Author Question: A client has a heart rate of 78 beats per minute. Which node is most likely to produce this heart ... (Read 58 times)

ss2343 · **on:** Jul 23, 2018

A client has a heart rate of 78 beats per minute. Which node is most likely to produce this heart rate?

1. Atrioventricular (AV) node
2. Internodal pathway
3. Sinoatrial (SA) node
4. Purkinje fibers

Question 2

A nurse is reading a client's medical record and notes that the client's cardiac output (CO) is listed as 5 L/min. Which calculation was used to determine the CO?

1. Heart rate (beats/min) / stroke volume (mL/beat).
2. Systolic blood pressure heart rate (beats/min).
3. Systolic blood pressure diastolic blood pressure.
4. Stroke volume (mL/beat) heart rate (beats/min).

dreamfighter72 · **Reply #1 on:** Jul 23, 2018

Answer to Question 1

Correct Answer: 3
Rationale 1: The AV node has the ability to spontaneously generate action potentials and continue the heart's contraction at a rate of 4060 beats per minute.
Rationale 2: The internodal pathways carry action potentials from the SA node to the AV node.
Rationale 3: The SA node generates a new action potential approximately 75 times per minute.
Rationale 4: Purkinje fibers can continue to generate myocardial contractions at a rate of 30 beats per minute.
Global Rationale: The SA node generates a new action potential approximately 75 times per minute. The AV node has the ability to spontaneously generate action potentials and continue the heart's contraction at a rate of 4060 beats per minute. The internodal pathways carry action potentials from the SA node to the AV node. Purkinje fibers can continue to generate myocardial contractions at a rate of 30 beats per minute.

Answer to Question 2

Correct Answer: 4
Rationale 1: This is not the correct method of calculating cardiac output.
Rationale 2: This is not the correct method of calculating cardiac output.
Rationale 3: This is the correct method for determining pulse pressure, not cardiac output.
Rationale 4: CO = stroke volume (mL/beat) heart rate (beats/min).
Global Rationale: CO = stroke volume (mL/beat) heart rate (beats/min). The other equations are not appropriate for calculating cardiac output.