Renal Flashcards
Describe intermittent dialysis.
Water and excess waste poducts are removed from the blood by being pumped by the dialysis machine through a dialyzer.
Blood flows through a semi-permeable membrane made up of a porous and thin sheet of cellulose or other synthetic material.
The size of the porous material allows certain things to flow through (water, urea, CK, and uric acid) while bigger particles (plasma proteins, bacteria, blood cells) can’t pass through the membrane and therefore arent filtered out.
Who receives hemodialysis?
chronic renal failure
AKI which includes: uremia, fluid overload, acidosis, hyperK, drug overdose.
Who can NOT receive hemodialysis?
coagulopathies - the extracorpeal circuit has to be heparinized, worsening the situation.
hypotension, low CO, sensitive to abrupt volume changes.
people with a continued high catabolic state
Describe CRRT.
This is a case where, like hemodialysis, water, electrolytes, and small to medium sized particles are removed from the blood.
CRRT is different from hemodialysis becuase it contains a simultaneous reinfusion of a solution
THIS IS ALSO A CONTINUOUS PROCEDURE
What is the advantage of CRRT?
Fluids can be balanced from hour to hour
this makes it a good option for people at risk for or with hemodynamic instability that need some form of ultrafiltration
What are some indications for CRRT?
people who are hemodynamically unstable or do not tolerate rapid fluid shifts
those who require large amounts of hourly IV fluids or parenteral nutrition
What are some contraindications for CRRT?
When clients become hemodynamically stable or do not require continuous therapy
coagulopathies may inhibit access to circulation
IF CLIENT DOESNT WANT IT DONT DO IT
Describe peritoneal dialysis.
using the same priciple of diffusion as hemodialysis, the peritoneum is the semipermeable membrane that removes fluid through osmosis rather than a pressure differential in hemodialysis.
What are the indications/contraindications for peritoneal dialysis?
initial treatment for renal failure while being evaluated for HD program
treatment of renal failure when access to bloodstream isnt possible or HD isnt available
What are some advantages of peritoneal dialysis over HD?
supplies and equipment are more simple and readily available
less training required
less risk of side effects, (think hemodynamics)
can be done at home
What are some disadvantages of peritoneal dialysis?
takes more time to remove wastes adequately and restore electrolyte balance
repeated treatments may lead to peritonitis
pulmonary congestion and venous stasis may occur as a result of prolonged immobility
With either type of dialysis, there is always a risk of these three things, what are they?
hypovolemia - limit 2-3 sessions per week unless volume overloaded
Hypotension - do not use antihypertensives 4-6 hours prior to dialysis, this can lead to severe hypotension
muscle cramps - diminished intravascular volume and muscle perfusion can lead to cramps
How are muscle cramps related to hemodialysis treated?
lowering infusion rate
hypertonic fluid administration
NS bolus
Mannitol
What are some medications that are commonly dialyzed?
tylenol acyclovir allopurinol lisinopril lithium tobramycin theophylline niroprusside
What are three things that can cause anemia?
erythropoientin dificiency - renal dysfunction causes decreased secretion, normal RBCs made BIGGEST FACTOR
decreased RBC survival time - uremia damages cells (70 day life span instead of 120 days) or dialysis possibly
blood loss from increased bleeding tendency - imaired platelet aggregation and adhesion, and an altered platelet response to factor VII (von-willebrand) PATHO UNKNOWN
What are some skin alterations that can occur with renal failure or AKI?
xerosis - dryness
pruritus - itching
FOR THE TWO ABOVE THINK INFECTION FROM EXCORIATION
pallor - pale
ecchymosis - bruising
purpura - redish purple dots on skin caused from small bleeds underneath.
pale bronze skin discoloration
What are some of the contributing factors to the skin changes in renal failure or AKI?
alterations in iron deficiency anemia - pigmentation changes
deposition of phosphate crystals into the skin cause little bumps
increased vitamin A levels in the epidermis
Describe uremic frost, when would this be seen?
a white powdery substance that is present on the skin due to the crystallization of urea
this is usually seen in highly uremic clients who need dialysis but have it witheld.
What is the most common acid-base imbalance that is seen with renal failure or injury?
metabolic acidosis
can be intensified by DKA, lactic acidosis, or anything that causes high catabolic state
At what GRF might metabolic acidosis start to occur?
<60ml/min/1.73 m^3
Stage 3 CKD
What is the treatment for metabolic acidosis due to AKI or renal failure? When is treatment indicated?
alkaline medications - bicitra, sodium bicarb tabelets,
OR
dialysis
OR BOTH
What is a risk of taking albumin containing phosphate binders as well as bicitra?
albumin toxicity due to the presence of citrate in bicitra which increases the absorption of albumin in the GI tract
phosphate binders are popular for people with CKD due to the inability to excrete phosphate, so absorption is decreased through these.
when is IV sodium bicarb necessary for treatment of metabolic acidosis due to CKD? why?
pH below 7.2 or plasma bicard < 12-14
IV sodium bicarb can cause fluid volume excess, metabolic alkalosis, and hypokalemia
What is the preferred treatment for intractable metabolic acidosis in CKD clients?
dialysis - whihc provides a buffer and removes free hydrogen ions (HD- bicarb, peritoneal - lactate)
Why do you have to be cautious when correcting metabolic acidosis? What labs values should be monitored?
rapid correction may lead to hypoventilation and suppressed respiratory drive, hypocalcemia and tetany due to binding of calcium to albumin and phosphate in alkalotic state,
monitor serum bicarb, pH, Ca, and K
What are some cardiac complications associated with CKD?
dysrhythmias
left ventricular hypertrophy
CAD
cardiomyopathy
CHF
valvular disease
Is there an association between CKD and CVD?
YES, they each cause and exacerbate each other!
CVD causes renal dysfunction
CKD increases risk for CVD
HTN, DM, anemia, HLD, all accelerate renal and cardiovascular dysfunction
