5. • Machine for Cardiopulmonary bypass or Extracorporeal Circulation
system (ECC)
- For open cardiac surgery
- For supporting cardiac function, pulmonary function, or
cardiopulmonary function
• In the past >>> One unit
• Recently >>> Separate units
• Pump system (Heart)
• Oxygenator (Lung)
HEART-LUNG MACHINE
7. The first record : 1896 , a Frankfurt physician sutured
a wound in the heart of a young German solder
8. Limitation 1. Inability to operate on a heart that was still beating.
2. Stop and restart heart less than 3 minutes.
Great development : American solder in World War II
and first in congenital heart disease in 1945
9. Hypothermia - Inflow occlusion
Dr. F John Lewis was operated ASD closure using general
hypothermia and inflow occlusion (Sep 2, 1952)
10. Cross Circulation Technique
VSD closure by azygos flow concept (controlled
cross-circulation) (Dr Walton Lillehei Mar 26, 1954)
15. SCIENTIFIC DISCOVERIES
AND TECHNIQUE OF TOTAL ECC
- Temporary interruption of venous return to heart
(inflow occlusion)
- Oxygenator and roller pump
- Correlation temperature and metabolic rate
- Discovery A, B, O blood group
- Anticoagulant (Heparin) / Antagonist (Protamine)
16. TECHNIQUES FACILITATING PROGRESS OF TOTAL ECC
- Cross Circulation
- Cardiac Catheterization
- Deep hypothermia
- Myocardial arrest and myocardial defibrillator
- External Pacemaker
- Hemodilution
32. Oxygenators
Oxygenators not only supply vital oxygen for the blood, but
also transport carbon dioxide, anaesthetics and other gases
into and out of the circulation.
There are three types of oxygenator
1. Membrane oxygenators
2. Bubble oxygenator
3. Film oxygenator
33. Membrane oxygenators
Membrane oxygenators imitate the natural lung by a thin membrane of
either micro porous polypropylene or silicone rubber between the gas and blood
phases.
Diagram of a hollow fiber membrane oxygenator and heat exchanger unit. Oxygen enters
one end of the bundles of hollow fibers and exits at the opposite end. The hollow fiber
bundles are potted at each end to separate the blood and gas compartments. Oxygen
and carbon dioxide diffuse in opposite directions across the aggregate large surface of
the hollow fibers.
34. Heat Exchanger
Control body temperature by heating or cooling blood
passing through the perfusion circuit.
In heat exchanger, blood flows through spiralling coils
made of stainless steel. The inner walls of the coils are
coated with polymers to limit blood-surface interactions.
The circulating water is chilled to nearly 0 0C in an ice
bath and heated by an electric resistance coil to an
absolute maximum of 42 0C.
36. - Console Unit
- Roller Pump
- Blood level Control
- Bubble Detector
- Temperature Monitor
- Timer
- 2 channel Pressure monitor
- Venous line occluder
- Cardioplegia Control
- Halogen Console Lamp
- Gas blender and Flow meter
- Anesthetic Gas Vaporizer
Characteristics of HLM
40. - Power system 220-240 Volts 50Cycles
- Temperature 2-42 ºCelcius
- Maximum 6.5 Litre , Minimum 4.5 Litre
- Water Inlet port and outlet port for
Oxygenator, Blanket และ Cardiplegia
Heater Cooler
41. Surgical procedures in which
Heart-lung machine is used:
Coronary artery bypasses surgery.
Cardiac valve repair and/or replacement (aortic
valve, mitral valve, tricuspid valve, pulmonic valve)
Repair of large septum defects (atrial septum defect,
ventricular septum defect, atrioventricular septum defect)
Transplantation (heart transplantation, lung
transplantation, heart–lung transplantation)
Implantation of heart.
42. Complications
Haemolysis
Capillary leak syndrome
Clotting of blood in the circuit – can block the circuit
or send a clot into the patient.
Air embolism
Leakage – lose blood perfusion of tissue if a line
becomes disconnected.
1.5% of patients that undergo Heart-lung machine are
at risk of developing Acute Respiratory Distress
Syndrome.