Test 1 content Flashcards
When using 4 to 1 cardioplegia set how much blood/cardioplegia solution is delivered when giving a 1000 cc dose of cardioplegia?
800cc blood and 200cc cardioplegia solution
The difference between traditional buckburg type (4:1) cardioplegia and Del Nido cardioplegia is:
Del nido is given at a ratio of 1:4
What effect does severe aortic insufficiency have on cardioplegia delivery?
Decreases aortic root pressure between the aortic cross clamp and the aortic valve
What pressure should be monitored when giving retrograde cardioplegia?
Coronary sinus
What effect does biocompatible coating have on tubing?
Internal components of the circuit “wet” more easily
The purpose of a “safety time out” in the OR is to:
Introduce OR team and discuss procedure
What factor is most important when setting up a sterile pump circuit?
Room logistics
When setting up a sterile pump circuit you should:
Use an organized routine, avoid letting the tube touch the ground and wear a mask
Coronary artery bypass graft procedures are performed on patients with:
Ischemic heart disease
One of the main differences between a roller pump and centrifugal pump when being used as an arterial pump is:
A centrifugal pump is non-occlusive
To de-air a heart is to:
flood with Co2
Del nido is a _______ tinged solution and is ___ part blood to ____ part crystaloid. Given about ___ every hour
- Blood tinged
- 1 part blood to 4 parts crystalloid
- Used about once an hour
_____Reserved for patients with end-stage heart disease not amenable to optimal medical therapy or other surgical procedures
Cardiac transplantation
End-stage cardiac failure is characterized by:
- Irreversible, severe ventricular dysfunction
- Low cardiac output
- Poor end-organ perfusion
- Activation of compensatory neurohumoral pathways
In the early stages of heart failure, stroke volume is maintained by:
- Increase in LV end diastolic volume
* Increase in myocardial fiber length
Active ingredients of del nido cardioplegia?
Plasma lyte A, mannitol 20%, sodium bicarb 8.4%, potassium chloride 2 mEq/ml, Magnesium sulfate 4.06 mEq/ml, lidocaine
(In other solutions High K+, low K+ can be used)
What is myocardial preservation?
The need to protect the myocardium from intraoperative and postoperative damage.
Addresses injury that can be caused by ischemia.
Allows surgeon to work in on a still heart.
Facilitates certain intra-cardiac procedures.
Extends the amount of time the surgeon has for certain procedures that require disrupting blood flow to the myocardium.
What is the end result of prolonged ischemia?
Tissue death!
3 Methods of myocardial preservation
Temperature
Chemical arrest
Continuous perfusion
In terms of myocardial energy consumption what uses the least or most energy?
- Beating Non working heart-LEAST
* Fibrillating heart - MOST
Solutions for chemical arrest:
Hyperkalemic solution del Nido solution Custodial solution St. Thomas solution Plegisol solution
Antegrade Cardioplegia delivery
Should monitor line pressure and/or aortic root pressure.
Aortic valve must be competent
Does not address distal ischemic heart disease (CAD)
Relatively easy to administer