Transcript Artificial Organs

Artificial Organs
BG
Index
•
•
•
•
•
•
•
•
What are artificial organs?
Artificial skin
Dialysis
Artificial pancreas
Artificial hearts
Artificial kidney
Artificial liver
Artificial lung
What are artificial organs?
• Shortage of donor organs
• Substitute for natural organs
• When organs fail to perform, artificial replace
them
• Some devices provide assistance, some replace
the organ
• Manage patients with disease by providing
transplantation
What are artificial organs?
• Either fully artificial or bio artificial
• “bio hybrid organs” are a combo of biologic and
synthetic components
• They incorporate many technologies:
 Sensors
Biomaterials
Innovative delivery systems
Artificial Skin
• When skin is damaged due to severe injury or
burn, bacteria has easy access to body fluids
• When bacteria gets in body fluids causes
“circulatory collapse” or shock
 when blood pressure in arteries is too low to
maintain an adequate supply of blood to organs
and tissues
• Prevent this they use artificial skin
Artificial Skin
• There’s an artificial skin system called “Integra”
Its an artificial substance that contains no living
components
Not designed to replace skin
Rather supplies protective covering and pliable
scaffold onto which a persons own skin cells can
regenerate on the destroyed layer or skin.
• 2 different types of skin grafts
Autologous and allograft
Artificial Skin
• Autologous skin grafts transfer skin from one part of
body to another
• Allograft transfers skin from another person
 only offer temporary cover, rejected by immune system
• Skin grafts produced by taking cells from non-burned
layer of skin, growing them into large sheets of cells then
placing cell sheets on top of Integra
• To treat burn/injury :
remove burned/damaged skin
Quickly cover with underlying tissue (artificial skin +
grown skin cells)
Dialysis
• Treatment that performs functions of kidneys
• Needed when kidneys can no longer take care of
body’s needs
• Starts with loss of kidney function of 85%-90%
• Keeps body in balance
Removes wastes, salt and extra water to prevent building
up
Keeps safe level of certain chemicals in blood
Helps control blood pressure
• Done in hospital, dialysis unit or at home
Dialysis
• 2 types: Hemodialysis + peritoneal dialysis
• Hemodialysis:
Hemodialyzer is used to remove waste, extra chemicals
and fluid from your blood
Treatments last about four hours, done three times a
week
• Peritoneal Dialysis:
Blood cleaned inside body
Catheter is placed in abdomen
Peritoneal cavity is slowly filled with dialysate
Blood stays in arteries and veins
Extra fluid and waste products are drawn out of blood
Artificial Pancreas
• Used for type 1 diabetes
• Takes over managing patients disease
• Monitors blood sugar and delivers insulin in doses
that’s for patients needs
• Designed to replicate aspects of human metabolism
 Complex progress that converts energy from food into energy
body can use
• Device incorporates measurements of physical
activity and the person metabolic response
• Size of small paper book
Artificial Pancreas
• There's an abdominal patch that continuously
measures blood sugar
• A pager sized pump that delivers insulin beneath the
skin
• Continuous glucose monitor(CGM) that channels
real-time blood sugar readings to insulin pump
 This directs pump to dispense proper amount of insulin to
keep blood sugar levels correct
• Software algorithm, linking patch and pump
 Loaded with information derived from patient
 All automated
Artificial Heart
• Provide mechanical circulatory support
• Used for severe heart failures
Heart failure is a condition where heart can no longer
provide enough blood to keep with the body’s needs.
Caused by coronary artery disease, cardiomyopathy,
heart attack, congenital heart problems
• Two types of artificial hearts:
VAD’s and TAH’s
VAD Artificial Heart
•
•
•
•
•
Ventricular Assist Devices (VAD)
Does not replace heart, works along side it
Mechanical pump
Surgically implanted next to heart
Runs on power from a battery pack that you carry at
your side, constantly helping your heart to pump
blood
• Attached to left ventricle and to aorta
• Works by helping heart pump blood from left
ventricle into aorta
• Then the blood circulates through the body
VAD Artificial Heart
• After this surgery several meds are needed to be
taken regularly, like blood thinners
• This pump can be a bridge to transplant,
keeping patient healthy while waiting for donor
heart
TAH Artificial Heart
• Total Artificial Heart (TAH)
• Device that replaces the two lower chambers of the
heart (the ventricles)
• Used for “end stage’ heart failure
 So severe all treatments have failed
• TAH is attached to hearts upper chambers(Atria)
• Between the TAH and Atria are mechanical valves
that work like the hearts own valves
• These control the flow of blood in the heart
• Two types of TAH’s (known by brand name)
CardioWest and AbioCor
CardioWest TAH
• Connected to outside power source
• Has tubes that run from inside chest to outside
power source
• Tubes exit the body and connects to a machine
that powers and controls the CardioWest TAH
AbioCor TAH
• Contained inside the chest
• Battery powered
• Battery is charged through skin with a special
magnetic charger
• Energy from the external charger reaches the
internal battery through an energy transfer
device transcutaneous energy transmission
(TET)
• Implanted TET device is connected to the
implanted battery
AbioCor TAH
• An external TET coil is connected to the external
charger
• An implanted controller monitors and controls
the pumping speed of the heart
Artificial Kidney
• One day could eliminate need for dialysis
• Device includes thousands of microscopic filters
• A bioreactor to mimic metabolic and water
balancing roles of real kidney
• Two stage system:
1. Nano scale filters and removes toxins from the blood
2. Bio cartridge of renal tubule cells mimics the metabolic
and water balance roles
• Uses hemofilter to remove toxins from blood
Artificial Kidney
• Engineering to grow renal tubule cells to provide
other biological functions of a healthy kidney
• Progress relies on body’s blood pressure to
perform filtration without needing pumps or an
electrical power supply
• Ready in about 5-7 years
Artificial Liver
• Researchers made transplantable liver grafts for rats
 May point toward successful liver transplant substitute for
humans
• The livers job is to help fight infection, clean blood,
digest food and store energy
• To be successful, artificial liver must be large to
provide enough liver function
• This requires a network of small blood vessels
(micro vascular network) to transport oxygen and
nutrients throughout the structure
Artificial Liver
• Decellularization (process of removing cells from
structure but leaving it with the architecture of
original tissue) has shown some success in other
organs
• Scientists decellularized the liver while preserving
it’s structure
• A matrix of proteins remained behind to hold livers
shape
• Using a dye showed that microvascular network in
each translucent liver was intact
• Researchers were able to successfully introduce
hepatocytes (liver cell) back into matrix
Artificial Liver
• Tested recellularized matrix, it carried out liver
specific functions at levels comparable to normal
liver
• Grafts transplanted into rats maintained their
functional hepatocytes for a few hours
• But successful engineering of an entire
functional liver will require other types of cells
• Much more work required to make long-term
functional liver grafts that can be transplanted
into humans
Artificial Lung
• Scientists mimicked structure of lung to make a
device that can use air as a ventilating gas instead of
pure oxygen
• Fashioned microfluidic channels from the polymer
polydimethylsiloxane
• Made them branch into smaller channels and the
into artificial capillaries
• Added blood and air flow outlets and inlets
• Coated all channels in polydimethylsiloxane gas
exchange membrane
• Next step for artificial lungs
Artificial Lung
• Tested with pigs blood
• Blood flowed through device from blood inlet
• Fed air into air inlet as it travelled along
channels
• Oxygen molecules diffused across gas exchange
membrane into the blood on way to blood outlet
• Blood coming from inlet was rich in carbon
dioxide
• Which would diffuse across membrane and
travel to air outlet
Bibliographies
•
•
•
•
•
•
•
•
•
Artificial Skin Fact Sheet (2008, July). In National Institue of General Medical Sciences. Retrieved May
15, 2012, from http://www.nigms.nih.gov/Education/Factsheet_ArtificialSkin.htm
Dialysis. (2012). In National Kidney Foundation. Retrieved May 15, 2012, from
http://www.kidney.org/atoz/content/dialysisinfo.cfm
Wein, H. (2010, June 28). Progress Toward an Artificial Liver Transplant. In National Institute of
Health. Retrieved May 15, 2012, from
http://www.nih.gov/researchmatters/june2010/06282010liver.htm
What Is a Total Artificial Heart?. (2010, June 1). In National Heart Lung and Blood Institute. Retrieved
May 15, 2012, from http://www.nhlbi.nih.gov/health/health-topics/topics/tah/
Ventricular Assist Device. (2012, January 26). In URMC Cardiology. Retrieved May 15, 2012, from
http://www.urmc.rochester.edu/cardiology/patient-care/treatments-procedures/ventricular-assist.cfm
Sheahan, H. (2011, July 14). No more oxygen for artificial lung. In RSC Advancing the Chemical Sciences.
Retrieved May 15, 2012, from http://www.rsc.org/chemistryworld/News/2011/July/14071101.asp
Bole, K. (2010, September 2). UCSF Unveils Model for Implantable Artificial Kidney to Replace Dialysis.
In UCSF. Retrieved May 15, 2012, from http://www.ucsf.edu/news/2010/09/4450/ucsf-unveils-modelimplantable-artificial-kidney-replace-dialysis
Can an 'Artificial Pancreas' Normalize Type 1 Diabetes?. (2011, July). In Mayo Clinic's Online Research
Magazine. Retrieved May 15, 2012, from http://discoverysedge.mayo.edu/artificial-pancreas/
Medical Devices and Artifcial Organs. (2012). In McGowan Institute for Regenerative Medicine.
Retrieved May 15, 2012, from http://www.mirm.pitt.edu/programs/medical_devices/
Pictures
•
•
•
•
•
•
•
•
•
http://www.nigms.nih.gov/Education/Factsheet_ArtificialSkin.htm
http://www.google.ca/imgres?q=dialysis&hl=en&biw=1366&bih=648&gbv=2&tbm=isch&tbnid=
HCWVGxFCxIZdM:&imgrefurl=http://vam.anest.ufl.edu/simulations/dialysissimulation.php&docid=7XlMje5JMhrhM&imgurl=http://vam.anest.ufl.edu/images/dialysis.jpg
http://discoverysedge.mayo.edu/artificial-pancreas/
http://www.google.ca/imgres?q=VAD+heart&hl=en&biw=1366&bih=648&gbv=2&tbm=isch&tb
nid=hegJ8bLy1lHpuM:&imgrefurl=http://www.nhlbi.nih.gov/health/healthtopics/topics/vad/&docid=b4V8gXSSWNoTM&imgurl=http://www.nhlbi.nih.gov/health/health-topics/image
http://www.google.ca/imgres?q=VAD+heart&hl=en&biw=1366&bih=648&gbv=2&tbm=isch&tb
nid=TCyRmTMOdS6alM:&imgrefurl=https://louisville.edu/speed/bioengineering/faculty/bioen
gineering-full/koenig/lvad-left-ventricular-assist-device.html
http://www.nhlbi.nih.gov/health/health-topics/topics/tah/
http://www.ucsf.edu/news/2010/09/4450/ucsf-unveils-model-implantable-artificial-kidneyreplace-dialysis
http://www.nih.gov/researchmatters/june2010/06282010liver.htm
http://www.rsc.org/chemistryworld/News/2011/July/14071101.asp