HEMODIALYSIS

DESCRIPTIONS:

Hemodialysis is the diffusion of dissolved particles from one fluid compartment into another across a semipermeable membrane.

The client’s blood flows through one fluid compartment, and the dialysate is in another fluid compartment

FUNCTIONS OF HEMODIALYSIS: Cleanses the blood of accumulated

waste products Removes the by-products of protein

metabolism such as urea, creatinine, and uric acid.

Removes excessive fluids Maintains or restores the buffer

system of the body Maintains or restores electrolyte

levels

PRINCIPLES OF HEMODIALYSIS:

The semipermeable membrane is made of a thin, porous cellophane

The pore size of the membrane allows small particles to pass through, such as urea, creatinine, uric acid and water molecules

Proteins, bacteria, and some blood cells are too large to pass through the membrane

The client’s blood flows into the dialyzer; the movement of substances occurs from the blood to the dialysate

PRINCIPLE OF DIALYSIS

PRINCIPLE OF FILTRATION

PRINCIPLES OF HEMODIALYSIS: Diffusion is the movement of particles

from an area of greater concentration to one of lesser concentration

Osmosis is the movement of fluids across a semipermeable membrane from an area of lesser concentration of particles to an area of greater concentration of particles

Ultrafiltration is the movement of fluid across a semipermeable membrane as a result of an artificially created pressure gradient

DIALYSATE BATH:

A dialysate bath is composed of water and major electrolytes

The dialysate need not be sterile because bacteria are too large to pass through; however, the dialysate must meet specific standards, and water treatment systems are used to ensure a safe water supply

DIALYSATE

DIALYSIS MACHINE

DIALYSIS SET-UP

NURSING INTERVENTIONS:

Monitor vital signs Monitor laboratory values before, during,

and after dialysis Assess the client for fluid overload

before the procedure Assess patency of the blood access

device Weigh the client before and after the

procedure to determine fluid loss

NURSING INTERVENTIONS:

Hold antihypertensives and other medications that can affect the BP before the procedure as prescribed

Hold medications that could be dialyzed off, such as water-soluble vitamins and certain antibiotics

Monitor for shock and hypovolemia during the procedure

Provide adequate nutrition (client may eat before the procedure)

COMPLICATIONS OF HEMODIALYSIS:

1. DISEQUILIBRIUM SYNDROME

Description A rapid change in the composition of the

extracellular fluid occurs during hemodialysis

Solutes are removed from the blood faster than from the cerebrospinal fluid and brain; fluid is pulled into the brain, causing cerebral edema

Assessment Nausea e. Agitation Vomiting f. Confusion Hypertension g. Seizures Restlessness

Nursing Interventions Monitor for signs of disequilibrium

syndrome Notify the physician if signs of

disequilibrium syndrome occur Reduce environmental stimuli Prepare to dialyze the client for a shorter

period at reduced blood flow rates to prevent occurrence

Description An aluminum toxicity occurs as a result

of aluminium in the water sources used in the dialysate and the ingestion of aluminium-containing antacids (phosphate binders)

Assessment a. Progressive neurological impairment b. Speech disturbance c. Dementia d. Muscle incoordination e. Bone pain f. Seizures

2. DIALYSIS ENCEPHALOPATHY

g. Mental cloudiness

Nursing Interventions Monitor for signs of dialysis

encephalopathy Notify the physician if signs of dialysis

encephalopathy occur Administer aluminium-chelating

agents as prescribed so that the aluminium is freed up and dialyzed from the body

OTHER COMPLICATIONS OF HEMODIALYSIS

3. Electrolyte changes 4. Loss of blood

5. Hepatitis 6. Muscle cramping

7. Hypotension and shock 8. Sepsis

AV FISTULA CARE

By:

Joaquin P. Venus III, MD,RN

DIALYSIS EQUIPMENTS

ACCESS FOR HEMODIALYSIS

1. SUBCLAVIAN AND FEMORAL CATHETER

Description A subclavian (subclavian vein) or femoral

(femoral vein) catheter may be inserted for short term or temporary use in acute renal failure

The catheter may be used until a fistula or graft matures or develops or when the client has fistula or graft access failure because of infection or clotting

Nursing Interventions: Assess insertion site for hematoma,

bleeding, dislodging, and infection

Do not use these catheters for any reason other than dialysis

Maintain an occlusive dressing

For Subclavian Catheter: The catheter usually is filled with

heparin and capped to maintain patency between dialysis treatments

The catheter should not be uncapped The catheter may be left in place for

up to 6 weeks if complications do not occur

For Femoral Vein Catheter: The client should not sit up more

than 45 degrees or lean forward, or the catheter may kink and occlude

Assess the extremity for circulation, temperature, and pulses

Prevent pulling or disconnecting of the catheter when giving care

Use an IV infusion pump with microdrip tubing if a heparin infusion through the catheter is prescribed

2. EXTERNAL ARTERIOVENOUS SHUNTDescription Access is formed by the surgical insertion of

two Silastic cannulas into artery and a vein in the forearm or leg to form an external blood path

The cannulas are connected to form a U shape; blood flows from the client’s artery through the shunt into the vein

A tube leading to the membrane compartment of the dialyzer is connected to the arterial cannula

Blood fills the membrane compartment and flows back to the client by way of a tube connected to the venous cannula

When dialysis is complete, the cannulas are clamped and reattached to form their U shape

Advantages The external arteriovenous shunt can be used

immediately following creation No venipuncture is necessary for dialysisDisadvantages External danger of disconnecting or dislodging

the shunt exists Risk of hemorrhage, infection, or clotting

exists Skin erosion around the catheter site can occurNursing Interventions Avoid wetting the shunt A dressing is wrapped completely around the

shunt and kept dry and intact Cannula clamps need to be available at the

client’s bedside Do not take a BP, draw blood, place an IV

line, or administer injections in the shunt extremity

Monitor for hemorrhage, infection, and clotting

Monitor skin integrity around the insertion site

Note that the shunt is patent if it is warm to touch

Auscultate and palpate for a bruit, although a bruit may not be heard and is not always felt with the shunt

Notify the physician immediately if signs of clotting, hemorrhage, or infection occur

Signs of clotting Fold back the dressing to expose the shunt

tubing and assess for signs of clotting Fibrin-white flecks noted in the tubing The separation of serum and cells The absence of a previously heard bruit Coolness of the tubing or extremity Client complaints of tingling sensation

3. INTERNAL ARTERIOVENOUS FISTULA

Description The internal arteriovenous fistula provides the

access of choice for chronic dialysis clients The fistula is created surgically by

anastomosis of a large artery and a large vein in the arm

The flow of arterial blood into the venous system causes the veins to become engorged (matured or developed)

Maturity takes about 1 to 2 weeks and is required before the fistula can be used so that the engorged vein can be punctured with a large-bore needle for the dialysis procedure

Subclavian or femoral catheters, peritoneal dialysis, or an external arteriovenous shunt can be used for dialysis while the fistula is maturing or developing

INTERNAL AV FISTULA (Inside View)

AV FISTULA (Outside View)

Advantages Because the fistula is internal, the danger of clotting

and bleeding is less The fistula can be used indefinitely Fistulas have a decreased incidence of infection No external dressing is required The fistula allows freedom of movement

Disadvantages The fistula cannot be used immediately after

insertion Needle insertions are required for dialysis Infiltration of the needles during dialysis can occur

and cause hematomas An aneurysm can form in the fistula Arterial steal syndrome can develop (too much

blood is diverted to the vein, and arterial perfusion to the hand is compromised)

Congestive heart failure can occur from the increased blood flow in the venous system

5. INTERNAL ARTERIOVENOUS GRAFT

Description The internal graft is used primarily for chronic

dialysis clients who do not have adequate blood vessels for the creation of a fistula

An artificial graft made of Gore-Tex or a bovine (cow) carotid artery is used to create an artificial vein for blood flow

The procedure involves the anastomosis of the graft to the artery, a tunnelling under the skin, and anastomosis to a vein

The graft can be used 2 weeks after insertion Complications of the graft include clotting,

aneurysms and infection

INTERNAL AV GRAFT (Inside view)

Advantages Because the graft is internal, the danger of clotting

and bleeding is less The graft can be used indefinitely The graft has a decrease incidence of infection No external dressing is required The graft allows freedom of movement

Disadvantages The graft cannot be used immediately after

insertion Needle insertions are required for dialysis Infiltration of the needles during dialysis can occur

and cause hematomas An aneurysm can form in the graft Arterial steal syndrome can develop (too much

blood is diverted to the vein, and arterial perfusion to the hand is compromised)

Congestive heart failure can occur from the increased blood flow in the venous system

Nursing Interventions for Arteriovenous Fistula and Arteriovenous Graft

Do not measure a BP, draw blood, place an IV line, or administer injections in the fistula or graft extremity

Monitor for clotting Complaints of tingling or discomfort in the

extremity Inability to palpate a thrill or auscultate a bruit

over the fistula or graft Monitor for arterial steal syndrome Palpate or auscultate for bruit or thrill over the fistula

or graft Palpate pulses below the fistula or graft, and monitor

for hand swelling as an indication of ischemia Note temperature and capillary refill of the

extremity Monitor for infection Monitor lung and heart sounds for signs of CHF Notify the physician immediately if signs of clotting,

infection, or arterial steal syndrome occur

Peritoneal Site Care

By:

Joaquin P. Venus III, MD, RN

DESCRIPTION: 1. The peritoneum is the dialyzing

membrane (semipermeable membrane) and substitutes for kidney function during kidney failure

2. Peritoneal dialysis works on the principles of diffusion and osmosis, and the dialysis occurs via the transfer of fluid and solute from the bloodstream through the peritoneum

3. The peritoneal membrane is large and porous, allowing solutes and fluid to move via an osmotic gradient from an area of higher concentration in the body to an area of lower concentration in the dialyzing fluid

4. The peritoneal cavity is rich in capillaries; therefore it provides a ready access to blood supply

CONTRAINDICATIONS TO PERITONEAL DIALYSIS

Peritonitis Recent abdominal surgery Abdominal adhesions Impending renal transplant

DIALYSATE SOLUTION 1. Solution is sterile 2. Solution contains electrolytes and minerals, a

specific osmolarity, a specific glucose concentration, and other medication additives as prescribed

3. The higher the glucose concentration, the greater the amount of fluid removed during an exchange

4. Increasing the glucose concentration increases the concentration of active particles that cause osmosis and increases the rate of ultrafiltration and the amount of fluid removed

5. If hyperkalemia is not a problem, potassium may be added to each bag of solution

6. Heparin is added to the dialysate solution to prevent clotting of the catheter

7. Prophylactic antibiotics may be added to dialysate to prevent peritonitis

8. Insulin may be added to the dialysate for the client with diabetes mellitus

ACCESS FOR PERITONEAL DIALYSIS

1. DESCRIPTION A surgical insertion of a siliconized rubber

catheter into the abdominal cavity is required to allow infusion of dialysis fluid

The preferred insertion site is 3 to 5 cm below the umbilicus because this area is relatively avascular and has less fascial resistance

The catheters are tunnelled under the skin to stabilize the catheter and reduce the risk of infection

Over a period of 1 to 2 weeks following insertion, an ingrowth of fibroblasts and blood vessels occurs into the cuffs of the catheter, which fix the catheter in place and provide an extra barrier against dialysate leakage and bacterial invasion

SET-UP & PRINCIPLE OF PERITONEAL DIALYSIS

2. TYPES OF PERITONEAL DIALYSIS

A. Continuous Ambulatory Peritoneal Dialysis (CAPD)

Continuous dialysis closely resembles renal function because it is a continuous process

Continuous dialysis does not require a machine for the procedure

Continuous dialysis promotes client independence The client performs self-dialysis 24 hours a day, 7

days a week Usually four dialysis cycles are administered in 24

hours, including an 8-hour dwell time overnight One and a half to 2L of dialysate are instilled into the

abdomen 4 times daily and allowed to dwell as prescribed

The dialysate bag, attached to the catheter, is folded and carried under the client’s clothing until time for outflow

After dwell, the bag is placed lower than the insertion site so that fluid drains by gravity flow

When full, the bag is changed, new dialysate is instilled into the abdomen, and the process continues

SET-UP OF PERITONEAL DIALYSIS

B. Automated Peritoneal Dialysis Automated peritoneal dialysis is similar to continuous

ambulatory peritoneal dialysis in that it is a continuous dialysis process

Automated dialysis requires a peritoneal cycling machine

Automated dialysis can be done as: Intermittent peritoneal dialysis

Dialysis requires a peritoneal cycling machine Dialysis is not a continuous procedure Dialysis is performed for 10 to 14 hours, 3 to 4

times a week Continuous cycling peritoneal dialysis

Dialysis requires a peritoneal cycling machine Dialysis usually consists of three cycles done at night

and one cycle with an 8-hour dwell done in the morning

The sterile catheter system is opened only for the on and off procedures, which reduces the risk of infection

Nightly peritoneal dialysis Dialysis is performed 8 to 12 hours each night with no

daytime exchanges or dwells

PERITONEAL DIALYSIS EQUIPMENTS

PERITONEAL DIALYSIS INFUSIONDescription One infusion (inflow), dwell, and outflow is

considered one exchange Dialysis infusion uses an open system that presents a

risk of infection Inflow: The infusion of 1 to 2 L of dialysate as

prescribed is infused by gravity into the peritoneal space, which usually takes 10 to 20 minutes

Dwell time: The amount of time that the dialysate solution remains in the peritoneal cavity is prescribed by the physician and can last 20 to 30 minutes to 8 or more hours depending on the type of dialysis used

Outflow: Fluid drains out of body by gravity into the drainage bag

Nursing Interventions before Treatment Monitor vital signs Obtain weight Have the client void, if possible Assess electrolyte and glucose levels

Nursing Interventions during Treatment

Monitor vital signs Monitor for signs of infection Monitor for respiratory distress, pain or discomfort Monitor for signs of pulmonary edema Monitor for hypotension and hypertension Monitor for malaise, nausea, vomiting Assess the catheter site dressing for wetness or bleeding Monitor dwell time as prescribed by the physician and

initiate outflow Do not allow dwell time to extend beyond the

physician’s order because this increases the risk fore hyperglycemia

Turn the client from side to side if the outflow is slow to start

Monitor outflow, which should be a continuous stream after the clamp is opened

Monitor outflow for color and clarity Monitor intake and output accurately If outflow is less than inflow, the difference is equal to

the amount absorbed or retained by the client during dialysis and should be counted as intake

COMPLICATIONS OF PERITONEAL DIALYSIS

1. Peritonitis Maintain meticulous sterile technique when

hooking up or clamping off bags and when caring for the catheter insertion site

Follow institutional procedure for hooking up or clamping off bags, which may include scrubbing the connection sites with an antiseptic solution

Monitor temperature closely Monitor for fever, cloudy outflow, and rebound

abdominal tenderness If peritonitis is suspected, obtain a culture of

the outflow to determine the infective organism Administer antibiotics as prescribed

2. Abdominal Pain Pain during inflow is common during the

first few exchanges, is caused by peritoneal irritation, and usually disappears after 1 to 2 weeks of dialysis treatments

The cold temperature of the dialysate aggravates the discomfort, and the dialysate should be warmed before use, only with a special dialysate warmer pad

Place a heating pad on the abdomen during the inflow to relieve discomfort; if a heating pad is used, place it on low setting and monitor the client closely

3. Insufficient Outflow Insufficient outflow may be caused by

catheter migration out of the peritoneal area; if this occurs, the physician must reposition the catheter

Insufficient outflow also can be caused by a full colon

Maintain the drainage bag below the client’s abdomen

Change the client’s outflow position by turning the client on his or her side or by ambulating the client

Check for kinks in the tubing Encourage a high-fiber diet Administer stool softeners as prescribed

4. Leakage around the Catheter site Over a period of 1 to 2 weeks following

insertion of the catheter, an ingrowth of fibroblasts and blood vessels into the cuffs of the catheter occurs that fixes the catheter in place and provides an extra barrier against dialysate leakage and bacterial invasion

It may take up to 2 weeks for the client to tolerate a full 2-L exchange without leaking around the catheter site

5. Characteristics of Outflow During the first or initial exchanges, the

outflow may be bloody; outflow should be clear and colorless thereafter

A brown outflow indicates bowel perforation If the outflow is the same color as urine, this

indicates bladder perforation Cloudy outflow indicates peritonitis

The End