Lesson 2 Urinary Elimination

Micturition

The act of voiding

Micturition trigger volume

Person feels desire to void at about 150-250 mL (adult)

Micturition mechanism

When urination initiated, detrusor muscle contracts, internal sphincter muscle relaxes, and urine enters urethra (result of parasympathetic reflex); perineal and external sphincter muscles relax and urination occurs

Micturition center location

Pons

Internal urethral sphincter muscle type

Smooth muscle innervated by autonomic nervous system (involuntary control)

Parasympathetic innervation effect on urination

From sacrum; promotes urination by contracting detrusor muscle and relaxing internal urethral sphincter

Sympathetic innervation effect on urination

From thoracic spine; inhibits urination by relaxing detrusor and contracting internal urethral sphincter

External urethral sphincter control

Controlled by somatic motor nerves (not autonomic) from sacrum; made of skeletal muscle under voluntary control; when contracts, urine flow is prevented

Urinary assessment - inspection

Urethral meatus if needed, observe lower abdominal wall for swelling, skin integrity, hydration status, examination of urine

Empty bladder location

Below pubic symphysis and cannot be seen nor palpated

Bedside bladder scan

Can be used to assess fullness

Urinary assessment - palpation

Bladder location and size; palpate gently and lightly; non-distended bladder is not palpable

Urinary assessment - percussion

Can indicate if bladder is distended

Minimum urine output per hour

30 mL/hr minimum

Urine output

Diminished blood flow to kidneys/kidney damage

Normal volume per void

150-250 mL per void

Post-void residual (PVR) normal

When voiding,

Abnormal post-void residual (PVR)

>100 mL is abnormal

Urine output calculation

0.5 to 1.5 mL/kg/hour

Normal urination frequency

Every 3-4 hours

Habitual infrequent urination risk

Increased risk for UTIs (stagnation of urine in bladder leads to bacterial growth)

Dehydration effect on urine

Kidneys reabsorb more fluid; urine is concentrated and decreased in volume

Fluid overload effect on urine

Kidneys excrete large amount of dilute urine

Alcohol (ETOH) effect on urine

Diuretic effect due to inhibition of ADH

High sodium foods effect on urine

More Na and H2O is reabsorbed and less urine is formed

Exercise effect on urination

Regular exercise promotes optimal urine production and elimination

Immobility effect on urination

Decreased bladder and sphincter tone; poor urinary control and urinary stasis

Indwelling catheter effect on bladder

Drains urine as soon as formed, so bladder tone is lost as it is not stretching with urine

Childbearing effect on bladder

Can decrease bladder muscle tone

Menopause effect on bladder

Decreased estrogen leads to muscle atrophy

Pathological conditions affecting urination

Polycystic kidney disease, UTI, urinary calculi (kidney stones), hypertension, diabetes, acute kidney injury, chronic kidney disease, renal failure/ESRD, heart failure

Diabetes effect on urination

High glucose levels increase urination due to osmotic diuretic effect

Acute kidney injury (AKI)

Acute and reversible decline in kidney function

Heart failure effect on urination

Fluid retention and decreased urine output

Promoting healthy urination - schedule

Support patient's usual urination schedule

Promoting healthy urination - urge

Assist patient when first urge to urinate appears

Promoting healthy urination - privacy

Provide privacy unless patient requires assistance

Promoting healthy urination - position

Difficult to urinate lying down (bedpan or urinal); offer bedside commode (female) or standing urinal (male)

Promoting healthy urination - hygiene

Careful cleaning of perineal and genital areas

Toileting requirements

Patient needs dexterity and mobility; ensure privacy; maintain professional demeanor

Regular bedpan use

Roll or lift patients onto bedpan when needed but always maintain maximum level of independence

Obstruction of urine flow causes

Renal calculi, benign prostatic hyperplasia, blocked indwelling catheter

Decreased muscle tone causes

Obesity, pregnancy, chronic constipation (straining), long-term catheter use, advancing age

Long-term catheter use effects

Decreased muscle tone and atrophy; upon removal: poor sphincter muscle control and risk for dribbling (can improve with time)

Advancing age effect on urination

Decreased estrogen leads to decreased muscle tone

Incontinence and aging

INCONTINENCE IS NOT A NORMAL OCCURRENCE OF AGING

Stress incontinence definition

Involuntary loss of urine caused by increase in intraabdominal pressure (laugh, cough, sneeze, exercise, heavy lifting) and weak perineal and abdominal muscle tone

Stress incontinence causes

Urethral external sphincter dysfunction

Stress incontinence risk factors

Poor muscle tone

Stress incontinence treatment

Pelvic Floor Muscle Training (PFMT) by Pelvic PT; Kegel exercises

Kegel exercises technique

Tighten pelvic floor muscles and hold for count of 10; relax muscles completely for count of 10

Kegel exercises caution

OVER-EXERCISING CAN INCREASE LEAKAGE

Urge incontinence definition

Loss of urine from the time patient feels urge to urinate to the time it takes to get to bathroom

Urge incontinence causes

Involuntary bladder contractions (BLADDER SPASMS - IRRITATED!), decreased capacity

Urge incontinence risk factors

UTI (frequency and urgency), medications (diuretics), bladder irritants (alcohol, caffeine, spicy foods, increased fluid intake), over-distended bladder, ignoring the urge to void

Urge incontinence treatment

Prevention! Prompted voiding; toilet every 2 hours

Managing incontinence - pads/briefs

Can increase risk of UTI/skin breakdown; always assess

Managing incontinence - skin care

Perineal care multiple times a day; skin barriers; skin prep

Indwelling catheter care - prevent pulling

Anchor tubing but allow room for leg movement; tape and/or leg band

Indwelling catheter care - ensure drainage

Dependent loops increase risk for hydronephrosis (fluid back up)

Urine assessment location

Look at urine in TUBING not the BAG

Alternative urinary catheter (female)

Connected to low continuous wall suction

External condom catheter (male)

Used when voluntary control of urine is not possible for patients with penis; diverts urine away from body into collection bag

Condom catheter care

Connect to leg bag; remove every day to wash penis with soap and water; allow 1-2 inches of space at tip

Collection bag types

Hanging bag, belly bag, bag with urimeter, leg bag (can increase independence)

Urinary output documentation - voiding

Use hats in toilet; measure mL per void; if incontinent, document number of times voided; can measure by weighing absorbent pads

Urinary output documentation - catheter

Measure per shift; hourly with urimeter bag

UTI upper tract

Kidneys/ureters - pyelonephritis

UTI lower tract

Bladder/urethra - cystitis

UTI causes

Catheter associated urinary tract infection (CAUTI), length of urethra (female), cleanliness issues (not voiding after sex, bubble baths, infrequent voiding)

Most common UTI bacteria

E. coli

UTI classic symptoms

Pain or burning while urinating (dysuria), frequent urination (frequency and urgency), hematuria, pressure or cramping

UTI treatment

Short course of antibiotics 3-7 days for lower urinary tract infections; longer course for more severe infections

UTI patient education - fluids

Drink 6-8 ounces of liquid daily

UTI patient education - voiding

Urinate when you feel urge; take time to empty full bladder when urinating

UTI patient education - hygiene (female)

Dry perineal area after urination and/or defecation from front to back

UTI patient education - sexual activity

Void before and after sex (intercourse)

UTI patient education - contraception

Frequent UTI and using contraception? Talk to provider about switching methods if using unlubricated condoms, diaphragm, or spermicide

UTI patient education - clothing

Wear underwear with cotton crotch; avoid tight/restrictive underwear

Urine specimen collection precautions

Avoid contamination with feces or tissue; store in refrigerator; if patient has menses, note on requisition form

Urinalysis collection amount

Minimum 10 mL

Urine culture collection amount

Minimum 3 mL

Routine urinalysis timing

First morning void preferred (most concentrated)

Routine urinalysis collection method

Collect from urinal, bedpan, hat, or condom catheter bag; make sure not contaminated with feces or toilet paper; refrigerate if unable to take to lab immediately

Routine urinalysis testing

Usually tested with reagent sticks

Urinalysis (UA) components

Color, turbidity, pH, specific gravity, protein, glucose, ketones (from fat breakdown), RBC, WBC, bacteria, casts

Casts in urine

Can be made up of WBC, RBC, or other substances

Clean catch urine uses

Culture and Sensitivity (C&S); can be used for UA also

Clean catch urine for microbial testing

Send directly to lab warm!

Clean catch urine technique

After hand hygiene, cleanse area, void small amount in toilet (about 30 mL), then collect some in cup; initial voiding flushes away organisms near meatus; don't touch inside of cap or cup

24 hour urine collection procedure

Collect urine for 24 hours; initiate at specified time; discard first void; include last void; if you discard any other urine, you have to restart (invalidating); post door or bed sign as reminder

24 hour urine collection patient teaching

Usually void into hat and then pour into container - difficult to 'aim' correctly and preservative can splash causing skin burn

24 hour urine collection preservation

May or may not contain preservative; if not, refrigerate or place container on ice

24 hour urine collection purpose

To measure kidney excretion of specific substances like protein, creatinine, uric acid

Anuria

24-hour urine output is less than 50 mL

Dysuria

Painful or difficult urination

Frequency

Increased incidence of voiding

Glycosuria

Presence of glucose in urine

Nocturia

Awakening at night to urinate

Oliguria

24-hour urine output is less than 400 mL