APEX Cardiovascular AP Flashcards
What spreads the wave of depolarization?
Gap junctions
How does K affect RMP
Hyper K increases RMP
HypoK decreases RMP
How does CA affect THP
HyperCA increases THP
HypoCA decreases THP
Phases of ventricular AP
0 na in
1 cl in, k out
2 ca in, k out
3 k out
4 k seeps out, nakatpase
What is THP?
Voltage change that is required to achieve depolarization
SA and AV AP phases
4 depolarization, na in(i-f), ca in (t type)
0 depolarization CA in (l type)
3 Repolarization- k out
How can we influence SA nose AP?
Increase rate of phase 4 via sns
decrease THP
Increase RMP
Cardiac accelerator fibers
T1-T4
CaO2 is what?
Artierial oxygen content
20ml/O2/dL
DO2 is what range
Oxygen delivery
1000ml/min
VO2 is what
Oxygen consumption
250ml.min
cVO2 is what
Venous oxygen content
15ml/dl
CaO2 formula
(1.34 x hgb x SaO2) + (PaO2 x 0.003)
about 20m/dl is goal
Oxygen content
DO2 formula
CO x 10 x [(1.34 x hgb x SaO2) + PaO2 x 0.003)]
Delivery of oxygen- how much o2 is carried andhow fast its being delivered
reference- 1000ml
EO2 reference
reference - 25%
VO2 reference
250ml/min
cVO2 formula range
(1.34 x hgb x sao2) + (PvO2 x .003)
15ml/dl
SVR and PVR normal ranges
800-1600
150-250
dynes/sec/cm-5