DIALYSIS - Children's Heart Track
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Transcript DIALYSIS - Children's Heart Track
DIALYSIS
Dr. Frank Edwin
CAUSES OF RENAL
FAILURE
Diabetes
Untreated high blood pressure
Inflammation
Heredity
Chronic infection
Obstruction
Accidents
1.Renal Failure Diagnosis
Symptoms: Anorexia, Nausea, Vomiting, Oliguria
• ? Precipitating factors
Signs: Anaemia, Hypertension, Fluid Overload etc
Biochemistry:
– Blood
• Urea >7mmol/l
• Creatinine >120umol/l
• Electrolytes: Rising K+
– Creatinine Clearance (GFR <<120ml/l)
– Urine: Proteinuria
May be Acute or Chronic
Acute – Reversible or Irreversible
2. Treatment Options
No Treatment
Monitoring & Predialysis
– Control symptoms
– Preserve Residual Renal Function
• Control rising BP (Antihypertensives)
• Control Renal Bone Disease (Ca2+, Vit D)
• Prevent/Treat Anaemias (Erythropoietin, Blood)
Dialysis
Renal Transplantation
Dialysis
Definition
Artificial process that partially replaces renal
function
Removes waste products from blood by
diffusion (toxin clearance)
Removes excess water by ultrafiltration
(maintenance of fluid balance)
Wastes and water pass into a special liquid –
dialysis fluid or dialysate
Types
Haemodialysis (HD)
Peritoneal Dialysis (PD)
They work on similar principles: Movement
of solute or water across a semipermeable
membrane (dialysis membrane)
Diffusion
Movement of solute
Across semipermeable membrane
From region of high concentration to one of
low concentration
Ultrafiltration
Made possible by osmosis
Movement of water
Across semipermeable membrane
From low osmolality to high osmolality
Osmolality – number of osmotically active
particles in a unit (litre) of solvent
Selection for HD/PD
Clinical condition
Lifestyle
Patient competence/hygiene (PD - high risk
of infection)
Affordability / Availability
1.
2.
Blood cells are too big to pass through the dialysis membrane,
but body wastes begin to diffuse (pass) into the dialysis solution.
3.
Diffusion is complete. Body wastes have diffused through the membrane,
and now there are equal amounts of waste in both the blood and the
dialysis solution.
The process of ultrafiltration in PD
11.
2
2.
Blood cells are too big to pass through the semi-permeable membrane,
but water in the blood is drawn into the dialysis fluid by the glucose.
3.
Ultrafiltration is complete. Water has been drawn through the peritoneum
by the glucose in the dialysis fluid by the glucose in the dialysis fluid. There is
now extra water in the dialysis
Haemodialysis
Dialysis process occurs outside the body in a
machine
The dialysis membrane is an artificial one:
Dialyser
The dialyser removes the excess fluid and
wastes from the blood and returns the filtered
blood to the body
Haemodialysis needs to be performed three
times a week
Each session lasts 3-6 hrs
Requirements for HD
Good access to patients circulation
Good cardiovascular status (dramatic
changes in BP may occur)
Performing HD
HD may be carried out:
In a HD Unit
At a Minimal Care / Self-Care Centre
At Home
HD Unit
Specially designed Renal Unit within a hospital
Patients must travel to the Unit 3x a week
Patients are unable to move around while on
dialysis; may chat, read, watch TV or eat
Nursing staff prepare equipment, insert the
needles and supervise the sessions
Minimal / Self-Care Dialysis
Patients take a more active role
Patients prepare the dialysis machine, insert
the needles, adjust pump speeds and
machine settings and chart their progress
under the supervision of dialysis staff
Patients must travel to the unit 3x / week
Patients need to be on a fixed schedule
Home Haemodialysis
Use of machines set up at home
Machines have many safety devices inbuilt
Thorough patient training
Requires the help of a partner at home every time
Suitability is assessed by the haemodialysis team
Ideal for patients who value their independence
and need to fit in their treatment around a busy
schedule
HD Access
2 types of access for HD:
– Must provide good flow
– Reliable access
A fistula: arterio-venous (AV)
Vascular Access Catheter
AV Fistula
AV Fistula
Vascular Access Catheter
AV Fistula Access
Matures in about 6 weeks
Ensure good working order
– Avoid tight clothing or wrist watch on fistula arm
– Assess fistula daily; notify immediately if not working
– Avoid BP cuff on fistula arm
– Avoid blood sampling on fistula arm (except daily
HD Rx)
– Avoid sleeping on fistula arm
– Grafts (synthetic) may be used to create an AV fistula
Vascular Access Catheter
Double lumen plastic tube
May be placed in Jugular, Subclavian or Femoral
vein
May be temporary or permanent
Temporary – awaiting fistula or maturation
Permanent – poor vessels for fistula creation e.g.
children and diabetics
Catheters must be kept clean, dry and dressed to
prevent infection
Effects of HD on Lifestyle
Flexibility:
– Difficult to fit in with school, work esp if unit is far from home.
Home HD offers more flexibility
Travel:
– Necessity to book in advance with HD unit of places of travel
Responsibility & Independence:
– Home HD allows the greatest degree of independence
Sexual Activity:
– Anxiety of living with renal failure affects relationship with
partner
Sport & Exercise:
– Can exercise and participate in most sports
Body Image:
– Esp with fistula; patient can be very self conscious about it
Problems with HD
Rapid changes in BP
– fainting, vomiting, cramps, chest pain, irritability, fatigue, temporary loss of
vision
Fluid overload
– esp in between sessions
Fluid restrictions
– more stringent with HD than PD
Hyperkalaemia
– esp in between sessions
Loss of independence
Problems with access
– poor quality, blockage etc. Infection (vascular access catheters)
Pain with needles
Bleeding
– from the fistula during or after dialysis
Infections
– during sessions; exit site infections; blood-borne viruses e.g. Hepatitis, HIV
Peritoneal Dialysis (PD)
Uses natural membrane (peritoneum) for dialysis
Access is by PD catheter, a soft plastic tube
Catheter and dialysis fluid may be hidden under
clothing
Suitability
– Excludes patients with prior peritoneal scarring e.g.
peritonitis, laparotomy
– Excludes patients unable to care for self
Addendum to Principles (PD)
Fluid across the membrane faster than solutes;
therefore longer dwell times are needed for solute
transfer
Protein loss in PD fluid is significant ~ 8-9g/day
Protein loss ↑s during peritonitis
PD patients require adequate daily protein
averaging 1.2 – 1.5g/kg/day
Other substances lost in the dialysate
– Amino acids, water soluble vitamins, some
medications and hormones
Calcium and dextrose are absorbed from the
dialysate fluid into the circulation
Addendum to Principles (PD)
Standard dialysis solution contains:
• Na+ – 132 mEq/l
• Cl- – 96 -102 mEq/l
• Ca2+ – 2.5 – 3.5 mEq/l
• Mg2+ – 0.5 -1.5 mEq/l
Dialysis solution buffer:
– Sodium lactate
– Pure HCo3– HCo3- /Lactate combinations
Lactate is absorbed and converted to HCo3- by
the liver
Dextrose solution strengths: 1.5%, 2.5%, 4.25%
Types
Continuous Ambulatory Peritoneal Dialysis
(CAPD)
Automated peritoneal Dialysis (APD)
CAPD
Dialysis takes place 24hrs a day, 7 days a week
Patient is not attached to a machine for treatment
Exchanges are usually carried out by patient after
training by a CAPD nurse
Most patients need 3-5 exchanges a day i.e.
– 4-6 hour intervals (Dwell time) 30 mins per exchange
May use 2-3 litres of fluid in abdomen
No needles are used
Less dietary and fluid restriction
CAPD Exchange
APD
Uses a home based machine to perform exchanges
Overnight treatment whilst patient sleeps
The APD machine controls the timing of
exchanges, drains the used solution and fills the
peritoneal cavity with new solution
Simple procedure for the patient to perform
Requires about 8-10 hrs
Machines are portable, with in-built safety features
and requires electricity to operate
PD Access
Done under
LA or GA
DIET
Why is diet important?
– Managing the diet can slow renal disease
– The need for dialysis can be delayed
– The diet affects how patients feel
CONTROLLING YOUR
DIET
Foods to control are those containing:
Protein
Potassium
Sodium
Phosphorous
Fluid
PROTEINS
Animal protein
Dairy (milk, cheese)
Meat (steak, pork)
Poultry (chicken, turkey)
Eggs
Plant protein
Vegetables
Breads
Cereals
MAJOR SOURCES
OF POTASSIUM
Milk
Legumes
Potatoes
Nuts
Bananas
Salt substitute
Oranges
Chocolate
Dried Fruit
SODIUM
Regulates blood volume and pressure
Avoid salt
Use Alternate food seasonings: lemon and limes,
spices, seafood seasoning, Italian seasoning,
vinegars, peppers
FLUIDS
Healthy kidneys remove fluids as urine
Check for fluid and sodium retention
Need to restrict fluid intake
PHOSPHOROUS
Phosphorus is a mineral which combines with
calcium to keep bones and teeth strong
Too little calcium and too much phosphorus
Need to control the phosphorus in the diet
Need to take a phosphate binder or a calcium
supplement
VITAMINS
Folic acid
Iron supplements
Do not take OTC’s without consulting the
doctor.
MANAGING YOUR DIET
INDICATORS OF GOOD CONTROL:
Weight loss or gain
Blood pressure
Swelling of hands and feet
Blood samples
LAB MONITORING
Haemoglobin
Sodium
Albumin
Potassium
Calcium
Urea
Phosphorus
Creatinine
GFR
(24 hour urine)
Lifestyle Changes with PD
Flexibility
– Can be performed almost anywhere
– Least impact on work / school life (esp APD)
Travel
– Dialysis supplies can be delivered to most parts of the
world; travel more flexible. APD machines are portable;
will fit into a car boot, can be carried by train/air
Responsibility
– Requires more responsibility from patient but more
independence
Lifestyle Changes with PD
Sports/Exercise
– Most are possible
– Advice on swimming, lifting, contact sports
Sexual Activity
– May affect relations based on patient anxiety
Delivery & Storage of Supplies
– Home delivery and storage
– A month’s supplies – 40 boxes; space to store
– Specially recruited and trained delivery staff
Problems with Treatment
Monotomy of treatment
– The treatment never goes away against days off with HD
Body Image Problems
– Esp with a permanent catheter
– Abdominal stretching
Fluid Overload
– Much less a problem than with HD
Dehydration
– Less common than fluid overload
Abdominal Discomfort
– Bloated feeling
Problems with Treatment
Poor drainage
– Common problem esp with new patients
– Fibrin plug
– Catheter displacement
Leakage
– Fluid may leak around catheter exit site. (May leak
into scrotum)
– Stop PD temporarily
– Resite catheter (use new one)
Infections
– Exit site infections
– Tunnel infection
– peritonitis
Problems with Treatment
Hernia
– Aggravation of pre-existing herniae (repair)
– Evolution of new herniae
Declining effectiveness of the peritoneum
– e.g. repeated infection
– Effect of glucose in the dialysis fluid
Comparison of Dialysis Treatment Options
Home Dialysis
PD
√
Unit HD
×
Home HD
√
Convenient Sessions
√
×
√
Socializn with other CRF pats
×
√
×
Home Equipment/Supplies
√
×
√
Special diet/fluid allowance
√
√
√
Sports/exercises participation
Most
Most
Most
Full day activity -work/school
√
Not alwys
√
Direct assist–partner/family
×
×
√
Travel
√ Delivery of
√ Prior
× Prior
supplies to most
destins easy.
Some notice req
arrangements
must be made
well in advance
arrangements must
be made well in
advance