Circulation of Blood
Aneurysm
Abnormal widening of arterial wall Promotes formation of thrombi that may obstruct blood flow to vital tissues Arterial walls may burst, resulting in life-threatening hemorrhaging
Pulse
Alternate expansion and recoil of the blood vessel wall
anaphylaxis, anaphylactic shock
An acute type of allergic reaction called _____ results in _____ _____.
Neurogenic Shock
Caused by nerve condition that relaxes (dilates) blood vessels and thus reduces blood flow Occurs when sympathetic stimulation is disrupted
Blood pressure gradient
Causes blood to circulate; liquids can flow only from areas of high presssure to areas of low pressure
septic shock
Complications of septicemia may result in _____ _____.
Ischemia
Decreased blood supply to a tissue
Hypovolemic Shock
Drop in blood volume that causes blood pressure (and blood flow) to drop Often caused by hemorrhage or loss of interstitial fluid, causing blood plasma to drain out of the vessels
Fetal circulation
Refers to circulation before birth
Anaphylactic Shock
Results from an acute allergic reaction Causes the same kind of blood vessel dilation that occurs in neurogenic shock
Septic Shock
Results from complications of septicemia Toxins dilate blood vessels, inducing shock
complications of toxins in the blood
Septic shock is caused by:
Precapillary sphincters
Smooth muscle cells that guard the entrance to capillaries
Tunica media
Smooth muscle, thick in arteries and thin in veins; some elastic tissue; important in blood pressure regulation
capillaries
The _____ function as exchange vessels
left ventricle
The aorta carries blood out of the:
Gangrene
Necrosis that has progressed to decay
Tunica externa
Outer layer of fibrous connective elastic tissue (heavy in veins)
Arteries
Carry blood away from the heart and toward capillaries
Capillaries
Carry blood from the arterioles to the venules; microscopic vessels
blood volume, strength of heart contractions, heart rate, blood viscosity (thickness)
4 factors that influence BP
Veins
Carry blood toward the heart and away from capillaries
Aneurysm
A section of an artery that has become abnormally widened
increases, decreases
A stronger heartbeat _____ pressure, weaker heartbeat _____ pressure
toxic shock syndrome
A type of septic shock that results from staphylococcal infections that begin in the vagina of menstruating women and spread to the blood is _____ _____ _____.
arteries, veins
Blood pressure is highest in the _____ and lowest in the _____.
pulmonary veins
Blood returns from the lungs during pulmonary circulation via the:
thickness of blood
Blood viscosity
Cardiogenic shock
Caused by heart failure
Systemic circulation
Carries blood throughout the body
Pulmonary circulation
Carries blood to and from the lungs
Varicose veins (varices)
Englarged veins in which blood pools Treatments include supporting affected veins and surgical removal of veins
Circulatory shock
Failure of the circulatory system to deliver oxygen to the tissues adequately, results in cell impairment
Capillaries
Function as exchange vessels
Arteriosclerosis
Hardening of arteries caused by calcification of fatty deposits on arterial walls Reduces flow of blood, possibly causing ischemia that may progress to necrosis (or gangrene) May be corrected by vasodilators (vessel-relaxing drugs) or angioplasty (mechanical widening of vessels), or surgical replacement
condition of low blood volume
Hypovolemia means "__________"
a drop in blood volume
Hypovolemic shock is caused by:
Ventricular septal defect (VSD)
If the foramen ovale fails to close at birth this occurs, creating a lack of oxygen
increases, decreases
Increased heart rate _____ pressure, decreased heart rate _____ pressure
Central venous pressure
Influences pressure in large peripheral veins
Tunica intima
Inner layer of of endothelial cells; only layer in capillaries
Cerebrovascular accident (CVA) or stroke
Ischemia of brain tissue caused by embolism or hemorrhage
decreases, increases
Less-than-normal viscosity _____ pressure, greater-than-normal viscosity _____ pressure
Atherosclerosis
Lipids and other matter block arteries
shunting blood from the right atrium directly into the left atrium
The foramen ovale serves the fetal circulation by:
tunica intima
The innermost coat of an artery that comes into direct cotact with blood is called the:
more
The larger the blood volume, the _____ pressure is exerted on vessel walls
sinuses
The largest veins, often called _____, are the superior and inferior vena cava.
diastolic blood pressure
The minimum arterial pressure during each cardiac cycle is known as the _____ _____ _____.
ductus venosus
The structure used to bypass the liver in the fetal circulation is the:
ductus arteriosus
The structure used to connect the aorta and pulmonary artery in the fetal circulation is the:
right atrium
The superior vena cava returns blood to the:
hemodynamics
The term _____ refers to the set of processes that influence the flow of blood.
9
There are _____ major pulse points
arteries, vein
There are two small umbilical _____ and a single, much larger umbilical _____.
True
True or False: A device called a sphygmomanometer is used to measure blood pressures in clinical situations
False; HTN
True or False: A stroke is often the result of low blood pressure
False; increase, decrease
True or False: A stronger heartbeat tends to decrease blood pressure, and a weaker heartbeat tends to increase it.
False; highest in arteries, lowest in veins
True or False: Blood pressure is highest in the veins and lowest in the arteries.
True
True or False: Both the strength and the rate of heartbeat affect cardiac output and blood pressure.
False; decreases
True or False: If blood becomes less viscous than normal, blood pressure increases
False; it would decrease
True or False: If the blood pressure in the arteries were to decrease so that it became equal to the average pressure in the arterioles, circulation would increase.
True
True or False: Loud, tapping, Korotkoff sounds suddenly begin when the cuff pressure measured by the mercury column equals the systolic pressure
False; reduces
True or False: Massive hemorrhage increases blood pressure
True
True or False: The diameter of the arterioles helps determine how much blood drains out of arteries into the arterioles
False; blood pressure gradient
True or False: The difference between two blood pressures is reffered to as blood pressure deficit.
False; artery
True or False: The pulse is a vein expanding and then recoiling
False; contraction
True or False: The systolic pressure is the maximum arterial pressure during each cardiac cycle.
False; right
True or False: The venous blood pressure within the left atrium is called the central venous pressure
Hepatic portal circulation
Unique blood route through the liver Assists with homeostasis of blood glucose levels Stores glycogen and detoxifies the blood
placenta, umbilical arteries and veins, ductus venosus, ductus arteriosus, and foramen ovale
Unique structures of the fetal circulation
Thrombophlebitis
Vein inflammation accommpanied by clot formation May result in fatal pulmonary embolism
* A strongly beating heart * An adequate arterial blood pressure * Valves in the veins * Pumping action of skeletal muscles as they contract * Changing pressures in the chest cavity caused by breathing
Venous return of blood to the heart depends on 5 mechanisms
Cardiogenic shock
_____ _____ results from any type of heart failure.
Neurogenic shock
_____ _____ results from widespread dilation of blood vessels caused by an imbalance in autonomic stimulation of smooth muscles in vessel walls.
90%
_____% of HTN cases are primary essential (idiopathic)
ischemia
decreased blood supply to a tissue
peripheral resistance
resistance to blood flow Affected by many factors, including the vasomotor mechanism (vessel muscle contraction and relaxation)
Necrosis
tissue death
gangrene
tissue that has become necrotic and begins to decay
septicemia
toxins in blood resulting from infection
Hemorrhoids
varicose veins in the rectum
Hepatic portal vein
vein in liver that exists between two capillary beds