Dialysis procedure

1. Dialysis
By: Naseem abu hawas

2. Kidneys – Facts and Function
• The kidneys have three main functions:
1- Control concentrations of body fluids,
2- Rid the body of unwanted soluble waste
3- Regulate a proper acid-alkaline environment in
the body for proper chemical reactions Even
small variances may result in death.

3. Kidney Failure
• Kidney failure, or renal failure, occurs when the kidneys
fail to function adequately.
1- Acute renal failure - Definition
• Acute renal failure (ARF) occurs when a rapid loss of
renal function results in poor urine production,
electrolyte disturbance, and fluid balance disturbance
2- Chronic Renal Failure - Definition
• Chronic renal failure (CRF) or chronic kidney disease
(CKD) occurs when a progressive loss of kidney function
occurs over a period of months to years.

4. Dialysis - Definition
• Dialysis is an artificial process used to remove water and
waste substances from the blood when the kidneys fail to
function properly.
• It generally works through osmosis and filtration of fluid
across a semipermeable membrane with the use of a
dialysate.
• Principle :Dialysis works on the principles of the
diffusion of solutes and ultrafiltration of fluid across a
semi-permeable membrane.
• Diffusion describes a property of substances in water.
Substances in water tend to move From an area of high
concentration To an area of low concentration.

5. Semipermeable Membrane - Definition
• A semipermeable membrane is a thin layer of material that
contains various sized holes, or pores. Smaller solutes and
fluid pass through the membrane, but the membrane blocks
the passage of larger substances (for example, red blood cells,
large proteins).
Dialysate –:
• Dialysate is a Solution containing ultra pure water and
chemicals (electrolytes) that passes through the artificial
kidney to remove excess fluids and wastes from the blood.
Urea and other waste products, potassium, and phosphate
diffuse into the dialysis solution. Concentrations of sodium
chloride are similar to those of normal plasma to prevent loss.

6. • In medicine, a shunt is a hole or a small passage
which moves, or allows movement of, fluid from
one part of the body to another. The term may
describe either congenital or acquired shunts;
and acquired shunts (sometimes referred to
as iatrogenic shunts) may be
either biological or mechanical.

9. Catheter (shunt)Types:
• Catheters are usually found in two general varieties,
tunnelled and non-tunnelled.
1-Non-tunnelled catheter access is for short-term access
Up to about 10 days
Often for one dialysis session only
Catheter emerges from the skin at the site of entry into
the vein.

10. • 2-Tunnelled access involves a longer catheter
Tunnelled” under the skin From the point of insertion in
the vein exit site some distance away placed in the
internal jugular vein Exit site is usually on the chest wall.
The tunnel acts as a barrier to invading microbes, and as
such, tunnelled catheters are designed for short- to
medium-term access (weeks to months only), because
infection is still a frequent problem.

11. Example of shunt :
• Cardiac shunts may be described as right-to-left,
left-to-right or bidirectional, or as systemic-to-
pulmonary or pulmonary-to-systemic.
• Cerebral shunt: In cases of hydrocephalus and other
conditions that cause chronic increased intracranial
pressure, a one-way valve is used to drain
excess cerebrospinal fluid from the brain and carry
it to other parts of the body. This valve usually sits
outside the skull, but beneath the skin, somewhere
behind the ear.

12. • Lumbar-peritoneal shunt: In cases of chronic
increased intracranial pressure such as Hydrocephalus, a
tube or shunt with or without a one-way valve is used to drain
the excess cerebrospinal fluid from the brain and transport it
to the peritoneal cavity, which is a cavity located in the
abdomen area of the body. This shunt is usually inserted in
between two of the vertebrae in the lumbar and punctures the
cerebrospinal fluid sack or lumbar subarachnoid space, it then
runs beneath the skin to the peritoneal cavity, where it is
eventually drained away by the normal bodily fluid drainage
system.[
• A Peritoneovenous shunt: is a shunt which drains peritoneal
fluid from the peritoneum into veins, usually the internal
jugular vein or the superior vena cava.

13. Catheter Problems
1- Infection (frequent)
• tunnelled catheters are designed for short-to
medium-term access weeks to months only
• Venous Stenosis (serious)
• Foreign body in the vein
2- Venous stenosis
• Results in scarring and narrowing of vein
3- Can cause problems with severe venous
congestion in the area drained by the vein

14. How dialysis is performed
• There are two main types of dialysis: haemodialysis
and peritoneal dialysis.
1-Haemodialysis involves diverting blood into an
external machine, where it's filtered before being
returned to the body
2- Peritoneal dialysis involves pumping dialysis fluid
into the space inside your abdomen (tummy) to
draw out waste products from the blood passing
through vessels lining the inside of the abdomen.

15. Haemodialysis
Preparing for treatment
• Before haemodialysis start, will usually need to have a special
blood vessel created in patient arm, called an arteriovenous
fistula (AV fistula). This blood vessel is created by connecting
an artery to a vein.
• Joining a vein and an artery together makes the blood vessel
larger and stronger. This makes it easier to transfer your
blood into the dialysis machine and back again.
• The operation to create the AV fistula is usually carried
out around four to eight weeks before haemodialysis begins.
This allows the tissue and skin surrounding the fistula to heal.
• If blood vessels are too narrow to create an AV fistula, an
alternative procedure known as an AV graft may be
recommended. A piece of synthetic tubing (graft) is used to
connect the artery to the vein.
• As a short-term measure, or in an emergency, you may be
given a neck line. This is where a small tube is inserted into a
vein in your neck.

17. The haemodialysis process
• Most people need three sessions of haemodialysis a week, with each session
lasting around four hours. This can be done in hospital
• Two thin needles will be inserted into AV fistula or graft and taped into
place. One needle will slowly remove blood and transfer it to a machine
called a dialyser or dialysis machine.
• The dialysis machine is made up of a series of membranes that act as filters
and a special liquid called dialysate.
• The membranes filter waste products from blood, which are passed into the
dialysate fluid. The used dialysate fluid is pumped out of the dialyser and
the filtered blood is passed back into your body through the second needle.
• During your dialysis sessions, you will sit or lie on a couch, recliner or bed.
You will be able to read, listen to music, use your mobile phone or sleep.
• Haemodialysis isn't painful, but some people feel a bit sick and dizzy, and
may have muscle cramps during the procedure. This is caused by the rapid
changes in blood fluid levels that occur during the treatment.
• After the dialysis session, the needles are removed and a plaster is applied
to prevent bleeding. If you were treated in hospital, you can usually go
home shortly afterwards.

18. Peritoneal dialysis
• There are two main types of peritoneal dialysis:
1- continuous ambulatory peritoneal dialysis
(CAPD) – where blood is filtered several times
during the day
2- automated peritoneal dialysis (APD) – where a
machine helps filter blood during the night as
patient sleep
• Both treatments can be done at home once
patient trained to carry them out himself.

19. Preparing for treatment
• Before have CAPD or APD, an opening will need to
be made in abdomen. This will allow the dialysis
fluid (dialysate) to be pumped into the space inside
your abdomen (the peritoneal cavity).
• An incision is usually made just below belly button.
A thin tube called a catheter is inserted into the
incision and the opening will normally be left to heal
for a few weeks before treatment starts.
• The catheter is permanently attached to abdomen,
which some people find difficult.

20. Dialysis and pregnancy
• Becoming pregnant while on dialysis can
sometimes be dangerous for the mother and
baby.
• It's possible to have a successful pregnancy while
on dialysis, but will probably need to be
monitored more closely at a dialysis unit and
may need more frequent or longer treatment
sessions.