Perf Tech Test 5 Flashcards
Coronary Blood Flow determined by 2 factors
- perfusion pressure
- coronary vascular resistance
Delivery of Oxygen 2 factors
- coronary blood flow
- oxygen content
Coronary Perfusion Pressure (eq)
CPP= DBP - LVEDP (or LAP)
normal= 60-80 mmHg
Pre-ischemic Interventions
- minimize on going ischemia (drugs)
- prevent distention (vent)
- preconditioning (periodically introduce ischemia)
Why give CPG
inactive heart, bloodless field, persevere muscle, lower O2 demand
Cardiac Action Potential Phases
0-Na in 1- little K out 2- Ca in (contraction) 3- K out 4- Na/K pump
3 Types of Cardioplegia
- Potassium Arrest= high K, no 3
- Custodial HTK= low Na, no 0 (mimics intracellular)
- Del Nido 1:4= low Ca, no 2 (mimics extracellular- plasmalyte based)
Antegrade Pressure and Flow
in line pressure= 125-150, Aortic Root= 50-100
flow= 250-400 ml/min
Retrograde Pressure and Flow
coronary sinus pressure= 30-40
flow= 200 ml/min
Direct Ostial Delivery Pressure and Flow
circuit pressure= 250-300 (high cuz small hole)
flow= 150-250 (normal CO 5-8%)
Delivery through Graft
pressure= 50 flow= 50-100 ml/min
KCl
diastolic arrest
THAM/histadine
buffer
Mannitol
osmolarity, free radical scavenger
Aspartate/glutamate/glucose
metabolic substrate