Anatomy & Physiology MATCHING §Let’s test our ?PRIOR? Knowledge of the renal system. §http://www.freenursetutor.com/urinary/flash cards-matching-urinary-system.htmlhttp://www.freenursetutor.com/urinary/flash cards-matching-urinary-system.html
Nephron Function §Functional unit of kidney §1 million per kidney §1200 ml blood pass through the kidney/min §Wastes cannot be excreted as solids; must be excreted in solution §Normal urine production = 1 ml / minute §Kidneys must produce 30 ml/hr minimum
Critical Thinking §A client in hemorrhagic shock may proceed quickly into concomitant renal failure. Why? Glomerular capillary blood pressure is the driving force of glomerular filtration. If blood pressure is not maintained, there is not enough osmotic gradient to sustain filtration.
Nephron Function §Blood filtered through glomerulus §this filtrate moves into Bowman’s capsules §proceeds into proximal tubule where water /electrolytes/glucose & protein are reabsorbed §Loop of Henley – water and solutes such as Na & Cl, are reabsorbed (urine becomes more concentrated) §distal convoluted tubules allows for water and NA reabsorbtion. Controlled reabsorption (by ADH antidiuretic hormone) regulates F/E balance…..collecting duct
Act of Micturition §Urine moves from the kidneys through ureters via peristaltic waves into bladder. §Bladder fills & detrusor muscles sense pressure §Structures and functions for voluntary control of voiding: -External sphincter- restrain or interrupt act -Conscious brain- starts act -Intact spinal cord- needed or else message from the brain is not received.
Hmmm…. §Why are UTIs more common in women than in men? Urethra in women = 1.5 to 2.5 inches Urethra in men = 6 – 8 inches
Alterations in Urinary Function §Incontinence- brain is not receiving impulse or loss of external sphincter control §Retention- distended bladder due to nerve impulses not perceived or muscles unable to function
Characteristics of Urine §Amount 1200 ml/day average §Color §Odor See Next Slide §pH 4.6 – 8.0 §Turbidity §Specific gravity 1.010 – 1.025 §Constituents
Get a partner… AND §Describe to them what normal urine smells like. Eau D’ Asparagus? Asparagus contains a sulfur compound called mercaptan. (It's also found in rotten eggs, onions, garlic, and in the secretions of skunks.) When your digestive tract breaks down this substance, by-products are released that cause the funny scent. Ammonia? Concentrated urine d/t lack of adequate water intact OR Presence of bacteria in urine OR Standing urine (urea converts to ammonia when exposed to oxygen) Sweet? Uncontrolled Diabetes Musty? Liver Disease
Factors That Affect Voiding §Food/fluid intake + loss §Developmental factors See Next Slide §Stress §Activity/Muscle tone §Life style §Medications §???
Geriatric Considerations §Decreased ability of kidneys to concentrate urine and decreased bladder capacity = nocturia §Decreased muscle tone of bladder = increased frequency §Decreased bladder contractility & stasis = increased frequency of UTI §Changes in cognition and mobility (in some) = increased incontinence issues
Physical Assessment §Kidneys: §R kidney located 12 rib §L kidney lower §Tenderness during palpation at costoverterbral angle? §Bladder: §Below symphysis pubis §Supine position to examine §Observe-roundness §Palpate-tenderness, how high it distends §Percussion- full bladder dull sound
Assessment: Lab Results §Urinalysis- WBC, RBC, protein, glucose, bacteria = abnormal constituents §BUN (blood urea nitrogen) end product of protein metabolism… 10-20 mg/dL Increased BUN (azotemia) signifies impaired kidney function… affected by diet ( hi protein intake ) and fluids ( dehydration ) Decreased BUN signifies impaired liver function Many drugs elevate BUN (antibiotics, lasix +++)
Assessment: Lab Results §Serum creatinine - by product of muscle metabolism…excreted entirely by kidneys… Normal = 0.5-1.2 mg/dL Increased levels signify renal impairment §BUN: Creatinine ratio- 20:1… when both rise together indicates kidney failure or disease
Interventions for Urinary Incontinence §Bladder training/ Habit training §External urinary device - Condom Catheter §Indwelling catheter-LAST resort
Condom Catheter (Texas Cath ) §Rubber condom placed on penis of incontinent males §Connects to drainage bag to collect urine §Easy to apply and observe §Comfortable §Doesn’t require intubation §Prevents skin irritation from incontinence
Condom Catheter §Check every 2-4 hrs. §Remove and replace every 24 hrs. §Maintain free urinary drainage §Never tape to skin §Leave 1-2 inch space at tip of penis §Secure snuggly but not too tight §Follow manufacturer instructions
Urinary Catheterization Used to: §Keep bladder deflated during surgery §Measure residual urine PVR (post void residual) should be < 50 ml §Relieve retention §Obtain sterile urine specimen May use either: §Straight catheter or indwelling catheter
Indwelling catheter Refer to Lab Worksheet §Catheter inserted into urinary meatus through urethra into bladder to drain urine §Last resort as it introduces microbes into bladder…leading to UTI (urinary tract infection) §Performed using sterile technique...MD order needed §Remains in place via inflated balloon ALSO Suprapubic Catheter – diverts urethra Urologic Stents- temporary in ureters permanent in urethra Ileal Conduit – diversion of ureters to ileum and stoma; requires appliance
Medications Affecting Urinary Elimination §Antibiotics …work against infection Bactrim, Levaquin, Cipro §Urinary antispasmotics …relieve spasms with UTI Ditropan, Pro-Banthine §Diuretics….increase urinary output Lasix, Diuril §Cholinergics…increase muscle tone & function Used for urinary retention, neurogenic bladder Urecholine
Urinary Specimen Collection Refer to Lab Worksheet §Routine urinalysis §Clean-catch/midstream urine §Sterile specimen ( catheterization or from indwelling catheter) §24 hr. urine