Cardiac Assist Devices Flashcards
Pt being placed on bypass in times where pt is not in heart surgery
ECMO
Purpose of ECMO
Keep patients alive during acute cardiac or respiratory failure
What is venovenous ECMO?
- indicated only for respiratory failure
- blood drawn from R side
- Oxygenated by ECMO
- Returned to R side of heart
Cannula for VV ECMO
Double lumen in R atrium
- Outer lumen drains the heart and sends deoxygenated blood to ECMO
- Inner lumen infuses oxygenated blood from ECMO intro R atrium
What is venoarterial ECMO?
- Used for cardiac and respiratory failure
- Blood withdrawn from R side of heart
- Oxygenated by ECMO
- Returned to L side of heart via arterial cannula
Advantage of VA ECMO compared to VV
- VA supports the heart AND lungs, and can be used in cardiac failure
Disadvantage of VA compared to VV ECMO
- Non-pulsatile perfusion
- Potentially less oxygen delivery to the coronary arteries
- Higher chance of emboli entering arterial circulation
What is a VAD?
-Artificial heart, placed in pts with HF to help the ventricle pump blood
How does the VAD work?
- Tubing is placed inside the ventricle
- Tubing withdraws blood from ventricle into pump
- Pump pumps some blood to body through “reinfusion” tube
Benefits of VAD
Increases CO, leading to less fluid overload/edema
How does VAD increase cardiac output?
- Helps heart pump blood
2. Improves hearts ability to pump blood bc it relieves fluid overload and stretching of ventricle
What does a LVAD do?
Supports L heart failure by withdrawing blood out of L ventricle and pumping it into the aorta
What are LVADs meant for?
As a bridge to a heart transplant
Why are LVADs not meant to be a long term solution?
They carry a risk of clotting and stroke
What does a RVAD do?
Supports R HF by withdrawing blood out of the R ventricle and pumping it into the pulmonary artery