Perfusion: Myocardial Hemodynamics, Perfusion & Cardiac Cycle Flashcards
(256 cards)
perfusion
- the process of nutrient delivery of arterial blood to a cap bed
- supplying an organ or tissue with oxygen and nutrients
What is the purpose of invasive hemodynamic monitoring?
- The primary purpose of invasive hemodynamic monitoring is the early detection, identification, and treatment of life-threatening conditions such as heart failure and cardiac tamponade
- ii. By using invasive hemodynamic monitoring the nurse is able to evaluate the patient.
What are noninvasive assessments of perfusion?
- LOC
- Skin: Tenting of skin
- Urine output
- Low because GFR is reduced
- Color, BP, HR
a. Cyanosis
b. Hypotension
c. Volume status is low so BP goes down - Heart rate
a. Tachycardia: The heart will try to beat really fast to try to compensate - Capillary refill time
a. Longer than 3 seconds
What are 3 types of perfusion scanning methods?
- CT
- MRI
Nuclear medicine perfusion
Cardiac output is characterized by what 2 things?
HR, SV
What is stroke volume made up of?
- preload
- afterload
- contractility
What 2 things make up preload?
- Central venous pressure
2. PAWP
What 2 things make up after load?
- SVR
2. PVR
What 2 things make up contractility?
- EF %
2. SV
What is a normal CO?
4-8 liters/min.
Why is cardiac index a better indicator vs CO?
Because it corrects for body size - someone who is smaller is going to need less pump
What is a normal CI?
2.4-4.0 L/min
What is stroke volume?
volume of blood pumped with each heartbeat
What is a normal SV?
60-70 mL with each ventricular contraction
What will a change in the heart rate have an immediate change in?
Change in the CO if the SV stays constant
What does a severe increase in HR cause?
A decrease in stroke volume, due to decreased filling time. This causes the CO to decrease
Tachycardia with CO?
Reduced CO
AFIB with CO?
reduced CO
Bradycardia with CO?
Increase in CO
Why is having a slow heart rate ok with CO?
Rate is not enough but if they are athletic then their cardiovascular function is very efficient – heart rate doesn’t have to be that high to maintain good heart function.
Vtach with CO?
decrease in CO
Asystole with CO?
Reduced CO
What happens if the SV stays the same but HR goes up?
CO goes up
What is preload?
- the amount of blood in ventricle at the end of diastole
2. the amount of stretch in the myocardial fibers at the end of diastole.