Renal and Urinary System

Renal System

The urinary system consisting of the kidneys, ureters, bladder, and urethra.

Primary Functions of the Renal System

Filter blood, remove waste products, regulate fluid and electrolyte balance, and maintain homeostasis.

Kidneys

Main organs of the urinary system, located in the flank area between T12 and L3 vertebrae.

Nephron

Functional unit of the kidney responsible for forming urine through filtration, reabsorption, secretion, and excretion.

Glomerulus

Part of the nephron that filters blood, allowing water and small solutes to pass while retaining larger components.

Filtration Problem Indicator

Presence of proteins or blood in urine indicates a problem with filtration.

Reabsorption

Process in renal tubules where essential substances are returned to the bloodstream.

Secretion

Process transferring substances from blood into the nephron to regulate acid-base balance.

Excretion

Final process where urine is eliminated from the body.

Endocrine Functions of the Kidneys

Production of renin for blood pressure regulation, erythropoietin for RBC production, and activation of vitamin D.

Ureters

Tubes carrying urine from the kidneys to the bladder.

Bladder

Muscular organ that stores urine until eliminated.

Detrusor Muscle

Muscle that allows the bladder to expand and contract.

Normal Urine Output

Approximately 30 mL per hour in adults.

Urethra

Tube allowing urine to exit the body.

Continence

Ability to control urination, maintained by the nervous system and pelvic floor muscles.

Age-Related Changes to Kidneys

Decline in kidney function, decrease in nephron number, and reduced blood flow with aging.

Bladder Capacity Changes

Decrease in bladder capacity and weakened muscle tone with age.

Urinary Tract Infections (UTIs)

Infections classified as lower (cystitis) or upper (pyelonephritis) urinary tract infections.

Cystitis

Inflammation of the bladder presenting with dysuria, frequency, urgency, and suprapubic discomfort.

Pyelonephritis

Infection involving the kidneys with symptoms including flank pain and fever.

Common Causative Agents of UTIs

Escherichia coli.

Urinalysis Findings in UTIs

Presence of bacteria, white blood cells, and sometimes blood.

Urethritis

Inflammation of the urethra presenting with localized burning and irritation.

Urinary Calculi

Stones formed from crystallized substances in urine, also known as kidney stones.

Renal Colic

Severe, sharp flank pain caused by moving kidney stones.

Treatment for Kidney Stones

Focuses on pain management, hydration, and possibly lithotripsy or surgical removal.

Benign Prostatic Hyperplasia (BPH)

Enlargement of the prostate gland due to increased cell number, compressing the urethra.

Symptoms of BPH

Include urinary retention, weak stream, hesitancy, dribbling, and nocturia.

Post-TURP Complications

Include risks of bleeding, clot formation, and obstruction of urine flow.

Urinary Retention

Inability to empty the bladder.

Hyperplasia

Increase in cell number causing enlargement of an organ.

Lithotripsy

Procedure to break up kidney stones.

Hydronephrosis

Condition where urine backs up, potentially causing kidney damage.

Creatinine

Most specific indicator of kidney function.

Elevated BUN and Creatinine Levels

Indicates impaired kidney function.

Glomerular Filtration Rate (GFR)

Indicator of kidney performance; decreased GFR indicates worsening kidney function.

Normal Urine Appearance

Pale yellow and clear.

Hematuria

Blood in the urine.

Dysuria

Painful urination.

Frequency

Urinating often in small amounts.

Urgency

Sudden need to urinate.

Clean-catch Midstream Sample

Used to reduce contamination in urinalysis.

Urinary Tract Symptoms

Include dysuria, urgency, frequency, nocturia, flank pain.

Kidney Failure Effects

Waste buildup, fluid overload, electrolyte imbalances, and increased blood pressure.

Urine Culture and Sensitivity Testing

Identifies the specific organism causing infection and appropriate antibiotic treatment.

Narrow Ureter Areas

Common sites for kidney stones to lodge, such as the ureterovesical junction.

Patient Education for UTIs

Includes wiping front to back, staying hydrated, and avoiding irritants.

24-hour Urine Collection

Used to assess kidney function more accurately.

Factors Increasing UTI Risk

Include female anatomy, urinary retention, catheter use, and poor hygiene.

Kegel Exercises

Strengthens perineal muscles to improve continence.

Urine Backing Up Causes

Can lead to hydronephrosis and kidney damage.

Erythropoietin

Hormone produced by kidneys to stimulate red blood cell production.

Renin-angiotensin-aldosterone System

Hormonal system regulating blood pressure influenced by kidneys.

Urinary Symptoms of Pyelonephritis

More severe symptoms including flank pain and systemic illness.

Types of Urinary Calculi

Calcium, uric acid, struvite, and cystine stones.

Symptoms of Kidney Stones

Nausea, vomiting, hematuria, and severe flank pain.

Importance of Straining Urine

To collect stones for analysis.

Impact of Aging on Medication Use

As renal clearance decreases, drugs may accumulate leading to toxicity.

Detrusor Muscle Function

Enables bladder to store and expel urine.

Normal Urine Characteristics

Should be pale yellow and clear with a mild odor.