Download Assessing Clients with Urinary Elimination Disorders

Assessing Clients with
Urinary Elimination Disorders
Chapter 28
Structures of the Urinary System
 Kidneys - Function
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1. Balance electrolyte and water
2. Excrete waste
3. Regulate acid-base balance
4. Secrete hormones
5. Form urine
6. Regulate blood pressure
Will affect the entire body.
Structures of the Urinary System
 Ureters
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transport urine from the kidneys to the bladder
 Bladder
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storage site for urine
holds 300-500cc
 Urethra
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channels urine to the outside of the body
Kidneys
 Each kidney has 3 regions:
 Cortex- (Outer region) Contains glomeruli which are small
clusters of capillaries. Glomeruli are part of the nephrons which
are the functional units of the kidney
 Each kidney contains 1 million nephrons which process blood to
make urine!!
 Medulla- (inner region) nephrons form the renal pyramids. They
channel urine into branches of the innermost region or the renal
pelvis.
 Pelvis- Urine is channeled from the pelvis through the ureter and
into the bladder for storage.
Formation of Urine
 Glomerular Filtration
 fluids and electrolytes go through a membrane
 Tubular Reabsorption
 nutrients are reabsorbed
 Tubular Secretion
 waste is secreted
 Nephron is functioning unit which functions in
glomerular filtration.
Process of urine formation
 Glomerular Filtration- Blood from the renal artery is filtered in the
glomerulus. The filtered product which contains water, salts,
nutrients and waste products is called the glomerular filtrate.
 Tubular Reabsorption- Nutrients and salts are actively
reabsorbed and transported to the peritubular capillary network
and some water is passively reabsorbed into the peritubular
capillaries
 Tubular Secretion- Some substances are actively secreted from
the peritubular capillaries into the distal tubule for removal from
the body.
Glomerular Filtration
 Passive process where fluids and solutes move from the blood
in the glomerulus into the Bowman’s capsule
 The amount of fluid filtered from the blood into the capsule per
minute is called glomerular filtration rate or GFR.
 GFR is the most accurate indicator of kidney function. What lab
test tells us what GFR is?
 Normal GFR is in adults 120/125 mL per minute.
 What controls GFR?
 -Blood pressure and blood volume.
 A drop in blood pressure and or blood volume will cause the
GFR and urine output to fall. / Renal failure in high risk patients
trauma/ severe blood loss.
Reabsorption and Secretion
 Tubular reabsorption- Healthy kidneys all organic nutrients such
as glucose, and amino acids are reabsorbed.
 Water and electrolyte reabsorption is continuously regulated and
adjusted to maintain homeostasis.
 This all happens in the proximal tubules.
 Tubular Secretion- Excess potassium and waste products such
as hydrogen ion, creatinine and ammonia are eliminate from the
body. This process regulates the acid-base balance in the
body.
Urine Concentration
 Loop of Henle urine is concentrated. And further wastes are
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excreted through reabsorption and secretion..
Antidiuretic hormone- Determines the final concentration or
dilution of the urine.
When ADH is secreted water is reabsorbed in the distal tubule
and collecting duct and urine is more concentrated.
When ADH is not secreted, water cannot be reabsorbed and the
urine is more dilute. What substances cause ADH to be
secreted or not secreted?
Receptors in the hypothalamus detect changes in osmolality
and blood volume, thus stimulating ADH production and release
as needed.
Urine is about 95% water and 5% solutes.
Urine Concentration and
Endocrine Function
 Solutes normally excreted in the urine- Urea, sodium,
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potassium, phosphate, sulfate, creatinine, uric acid, calcium,
magnesium, and bicarbonate.
The kidney also produces renin and erythropoietin and they
activate Vitamin D.
Renin- Is an enzyme made by the juxtaglomerular apparatus in
the kidney. It converts the plasma protein angiotensin to
angiotensin 1. A1 is converted to A2 in the lungs.
Angiotension 2- is a potent vasoconstrictor that raises blood
pressure, it also stimulates the adrenal glands to release
aldosterone which promotes sodium and water retention. Drugs
such as ACE inhibitors work on the Angiotension system to
reduce blood pressure.
The effect of the Angiotensin system is to raise the BP and BV.
Endocrine Function- Kidney
 Erythropoietin- a substance produced by the kidney in response
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to cellular hypoxia. It stimulates the bone marrow to produce
red blood cells.
Vitamin D- Is inactive when it enters the body either through the
diet or by exposure to ultraviolet light. It is activated in two steps
by the liver and then the kidney.
Age Related Changes in the Kidney:
Nephrons are lost with aging, thus kidney mass and GFR are
reduced.
By age 80 GFR may be less than half of what it was at 30.
The kidneys are less able to concentrate urine.
Increased risk for dehydration. Potassium excretion may be
decreased in older, thus electrolyte imbalances are a risk!
Formation of Urine
Assessment of Urinary Function
 Health Assessment Interview
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“Any burning on urination?”
“Any difficulty in starting a stream?”
Bladder control?
Ask about
Pregnancy
Family history of kidney disease
Alcohol and caffeine
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dysuria, nocturia, hematuria, oliguria, polyuria
Physical Assessment
 Inspection
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Skin
Abdomen
Urine
 Percussion
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for CVA tenderness, suprapubic pain, bladder.
Palpation- Kidneys?
Physical Assessment
 Palpation
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bladder
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palpate over the symphysis pubis for distension
Urinalysis - how collected, why
collected?
Characteristics of Normal Urine
 Color - pale to deep yellow, clear
 Odor 
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aromatic
Specific Gravity - 1.001-1.030
pH - 4.5-8.0
Protein - negative to trace
Glucose - negative
Ketones - negative
WBCs 0-5
RBCs 0-5
Casts - negative to occasional
Laboratory Tests
 UA- Urinalysis is a key part of the diagnostic evaluation of the
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urinary system.
Urea- is formed in the metabolism of dietary and body proteins.
Creatinine is produced by muscle cell metabolism.
Both substances are eliminated from the body by the kidneys by
filtration and secretion; neither is reabsorbed, thus BUN and
Serum creatinine levels in the blood are effective indicators of
renal function.
Creatinine Clearance test requires 24 hour urine sampleAnother indicator of GFR./ Blood at the same time.
KUB- Abdominal X-ray evaluate the size, shape and position of
organs in the urinary tract.
IVP-Intravenous pyelography- contrast medium and x-ray to
evaluate the urinary tract.
NCLEX
 Digoxin 0.25mg daily has been prescribed for an 80 yo client.
 The nurse observes closely for:
 A. Evidence of drug excretion without the desired effect
 B. Excretion of the drug unchanged in the urine
 C. Impaired urination due to the effects of the drug
 D. Manifestations of drug toxicity due to impaired excretion
NCLEX
 During the assessment of a client’s renal
system, the nurse is unable to palpate the
kidneys. This finding is indicative of:
 A. inflammation
 B. chronic renal disease
 C. nothing
 D. polycystic kidney disease
NCLEX
 A client is admitted with an infection of the
ureters. The nurse realizes that this infection
could include which of the following structures
of the kidney?
 A. cortex
 B. Medulla
 C. Pelvis
 D. Adrenal glands
NCLEX
 During the assessment of a client with
multiple injuries, the nurse notices a large
hematoma located at the left costovertebral
angle. Which additional body system should
this nurse assess?
 A. gastrointestinal
 B. renal
 C. spinal
 D. respiratory
NCLEX
 A client is experiencing a sudden decrease in
systemic blood pressure. Which of the
following will occur within the kidney to help
control this blood pressure drop?
 A. Juxtaglomerular cells will release renin
 B. GFR will increase
 C. Renal vessels will dilate
 D. Hydrostatic pressure will increase
NCLEX
 A client is voiding large amounts of highly
diluted urine. The nurse realized the dilution
or concentration of urine is determined by
which of the following?
 A. Presence of urea
 B. Quantity of chloride
 C. Patency of the ureters
 D. Action of antidiuretic hormone
NCLEX
 A client experienced a temporary reduction of oxygen
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due to an asthma attack. The nurse realized that this
drop in oxygen level will have which impact on the
client’s renal functioning?
A. nothing
B. stimulate the absorption of calcium and phosphate
C. stimulate bone marrow to produce more red blood
cells
D. produce large amounts of dilute urine