Packet 8 - Circulatory Function Part 2 (2)

Question 1

Conduction System

Cardiac dysrhythmias occur from alterations in cardiac conduction/rhythm that can potentially interfere with the heart’s pumping ability.

If a cardiac dysrhythmia is related to ________, there will be changes in rate (too fast or too slow), or premature ectopic beats.

a. ) altered automaticity
b. ) altered conductivity
c. ) reentry mechanisms

Answer 1

a.) altered automaticity

changes in rate, or premature ectopic beats

Question 2

Conduction System

Cardiac dysrhythmias occur from alterations in cardiac conduction/rhythm that can potentially interfere with the heart’s pumping ability.

If a cardiac dysrhythmia is related to ________, there are areas of delayed conduction, and the cells in areas where conduction is normal may have enough time to repolarize and can be depolarized again by the same impulse.

a. ) altered automaticity
b. ) altered conductivity
c. ) reentry mechanisms

Answer 2

c.) reentry mechanisms

If there are areas of delayed conduction, and the cells in areas where conduction is normal may have enough time to repolarize and can be depolarized again by the same impulse.

a electrical/cardiac impulse that is reentering an area of heart muscle that has already depolarized, and is depolarizing it again.

Question 3

Conduction System

Cardiac dysrhythmias occur from alterations in cardiac conduction/rhythm that can potentially interfere with the heart’s pumping ability.

If a cardiac dysrhythmia is related to ________, there will be conduction delays or conduction blocks that can be caused by scar tissue on the heart from a previous heart attack, electrolyte imbalances interfering with action potentials by changing the gradients so that the heart cells cannot repolarize or depolarize, or a block at the AV node.

a. ) altered automaticity
b. ) altered conductivity
c. ) reentry mechanisms

Answer 3

b.) altered conductivity

conduction delays or conduction blocks that can be caused by:

• scar tissue on the heart from a previous heart attack
• electrolyte imbalances interfering with action potentials by changing the gradients so that the heart cells cannot repolarize or depolarize
• a block at the AV node.

If you have a heart attack and have some scar tissue in your heart, that can create conduction delays or conduction blocks.

Electrolyte imbalances can interfere with action potentials, changing the gradients so that you cannot repolarize or depolarize.

Conduction delays cause parts of the heart to contract at different times, causing a drop in CO.

Question 4

Interventions for cardiac dysrhythmias include antidysrhtmic drugs that work by changing the membrane permeability of Na⁺, K⁺, and/or Ca²⁺.

If a pacemaker is not working properly, what is the next intervention?

Answer 4

If someone has a bradydysrhythmia, they are given a pacemaker.

Defibrillation provides a large electrical stimulus that has the goal of depolarizing all the heart muscle cells at the same time, so that interrupts all the disorganized impulses, allowing the SA node to reestablish itself as the normal pacemaker.

Question 5

Interventions for cardiac dysrhythmias include antidysrhtmic drugs that work by changing the membrane permeability of Na⁺, K⁺, and/or Ca²⁺.

If someone has a bradydysrhythmia, what intervention would hopefully fix this?

Answer 5

If someone has a bradydysrhythmia, they are given a pacemaker.

Provides a large electrical stimulus that has the goal of depolarizing all the heart muscle cells at the same time, so that interrupts all the disorganized impulses, allowing the SA node to reestablish itself as the normal pacemaker.