Jeff Jasinski Lab, Cardiac Review, and Cardiac Electrophysiology Recap

Question 1

Does a PICC line go into an artery or a vein?

Answer 1

vein

Question 2

What are sternal precautions?

Answer 2

1. Don’t raise arms >90 deg
2. Don’t use arms to support self or transfer
3. splint chest while coughing
4. NO ASSISTIVE DEVICE USE

Question 3

List the steps in O2 transport:

Answer 3

1. makeup of inspired air 2. airways 3. lungs & chest wall 4. diffusion 5. perfusion and gravity dependent 6. myocardial function 7. peripheral circulation 8. extraction and use of O2 9. Return of CO2 to lungs

Question 4

What is the mean O2 tension in;
Aorta
Arterioles
Capillaries

Answer 4

Aorta: 95 mmHg
Aterioles: 70-80 mmHg
Capillaries: 50 mmHg

Question 5

What is cardiac output (CO)?

What is a normal untrained CO?

Answer 5

Amount of blood pumped from L ventricle per minute. Stroke volume x heart rate.
normal untrained: 70bpm x 70mL

Question 6

At any given time, where is most of the blood volume in the cardiovascular system?

Answer 6

venous system (70%)

Question 7

What is a normal blood volume and how is distributed among plasma and RBC’s?

Answer 7

5000 mL (3000 plasma, 2000 RBC’s)

Question 8

What 4 structures are in the mediastinum?

Answer 8

esophagus, trachea, great vessels, and pericardium

Question 9

What are the muscles of inspiration?

experation?

Answer 9

inspiration: diaphragm, external intercostals, SCM, scalenes, serratous ant., pec major/minor, traps, erector spinae
expiration: All your ant/lat abdominal muscles and internal intercostals

Question 10

Which valves of the heart are inside the heart?

Which ones have papillary muscles?

Answer 10

inside the heart: mitral & tricuspid

papillary muscles: mitral (bicuspid) and tricuspid

Question 11

What is the main determinant of cardiac perfusion, systolic or diastolic pressure?

Answer 11

diastolic pressure

Question 12

Describe the course of electrical impulses along the heart.

Answer 12

SA node -> AV node -> Bundle of His -> Purkinje fibers

Question 13

What is the AV node’s job?

Where is the SA node located?

Answer 13

AV node’s job is to delay the signal to allow filling of the ventricle
SA node is located on the post. wall of the atrium

Question 14

What happens in Phase 4 of an action potential of a cardiac cell?

Answer 14

cardiac cell at rest with a - transmembrane potential.

Question 15

What happens in Phase 0 of an action potential of a cardiac cell?

Answer 15

cardiac cell stimulated, Na+ rushes in, K+ leaks out, resulting in + charge, result is depolarization. corresponds with QRS on ECG.

Question 16

What happens in Phases 1 and 2 of an action potential of a cardiac cell?

Answer 16

early repolarization, Ca2+ released, resulting in ventricular contraction. corresponds with ST segment of ECG. Phase 2 plateaus repolarization a little.

Question 17

What happens in Phase 3 of an action potential of a cardiac cell?

Answer 17

Rapid repolarization. Na/K pump returns Na & K to normal places, resulting in resting - charge. Corresponds with T wave in ECG.