STUDY GUIDE ON RENAL
DISORDERS WINTER
• What are the main functions of the kidneys?
• The main functions of the kidney include:
• Urine formation
• Excretion of waste products
• Regulation of electrolytes
• Regulation of acid–base balance
• Control of water balance
• Control of blood pressure
• Renal clearance volume of plasma completely cleared of a
substance by the kidneys per unit time
• Regulation of RBC production
• Synthesis of vitamin D to active form
• Secretion of prostaglandins
• During urine formation, which two substances should be reabsorbed and
not excreted in the urine?
• Glucose
• Protein
• What two major electrolytes do the kidneys help regulate?
• Sodium (Na)
• Potassium (K)
• (also regulates water)
• What is the role of the kidneys in maintaining serum pH through bicarbonate?
• Reabsorb and return - renal tubules reabsorb & will return any
bicarb from urinary filtrate back to body’s circulation
• Excrete or reabsorb acid, synthesize ammonia, excrete
ammonium chloride.
• Generate NEW bicarb -- to replace any lost bicarb, through chemical
variations
• This newly generated bicarbonate is then reabsorbed by the
tubules and returned to the body.
• Explain the renin-angiotensin system in regulating blood pressure, including
the roles of antidiuretic hormone and aldosterone in this system.
Remember RAAS (Renin - Angiotensin - Aldosterone - System)?
• RENIN START converts angiotensinogen to angiotensin I
• Angiotensin I is then converted to angiotensin II
• Angiotensin II causes the blood pressure to increase.
• b/c of poor perfusion or increase in serum osmolality = pituitary
gland stimulates adrenal cortex to secrete ALDOSTERONE
• Aldosterone released = increase in BP
• Feedback Mechanism
• After increase in BP = vasa recta detects this & causes RENIN
STOP
, • If this feedback mechanism FAILS = HTN
• How do the kidneys contribute to RBC production?
• Anemia, arterial hypoxia, inadequate blood flow = DECREASE in O2
• Kidneys detect this decrease in O2
• Kidneys will release erythropoietin
• Erythropoietin will stimulate bone marrow to produce RBC
• RBC carry O2 back to body, increase O2 again
• How do the kidneys contribute to Vitamin D synthesis?
• The kidneys are also responsible for the final conversion of inactive
vitamin D to its active form (1,25-dihydroxycholecalciferol)
• Vitamin D is necessary for maintaining normal calcium balance in the body
Learning Objective #2: Explain the renal system changes and nursing implications for
older people.
• The GFR decreases starting between 35-40 y/o and a yearly decline of
about 1mL/min continues thereafter.
• Older adults are more susceptible to acute and chronic kidney injury due to
the structural and functional changes of the kidney.
Learning Objective #3: Initiate education, preparation, and monitoring for patients
undergoing diagnostic studies, including labs, 24-hour urine collection, any that
use contrast media, and kidney biopsy.
• What are the normal ranges for urine specific gravity, creatinine
clearance, serum creatinine, serum BUN, and GFR?
• Specific Gravity = 1.010 - 1.025
• Creatinine clearance = Measured in mL/min/1.73m²
• Serum Creatinine = 0.6 - 1.2mg/dL
• Serum BUN = 7-18mg/dL; 8 - 20mg/dL in patients over 60.
• GFR = 90 - 120mL/min/1.73²; older people will have lower GFR levels.
• What is the significance of abnormal values of urine specific gravity,
creatinine clearance, serum creatinine, BUN, and GFR in kidney disorders?
• Specific gravity: 1.010 - 1.025
• Disorders or conditions that cause decreased urine-specific gravity
include diabetes insipidus, glomerulonephritis, and severe renal
damage. Those that can cause increased specific gravity include
diabetes, nephritis, and fluid deficit.
• Creatinine Clearance: Measured in mL/min/1.73m²
• a decrease in glomerular filtration rate is a sign of impaired kidney
function.
• Serum Creatinine: 0.6 - 1.2mg/dL
• elevated during acute episodes and consistently elevated with chronic
infection
• BUN:7-18mg/dL; 8 - 20mg/dL in patients over 60.
, • High levels can indicate dehydration, Urinary tract obstruction,
Congestive heart failure, shock, burn injuries, stress, heart attack,
gastrointestinal bleeding.
• Low levels may indicate liver disease, malnutrition, overhydration.
• GFR in Kidney Disorders: 90 - 120mL/min/1.73²; older people will have lower
GFR levels.
• Decreases level indicator for glomerulonephritis and end-stage kidney
disease.
• What is the purpose and proper collection steps for a 24-hour urine
collection?
• A 24-hour urine collection is a simple lab test that measures what's in your
urine
• Used to check kidney function
• Collection of urine in a special container over a full 24-hour period
• The container must be kept cool until the urine is returned to the lab.
• Starts after one void (usually first in the morning) - note
time at end of void; urine after this time must be collected
until exactly 24 hours after initial void collection
• Proper storage: in proper container, on ice, in patient bathroom
• Do not urinate directly into the container.
• Ensure midway through collection serum creatinine level
is drawn (if ordered)
• Incomplete collection = underestimation of creatinine
clearance
• What are the pre-, intra-, and post-procedure interventions and
rationales for a patient who will receive intravenous contrast media during a
diagnostic test?
* For some patients, contrast agents are nephrotoxic! Emergency equipment and
medications should be available incase of anaphylactic reaction: epinephrine,
corticosteroids, vasopressors in case of BP drop, oxygen, and airway/suction equipment
IV CONTRAST
• Pre-procedure
• Obtain allergy history
• Allergies to iodine, shellfish, other seafoods
because many contrast agents contain iodine.
• Notify provider if any/suspected allergies
• Obtain health history
• Contrast used with caution in (older) patients
with multiple myeloma, renal impairment,
volume depletion
• Obtain medication history
• Nephrotoxic medications should be discontinued
• Vancomycin, amphotericin B, metformin, NSAIDs
• Use of nonionic low-osmolar contrast media (LOCM) and ionic
high-osmolar contrast media (HOCM) indicated in patients with
renal impairment, etc, to prevent contrast-induced nephropathy
• Check kidney function if at risk
• IV hydration prior to exam
DISORDERS WINTER
• What are the main functions of the kidneys?
• The main functions of the kidney include:
• Urine formation
• Excretion of waste products
• Regulation of electrolytes
• Regulation of acid–base balance
• Control of water balance
• Control of blood pressure
• Renal clearance volume of plasma completely cleared of a
substance by the kidneys per unit time
• Regulation of RBC production
• Synthesis of vitamin D to active form
• Secretion of prostaglandins
• During urine formation, which two substances should be reabsorbed and
not excreted in the urine?
• Glucose
• Protein
• What two major electrolytes do the kidneys help regulate?
• Sodium (Na)
• Potassium (K)
• (also regulates water)
• What is the role of the kidneys in maintaining serum pH through bicarbonate?
• Reabsorb and return - renal tubules reabsorb & will return any
bicarb from urinary filtrate back to body’s circulation
• Excrete or reabsorb acid, synthesize ammonia, excrete
ammonium chloride.
• Generate NEW bicarb -- to replace any lost bicarb, through chemical
variations
• This newly generated bicarbonate is then reabsorbed by the
tubules and returned to the body.
• Explain the renin-angiotensin system in regulating blood pressure, including
the roles of antidiuretic hormone and aldosterone in this system.
Remember RAAS (Renin - Angiotensin - Aldosterone - System)?
• RENIN START converts angiotensinogen to angiotensin I
• Angiotensin I is then converted to angiotensin II
• Angiotensin II causes the blood pressure to increase.
• b/c of poor perfusion or increase in serum osmolality = pituitary
gland stimulates adrenal cortex to secrete ALDOSTERONE
• Aldosterone released = increase in BP
• Feedback Mechanism
• After increase in BP = vasa recta detects this & causes RENIN
STOP
, • If this feedback mechanism FAILS = HTN
• How do the kidneys contribute to RBC production?
• Anemia, arterial hypoxia, inadequate blood flow = DECREASE in O2
• Kidneys detect this decrease in O2
• Kidneys will release erythropoietin
• Erythropoietin will stimulate bone marrow to produce RBC
• RBC carry O2 back to body, increase O2 again
• How do the kidneys contribute to Vitamin D synthesis?
• The kidneys are also responsible for the final conversion of inactive
vitamin D to its active form (1,25-dihydroxycholecalciferol)
• Vitamin D is necessary for maintaining normal calcium balance in the body
Learning Objective #2: Explain the renal system changes and nursing implications for
older people.
• The GFR decreases starting between 35-40 y/o and a yearly decline of
about 1mL/min continues thereafter.
• Older adults are more susceptible to acute and chronic kidney injury due to
the structural and functional changes of the kidney.
Learning Objective #3: Initiate education, preparation, and monitoring for patients
undergoing diagnostic studies, including labs, 24-hour urine collection, any that
use contrast media, and kidney biopsy.
• What are the normal ranges for urine specific gravity, creatinine
clearance, serum creatinine, serum BUN, and GFR?
• Specific Gravity = 1.010 - 1.025
• Creatinine clearance = Measured in mL/min/1.73m²
• Serum Creatinine = 0.6 - 1.2mg/dL
• Serum BUN = 7-18mg/dL; 8 - 20mg/dL in patients over 60.
• GFR = 90 - 120mL/min/1.73²; older people will have lower GFR levels.
• What is the significance of abnormal values of urine specific gravity,
creatinine clearance, serum creatinine, BUN, and GFR in kidney disorders?
• Specific gravity: 1.010 - 1.025
• Disorders or conditions that cause decreased urine-specific gravity
include diabetes insipidus, glomerulonephritis, and severe renal
damage. Those that can cause increased specific gravity include
diabetes, nephritis, and fluid deficit.
• Creatinine Clearance: Measured in mL/min/1.73m²
• a decrease in glomerular filtration rate is a sign of impaired kidney
function.
• Serum Creatinine: 0.6 - 1.2mg/dL
• elevated during acute episodes and consistently elevated with chronic
infection
• BUN:7-18mg/dL; 8 - 20mg/dL in patients over 60.
, • High levels can indicate dehydration, Urinary tract obstruction,
Congestive heart failure, shock, burn injuries, stress, heart attack,
gastrointestinal bleeding.
• Low levels may indicate liver disease, malnutrition, overhydration.
• GFR in Kidney Disorders: 90 - 120mL/min/1.73²; older people will have lower
GFR levels.
• Decreases level indicator for glomerulonephritis and end-stage kidney
disease.
• What is the purpose and proper collection steps for a 24-hour urine
collection?
• A 24-hour urine collection is a simple lab test that measures what's in your
urine
• Used to check kidney function
• Collection of urine in a special container over a full 24-hour period
• The container must be kept cool until the urine is returned to the lab.
• Starts after one void (usually first in the morning) - note
time at end of void; urine after this time must be collected
until exactly 24 hours after initial void collection
• Proper storage: in proper container, on ice, in patient bathroom
• Do not urinate directly into the container.
• Ensure midway through collection serum creatinine level
is drawn (if ordered)
• Incomplete collection = underestimation of creatinine
clearance
• What are the pre-, intra-, and post-procedure interventions and
rationales for a patient who will receive intravenous contrast media during a
diagnostic test?
* For some patients, contrast agents are nephrotoxic! Emergency equipment and
medications should be available incase of anaphylactic reaction: epinephrine,
corticosteroids, vasopressors in case of BP drop, oxygen, and airway/suction equipment
IV CONTRAST
• Pre-procedure
• Obtain allergy history
• Allergies to iodine, shellfish, other seafoods
because many contrast agents contain iodine.
• Notify provider if any/suspected allergies
• Obtain health history
• Contrast used with caution in (older) patients
with multiple myeloma, renal impairment,
volume depletion
• Obtain medication history
• Nephrotoxic medications should be discontinued
• Vancomycin, amphotericin B, metformin, NSAIDs
• Use of nonionic low-osmolar contrast media (LOCM) and ionic
high-osmolar contrast media (HOCM) indicated in patients with
renal impairment, etc, to prevent contrast-induced nephropathy
• Check kidney function if at risk
• IV hydration prior to exam
