Week 13: Chp 62: Renal Replacement Therapies

Question 1

What are Renal Replacement Therapies (RRTs)?

Answer 1

are artificial processes for removing waste and water from the body when the kidneys are no longer functioning adequately

Question 2

Renal Replacement Therapy Therapy ecthniques inclue?

Answer 2

• Intermittent hemodialysis (HD)
• continuous renal replacement therapies (CRRTs)
• peritoneal dialysis (PD)

Question 3

Hemodialysis and Peritoneal dialysis process consists of what?

Answer 3

processes in which blood is separated from a dialysis solution by a semipermeable membrane; hemodialysis uses an artificial membrane; PD uses the peritoneal membrane
-solutes and water move across the membrane by diffusion or movement across a concentration gradient , supported by the addition of dialysate to the circuit, and by filtration, which is the movement of water driven by hydrostatic pressure gradient

Question 4

What is the process of Continuous renal replacement therapies (CRRTs)

Answer 4

process where blood flows through a filter, and solute and fluid removal is accomplished via filtration, diffusion, or convection–the movement of solutes through the membrane via the force of fluid or water movement

Question 5

Dialysis is indicated for what patients?

Answer 5

• AKI (acute kidney injury) and ESRD (end-stage renal disease); characterized by:
• presence of severe fluid and electrolyte imbalances
• elevated serum creatinine
• elevated serum potassium levels
• acidosis
• presence of uremic manifestations
• patients with a GFR of less than 10 mL/min

Question 6

Most common form of renal replacement therapy for ESRD (end-stage renal disease)

Answer 6

-hemodialysis (HD) and peritoneal dialysis (PD)

Question 7

Where can hemodialysis be performed?

Answer 7

in outpatient centers, inpatient hospital settings, and sometimes in home settings

Question 8

Where can peritoneal dialysis be performed?

Answer 8

generally in the home

-can receive while hospitalized or as outpatients

Question 9

Continuous renal replacement therapies (CRRTs) are indicated for?

Answer 9

acutely ill patients
-these therapies manage acid-base balance, electrolyte levels, and fluid balance slowly and continuously in a hemodynamically unstable patient

Question 10

Hemodialysis Vascular Access

Answer 10

3 types of vascular access

• Intravenous vascular access
• arteriovenous (AV) fistula
• arteriovenous (AV) graft

Question 11

Intravenous vascular access

Answer 11

may be secured using a central venous double-lumen catheter in the subclavian or internal jugular vein
-usually used for the short term, such as treating a patient with AKI with intermittent HD or when waiting to secure long term access for HD

Question 12

Arteriovenous (AV) fistula

Answer 12

created by surgical anastomosis of an artery and vein, typically the radial artery and the cephalic vein, in the nondominant arm

• after procedure, the fistula is allowed to mature to become suitable for dialysis; maturing the AV fistula occurs when the low-pressure vein becomes accustomed to the higher pressures generated in the artery which allows adequate blood flow for dialysis
• the “matured” fistula appears large, bulging and tortuous under the skin; can require weeks to months

Question 13

Arteriovenous (AV) graft

Answer 13

created by inserting a prosthetic graft between an artery and vein, in the nondominant arm
-can be used more quickly than the fistula but does not last as long and is more prone to infection (not preferred method)

Question 14

A functional AV fistula and AV graft includes what when assessing?

Answer 14

has a palpable pulsation, a thrill, and a bruit on auscultation

Question 15

Hemodialysis

Answer 15

is a life-sustaining procedure for a patient with AKI or ESRD

• used the process of diffusion and filtration to remove waste products, electrolytes, and excess water from the body
• undergo 3 times a week; 3 to 5 hours for each treatment

Question 16

Process of Hemodialysis

Answer 16

1. Blood is pumped from the body through the vascular access device to a dialyzer
2. in the dialyzer, the blood moves past an artificial semi-permeable membrane
3. a dialysate solution with similar solute concentration as normal extracellular fluid is warmed to body temperature and pumped along the other side of the membrane
4. solute molecule movement across the membrane is determined by a concentration gradient, from an area of higher to lower concentration via diffusion; waste products such as urea and creatinine diffuse across the membrane into the dialysate
5. bicarbonate may be added to the dialysate to make corrections for acidosis if present
6. negative pressure is maintained on the dialysate side to allow excess fluid removal via hydrostatic pressure, a process known as filtration
7. heparin is added to the circuit to prevent clotting
8. saline may be added to help prevent clotting and facilitate flow through the dialyzer
9. the “cleaned” blood is returned via the vascular access device

Question 17

Complications of HD

Answer 17

can occur during, or after dialysis

• hypotension due to the rapid removal of fluid from the vascular compartment or vasodilation; may display light-headedness, nausea, vomiting, seizures, vision changes, and chest pain from cardiac ischemia; decrease the rate of fluid removal and replace fluid IV with normal saline
• muscle cramps, headache, nausea, dizziness, and malaise due to rapid removal of electrolytes and water; reducing the filtration rate or infusing a normal saline bolus
• bleeding because of the altered platelet function associated with uremia and the use of heparin during the procedure
• systemic infection is a concern
• dialysis associated dementia is a progressive, potentially incurable neurological complication associated with long-term dialysis; though to be due to aluminum, which is present in the phosphate binders
• dialysis disequilibrium syndrome
• localized AV fistula or graft complications (infection, clotting, or thrombosis)

Question 18

Peritoneal dialysis

Answer 18

life-sustaining treatment for a patient with ESRD

• offers increased patient control and flexibility with the option of home treatment
• requires a shorter training period for the patient and can be performed independently or by a family member
• involves fewer dietary restrictions and greater mobility
• clearance of metabolic wastes is slower but more continuous
• avoids rapid fluctuations in extracellular fluid composition and associated symptoms
• 3 forms: continuous, automated, and intermittent

Question 19

Peritoneal dialysis (PD) is indicated for who?

Answer 19

patients who desire more control, who have vascular access problems, or who respond poorly to HD with hemodynamic instability
-older patients and ESRD patients with diabetes may be more easily managed with PD

Question 20

The process of peritoneal dialysis (PD)

Answer 20

the highly vascular membrane of the peritoneal cavity is used as the dialyzer layer
-fluid and solute removal occurs via diffusion and filtration
-PD process consists of fill, dwell, and drain phases
>fill phase: room temperature, sterile dialysate is instilled into the peritoneal cavity via a permanent indwelling PD catheter, made of silicone rubber tubing, the fluid remains in the abdomen for a predetermined “dwell” time
-metabolic waste products and excess electrolytes diffuse into the dialysate while it remains in the abdomen; water diffusion is controlled using dextrose in the dialysate as an osmotic gradient; gravity then drains the fluid out of the peritoneal cavity into a sterile bag

Question 21

Contraindications for PD

Answer 21

• history of multiple abdominal surgeries or chronic abdominal conditions such as pancreatitis or diverticulitis
• recurrent abdominal wall or inguinal hernias
• obesity with large abdominal wall
• pre-existing back problems or vertebral disease
• severe chronic obstructive pulmonary disease

Question 22

Complications in PD

Answer 22

• peritonitis and catheter infections
• abdominal pain
• hyperglycemia and increased triglyceride levels
• outflow problems
• respiratory compromise
• protein loss

Question 23

Nursing Interventions: Assessment

Answer 23

• vital signs
• oxygenation/respiratory status
• temperature
• daily weight at the same time everyday
• Lab values
• filtrate appearance
• nutritional intake

Question 24

Assessment: Vital Signs

Answer 24

blood pressure and heart rate are indicators of fluid volume status that are changing during the dialysis procedure
-hypotension may occur with aggressive fluid removal

Question 25

Assessment: oxygenation/respiratory status

Answer 25

decreased oxygenation may occur with fluid volume overload, with decreased respiratory effort, or during dwell time in PD
-abnormal findings such as gallops, murmurs, rales, SOB, and tachypnea can indicate fluid volume overload

Question 26

Assessment: temperature

Answer 26

increased temperature is an indication of infection

-all forms of dialysis increase the risk of infection through the presence of multiple IV lines or a PD catheter

Question 27

Assessment: Filtrate appearance

Answer 27

pink or bloody filtrate in any form of dialysis indicates bleeding
-cloudy filtrate in PD indicates infection

Question 28

Assess: Coagulation studies; hemoglobin/hematocrit

Answer 28

bleeding risk is higher with all forms of dialysis because of the need for heparinization

Question 29

Assess: WBC count

Answer 29

infection is a risk for all forms of dialysis

Question 30

Assess: Electrolyte and renal studies

Answer 30

dialysis produces changes in electrolyte and renal studies, which may require changes in the dialysis procedure or dialysate composition

Question 31

Assess: nutritional intake

Answer 31

sodium and water restriction may be necessary to optimize dialysis
-protein intake may need to be increased because of protein loss during dialysis

Question 32

Nursing assessment With Hemodialysis: frequent assessment of bruit or thrill

Answer 32

a patent AV fistula or graft has a palpable pulsation, a thrill, and a bruit or whooshing sound on auscultations caused by the flow of blood

• a normally functioning graft has a low-pitched bruit
• a turbulent bruit is indicative of increased force, mostly due to stenosis
• absence of thrill or bruit is indicative of a nonfunctional AV fistula or graft

Question 33

Nursing Assessment with Hemodialysis: Neurological assessment

Answer 33

the rapid shift of fluid and substances can create a high osmotic gradient in the brain, resulting in a shift of fluid into the brain causing cerebral edema (dialysis disequilibrium syndrome)
-dialysis related dementia, caused by aluminum in the dialysate or phosphate binders may occur

Question 34

Nursing Assessment with Hemodialysis: Systems assessment post-dialysis

Answer 34

muscle cramps, headache, nausea, dizziness, and malaise are common during and after dialysis as a result of the rapid removal of electrolytes and water

Question 35

Nursing Assessments with Hemodialysis

Answer 35

• frequent assessment of bruit/ thrill
• neurological assessment
• system assessment post-dialysis

Question 36

Nursing Assessment with Peritoneal Dialysis

Answer 36

• abdominal girth; measure the abdominal girth and record in order to make comparisons for future assessments
• monitor outflow; decreased outflow may indicate a kinked or mal-positioned catheter, which may require repositioning of the catheter, turning the patient to the side, or gentle abdominal massage

Question 37

Nursing Actions for hemodialysis

Answer 37

• avoid any procedures, blood draws, IV insertion, or blood pressure readings in the arm with the HD access; can increase the risk of thrombus formation and infection
• hold medications that may be dialyzed out or cause complications during the procedure until after the HD session; some antibiotics or anticonvulsants may be lost in dialysis. Water-soluble vitamins are also lost during dialysis. Anti-hypertensives or vasoactive medications may cause hemodynamic instability during the procedure and should be held as ordered, especially if the patient is known to be hemodynamically unstable during dialysis