A condition in which the circulatory system fails to provide sufficient circulation to enable every body part to perform its function; also called hypoperfusion.
A balance of all systems of the body.
Circulation of blood within an organ or tissue in adequate amounts to meet the cell's current needs.
1) Adequate concentration of inspired O2.
2) Appropriate movement of O2 across the alveolar-capillary membrane into the arterial bloodstream.
3) Adequate # of RBC to carry O2
4) Proper tissue perfusion
5) Efficient off-loading of 02 at the tissue level
A passive process in which molecules move from an area with a higher concentration of molecules to an area with a lower concentration.
Circular muscles that encircle and, by contracting, constrict a duct, tube, or opening.
The part of the nervous system that regulates involuntary functions, such as heart rate, BP, digestion, and sweating.
Autonomic Nervous System
The volume of blood that the heart can pump per minute.
Cardiac Output (CO)
The ability of the heart muscle to contract.
The precontraction pressure in the heart as the volume of blood builds up.
The force or resistance against which the heart pumps.
What is one of the initial signs of hypoperfusion?
Altered Mental Statue (AMS)
Resistance to blood flow within all of the blood vessels except the pulmonary vessels.
Systemic Vascular Resistance (SVR)
What is the formula to determine Cardiac Output?
Cardiac Output = Heart Rate x Stroke Volume
CO = HR x SV
What is the formula to determine Blood Pressure?
Blood Pressure = Cardiac Output x Systemic Vascular Resistance
BP = CO x SVR
The BP required to sustain organ perfusion in the average person.
Mean Arterial Pressure (MAP)
What is the mean arterial pressure in the average person?
60 mm Hg
What is the formula to determine Mean Arterial Pressure?
Mean Arterial Pressure = (Cardiac Output x Systemic Vascular Resistance) + Central Venous Pressure
MAP = (CO x SVR) + CVP
What is the perfusion triangle?
The blood vessels
Receptors in the blood vessels, kidneys, brain, and heart that respond to changes in pressure in the heart or main arteries to help maintain homeostasis.
A decrease in systolic pressure to less than ___ mm Hg stimulates the vasomotor center to increase arterial pressure by constricting vessels.
Receptors in the blood vessels, kidneys, brain, and heart that respond to changes in chemical composition of the blood and help maintain homeostasis.
Where are the main baroreceptors located?
Where are the main chemoreceptors located?
Metabolism that can proceed only in the presence of O2.
The metabolism that takes place in the absence of O2.
Affecting the heart's rate of contraction.
Affecting the heart's velocity of conduction.
Affecting the contractility of the heart muscle.
A progressive condition usually characterized by combined failure of several organs, such as the lungs, liver, and kidney, along with some clotting mechanisms, which occurs after severe illness or injury.
Multiple-organ dysfunction syndrome (MODS)
Shock caused by inadequate function of the heart, or pump failure.
The presence of abnormally large amounts of fluid between cells in body tissues, causing swelling of the affected area.
Shock that occurs when there is a block to blood flow in the heart or great vessels, causing an insufficient blood supply to the body's tissues.
Compression of the heart caused by a buildup of blood or other fluid in the pericardial sac.
What is Beck's triad?
Jugular Vein Distention (JVD)
Muffled heart sounds
Narrowing pulse pressure
What is Beck's triad indicative of?
The difference between the systolic and diastolic pressures.
An accumulation of air or gas in the pleural space that progressively collapses the lung with potentially fatal results.
What is a late sign of a tension pneumothorax?
What are the two most common types of obstructive shock?
A condition that occurs when there is widespread dilation of the small arterioles, small venules, or both.
What are the four most common types of distributive shock?
Shock caused by severe infection, usually a bacterial infection.
Circulatory failure caused by paralysis of the nerves that control the size of the blood vessels, leading to widespread dilation; seen in pt. with spinal cord injuries.
Severe shock caused by an allergic reaction.
Shock caused by a sudden, temporary reduction in blood supply to the brain that causes syncope.
A condition in which the internal body temperature falls below 95oF (35oC), usually as a result of prolonged exposure to cool or freezing temperatures.
At what temperature does the body enter hypothermia?
An unusual or exaggerated allergic reaction to foreign protein or other substances.
Developing a sensitivity to a substance that initially caused no allergic reaction.
Name the four categories of allergic reactions.
Bluish color of the skin resulting from poor oxygenation of the circulating blood.
A swelling or enlargement of a part of an artery, resulting from weakening of the arterial wall.
Shock caused by fluid or blood loss.
The loss of water from the tissues of the body.
Name the three stages of shock.
The early stage of shock, in which the body can still compensate for blood loss; also called nonprogressive shock.
The late stage of shock when the BP is falling; also called progressive shock.
The final stage of shock, resulting in death.
The narrowing of pulse pressure is seen in what stage of shock?
Assessing V/s in two different pt. positions to determine the degree of hypovolemia; positive results include a increase in pulse rate and a decrease in systolic BP when changing from a lying position to a standing position.
Orthostatic Vital Signs
A drop in BP indicates the pt. has entered what stage of shock?
Most physician Dx is based on what?
If a pt. has a carotid pulse then they have a BP of at least ___.
60 mm Hg systolic
If a pt. has a femoral pulse then they have a BP of at least ___.
70 mm Hg systolic
If a pt. has a radial pulse then they have a BP of at least ___.