Renal Assessment Flashcards
The upper urinary system consists of…
2 kidneys and 2 ureters
The lower urinary system consists of…
A urinary bladder and a urethra
Flow of urine
Urine is formed in kidneys, drains through ureters, stored in bladder, passes from body through the urethra
The kidneys are the principal organs of the urinary system. The primary functions of the kidneys include…
Regulate volume and composition of ECF
Excrete waste products from body
Control BP, produce erythropoietin, activate Vit D, regulate acid-base balance
Kidneys mactrostructure
Bean-shaped organs Adrenal gland lies on top of each kidney Hilus on medial side -Arteries and nerves enter -Veins and ureters exit
Kidneys mictrostructure
Nephron is functional unit
Tubular system includes
Proximal convoluted tubule
Loop of Henle
Distal convoluted tubule
Collecting tubules
Nephron is composed of
Glomerulus
Bowman’s capsule
Tubular system
What is located in the cortex of the kidney?
Glomerulus
Bowman’s capsule
Proximal tubule
Distal tubule
What is located in the medulla?
Loop of Henle
Collecting tubules
Kidneys blood supply
Renal artery arises from aorta
- divides into smaller branches
- each forms an afferent arteriole
- afferent arteriole divides into capillary network (glomerulus)
Glomerular function: physiology of urine formation
Blood is filtered by hydrostatic pressure
Passes through Bowman’s capsule
Glomerular filtrate passes down tubule (GFR)
GFR
Glomerular filtration rate
Amount of blood filtered each minute by glomeruli
Normal is 125mL/min
Tubular function: physiology of urine formation
Reabsorption
-both active and passive transport mechanisms
Secretion
Proximal convoluted tubules
Reabsorbs 80% of electrolytes
Loop of Henle
Reabsorbs water
Descending loop
Reabsorbs water, some sodium, urea, other solutes
Ascending loop
Reabsobs chloride, sodium
BP regulation with kidneys
Renin is secreted from kidneys in response to decreased renal perfusion, decreased arterial BP, decreased ECF, decreased serum Na+ concentration, and increased urinary Na+ concentration
Renin activates angiotensinogen (from liver) to angiotensin I
Angiotensin I is converted to angiotensin II by ACE
Angiotensin II stimulates the release of aldosterone from adrenal cortex
RBC production with kidneys
Erythropoeitin hormone produced in kidneys and secreted in response to hypoxia and decreased renal blood flow
More about angiotensin II
After aldosterone is released from adrenal cortex, it causes Na+ and water retention, leading to an increased ECF volume.
Also causes increased peripheral vasoconstriction
Release of renin is inhibited by elevated BP
Ureters
Carry urine from renal pelvis to bladder
Join the renal pelvis at the ureteropelvic junction (UPJ)
Join the bladder at the ureterovesical junction (UVL)
Bladder
Serves as reservoir for urine (600-1000 mL)
Trigone
Detrusor
Urination, micturition, voidiong, etc
Detrusor
Bladder muscle
Controls ability to pass urine and contract bladder
Urethra
Extends from bladder neck to external meatus Conduit for urine during voiding Length: -Female: 1-2 in -Male: 8-10 in
Urethrovesical unit
Formed by bladder, urethra, pelvic floor muscles
Voluntary control of this unit is defined as continence
-distention of bladder stimulates stretch receptors
-impulses sent to brain
Size and weight of kidneys decrease 20% - 30% when?
Between ages 30 and 90
When does loss for glomerular function (30%-50%) occur?
By seventh decade
What can accelerate the decrease of renal size with age?
Atherosclerosis
Physiologic changes (gerontologic considerations)
Decreased renal blood flow (results in decreased GFR)
Altered hormonal levels
Loss of elasticity and muscle support
Prostate enlargement
Altered hormonal levels results in
Decreased ability to concentrate urine
Altered excretion of water, sodium, potassium, and acid
Palpation during physical exam
Nonpalpable organs (left kidney rarely palpable)
Urinalysis (urine study)
First morning void
Examine urine within 1 hour
First void of the day more likely to be concentrated and contain abnormal constituents if present
Creatinine Clearance (urine study)
Collect 24-hour urine specimen
Closely approximates GFR
Urodynamics
Measures urinary tract function
Study of the storage of urine within bladder and flow of urine through urinary tract
Creatinine and BUN levels
Primarily used for kidney function
Checked before contrast dye studies done to make sure kidneys are healthy enough for study
Anasacara
Generalized, overall edema due to kidneys
Protein in urine…
small protein ok, lots of urine is BAD
Midstream catch
Clean perineal area (labia minora and labia majora for females; around the meatus of the penis in males)
Begin voiding
Mid void, place clean specimen container in line of urine stream
DO NOT TOUCH THE OPENING TO CONTAINER WITH ANYTHING ELSE
