genitourinary system Flashcards
review: adequate urinary elimination
essential for body fluid homeostasis - the ability of the body to maintain its internal environment at a “steady state”
kidneys:
responsible for “making” the urine, maintaining this balance of what is taken into the body, what is allowed to remain in the body and what is eliminated from the body
functions of the kidneys (10)
- urine formation
- excretion of waste products
- regulation of electrolytes
- regulation of acid-base balance
- control of water balance
- control of BP
- renal clearance
- regulation of RBC production
- synthesis of vitamin D to active form
- secretion of prostaglandins
3 different phases of urine formation
1) glomerular filtration:
- as blood passes into the glomerulus, water, electrolytes, and other small particles (eg. creatinine, urea nitrogen, glucose) filtered across the glomerular membrane into the bowman’s capsule to start forming urine (referred to as the GFR)
2) tubular reabsorption:
- the reabsorption of most of the filtrate keeps normal urine output at 1-3 L/Day, prevents dehydration (most H2O/electrolyte are reabsorbed, kidneys absorb 220 mg/dL)
3) tubular secretion:
- allows substances to move from the blood into the urine
tubular resportion
- this reabsorption of most of the filtrate keeps normal urine output at 1-3L/day and prevents dehydration
TIP:
- most h2o/electrolytes are reabsorbed, kidneys absorb 220 mg/dL
tubular secretion
- allows substances to move from the blood into the urine
vasopressin (ADH) function
makes DCT and CD permeable to water to maximize reabsorption and produce a concentrated urine (opposite diuresis)
ureters
contraction of smooth muscle in the ureter move urine from the kidney pelvis to the bladder
- stretch receptors in the kidney pelvis regulate this movement
bladder
muscular sac that lies directly behind the pubic bone that stores urine, provides continence, and enables voiding
urethra
eliminates urine from the bladder through the urethral meatus
continence
ability to voluntarily control bladder emptying
- continence during bladder filling through the combination of detrusor muscle relaxation, internal sphincter muscle tone, and external sphincter contraction
micturition (voiding) (what, learned response/controlled by (2))
reflex of autonomic control that triggers contraction of the detrusor muscle (closing the ureter at the UVJ to prevent backflow) at the same time as relaxation of the external sphincter and the muscles of the pelvic floor
- learned response and is controlled by the cerebral cortex and brainstem
age related changes (kidney) (6)
- decreased GFR
- nocturia
- decreased bladder capacity
- weakened urinary sphincters and shortened urethra in women
- tendency to retain urine
- diminished thirst stimulation -> hypernatremia, fluid volume deficit
tip:
- discourage fluid intake at night
- pm lasix?
- perineal care, privacy, dysuria, reconcilitation with meds, confusion, uti, bladder distension
physical assessment kidneys (Gi/GU, skin, resp, cardiac, neuro)
1) GI/GU
- auscultate for renal bruits
2) inspect skin:
- check skin for the presence of any rashes, bruising, or yellowish discoloration; or edema in the pedal, pretibial, sacral or around the eyes
3) respiratory assessment:
- listen for crackles or adventitious sounds
4) cardiac assessment:
- listen for murmurs or rubs
5) neurological assessment:
- assess LOC, alertness, deficits in memory or concentration (build up waste products)
diagnostic labs kidneys (7)
- BUN: effectiveness of urea nitrogen (byproduct of protein breakdown in liver)
- CR: indicator of renal function, muscle/protein breakdown (lvl doesn’t increase unless 50% kidney function lost)
- BUN/CR ratio: kidney r/t or non, cardiac output, blood cell production, trauma, I/O
- osmolarity: overall particle concentration in blood, hydration status
- urine specific gravity: hydration status dependent (increase fluid intake -> decrease USG)
- urinalysis: test urine
- urine culture and sensitivity
tip:
- look at trends
proteinuria (what, levels, increased)
protein is not normally present in the urine
- levels >30 mg/hr or 200 mcg/min are abnormal
- increased membrane permeability is caused by infection, inflammation, or immunologic problems
microalbuminuria (normal levels, higher levels)
normal levels in a freshly voided specimen should range between 2.0 and 20 mg/mmol for men, 2.8 and 28 mg/mmol for women
- higher levels: indicate microalbuminuria, mild/early kidney disease (esp. in patients with diabetes mellitus)
creatinine clearance (calculated, measures, normal)
calculated from serum creatinine, age, weight, urine creatinine, gender, and race within 24 hour urine collection
- calculated measure of GFR and kidney function
- normal creatinine clearance: 107-239 mL/min (men), 87-107 mL/min (women)
tip:
- strict labs (urine collected, placed on ice ASAP)
- depends per hospital policy
glomerular filtration rate (GFR) (what, ______ _______ to measure your level.., calculated from, normal, _______ would occur if..)
measure of how well the kidneys are filtering the waste from the blood
- best test to measure your level of kidney function and determine your stage of kidney disease
- calculated from creatinine, age, body size, gender
- normal GFR averages: 125 mL/min
- if the entire amount of filtrate were excreted as urine, DEATH WOULD OCCUR QUICKLY FROM DEHYDRATION
tip:
- controlled by blood flow/perfusion (BP)
diagnostic tests urine (6)
- bladder scanner: noninvasive (measure urine, PVR)
- radiography of kidneys, ureters and bladder (KUB)
- ultrasound: kidney size, obstruction (stonel tumors)
- CT or MRI
- nuclear renal scan: kidney perfusion
- cystography & cystourethrography: outline bladders contour esp. when full (urine flow detection)
urinary tract infection (what, categorized, lower, upper)
described by their location in the tract
- categorized as uncomplicated or complicated (EXAM) (increased risk for tx. failure, serious outcomes, recent cath, urologic abnormalities, male, DM, neurogenic (loss of control d/t brain/spinal/nerve problem), renal insufficiency)
1) lower urinary tract:
- urethritis: urethral infection
- cystitis: bladder infection
- prostatitis: prostate gland infection
2) upper urinary tract
- pyelonephritis: kidney infection
infectious disorders: lower urinary tract s/sx (9)
- frequency
- urgency
- dysuria
- nocturia
- incontinence
- hematuria, pyruia, bacteruia
- suprapubic tenderness or fullness, back pain
- hesitancy or difficulty in initiating urine stream
- retention, feeling of incomplete bladder emptying
tip:
- R/O sepsis
- N/V/fevers/chills
- frequent falls