artery Femoral artery Popliteal artery Posterior tibial artery Dorsalis pedis artery Superficial temporal artery Facial artery Measuring Blood Pressure Systemic arterial BP Measured indirectly by the auscultatory method using a sphygmomanometer Pressure is increased in the cuff until it exceeds systolic pressure in the brachial artery Measuring Blood Pressure Pressure is released slowly and the examiner listens for sounds of Korotkoff with a stethoscope Sounds first occur as blood starts to spurt through the artery (systolic pressure, normally 110–140 mm Hg) Sounds disappear when the artery is no longer constricted and blood is flowing freely