Renal Failure Flashcards
Functions of the kidneys
Fluid and electrolyte balance
Excretion of waste
Regulation of BP (RAAS)
RBC production (erythropoietin: stimulates RBC prod)
Vitamin D production
Acid-base balance
3 ways the kidneys control bicarbonate:
- Monitor reabsorption
- Production of new bicarb
- Control acid / bugger (excretion of small amts of hydrogen ions - buffered by phosphates/ammonia)
Term for accumulation of nitrogenous wastes:
Azotemia
What is normal GFR?
80-125 mL/min (180L/day)
How much urine do the kidneys produce every minute?
1 mL/min
What is a normal UOP?
mL/hr and mL/kg of weight
*30-60 mL/hr
Aka *0.5-1 mL/kg
Characteristics of acute kidney injury
Oliguria: scant urine output
Azotemia: accumulation of nitrogenous wastes (BUN/creatinine)
Acid-base disturbances
*What is the best measure of renal function?
BUN
What can cause creatinine to increase?
Reduced renal function
Protein break down (can be skewed by diet)
With chronic kidney disease, how long does it take to start showing symptoms?
Takes 3-6 months for BUN & creatinine to increase
*Slow and insidious onset
Prerenal causes of an AKI
Hypovolemia
Hemodynamic instability
Volume depletion
Hypoperfusion
Vasodilation
Decreased cardiac output
Intrarenal causes of an AKI
Acute Tubular Necrosis (most common):
- Sepsis
- Medications (nephrotoxic agents)
- Prolonged ischemia
- Rhabdomyolysis
Medications that can cause intra-renal AKI
Antibiotics - aminoglycosides
NSAIDs
Contrast Media
Why is contrast media nephrotoxic?
Attaches to RBCs temporarily and needs to be filtered by the kidneys
Need to force fluids before and after
How does rhabdomyolysis cause intra-renal AKI
Massive amts of protein breakdown
Gets filtered out by the kidneys and they can’t tolerate all the little strands of protein
Causes of post-renal AKI
Obstruction of flow:
Stones
BPH
Ligation of ureter (by fibrous band)
Foley obstruction
3 phases of AKI
Initiation/onset
Maintenance/oliguric/anuric
Recovery/diuretic
When does phase 1 of AKI occur?
From the time of the event to signs of decreased renal perfusion
How long does phase 1 of AKI last?
A few hours to 2 days
How do we know a patient is having signs of decreased renal perfusion?
Client will be unable to compensate:
- Body is not able to produce enough urine <30mL/hr
- Will also have risking BUN/creatinine
What is the treatment strategy for a patient in phase 1 of AKI?
Figure out what is causing the problem and treat it (want to try to get them out of phase 1)
- Potentially reversible
- No intrinsic renal damage in this stage
Characteristics of AKI phase 2
BUN and creatinine increase daily
Pt is oliguric - output <400 mL/day
Fluid overload
Electrolyte imbalances
*Acidosis
Treatment strategy for a pt in phase 2 AKI
Dialysis required as immediate as possible
8-14 day duration (GFR = 5-10mL/min)
Complications of phase 2
Uremia (build up of uremic acid)
Hyperkalemia (caused by sodium and water being trapped in vascular space, which leaves potassium trapped in the cells)
Infection
What occurs in phase 3 of DKI?
Return of tubular function
BUN&Creatinine begin returning to normal (takes 4-6 months)
Residual impairment of GFR (regain 70-80%)
Treatment strategy of phase 3 of DKI
Support pt and let nature take its course
What is the most specific diagnostic for renal disease?
24 hour creatinine clearance test
What is the most direct reflection of GFR?
Calculated GFR based off of creatinine clearance test
Is an estimated value
Serum tests that determine if pt has renal disease
Elevated Creatinine
Elevated BUN
BUN:creatinine ratio >20:1
Serum osmolality
Normal range for creatinine
0.5-1.2 mg/dL
What is BUN affected by?
Catabolism
Bleeding
Dehydration
What does the BUN:creatinine ratio indicate?
Shows the probability or renal vs. nonrenal issues
Ex: if ratio is 45:2, something going on, but prob not kidney issue
Gold standard to diagnose kidney failure
CT
What does a CT scan show?
Structures
Accumulation of fluid
Why isn’t a KUB the best diagnostic option?
Shows structures
No contrast, lights not on
Why isn’t IVP the best diagnostic option?
Shows structures, has contrast
But watched on x-ray, doesn’t show us what’s going on
Why isn’t a renal scan the best option for diagnosis?
Good for diagnosing, shows renal uptake of isotopes
But pt has to go to neural medicine and ICU pts can’t leave
What is the 2nd best option for diagnosing? why?
Renal angiography
Shows abnormalities in blood flow, infarction, masses
Allows obstruction to be seen
Why isn’t a renal ultrasounds best for diagnosing?
Can see obstruction and size
But these are done later, after pt is out of ICU
Neurological symptoms of a patient with renal failure
Confusion
Lethargy
Decreased LOC
Stupor
What causes the neurological symptoms of renal failure
Due to build up of ammonia and other toxins
Higher = more neuro symptoms
GI symptoms of renal failure
Nausea
Vomiting
Anorexia
Gastritis
Bleeding
Stomatitis
Uremic halitosis
What causes the GI symptoms of renal failure?
Due to all other body symptoms being unhappy as well, pt just feels bad in general
Bleeding caused by gastric anoxia (which is prerenal)
Uremic halitosis caused by urea
Respiratory symptoms of renal failure
Kussmaul’s respirations
Crackles
Pulmonary edema
What causes the respiratory symptoms of renal failure?
Fluid volume overload (left sided heart failure)
Cardiovascular symptoms of kidney failure
Tachycardia
CHF
Dysrhythmias
Rub
Pericarditis
Increased BP
Edema
What causes the the cardiovascular symptoms of renal failure?
Body compensating to try to hurry and do something like getting fluid to kidneys
Pericarditis caused by pushback of fluid
Integumentary symptoms of renal failure
Dry skin
Pruritus
Edema
Bruising
Pallor
Bronze skin (b/c of uremia plus jaundice)
Uremic frost
Hematological symptoms of renal failure
Anemia
Metabolic acidosis
Increased susceptibility to infection
What causes the anemia with renal failure?
RBC breakdown and RBCs not being produced anymore
What is the first sign of hyperkalemia in a patient with renal failure?
Tall tented T waves
What is the level of potassium when a patient’s ECG shows tall tented T waves?
6-7
Symptoms of hypocalcemia
Decreased excretion of phosphorus and *decreased vit D
Paresthesias
Muscle cramps
Weakness
Fatigue
Seizures
*Hypotension
Prolonged QTI, heart blocks, cardiac arrest
Symptoms of hyperphosphatemia
Numbness
Tingling
Tetany
Symptoms of hypermagnesemia
Diminished neuromuscular transmission with **depressed neuromuscular function
*Reflexes will be diminished
Prolonged PRI, QRS
Bradycardia
AV block
Hypotension
Fluid restriction formula
UOP (from previous 24 hrs) + 600 to 1000 mL (determined by Dr.’s order) = fluids allowed for day
How many mL is 1 lb?
How many mL is 1 kg?
1 lb = 500 mL
1 kg = 1000 mL (1 L)
Care for a pt with excess fluid volume
Fluid restriction
Daily weights
Strict input and output
Vital signs Q2h
Prepare pt for dialysis
ACE inhibitors or ARBs for control of BP
Diuretics (for increased renal blood flow)
How should you prepare a pt for dialysis?
- Prepare the room and make room for the machine
- Bathe the pt and change linens bc won’t be able to get to - pt for 4-6 hr
- Pt may need blood before or after, this is your responsibility
Altered nutrition for renal failure patients
Small feedings (may need enteral feedings)
Oral hygiene
Monitor body weight
Vitamins, minerals, nutritional supplements
How to treat electrical imbalances in patients with renal failure
- Restrict K intake
- Provide Ca (tums) or phos-lo (calcium) to reduce intestinal absorption of phosphate
- Give calcitrol (Rocaltrol) (vitamin D) to increase intestinal absorption of Ca
- Monitor ECG changes
- Seizure precautions
- NaHCO3 for control of acidosis
When treating hyperkalemia, how do you cause the intracellular shift of the potassium?
Glucose and insulin - insulin pushes K out of the cell when it can be flushed out and dextrose is given to provide balance
Alkali (sodium bicarb) - for acidosis but has small shift of potassium, not given alone for potassium, but does have an effect
Albuterol - causes insulin shifting & K+ will shift after that. Not strong enough for activation, will need to give other meds first
What is kayexelate?
Used to reduce body K content
Liquid that looks like a milkshake, can be given PO or PR
Traps K and causes it to be excreted in feces
Function of calcium gluconate
Antagonize cellular membrane effect
No direct effect on K+. Given to normalize electrical charge in heart
Nursing actions for activity intolerance / fatigue
Monitor hematocrit and hemoglobin
Assist with ADLs
Administration of epogen
Prerenal treatments to fix volume issue (including meds)
Prevent/treat the cause:
Fluid/volume replacement
Caution in patients with underlying cardiac disease
Blood transfusion
Positive inotropes (dopamine / dobutamine)
Pressers (Levophed, Neo, Epi)
Antiarrhythmics
Medications that are positive inotropes
Dopamine
Dobutamine
Cardiac dose vs. renal dose of dopamine
Renal: 1 - 3.5 - 4 (just enough to push MAP to 70)
BP: 4.5-10
Risk factor of dopamine
Thrombophlebitis if in peripheral vein
Intrarenal treatment
Hydration
Renal perfusion
Antibiotic regulation
Acetylcysteine (Mucomyst)
Meds given for renal perfusion
Dopamine (renal dose)
Diuretics (furosemide)
Antibiotics used for intrarenal treatment
Myosin’s
Nursing considerations for myocins
Need to monitor blood levels
Peak: drawn after med given
Trough: drawn right before next dose
Postrenal treatment
Alleviate obstruction:
- foley or stent
3 types of dialysis for renal replacement therapy
Hemodialysis
Continuous renal replacement therapy
Peritoneal dialysis
How does dialysis work?
Removal of toxic wastes and excess fluid from the body
What are the two types of hemodialysis?
Diffusion (clearance)
Ultra filtration
What is diffusion (clearance) dialysis?
Removal of toxic wastes (fluid stays)
Usually done for overdoses
What is ultra filtration dialysis?
Removal of excess fluid (does not filter out toxins)
Used for heart failure
What is a K+ bath?
Patients with high K+ use a low K+ dialysate
(K+ 6.8; K+ dialysate 0-) lowers pt’s K+
Indications for dialysis
Fluid overload
Electrolyte imbalances
Acid-base disturbances
Uremia
How is hemodialysis accessed?
Percutaneous catheter (most common in ICU)
When can percutaneous hemodialysis catheters be used?
Need chest x-ray to confirm placement with “ok to use”
Then can be used immediately
Meant to be temporary
Nursing implications for percutaneous catheters
Strict aseptic technique
Inspect daily for signs of infection
Sterile dressing changes (done by dialysis personnel only)
Minimal manipulation of the catheter
Do not use for IV fluids, meds, or lab
Less common hemodialysis access methods that are *Not for immediate use
AV fistulas
AV Grrafts (less common)
*Nursing implications for a fistula/graft dialysis access
Protect the device
*Check for thrill (palpation) / bruit (auscultate) q8h
*Never used for BP, lab, IV access, IM injection
Post signs
No restrictive clothing
Do not sleep on affected side
*Check distal pulse q8h (below device)
*Notify MD if no pulse, bruit, or thrill
Nursing implications for hemodialysis
- Done at bedside in ICU (3-4 hr treatment)
- Pre- and post-dialysis labs and weights
- Monitor for complications
- Monitor labs and report abnormal
- Daily weight
- Withhold dialyzable meds
- Avoid antihypertensive agents several hrs before (may need opinions of other nurse to decide, use nursing judgement)
- Monitor pt frequently post dialysis
Possible complications of hemodialysis
Volume depletion (hypotension)
Dysrhythmias
Cramping
Hypoxemia (kidneys not making RBCs & dialysis breaks RBCs up)
Disequilibrium syndrome (pt fees like they’re floating)
Infection
What is the most effective and most aggressive form of dialysis?
Hemodialysis
What are the advantages and disadvantages of Continuous renal replacement therapy (CRRT)?
Advantages:
- For patients too unstable for hemodialysis
- More gradual solute removal
- *Can be done by staff nurses at the bedside
- Have more control
Disadvantages:
- Pt must be on bedrest and can’t move around
- 1:1 nursing care usually
- Clots easily, need to push heparin and flush frequently
Types of CRRT
Slow continuous ultrafiltration (SCUF)
Continuous venovenous hemofiltration (CVVH)
Continuous venovenous hemodialysis (CVVHD)
Continuous venovenous hemodiafiltration (CVVHDF)
*What is SCUF?
Fluid removal only
What is CVVH?
Fluid removal and removal of some waste products
What is CVVHD
Hemodialysis, but done over 24 hours
What is CVVHDF?
Maximum fluid and maximum waste removed
Possible complications of CRRT?
Electrolyte and acid-base imbalances
Fluid imbalances
Hypotension
Hemorrhage
Infection
Hypothermia
Rupture, leakage, or clotting of filter
Air embolism
Nursing implications for CRRT
Hemodynamics done qh
Assess filtration rate qh & give IVF
Assess hemofilter q2-4h for clotting
Monitor labs
Assess system qh
Assess filtrate for blood
Maintain heparin infusion
Consult dialysis nurse for problems
Sterile technique for any access
What is peritoneal dialysis?
Removal of solutes and fluids using the peritoneal membrane as a filter
Why isn’t PD used in the critical care setting very often?
Less efficient
*High risk of peritonitis
Slow process
How does peritoneal dialysis work?
IV pole raised all the way up to produce enough force for infusion
Fluid dwells in peritoneal cavity for a few hrs
Then drain bag is moved to floor for fluids to be drawn out
Fluids should be a clear gold color
Catheter stays in, just need to clean
Complications of peritoneal dialysis
Poor drainage
Fluid leak around catheter
Discomfort from fluid instillation
Pulmonary complications
*Peritonitis
*Symptoms of peritonitis
Cloudy peritoneal fluid
N/V
Difficulty draining fluid
*Fever
*Chills
*Abdominal pain
