Perfusion Technology Flashcards
“Perfusion” a french word means?
Pour over or through
Contractions of the heart generate blood pressure, which is responsible for moving blood through the blood vessels.
[functions of heart]
Generating blood pressure
The heart separates the pulmonary and systemic circulations and ensures better oxygenation of the blood flowing to the tissues.
[functions of heart]
Routing blood
The valves of the heart ensure a one-way flow of blood through the heart.
[functions of heart]
Ensuring one-way blood flow
[5] Route of blood flow - Deoxygenated blood
[SRR, PP]
- Superior vena cava
- Right atrium
- Right ventricle
- Pulmonary trunk
- Pulmonary arteries
[5] Route of blood flow - Oxygenated blood
[PLL, AC]
- Pulmonary veins
- Left atrium
- Left ventricle
- Aorta
- Coronary arteries
A skilled, allied health professional, trained and educated specifically as a member of an open heart, surgical team responsible for the selection, setup, and operation of a mechanical device commonly referred to as the heart-lung machine.
Perfusionist
It is needed to attach organ to sterile tubings.
Cannula
(He) Development of a roller pump in the 1930’s led to the first successful extracorporeal assist in 1953.
Dr. John Gibbon
Revolutionized the artificial lung with the development of synthesis of silicone rubber.
[name]
Kammermeyer
Developed an approach to continuously titrate coagulation with Heparin.
[name]
Bartlett and drinker
Reported the first successful cardiac ECMO run of 36 hours in a 2-year-old infant with cardiac failure.
[name]
Bartlett, Gazzaniga et. al
Provides a bloodless field for cardiac surgery.
Cardiopulmonary bypass (CPB)
It incorporates an extracorporeal circuit to provide physiological support in which venous blood is drained to a reservoir, oxygenated and sent back to the body using a pump.
Cardiopulmonary bypass (CPB)
[2] Pump
- Roller pump
- Centrifugal pump
Includes two rollers positioned on a rotating arm, which compress a length of tubing to produce forward flow.
[pump]
Roller pump
It consists of impellers/stacked cones within housing.
[pump]
Centrifugal pump
It may improve platelet preservation, renal function and neurological outcomes in longer cases.
[pump]
Centrifugal pump
It connect the patient to the circuit and hence to the CPB machine.
Cannulae
[2] Cannulae
- Venous cannulae
- Dual stage cannulae
Single-stage cannulae are used during most open-heart surgeries, where two cannulae are inserted into the superior and inferior vena cava and joined by a Y-piece.
[cannulae]
Venous cannulae
Used for most closed-heart procedures, where ba single cannula is inserted into the right atrium.
[cannulae]
Dual-stage cannulae
[2] Oxygenator
- Bubble oxygenators
- Membrane oxygenators
Largely of historical interest in the era of membrane oxygenators.
[oxygenators]
Bubble oxygenators
Consist of hollow microporous polypropylene fibres (100–200 μm internal diameter).
[oxygenators]
Membrane oxygenators
These are generally made of PVC, due to PVC’s durability and acceptable haemolysis rate.
Tubing
They collect the blood drained from the heart.
Reservoirs
[2] Types of reservoirs.
- Open reservoirs
- Close reservoirs
More commonly used.
[reservoirs]
Open reservoirs
They allow passive removal of entrained venous air along with the option of applying vacuum to assist drainage.
[reservoirs]
Open reservoirs
Have a limited volume capacity, but offer a smaller area of blood contact with artificial surfaces.
[reservoirs]
Closed reservoirs
This produces less inflammatory activation (lesser contact with foreign antigens), better sterility and reduces postoperative transfusion.
[reservoirs]
Closed reservoirs
They, however, require a separate circuit for processing suctioned blood.
[reservoirs]
Closed reservoirs
It is a method of myocardial protection where the heart is perfused with a solution to cause electromechanical arrest which reduces myocardial oxygen consumption.
Cardioplegia system
It is inserted proximally while the aortic cannula is distal to the clamp.
Cardioplegia cannula
[3] Mechanical Complications
[AVO]
- Arterial complications
- Venous complications
- Other complications
Cannulation can be associated with bleeding, cannula malposition causing selective cerebral perfusion, plaque dislodgement and dissection.
[mechanical complications]
Arterial cannulation
Cannulation can be associated with bleeding, cannula malposition/air lock causing an inadequate return, leading to cerebral and splanchnic congestion.
[mechanical complications]
Venous complication
[2] Complications
- Mechanical
- Systemic
CPB causes qualitative and quantitative platelet dysfunction.
[complication]
Systemic complication
It can occur due to cross clamping of the aorta in spite of cardioplegia.
[systemic complication]
Subclinical myocardial injury
They employ artificial blood pumps to propel open-heart surgery patients’ blood through their body tissue, replacing the function of the heart while the cardiac surgeon operates.
Perfusionists
The rate and force of heart contractions change to meet the metabolic needs of the tissues, which vary depending on such conditions as rest, exercise, and changes in body position.
Regulating blood supply
[4] Functions of the heart
- Generating blood pressure
- Routing blood
- Ensuring one way blood flow
- Regulating blood supply
It may improve platelet preservation, renal function and neurological outcomes in longer cases.
[pump
Centrifugal pump
This action can produce haemolysis and tubing debris, the incidence of which increases with time.
[pump]
Roller pump
They are made of polyvinylchloride (PVC) and are wire reinforced to prevent obstruction due to kinking.
Cannulae
Calculations are performed to determine necessary blood flow and if blood or other products are needed.
[conduct of cardiopulmonary bypass]
Pre-bypass
The deairing of CPB circuit is done by priming solutions, consisting of a mixture of crystalloids and colloids.
[conduct of cardiopulmonary bypass]
Priming
It causes haemodilution which improves flows during hypothermia. Heparin 3–4 units/ml is added to the prime.
[conduct of cardiopulmonary bypass]
Priming
During arterial cannulation, systolic pressure should be?
[initiation]
90–100 mm Hg
Perfusion pressure is used as a surrogate marker of organ perfusion and should be maintained between 50 and 70 mmHg.
[conduct of cardiopulmonary bypass]
Anesthesia and monitoring on CPB
It can cause inflammatory response and hypotension.
Acute kidney injury (AKI)
Inflammatory response and hypotension can cause acute kidney injury (AKI). Risk factors are prolonged bypass time, sepsis and diabetes.
[complication]
Systemic complications
The spectrum of cerebral injury ranges from cognitive dysfunction to stroke.
[complications]
Systemic complications
A broader term used synonymously, both include various modalities of temporary mechanical cardiopulmonary assistance used to support patients with severe heart and/or lung failure which is unresponsive to optimal conventional care.
Extracorporeal Membrane Oxygenation (ECMO) and Extracorporeal Life Support (ECLS)
Hypothermia is frequently used during CPB for its presumed organ protective effects.
[conduct of cardiopulmonary bypass]
Temperature management
Safe temperature margin:
[temperature management]
28 to 30 C
Less platelet dysfunction and higher blood flow which increases trauma.
[temperature management]
Normothermic bypass
Normothermic bypass: less platelet dysfunction and higher blood flow which increases trauma.
[conduct of cardiopulmonary bypass]
Temperature management
