Cardiovascular System Part 3 W5 Flashcards
What is a cardiac arrest?
Sudden unexpected loss of contractile function of the heart
What does an AED do?
Applies an electrical shock to body to reverse abnormal arrhythmia to restore ability of the heart to pump blood
What is CPR?
Basic life support to help the heart circulate some blood to the tissues
How is blood flow delivered to exercise skeletal muscle increased?
(2 mechanisms)
1) Increased cardiac output
2) A redistribution of blood flow from inactive organs to the working skeletal muscl
What is cardiac output increase during exercise directly proportional too?
The metabolic rate required to perform the exercise
What is cardiac output?
The amount of blood pumped by the heart each minute
What is cardiac output the product of?
Heart Rate x Stroke Volume
What is heart rate?
Number of beats per minute
What is stroke volume?
Amount of blood ejected in each beat
What is end-diastolic volume?
Volume of blood in the ventricles at the end of diastole
Preload
What is frank-starling mechanisms?
Stretch of ventricles
What is average aortic blood pressure?
Pressure the heart must pump against to eject blood
Afterload
What is the strength of ventricular contraction (contractility) enhanced by?
Circulating epinephrine and norepinephrine
Direct sympathetic stimulation of heart
What is double product?
Rate-pressure product
How do you calculate double product?
Heart rate x systolic blood pressure
