Renal Diseases Flashcards
What % of cardiac output do the kidneys receive?
15-25%
The kidneys receive approximately ____-____ L/min blood flow.
1-1.5
Blood flow controlled by vascular smooth muscle with changes in vascular resistance. True or false?
true
Surgical sympathetic stimulation increases vascular resistance and increases renal blood flow. True or false?
false
decreases renal blood flow
How does anethesia affect renal blood flow?
decreases renal blood flow by decreasing CO
What are the kidneys responsible for? (7)
maintenance of H20/electrolyte balance
excretion of waste products
secretion of hormones
catabolism of peptide hormones
synthesis of glucose
regulation of arterial pressure
regulation of acid-base balance
What are tests to evaluate renal function? (6)
Glomerular Filtration Rate (GFR)
Blood Urea Nitrogen (BUN)
Serum Creatinine
Creatinine Clearance
BUN/Cr ratio
Urinalysis
pH, specific gravity, glucose, protein
Normal GFR is _____ml/min
125
Indications of decreased GFR do not occur until there is a 20% reduction. True or false?
false
50%
BUN is not elevated until GFR is decreased to almost ____ % of normal.
Normal BUN is: ______mg/dl
75
7-21
What is freely filtered by the kidneys and not reabsorbed?
creatinine
Serum creatinine measurements reflect ______ function.
glomerular
What is the most accurate measure of GFR and what period is it measured over?
creatinine clearance
over 24 hours
Normal creatinine clearance values range is? This is measured over 24 hour period:
90-140 ml/min
What is a hallmark sign of kidney failure?
increased proteins
What does get reabsorbed by the kidneys?
urea
Low tubular flow rates enhance urea reabsorption but do not affect creatinine handling. True or false?
true
What is the normal BUN/Cr ratio?
Abnormal BUN/Cr ratio?
10/1
-30
What may be seen in renal failure or diabetes?
high urine glucose
What is the normal range for urine pH?
4.5 - 8.0
How many H+ do the kidneys remove per day? ___ mEq
60 mEq
KNOW!
Anemia may be present in patients with renal disease because of abnormalities in the production of ________.
erythropoietin
Most patients with chronic renal disease have increased _______ as well as offset ________ balance.
body water
sodium/potassium
What is the deterioration of function over hours to days leading to the inability of the kidneys to excrete waste products and maintain fluid and electrolyte homeostasis?
Acute Renal Failure (ARF)
What patients are highest at risk for acute renal failure?
Elderly
Diabetic
Baseline renal insufficiency
Most commonly will cause a patient to go into acute renal failure:
SEPSIS
What can occur as a result of acute renal failure?
decreased GFR
retention of nitrogenous waste products
What are the 3 types of acute renal failure?
Prerenal (decreased renal blood flow)
Renal (intrinsic)
Postrenal (obstructive)
What are causes of pre-renal ARF? (4)
anything that decreases renal perfusion
Hypotension
Hypovolemia
Congestive heart failure
Pre-renal aortic cross-clamping
What are the causes of renal (intrinsic) ARF?
Intrinsic renal disease
Renal ischemia
Nephrotoxic drugs
What are postrenal/obstructive causes of ARF?
Caused by obstruction of urinary outflow tracts (hydronephrosis)
A diagnosis made with renal ultrasound
ON EXAM
What are risk factors for ARF? (8)
- age
- CHF
- sepsis
- nephrotoxic drugs
- multiple drug transfusions
- hemolysis
- hypotension
- perirenal surgery
What are complications of ARF?
Neurological – confusion, somnolence, seizures
Cardiovascular – systemic hypertension, congestive heart failure, pulmonary edema
Gastrointestinal – anorexia, nausea, vomiting, ileus
Infection – respiratory, urinary tract and sites of indwelling catheters
Most who survive an episode of ARF recover sufficient renal function. True or false?
true
What is hepatorenal syndrome?
functional renal failure that occurs in severe cirrhosis
What is characterized by tight constriction of renal arteries resulting in oliguria and sodium retention and is reversible?
hepatorenal syndrome
Kidneys function normally after liver function is restored.
Deposits of antigen-antibody complexes in the glomeruli cause hematuria, proteinuria, HTN, and increased creatinine characterizes what kidney disease?
Glomerulonephritis
What describes this kidney disease?
- Progressive genetic (autosomal dominant) disease
- Hypertension and proteinuria w/ eventual renal failure
- Treatment options include lifelong dialysis or renal transplant
Polycystic renal disease
What kidney disease is this?
- Atherosclerosis of renal arteries accounts for most cases
- May be unilateral or bilateral
- May be the cause of secondary hypertension
renal artery stenosis
What may be the cause of renal HTN?
aberration of renin-angiotensin-aldosterone system
What is the most common cause of ESRD and results from albuminuria?
diabetic nephropathy
Progressive, irreversible deterioration of renal function that occurs over months or years…
chronic renal failure
As GFR decreases to < ____ mL/min, end stage renal disease results in dialysis or transplant.
25
KNOW
What are causes for chronic renal failure?
glomerulopathy
tubular interstitial disease
hereditary disease
vascular disease
Kidney damage with normal or increased GFR > 90
Stage 1 renal disease
Kidney damage with mildly decreased GFR around 60-89.
Stage 2
Moderately decreased GFR around 30-95
Stage 3 renal disease
Severely decreased GFR 15-29
Stage 4 renal failure
kidney failure or GFR <15 or dialysis
Stage 5
Chronic renal disease is rarely reversible and leads to progressive decline in renal function. True or false?
true
What are some general feelings a person with CRF may have?
fatigue
weakness
malaise
loss of appetite
N/V
What is the primary cause of renal failure and a risk factor for progression of disease?
HTN
What are complications of CRF?
hypervolemia
electrolyte imbalance
metabolic acidosis
anemia
coagulopathy
neuro changes (irritability, seizures, encephalopathy)
cardiovascular changes (CHF, HTN)
What are 2 types of treatment for chronic renal failure?
hemodialysis
peritoneal dialysis
What are the complications of dialysis:
hypotension
infection
peritonitis
What anesthetic drugs are excreteed by the kidneys? (6)
morphine
meperidine
diazepam
H2 receptor anagonists (pepcid)
sevoflurane
muscle relaxants
During preop evaluation, what should you consider with a renal patient?
routine meds
current electrolyte balance
last dialysis
What muscle relaxants are cleared independent of the kidneys?
cisatricurium
atracurium
What is at risk in renal patients–hypo or hypertension?
both
