Chapter_029

Chapter 29: Promoting Urinary Elimination

Lesson 29.1 Overview of the Urinary System and Urine Collection

• Objectives:

  • Review the structure and functions of the urinary system.

  • Identify abnormal urine specimen characteristics.

  • Describe nursing measures to promote normal urination.

• Clinical Practice:

  • Assess urinary status of patients.

  • Conduct accurate urine dipstick tests.

  • Teach "clean-catch" (midstream) specimen collection.

  • Assist patients with toileting.

  • Insert indwelling catheters using sterile techniques.

Structure of the Urinary System

Slide 1 of 2

• Kidneys

  • Two bean-shaped organs, 6 cm wide x 12 cm long.

  • Located at lumbar vertebra L1, one on each side of the spine.

  • Each kidney contains approximately 1 million nephrons, the functional units which filter blood.

  • Nephrons:

    • Comprises glomerulus (capillary cluster) in Bowman’s capsule and tubule system.

    • Nephrons enable urine formation and filtration of blood.

Slide 2 of 2

• Ureters

  • Hollow tubes (25-30 cm) carrying urine from kidneys to the bladder.

• Bladder

  • Hollow muscular organ in lower pelvis for urine storage.

• Urethra

  • Conducts urine from bladder to meatus; controlled by urinary sphincter.

  • Meatus: Opening for urine expulsion outside the body.

Function of the Urinary System

Slide 1 of 3

• Kidneys

  • Filter blood via nephrons.

  • Remove metabolic waste and excess water, regulate electrolytes, and maintain acid-base balance.

  • Tubules involved in secretion, excretion, and reabsorption of water, electrolytes, and other substances.

Slide 2 of 3

• Urine Production

  • Kidneys produce approximately 1.5 L of urine daily.

  • Factors influencing urine production include hydration and kidney function.

• Bladder Function:

  • Stores urine and signals fullness; empties when 250-400 mL is present (voluntary).

Slide 3 of 3

• Bladder Capacity

  • Can hold 1000-1800 mL of urine.

  • Average urine output: 1000-1500 mL/day.

  • Urination reflex involves internal sphincter relaxation and voluntary control of the external sphincter.

  • Minimum 600 mL of urine must be excreted daily to eliminate waste.

Factors Interfering with Urinary Elimination

• Total loss of kidney function.

• Decreased kidney perfusion.

• Ureteral obstruction.

• Tumor or traumatic disruption of the bladder.

• Infection or neurologic damage affecting bladder control.

• Impact from prostate surgery.

Changes Occurring with Aging

• Decrease in functioning nephrons and filtration rate.

• Reduced bladder tone leading to nocturia.

• Impaired bladder emptying with increased residual volume.

• Prostate enlargement causing urethral obstruction.

• Incontinence not a normal consequence of aging.

Normal Urinary Elimination Patterns

• Infants: 5 to 40 voids/day.

• Preschool Children: Typically void every 2 hours.

• Adults: 5 to 10 voids/day.

  • Males: 300-500 mL/void; Females: 250 mL/void.

  • Average output: ~30 mL/hr.

Factors Affecting Normal Urination

• Neurological and muscle development.

• Spinal cord integrity alterations.

• Fluid intake, loss through sweating, vomiting, or diarrhea.

• Antidiuretic hormone (ADH) secreted by the pituitary influences fluid retention.

Characteristics of Normal Urine

• Color: Straw-colored or amber.

• Clarity: Transparent or slightly cloudy.

• Odor: Faintly ammonia-like.

• Specific Gravity: 1.010 to 1.030.

• pH: Slightly acidic, between 5.5 to 7.0.

Alterations in Urinary Elimination Patterns

Slide 1 of 3

• Anuria: Less than 100 mL urine in 24 hours.

• Dysuria: Painful urination, potentially from infection/trauma.

• Incontinence: Involuntary release of urine.

Slide 2 of 3

• Nocturia: Waking to urinate more than twice at night.

• Oliguria: Decreased output (less than 400 mL in 24 hours).

• Polyuria: Excessive urination (more than 1500 mL/day).

Slide 3 of 3

• Cystitis: Inflammation of the bladder from irritants or bacteria. Symptoms include frequency, urgency, dysuria, and potentially fever.

Urine Specimens

• Normal Voided Specimen: Send to lab in 5-10 minutes; changes after 15 minutes.

• Midstream (clean-catch) Specimen: Collected mid-void for sterility.

• Indwelling Catheter Specimen: Obtained from an indwelling catheter.

• 24-Hour Specimen: Collected over a full day.

Assessment of Urinary Elimination

• Evaluate usual elimination patterns.

• Document incidences of incontinence and urgency.

• Assess total daily fluid intake and specific symptoms like burning.

Abnormalities Found in Urine

• Glycosuria: Presence of glucose.

• Proteinuria: Presence of protein.

• Hematuria: Presence of blood.

• Pyuria: Presence of pus.

• Ketonuria: Presence of ketones.

Lesson 29.2: Catheterization and Managing Urinary Incontinence

Theory

• Compare purposes of indwelling vs. intermittent catheterization.

• Summarize rationale for continuous bladder irrigation systems.

• Analyze management methods for urinary incontinence.

Clinical Practice

• Insert indwelling catheters with sterile technique.

• Perform catheter care and teach Kegel exercises.

Types of Urinary Catheters and Specimens

• Catheter Types:

  • Robinson, Foley, Suprapubic, Coudé, Alcock, de Pezzer, Malecot, Condom.

• Specimen Types:

  • Routine, Midstream, Indwelling, Sterile, 24-hour, Straining.

Performing Catheterization

• Use sterile equipment and aseptic technique.

• Similar procedures for male and female catheterization, but vary in positioning, draping, and cleansing.

Incontinence

• Loss of bladder control has implications for body image and skin integrity.

• Can be temporary or permanent; may be addressed through surgery or Kegel exercises.

Urinary Diversion Care

• Needed if bladder is removed or bypassed.

• Ureters may be implanted into the abdominal wall (urostomy) or bowel.

• Skin care depends on type of diversion performed.

Documentation

• Record normal voiding patterns and any issues (e.g., dysuria, incontinence).

• Document urine output volume and any bladder irrigations or catheter details.

Questions

Question 1

• Which structures make up the urinary system?

  • Ureters, bladder, kidneys, urethra.

Question 2

• Erin’s patient reports burning during urination; urinalysis shows pyuria.

  • This indicates pus in the urine.

Question 3

• Brenda’s patient with 90 mL output in 3 hours.

  • This indicates a severe decrease in urine output.

Question 4

• All statements about Foley catheter are true except:

  • The balloon is inflated to 15 mL.

Question 5

• A condom catheter is used when a male is incontinent.