Concepts of Cardiopulmonary Bypass Flashcards
Definition of a Perfusionist
A perfusionist is a certified medical technician responsible for extracorporeal oxygenation and flow of the blood during open-heart surgery and for the operation and maintenance of equipment (such as a heart-lung machine) controlling it.
Perfusionist Responsibilities
- Setting up, operating and maintaining complex perfusion equipment
- Monitoring circulation
- Regulating the levels of oxygen and carbon dioxide in the blood
- Regulating the body temperature
- Measuring laboratory values such as arterial/venous blood gases
- Administering medication and blood products via the bypass circuit under the supervision and direction of the anesthesiologist and surgeon
Circuit Components
♥ Oxygenator / Heat Exchange Unit
♥ Pump Head
♥ Venous Reservoir
♥ A-V Loop
♥ Arterial Filter
♥ Filtered Cardiotomy
♥ Cardioplegia Delivery System (MPS)
♥ Autologous Blood Conservation Technologies (Cell Saver)
Pump Prime
♥ Normosol
♥ 10,000 units Heparin
♥ 200 cc 25% Mannitol
♥ 50 mEq’s Bicarb
♥ 200 mg Lidocaine
♥ 80 mEq’s K+
♥ 5 grams Magnesium
What is the AV Loop?
♥ The AV Loop is the connection of the patients venous system to the patients arterial system with an extracorporeal circuit
♥ Venous cannula drains RA into the venous reservoir.
♥ Arterial line returns filtered blood through cannula which is inserted into the aorta
Cannulation Placement
Arterial Cannulation
♥Cannula inserted into ascending aorta to deliver oxygenated blood to the body
MUST BE BUBBLE FREE
Venous Cannulation
♥ 2-stage cannula inserted into right atrium. Basket in mid cannula sits in right atrium to drain upper body and basket at the tip sits in the inferior vena cava to drain the lower body
♥ Drainage is done by gravity but a vacuum can be added if necessary
Venous Reservoir
♥ Closed and open systems
♥ Defoamer, nylon sock, filtration media & screens
♥ Acts as the atrium of the heart-lung machine circuit
Venous Drainage
♥ 2-stage cannula inserted into the right atrium and connected to ½’’ pump tubing
♥ Drainage is achieved by gravity & vacuum
♥ Vaccum can be added to assist in drainage to gain more patient volume & empty the heart if needed
Venous O2 Saturation Monitor
♥ Constant in-line measurement of both venous O2 saturation and hct
♥ Good tool to tell whether adequate perfusion is being achieved
Which is a Better SVO2?
A
SVO2 50%
FIO2 100%
C.O. 3.0 LPM
B
SVO2 82%
FIO2 80%
C.O. 3.2 LPM
B
SVO2 82%
FIO2 80%
C.O. 3.2 LPM
Bubble Detector
♥ Safety mechanism which protects patient from receiving an air embolus
♥ Easily placed on any portion of pump tubing
E Clamp
The E Clamp is a safety device that is attached to the arterial line.
It’s function is to stop arterial flow to the patient when either air or low blood volume is detected
Pump Technology–Roller Pump
Positive Displacement
Pump Technology–Centrifugal pump
Centrifugal pump
♥ Non-occlusive constrained vortex
♥ Safer than roller pump
♥ Less traumatic to the formed elements of blood
♥ Maintains systemic circulation
♥ All pump types are hemolytic to some degree Hemolysis increases logarithmically over time.
Pump Console
♥ This is the “ Heart “
♥ Allows adjustment in raising or lowering blood flow. In other words managing patient’s cardiac output.
LPM!!!
Oxygenator–Heat Exchanger
♥ Integrated Hollow fiber membrane unit
♥ Stainless steel bellows heat exchange unit
♥ Plastic housing
♥ Urethane potting material
♥ Primary function is the oxygenation & removalof CO2 from blood.
♥ This is the “Lung”
♥ Secondary Function is blood temperature management
