urine notes

Copyright Information

  • Copyright © 2008 Wolters Kluwer Health | Lippincott Williams & Wilkins
  • TEXTBOOK OF BASIC NURSING Chapter 89 Urinary Disorders

Medical Terminology

  • Urethra: urethra
  • Ureter: ureter
  • Vesic: bladder
  • Cyst: sac of fluid
  • Ren: kidney
  • Nephr: kidney
  • Uria, Uro: urine
  • Retro: backwards
  • Calc: stone
  • Lith: stone
  • Dys: bad
  • Tripsy: burst apart, crush
  • Pyleo: renal pelvis
  • Glomerul: glomerulus
  • Hydro: water
  • Trophy: development
  • Strict: to tie or bind
  • Oma: swelling; tumor
  • Mono: one
  • Poly: many
  • Oligo: small, few
  • A: without, not
  • Dia: to separate
  • Lysis: loosening, destruction

Renal System Review – Ch. 27

Function:

  • Waste removal system
      - Maintains composition of blood, tissue, and interstitial fluids; contributor to homeostasis
      - Controls blood volume (through excretion or reabsorption)
      - Regulation of electrolytes

Urology:

  • Study of the urinary system

Components:

  • 2 kidneys, 2 ureters, 1 bladder, 1 urethra

Kidneys

  • Structure:
      - 2 in number, bean-shaped
      - Located retroperitoneal
  • Functionality:
      - A person can survive with only one kidney, if needed
      - Highly vascular
  • Protection:
      - Surrounded by fat pads that cushion and absorb shock
  • Nephrons:
      - Regulate and adjust electrolyte and fluid levels through reabsorption, excretion, addition of buffers
      - Parts:
        - Renal cortex (outer layer) contains Bowman’s capsule, glomerulus, convoluted tubules
        - Renal medulla (middle layer) contains additional renal tubules, Loop of Henle, collecting tubules

Nephrons

  • Functional units of the kidney; primary purpose is to FORM urine.
  • Each glomerulus contains a capillary network, partially enclosed in Bowman’s capsule.
      - Functions:
        - Glomeruli: FILTER blood
        - Bowman’s Capsule: COLLECT filtrate composed of water, salt, glucose, and wastes
  • Convoluted Tubules and Collecting Tubules:
      - Allow filtrate to pass by capillaries for reabsorption of any necessary substances (water, salts, glucose).
      - Influenced by hormones for urine REGULATION or DILUTION.
  • Renal Pyramids and Renal Pelvis:
      - Direct remaining collected urine out of the kidneys into the passageway.

Ureters

  • Carry urine from the kidneys to the urinary bladder via peristalsis of smooth muscles.
  • Very sensitive due to the abundance of sensory nerves.

Bladder

  • Structure:
      - Hollow, muscular sac
      - Acts as a reservoir to hold collected urine until discharge
  • Capacity:
      - Varies by age and individual; stretch reflex usually stimulated by 250-400 ml in adults
      - Capacity can reach more than 1000 ml; large drainage amounts can cause spasms.

Urethra

  • Drains urine from the bladder to the outside of the body.
  • Differences in Males and Females:
      - Shorter and straighter in females, predisposing them to UTIs.
      - Male urethra serves as the route for both urine and sperm; it is surrounded by tissue.

Hormonal Influence on Urinary Function

  • Renin:
      - Acts as a blood pressure regulator; when BP decreases, renin is secreted to cause vasoconstriction, raising BP and stimulating aldosterone secretion.
  • Aldosterone:
      - Promotes Na and H2O retention, increasing blood volume and raising BP.
  • Antidiuretic Hormone:
      - Increases water reabsorption, decreasing urine output and maintaining circulating blood volume.
  • Atrial Natriuretic Peptide:
      - Increases kidney filtration and flow when blood volume increases, enhancing excretion of water and salt to reduce heart workload.
  • Erythropoietin:
      - Regulates red blood cell production in response to low oxygen levels.

Micturition (Voiding)

  • The release of urine from the body.
  • Urinary Incontinence:
      - Involuntary voiding.
  • Stretch Reflex:
      - Data sent to the brain regarding bladder wall distention; the CNS responds by relaxing urethral sphincters.
      - Internal Sphincter: Involuntary; External Sphincter: Voluntary.
  • Potty Training:
      - Can begin as early as 18-24 months, accomplished typically by ages 2-5.

Urine Characteristics

  • Average Excretion: 1000-1500 ml of sterile urine daily by adults.
  • Factors Influencing Excretion:
      - Blood pressure, drugs, fluid intake, perspiration, external temperature, fever, and various disease processes.
  • Physical Characteristics:
      - Color: straw to amber; bloody is abnormal.
      - Clarity: should be clear, not cloudy.
      - Odor: mild and distinct, not foul.
      - Specific Gravity: 1.010-1.025; dehydration indicated by higher gravity.

Aging Effects on the Renal System

  • Aging Changes Include:
      - Reduced filtration, absorption, and secretion ability.
      - Decreased kidney weight and number of nephrons.
      - Thickening of nephron membranes, reduced renal blood flow.
      - Fibrotic bladder lining causing decreased capacity and loss of muscle tone, resulting in residual urine.
      - Weakened pelvic muscles, decreased creatinine clearance, and issues such as cancer or prostatic hypertrophy.

Urinary Tract Overview

Upper Tract:

  • Comprises the kidneys and ureters.
      - Functions to filter metabolic by-products, maintain fluid and electrolyte balance, and transport urine to the lower tract.

Lower Tract:

  • Comprises the bladder and urethra.
      - Storage area until micturition occurs and serves as a reservoir and transport system.

Common Urinary Problems

  • Issues such as infections, incontinence, and damage to lower and upper tracts.
  • Systemic disorders that affect blood flow can impact kidney function (such as hypertension, heart failure, trauma, diabetes mellitus, vascular diseases).
  • Urologist: Physician who treats diseases and disorders of the urinary tract.
  • Nephrologist: Physician specializing in medical aspects of kidney disorders.

Urinalysis (UA)

  • Provides information about kidneys and bladder, indicating whether disease affects kidney function parts, if pathogens are active, or if substances meant for body cells escape into urine.
  • Types of Samples:
      - Random Sample: Any time, non-sterile collection.
      - Clean-Catch: Sterile collection requiring specific instructions (gender-sensitive).
      - 24-Hour Urine Collection: Requires specific collection procedures without contamination.

Routine Urinalysis Tests

  • Tests Include:
      - pH, specific gravity, glucose, ketones, albumin, blood, bilirubin, and other abnormalities (casts, pus, crystals).
  • Urine pH: 4.6 to 8.0; typically more acidic.
  • Specific Gravity: 1.010 to 1.025; normal should show no glucose, ketones, bacteria, albumin, or bilirubin.

Urinary Casts

  • Tiny tube-shaped particles found in urine examined microscopically.
      - Casts may include WBCs, RBCs, kidney cells, or substances like protein or fat.
      - Diagnostic significance varies:
      - Fatty Casts: Associated with lipids in urine, often due to nephrotic syndrome.
      - Granular Casts: Indicative of various kidney diseases.
      - Hyaline Casts: May appear due to dehydration or certain medications.
      - RBC Casts: Suggest bleeding into the kidney, visible in many kidney diseases.
      - Renal Tubular Epithelial Cell Casts: Indicate damage to renal tubule cells.
      - Waxy Casts: Seen in advanced kidney disease or chronic kidney failure.
      - WBC Casts: More common in acute kidney diseases.

Urine Culture

  • Procedure: Obtain clean-catch/midstream or catheterization sample for C&S testing.
  • Client Teaching: Proper cleansing techniques, including for women to separate and clean labia and for men to clean the penis before collection.

Abnormalities Indicated by Urinalysis

  • Abnormal pH: Associated with gout, calculi, infections.
  • Abnormal Specific Gravity: Indicates dehydration, overhydration, electrolyte imbalances, liver disorders, burns.
  • Proteinuria/Albuminuria: Signifies nephritis, calculi, renal circulation problems, infection, trauma, preeclampsia.
  • Glycosuria: Suggests diabetes mellitus, shock, or head injury.
  • Ketonuria: Indicates diabetes mellitus, starvation, or high-protein diets.
  • Bilirubin Presence: Linked to liver dysfunction or biliary obstruction.
  • Hemoglobinuria/Hematuria: Assoc. with trauma, infections, tumors, bleeding disorders, anticoagulant overdose.

Nursing Considerations for Urinalysis

  • Educate patients on proper collection methods to avoid contamination, handle specimens with gloves to prevent exposure to blood-borne pathogens, and ensure urine is tested within one hour or refrigerated.

Renal Function Tests

  • Blood Urea Nitrogen (BUN): Evaluates glomeruli's efficacy in removing urea.
      - Elevated in kidney disease but can also elevate with a high protein diet or dehydration.
  • Serum Creatinine: A principal nitrogenous waste; better indicator of renal function.
      - Levels significantly rise only with over 50% GFR reduction.
  • Creatinine Clearance: Indicator of GFR and renal function; normal GFR >125 ml/min.

Imaging Studies

  • General imaging studies: X-ray (KUB), ultrasound, CT, and MRI.
  • Specialized studies: Intravenous pyelogram (IVP), renogram, and various pyelograms for detailed kidney and urinary tract analysis.

Cystoscopy

  • Allows for viewing inside the bladder with a cystoscope (a device equipped with a mirror and lamp).
  • Used for detecting inflammation, visualization of ureter openings, and obtaining kidney specimens.
  • Conducted under general anesthesia; post-op, patients may have difficulty voiding.

Kidney Biopsy

  • Procedure: Kidney located by imaging, and client is positioned to minimize bleeding post-biopsy.
  • Requires monitoring post-op for bleeding and vital signs.

Urodynamic Tests

  • Assesses detrusor muscle, external sphincter muscle, and pelvic muscle function.
  • Includes the filling phase to gauge sensation and capacity and the emptying phase to assess bladder emptying efficiency.

Urine Volume Assessment

  • Measures whether bladder emptied completely; methods include double voiding and bladder scanning for residual volume.

Cystometrogram (CMG)

  • Measures bladder pressure during filling, requiring catheter insertion to assess bladder function and potential leaks.

Urethral Pressure Profile

  • Assesses smooth muscle action along urethra during bladder filling, identifying muscle activity or dysfunction.

Nursing Diagnosis Related to Urinary Issues

  • Consider risks like infection, fluid volume imbalance, incontinence types, retention, impaired tissue integrity, and pain management.

Nursing Process in Caring for Patients with Urinary Disorders

  • Emphasizes planning effective care pre-operative and post-operative, monitoring complications, managing related symptoms, and the importance of patient education and self-care.

Urinary Incontinence

  • Types include transient, true or total incontinence, stress incontinence, reflex and urge incontinence, and overflow incontinence.

Transient Incontinence

  • Can resolve with diagnosis and treatment of factors like dementia, infections, medications, or mobility issues.

True Incontinence

  • Characterized by continuous leakage due to causes like sphincter injury, neurogenic diseases, or invasive cancers.

Stress Incontinence

  • Occurs from increased intra-abdominal pressure.
  • Affects primarily women, often post-trauma or childbirth.

Urge and Reflex Incontinence

  • Involves urgency and involuntary loss due to bladder spasms.

Overflow Incontinence

  • Results from bladder overdistension due to nerve injury or obstructions.

Treatment for Incontinence

  • Techniques include Kegel exercises, biofeedback, medications, and surgical options.

Cystitis (UTI)

  • Infection of the bladder with common causes including E. coli and Staphylococcus saprophyticus.
  • Symptoms: frequency, urgency, dysuria, hematuria.

Pyelonephritis

  • Inflammation of the renal pelvis and medulla due to bacterial infection, leading to reduced kidney function.

Acute vs. Chronic Pyelonephritis

  • Acute: Treatable with antimicrobials and requires hydration.
  • Chronic: Results from recurrent infections leading to scarring and irreversible damage.

Interstitial Cystitis

  • Chronic bladder inflammation; symptoms include frequent voiding, urgency, and pelvic pain.

Glomerulonephritis

  • Inflammatory disease of glomeruli causing kidney damage.

Acute vs Chronic Glomerulonephritis

  • Acute: Often follows infections and may resolve with treatment.
  • Chronic: Silent progression leading to chronic renal failure and irreversible damage.

Calculi

  • Kidney stones formed through various factors; primary symptom is colic (sharp pain).

Treatment of Calculi

  • Emphasizes hydration and dietary changes; may involve lithotripsy or surgical removal.

Ureteral or Urethral Strictures

  • Result in urinary obstruction; treatment includes dilation or surgical urethrotomy.

Renal Cysts and Tumors

Polycystic Kidney Disease

  • Genetic condition characterized by multiple cysts in kidneys; can lead to chronic kidney disease.

Kidney and Bladder Cancers

  • Signs include hematuria and require various diagnostic tests; treatment often involves surgery and chemotherapy.

Urinary Diversions

  • Types include cutaneous and continent diversions; management of stomas and urinary output is crucial.

Trauma to the Urinary Tract

  • Emphasis on assessing and managing kidney injuries; immediate attention required for severe trauma.

Renal Failure

Types:

  • Acute: sudden loss of renal function.
  • Chronic: gradual damage leading to end-stage renal disease.

Treatment:

  • Dialysis: includes peritoneal and hemodialysis; patient education on diet and fluid restrictions is crucial.

Kidney Transplant

the donor must be compatible to reduce rejection. Nurses must provide education and monitor for complications.