Dialysis

1
Dialysis
2
What is Dialysis?

• Dialysis is a type of renal replacement therapy
  which is used to provide artificial replacement
  for lost kidney function due to acute or chronic
  kidney failure
• It is a life support treatment, it does not cure
  acute or chronic renal failure
• May be used for very sick clients who have
  suddenly lost kidney function
• May be used for stable clients who have
  permanently lost kidney function
• Healthy kidneys remove waste products (potassium,
  acid, urea) from the blood and they also remove
  excess fluid in the form of urine
• Dialysis has to duplicate both of these functions
• Dialysis waste removal
• Ultrafiltration fluid removal

3
Principle of Dialysis

• Dialysis works on the principle of diffusion of
  solutes along a concentration gradient across a
  semipermiable membrane
• Blood passes on one side of the semipermeable
  membrane, and a dialysis fluid is passed on the
  other side
• By altering the composition of the dialysis
  fluid, the concentrations of the undesired
  solutes (potassium, urea) in the fluid are low,
  but the desired solutes (sodium) are at their
  natural concentration found in healthy blood

4
Prescription for Dialysis

• A prescription for dialysis is given by a
  physician who specializes in the kidney
  (nephrologist)
• The MD will set various parameters for the
  treatment
• Time and duration of the dialysis sessions
• Size of the dialyzer
• Rate of blood flow

5
2 Main Types of Dialysis

• Hemodialysis
• Peritoneal Dialysis

6
Hemodialysis
Adapted from National Institute of Diabetes and
Digestive and Kidney Diseases. National
Institute of Diabetes and Digestive and Kidney
Diseases. End-stage renal disease choosing a
treatment that's right for you. Available at
http//www.niddk.nih.gov/health/kidney/pubs/esrd/e
srd.htm. Accessed May 10, 2000.
7
What is Hemodialysis (HD)?

• Clients blood is passed through a system of
  tubing (dialysis circuit) via a machine to a
  semipermeable membrane (dialyzer) which has the
  dialysis fluid running on the other side
• The cleansed blood is then returned via the
  circuit back to the body
• The dialysis process is very efficient (much
  higher than in the natural kidneys), which allows
  treatments to take place intermittently (usually
  3 times a week), but fairly large volumes of
  fluid must be removed in a single treatment which
  can be very demanding on a client

8
Side Effects of HD

• The side effects are proportionate to the amount
  of fluid being removed
• Decreased blood pressure
• Fatigue
• Chest pains
• Leg cramps
• Headaches
• Electrolyte imbalance
• NV
• Reaction to the dialyzer
• Air embolism

9
Complications of HD

• Because HD requires access to the circulatory
  system, clients have a portal of entry for
  microbes, which could lead to infection
• The risk of infection depends on the type of
  access used
• Bleeding may also occur at the access site
• Blood clotting was a serious problem in the past,
  but the incidence of this has decreased with the
  routine use of anticoagulants (Heparin is the
  most common)
• Anticoagulants also come with their own risk of
  side effects and complications

10
Rare Complication of HD

• On the rare occasion, a client may have a severe
  anaphylactic reaction
• Sneezing
• Wheezing
• SOB
• Back pain
• Chest pain
• Sudden death
• This can be caused by the sterilant in the
  dialyzer or the material in the membrane itself

11
Three Types of Access for HD

• IV catheter
• Arteriovenous (AV) fistula
• Synthetic graft
• The type of access is influenced by factors such
  as expected time course of the clients renal
  failure and the condition of the clients
  vasculature
• Some clients may have multiple accesses, usually
  because an AV fistula or a graft is maturing and
  an IV catheter is still being used

12
IV Catheter (Central Venous Catheter)

• Consists of a plastic catheter with two lumens
  which is inserted into a large vein (vena cava
  via the internal jugular vein) to allow large
  flows of blood to be withdrawn from the first
  lumen
• The blood goes into the dialysis circuit, and is
  returned to the body via the second lumen
• Non-tunneled
• Tunneled
• This type of access is used for clients who need
  rapid access for immediate dialysis
• Clients who are likely to recover from ARF
• Client with end-stage renal failure
• Clients waiting for other sites to mature
• This type of access is very popular for clients
  because it doesnt involve needles for each
  treatment

13
Complications of an IV Catheter

• Venous Stenosis
• This is the abnormal narrowing of the blood
  vessel
• Because the catheter is a foreign body in the
  vessel, it often provokes an inflammatory
  reaction in the vein wall
• This results in scarring and narrowing of the
  vein, often to the point where the vein occludes

14
AV Fistula

• This access is recognized as the preferred access
  method
• To create a fistula a vascular surgeon joins an
  artery and a vein together
• Since this bypasses the capillaries, blood flows
  at a very high rate through the fistula
• This can be felt by placing a finger over a
  mature fistula (thrill)
• Usually created in the non-dominant hand
• It can be situated on the hand, forearm or the
  elbow
• It will take approximately 4-6 weeks to mature
• During treatment, 2 needles are inserted, one to
  draw blood out of the body and the other to
  return blood to the body

15
Advantages of an AV Fistula

• Decreased infection rate
• Increased blood flow rates, therefore a more
  effective dialysis treatment
• Decreased incidence of thrombosis

16
Complications of an AV Fistula

• If an AV fistula has a very high flow rate and
  the vasculature that supplies the rest of the
  limb is poor, than a steal syndrome can occur
• Blood that enters the limb is drawn into the
  fistula and returned to the general circulation
  without entering the capillaries of the limb
• This results in cool extremities of the limb,
  cramping pains and possible tissue damage
• Long term complications can be the development of
  a bulging in the wall of the vein (aneurysm)
• The vessel wall is weakened by the repeated
  insertion of needles over time
• Can be reduced by careful needling technique

17
AV Graft

• This is much like a fistula, except an artificial
  vessel is used to join the artery and the vein
• Grafts are used when clients own vasculature
  does not permit a fistula
• An AV graft will mature much faster than an AV
  fistula, and it could be ready to use within days
  after formation

18
Complications of an AV Graft

• AV grafts are at high risk for narrowing where
  the graft is sewn to the vein
• As a result clotting or thrombosis may occur
• As a foreign material is being placed in the
  body, there is a greater risk of infection

19
Equipment Needed for HD

• The HD machine performs the function of pumping
  the patient's blood and the dialysate through the
  dialyzer.
• The newest dialysis machines on the market are
  highly computerized and continuously monitor an
  array of safety-critical parameters, including
  blood and dialysate flow rates, blood pressure,
  heart rate, conductivity, pH, etc.
• If any reading is out of normal range, an audible
  alarm will sound to alert the patient-care
  technician who is monitoring the patient.

20
Equipment Water System

• An extensive water purification system is
  absolutely critical for HD
• Since dialysis patients are exposed to vast
  quantities of water, which is mixed with the acid
  bath to form the dialysate, even trace mineral
  contaminants or bacterial endotoxins can filter
  into the patient's blood.
• Because the damaged kidneys are not able to
  perform their intended function of removing
  impurities, ions that are introduced into the
  blood stream via water can build up to hazardous
  levels, causing numerous symptoms including death
  
• For this reason, water used in HD is purified

21
Equipment The Dialyzer

• The dialyzer, or artificial kidney, is the piece
  of equipment that actually filters the blood
• The blood is run through a bundle of very thin
  capillary-like tubes, and the dialysate is pumped
  in a chamber bathing the fibers
• The process mimics the physiology of the
  glomerulus and the rest of the nephron
• Dialyzers come in many different sizes. A larger
  dialyzer will usually translate to an increased
  membrane area, and an increase in the amount of
  undesired solutes removed from the patient's
  blood.
• The nephrologist will prescribe the dialyzer to
  be used depending on the patient
• Dialyzers are not shared between patients in the
  practice of reuse.

22
Peritoneal Dialysis
23
What is Peritoneal Dialysis (PD)?

• Peritoneal dialysis works by using the body's
  peritoneal membrane, which is inside the abdomen,
  as a semi-permeable membrane.
• A specially formulated dialysis fluid is
  instilled around the membrane, using an
  indwelling catheter, then dialysis can occur, by
  diffusion
• Excess fluid can also be removed by osmosis, by
  altering the concentration of glucose in the
  fluid.
• Dialysis fluid is instilled via a peritoneal
  dialysis catheter, which is placed in the
  patient's abdomen, running from the peritoneum
  out to the surface, near the navel
• Peritoneal dialysis is typically done in the
  patient's home and workplace, but can be done
  almost anywhere

24
Advantages of PD

• Can be done at home
• Relatively easy for the client to learn
• Easy to travel with, bags of solution are easy to
  take on holiday
• Fluid balance is usually easier when the client
  is on PD than if the client is on HD

25
Disadvantage of PD

• Requires a degree of motivation and attention to
  cleanliness while performing PD
• There are a number of complications

26
Complications of PD

• Peritoneal dialysis requires access to the
  peritoneum. As this access breaks normal skin
  barriers, and as people with renal failure
  generally have a slightly suppressed immune
  system, infection is a relatively common problem
• Long term peritoneal dialysis can cause changes
  in the peritoneal membrane, causing it to no
  longer act as a dialysis membrane as well as it
  used to.
• This loss of function can manifest as a loss of
  dialysis adequacy, or poorer fluid exchange (also
  known as ultrafiltration failure)
• Fluid may leak into surrounding soft tissue,
  often the scrotum in males
• Hernias are another problem that can occur due to
  the abdominal fluid load

27
Nursing Assessments

• Before client is in the unit, look at the nurses
  notes from the treatment before
• Any problems, will help nurse plan for the
  upcoming treatment
• Look at the client
• Strength
• Gait
• Whether client needs assistance
• Color
• Puffiness
• Could be caused by excess fluid, too much to
  drink, more fluid should be taken off with each
  treatment, changes in voiding pattern (are they
  voiding less than they did last month)

28
Assessments Cont

• Shortness of breath
• Could indicate fluid around the lungs
• Ask about SOB at night (does client have to sleep
  in a sitting position?)
• Ask the client how they are feeling
• The client is usually the best source of
  information
• Clients are in 3 times a week, dialysis nurses
  really get to know their clients
• Evaluate access
• Bruising, swollen, tender
• Bruit listen with the stethoscope for a
  swishing sound of the blood, listen all the way
  up the arm
• Thrill felt with the fingers, tells the nurse
  if the blood is flowing in the fistula (clients
  are told to feel for this at home when a fistula
  is first initiated)

29
Assessments During Treatment

• Ask client how he/she feels
• Dizziness, diaphoretic,
• The machines automatically take BP and HR every
  30 minutes
• Can program the machines to take it at whatever
  interval is necessary (every min, 10 min, 15 min)
• Try to recognize a problem before it starts (ex.
  Hypovolemic shock)
• Assess access site
• Watch trend of BP
• It usually gradually decreases throughout the
  course of the treatment, but look for sudden or
  drastic drops
• Assess access site
• Bleeding, swelling, tenderness

30
Nursing Interventions

• If client comes in with shortness of breath,
  offer O2 which can be kept on for the full
  treatment if necessary
• Comfort
• Clients are sitting in the same chair for up to
  four hours
• Offer extra pillows, some clients have special
  back pillow they leave in the unit
• Ensure TV and audio is working properly

31
Nursing Interventions Cont

• If the blood pressure is dropping too quickly
• Slow or stop fluid removal for a time period
• The machines are constantly being adjusted
  throughout the course of the treatment depending
  on the BP
• If the BP drops suddenly 200-300cc of normal
  saline can be given to balance fluid levels
• Usually, more fluid will be taken off at the
  beginning of the treatment, this will allow the
  client to feel better at the end
• If the client is elderly, fluid removal starts
  slowly to ease them into the treatment

32
Responsibilities of Nursing StaffPrior to
Dialysis

• Ensure client is ready to sit for up to four
  hours
• Encourage client to use washroom before arriving
  to the unit
• Try to avoid laxatives if possible before
  treatment
• Ensure client has eaten meal prior to treatment

33
Responsibilities of Nursing StaffAfter Dialysis

• A dialysis nurse will give unit leader or primary
  nurse a verbal report of treatment
• Any complications during treatment
• Check BP standing and sitting
• Assess access site
• Encourage client to rest
• Avoid treatments or physio for a couple of hours
  if possible
• Watch fluid intake
• Be aware if client is on fluid restriction
• Check thrill and bruit
• Do not take a BP on access arm
• Do not take blood from access arm

34
Dialysis

• Diffusion of solutes through a semi-permeable
  membrane that separates two solutions
• Goals of Dialysis
• Remove excess end products from blood
• Maintain baseline concentration of electrolytes
• Remove excess fluid
• Correct acidosis
• Removal of toxins

35
Types of Dialysis

• 1. Hemodialysis
• 2. Peritoneal Dialysis

36
(No Transcript)
37
Dialysate

• Bath
• Dialysate contains electrolytes in varying
  concentration which prevents complete removal of
  body electrolytes
• Components- Sodium, Calcium, Magnesium,
  Potassium, Chloride, Acetate, Lactate,
  Bicarbonate, Glucose, Dextrose

38
Care of Patients Pre-Hemodialysis

• Medication may be held for 6-12 hours
• Vital signs taken
• Patient teaching- eg. NPO, amount of time the
  dialysis may take
• Therapeutic communication

39
Care of Patients Post-Hemodialysis

• Vitamins may be given post-dialysis.
• Observe access area- hemotoma, bleeding,
  infection.
• Monitor vital signs.
• Monitor vascular response- capillary refill,
  pedal pulse, cyanosis.
• Offer food as per dietary prescription.

40
Patient Education

• Avoid tight clothing around access site
• Check site for adequate blood flow (buzz)
• Watch for signs of infection or bleeding
• Do not allow anyone to draw blood or conduct
  blood pressure from access extremity
• Do not sleep with pressure on extremity
• Avoid use of creams and lotions
• Keep and understand how to use bulldog clamps
  should tubing become disconnected from external
  shunt.