Urinary System and Elimination

Urinary Elimination

• Urinary elimination is a basic human function.
• It can be compromised by illness or certain procedures.
• Urination involves the bladder, urinary sphincter, and central nervous system (CNS).
• Most people experience a strong urge to urinate when the bladder holds approximately 400-600 milliliters of urine.

Class Objectives

• Reading: Fundamentals of Nursing, P&P, Chapters 46 & 47
• Explain the function and role of urinary system structures in urine formation and elimination. (CO 1)
• Understand factors that commonly impact urinary elimination. (CO 1,7)
• Know common alterations associated with urinary elimination. (CO 8)
• Interpret features of normal and abnormal urine. (CO 2)
• Be familiar with common diagnostic tests of the urinary system. (CO 1,2)
• Know the role of the gastrointestinal organs and their physiological function in digestion and elimination. (CO 1)
• Understand how psychological and physiological factors may alter the elimination process. (CO 4,5)
• Discuss Nursing interventions to promote normal elimination and reduce the issues.

Assigned Reading

• Pages 1255-1273 (This is lab content and does not need to be reviewed for this lecture.)
• Catheter insertion and straight catheter techniques are not required for this lecture.

Urinary Tract Organs

• Urinary tract organs: Kidneys, Ureters, Bladder, Urethra
• Upper urinary tract: Kidneys and Ureters
• Lower urinary tract: Bladder and Urethra

Kidneys

• Nephrons are the functional units of the kidneys.
• Glomerulus act as a filter.
• Large proteins do not normally filter through the glomerulus.
• 99% of glomerular filtrate is reabsorbed.
• 1% of glomerular filtrate is excreted as waste.
• The kidneys play an essential role in erythropoietin production which stimulates red blood cell production and maturation in the bone marrow.
• Decreased blood supply triggers renin release, an enzyme that converts angiotensinogen into angiotensin I.
• Angiotensin I is converted to angiotensin II in the lungs.
• Angiotensin II stimulates aldosterone release, which increases water retention and increases blood pressure.

Ureters

• Function: Carry urine to the bladder.
• Urine is sterile.
• Obstruction (e.g., stone) can cause backflow, causing distention (hydronephrosis).

Bladder

• Distensible muscular organ that acts as a reservoir.
• Expands as it fills.
• Pressure is low during filling to prevent backflow and risk of infection.

Urethra

• Urine travels from bladder through the urethra.
• Female urethra is 3-4 cm (1-1.5 inches) – shorter length increases UTI risk.
• Male urethra is 18-20 cm (7-8 inches)

Nurse's Role in Urinary Elimination Management

• Urinary elimination is a basic human function.
• It can be compromised by illness and procedures.
• Most experience a strong urge to urinate when the bladder holds 400-600 milliliters of urine.
• Nurse's role: Assess urinary tract functions and support bladder emptying.
• Minimum hourly urinary output for an adult: Not specified.

Common Urinary Elimination Problems

• Urinary Retention: Accumulation of urine due to the inability of the bladder to empty. Check for post-void residual with bladder scanner.
• Urinary Tract Infection (UTI): Characterized by location (upper-kidney, lower-bladder or urethra). Bacteria are a primary cause of UTIs. E. coli is a common bacterial cause for UTIs.

UTI's (Urinary Tract Infections)

• What causes UTIs? CAUTIs, E. coli
• Who is at risk for UTIs? Elderly persons with atypical presentations, can have nonspecific symptoms, such as delirium, confusion, fatigue, loss of appetite, decline in function, incontinence, falls, temperature.

Urinary Incontinence

• Involuntary loss of urine. Common in older adults and elderly.
• Types of incontinence: transient, functional, overflow, stress, urge/urgency, reflex.

Urinary Catheterization

• When should a catheter be used?
• Minimize risk of infection: CDC infection control guidelines.
• More about healthcare associated infections (HAIs): CDC HAIS.

Urinary Catheterization Types

• Indwelling catheter (Foley): Balloon filled with water keeps one end inside the bladder.
• External female catheter (PureWick): (Video reference provided)
• Intermittent catheters (Straight catheters): Can be used several times a day at scheduled times or when the bladder feels full.
• Suprapubic catheter: Inserted through an incision in the lower abdomen; less risk of infection.
• Condom catheter: An option for some men.

Urinary Catheters

• Catheter changes every 4-6 weeks for long-term use.
• Closed drainage system.
• Catheter irrigations and installations.
• Acetic acid used to cleanse and irrigate inside the bladder.
• Continuous bladder irrigation: Flushes the bladder with normal saline to remove clots from bleeding during or after surgery.

Potential Complications of Urinary Catheterization

• Infection: Most common problem; bacteria from catheter can cause infection.
• Cues for monitoring infection: See page 19 for details.
• Other complications: Leaks, bladder spasms, pain, bladder stones/renal calculus, injury to urethra, kidney damage (with long-term use).

Nursing Measures to Prevent CAUTI

• The Joint Commission- National Patient Safety Goals (NPSG) - prevent inappropriate short-term catheter use, and timely removal of urinary catheters.
• Appropriate sterile technique during placement.
• Meticulous catheter care.

Urinary Diversions

• Types of diversions: temporary or permanent, continent or incontinent.
• Continent urinary reservoir: Catheter inserted into stoma to empty urine from pouch; requires catheterization 4-6 times a day.
• Orthotopic neobladder: Ileal pouch replaces the bladder in the same anatomical position; allows voiding through the urethra.
• Incontinent urinary diversion (Ureterostomy/Ileal conduit): Ureters come out the abdominal wall; no sensation of voiding. Nephrostomy tubes (posterior): Small tubes tunneled through the skin are used to drain the renal pelvis when the ureter is obstructed.

Knowledge Base

• Infection control and hygiene: Use infection control principles to help prevent the development and spread of UTIs.
• Growth and development (e.g., nocturnal enuresis, pregnancy, normal aging).
• Psychosocial implications (e.g., cultural influences, self-image, body image, sexuality).

Assessment

• Intake and output measurements: What should be included?
• Kidneys: Where are they located? Percuss for flank pain/costovertebral angle tenderness.
• Bladder: Palpate for distention, tenderness, and pain; use bladder scanner if retention is suspected.
• External genitalia and urethral meatus: Inspect for drainage, inflammation, swelling, rash, or lesions.
• Perineal skin: Inspect for erythema, skin erosion, itching, or burning pain.

Common Diagnostic Tests of Urinary System

• Urinalysis: Normal values: pH 4.6-8; Specific gravity 1.005-1.030; Glucose, Ketones, Blood, White Blood Cells (WBCs), Bacteria, Crystals.
• Imaging: Pyelogram, Cystography, CT scan, Ultrasound, Prostate/rectal sonogram, Renal angiogram.

Recognize Features of Normal and Abnormal Urine

• Color: Normal is pale straw to amber; Red, pink, or tea-colored urine is usually abnormal and can be caused by certain medications.
• Clarity: Normally transparent; Cloudy or milky urine can be a sign of infection.
• Odor: Characteristic ammonia smell; can be stronger when urine stands. Foul odor is abnormal.

Nursing Responsibilities

• Provide education about: laboratory procedures, specimen handling, infection control policies, diagnostic evaluations, patient care, and preventing potential complications.
• Diagnostic examinations: Obtaining informed consent, assessing for allergies (iodine or contrast dye), adherence to specific diets (e.g., clear liquids), and monitoring I&O.

Evaluation

• Evaluate patient outcomes through patient's perspective (self-image, social interactions, sexuality, emotional status).

Safety Guidelines

• Follow principles of surgical and medical asepsis as indicated.
• Identify patients at risk for latex or povidone-iodine (Betadine) allergies and provide alternatives like chlorhexidine.

Test your knowledge of the urinary system, including urine production, kidney function, and related health issues like UTIs and proteinuria. Learn about the physiological responses in the urinary system.