1. CHAPTER 15
Urinary System

2. Urinary System Overview
Functions of urinary system
Removes waste products from blood
Produces and eliminates urine
Kidneys produce hormone Erythropoietin (EPO)
Stimulates production of red blood cells within bone marrow
Kidneys produce enzyme Renin
Aids in raising blood pressure

3. Structures of the Urinary System
Kidneys
Reddish-brown, bean-shaped organs located on either side of the vertebral column at back of upper abdominal cavity
Cortex
Outer layer of kidney
Contains millions of microscopic units called nephrons
Functional units of kidneys

4. Structures of the Urinary System
Kidneys: Components of Nephron
Glomerulus
Ball-shaped collection of very tiny, coiled, and intertwined capillaries
Bowman’s capsule (renal capsule)
Double-walled cup surrounding the glomerulus
Renal tubule
Proximal convoluted tubule
Loop of Henle
Distal convoluted tubule
Peritubular capillaries

5. Structures of the Urinary System
Kidneys
Medulla
Inner layer of kidney
Consist of triangular tissues called renal pyramids- loops and collecting tubules of nephron
Pyramids extend into a cuplike urine collection cavity called minor calyx
Minor calyces merge to form major calyx
Major calyces merge to form renal pelvis

6. Structures of the Urinary System
Ureters
Muscular tubes lined with mucous membrane
One leads from each kidney down to urinary bladder
Urine is propelled from renal pelvis through ureters by wavelike contractions known as peristalsis

7. Structures of the Urinary System
Bladder
Hollow, muscular sac in pelvic cavity
Between pubic symphysis and rectum in men
Between pubic symphysis and uterus and vagina in women
Serves as a temporary reservoir for urine
Spherical shaped when full
Resembles inverted pyramid when empty

8. Structures of the Urinary System
Urethra
Mucous membrane-lined tube that leads from bladder to exterior of body
Urine exits bladder through urethra
External opening of urethra is the urinary meatus
Female urethra carries only urine
Male urethra carries both urine and semen during ejaculation

9. Formation of Urine
Formation of urine consists of three distinct processes: glomerular filtration, tubular reabsorption, and tubular secretion
Process begins as blood enters kidneys via left and right renal arteries
Renal arteries branch out into smaller vessels throughout kidney tissue, until these arterioles reach cortex of kidney
Each arteriole leads to a glomerulus

10. Formation of Urine Glomerular filtration
As blood passes through the glomeruli, blood pressure forces materials through glomerular walls into Bowman’s capsule
Glomerular Filtrate = water, sugar, salts, and nitrogenous waste products such as urea, creatinine, and uric acid that filter out of blood through thin walls of glomeruli

11. Formation of Urine Tubular reabsorption Tubular secretion
As glomerular filtrate passes through renal tubules, water, sugar, and salts are returned to bloodstream through network of capillaries that surround them
Tubular secretion
Materials are selectively transferred from blood into the filtrate to be excreted in the urine

12. Formation of Urine Urine
Urine consists of water and other materials that were filtered or secreted into the tubules but not reabsorbed
Normally one percent of glomerular filtrate is excreted as urine

13. Characteristics of Normal Urine
Color
From pale yellow to a deep golden color
Darker the urine, greater the concentration
Clarity
Normal urine is clear
Cloudy, turbid appearance to the urine may be due to presence of pus, bacteria, presence of bladder or kidney infection, or a specimen that has been standing for more than an hour

14. Characteristics of Normal Urine
Odor
Normal urine is aromatic
Has a strong but agreeable odor
Specific gravity
Normal urine has specific gravity of – 1.030
Specific gravity = measurement of the amount of solids in the urine

15. Characteristics of Normal UrinepH
Normal urine is slightly acid, pH of 6.0
pH range is 4.5 – 8.0
pH represents relative acidity or alkalinity of a solution
pH of 7.0 is neutral
pH below 7.0 is acid
pH above 7.0 is alkaline (base)

16. Characteristics of Normal Urine
Protein
Normal urine may have small amounts of protein present
Only in insignificant amounts, too small to be detected by reagent strip
Glucose
Normal urine does not contain glucose

17. Characteristics of Normal Urine
Ketones
Normal urine does not contain ketone bodies
Ketones result from the breakdown of fats

18. Common Signs and Symptoms
Albuminuria
Presence in urine of abnormally large quantities of protein, usually albumin
Also known as proteinuria
Anuria
Cessation (stopping) of urine production, or a urinary output of less than 100 ml per day

19. Common Signs and Symptoms
Bacteriuria
Presence of bacteria in urine
Dysuria
Painful urination
Enuresis
Condition of urinary incontinence, especially at night in bed
Bedwetting

20. Common Signs and Symptoms
Fatigue
State of exhaustion or loss of strength or endurance
May follow strenuous physical activity
Frequency
In case of urinary frequency = urination at short intervals (frequently) without increase in the daily volume of urinary output due to reduced bladder capacity

21. Common Signs and Symptoms
Glycosuria
Abnormal presence of sugar, especially glucose, in urine
Hematuria
Abnormal presence of blood in urine

22. Common Signs and Symptoms
Ketonuria
Presence of excessive amounts of ketone bodies in urine
Lethargy
State or quality of being indifferent, apathetic (without emotion), or sluggish

23. Common Signs and Symptoms
Malaise
Vague feeling of bodily weakness or discomfort, often marking the onset of disease of infection
Nocturia
Urination, especially excessive, at night
Also called nycturia

24. Common Signs and Symptoms
Oliguria
Secretion of a diminished amount of urine in relation to fluid intake
Scanty urine output
Polydipsia
Excessive thirst

25. Common Signs and Symptoms
Polyuria
Excretion of abnormally large amounts of urine
Pyuria
Pus in urine, usually a sign of an infection of urinary tract
Urgency
Feeling to void urine immediately

26. PATHOLOGICAL CONDITIONS
Urinary System

27. Cystitis Pronounced Defined (siss-TYE-tis)
Inflammation of urinary bladder
Characterized by urgency and frequency of urination, and by hematuria

28. Glomerulonephritis (Acute)
Pronounced
(gloh-mair-yoo-loh-neh-FRYE-tis)
Defined
Inflammation of glomerulus of kidneys
Condition characterized by proteinuria, hematuria, and decreased urine production

29. Hydronephrosis Pronounced Defined (high-droh-neh-FROH-sis)
Distension of pelvis and calyces of the kidney caused by urine that cannot flow past an obstruction in a ureter

30. Hydronephrosis

31. Nephrotic Syndrome Pronounced Defined (neh-FROT-ic SIN-drohm)
Clinical symptoms occurring when damage to glomerulus of the kidney is present and large quantities of protein are lost through the glomerular membrane into urine
Results in severe proteinuria
Also called nephrosis

32. Polycystic Kidney Disease
Pronounced
(pol-ee-SISS-tic kidney dih-ZEEZ)
Defined
Hereditary disorder of kidneys in which grapelike, fluid-filled sacs or cysts, replace normal kidney tissue

33. Pyelonephritis (Acute)
Pronounced
(pye-eh-loh-neh-FRY-tis)
Defined
Bacterial infection of the renal pelvis of the kidney
Infection begins in the bladder and travels up the ureters to the renal pelvis

34. Renal Calculi Pronounced Defined (REE-nal KAL-kew-lye)
Stone formations in kidney

35. Renal Cell Carcinoma Pronounced Defined (REE-nal SELL car-sin-OH-mah)
Malignant tumor of kidney occurring in adulthood
Patient is asymptomatic (symptom free) until latter stages of disease

36. Renal Failure, Chronic Pronounced Defined (REE-nal FAIL-yoor, KRON-ik)
Progressively slow development of kidney failure occurring over a period of years
Late stages of chronic renal failure known as end-stage renal disease (ESRD)

37. Vesicoureteral Reflux
Pronounced
(vess-ih-koh-yoo-REE-ter-al REE-fluks)
Defined
Abnormal backflow (reflux) of urine from the bladder to the ureter

38. Wilm’s Tumor Pronounced Defined (VILMZ TOO-mor)
Malignant tumor of the kidney occurring predominately in childhood
Most frequent finding is palpable mass in the abdomen

39. Treatment of Renal Failure
Peritoneal Dialysis
Mechanical filtering process
Used to cleanse blood of waste products, draw off excess fluids, and regulate body chemistry when kidneys fail to function properly
Peritoneal membrane is used as filter

40. Treatment of Renal Failure
Continuous Ambulatory Peritoneal Dialysis (CAPD)
Requires transfer set, connected to bag of dialysate solution
Dialysate solution remains in abdomen for approximately four hours after exchange
Process is repeated 3 to 5 times daily
Advantage: No machine, convenient for travel

41. Treatment of Renal Failure
Continuous Ambulatory Peritoneal Dialysis

42. Treatment of Renal Failure
Continuous Cycling Peritoneal Dialysis (CCPD)
Uses a machine that warms the solution and cycles it in and out of the peritoneal cavity at evenly spaced intervals at night while the patient sleeps
Process takes 8 to10 hours
Last exchange remains in abdomen during the day for approximately 12 to15 hours

43. Treatment of Renal Failure
Continuous Cycling
Peritoneal
Dialysis

44. Treatment of Renal Failure
Hemodialysis
Process of removing excess fluids and toxins from blood by continually shunting patient’s blood from body into a dialysis machine for filtering, and returning clean blood to patient’s bloodstream
Usually three treatments a week, 3 – 4 hours at a time
May be performed at dialysis center or at home

45. Treatment of Renal Failure
Hemodialysis

46. Treatment of Renal Failure
Arteriovenous fistula
Access vessel created for use with hemodialysis
Opening or fistula is created between an artery and a vein in the forearm
Flow of arterial blood into venous system at point of fistula causes vein to become distended
Provides a large enough vessel with a strong blood flow for the hemodialysis connection

47. Treatment of Renal Failure
Arteriovenous fistula for hemodialysis

48. Treatment of Renal Failure
Kidney transplantation
Surgical implantation of a healthy, human donor kidney into the body of a patient with irreversible renal failure
Kidney function is restored with a successful transplant and the patient is no longer dependent on dialysis
Donor kidney may come from living donor (usually blood relatives) or cadaver donors (nonliving matches)

49. Treatment of Renal Failure
Kidney transplantation
Donor kidney surgically placed in iliac fossa
Donor renal artery connected to recipient’s iliac artery
Donor renal vein connected to recipient’s iliac vein
Donor ureter connected to recipient’s bladder
Donor kidney usually functions once it is in place

50. DIAGNOSTIC TECHNIQUES, TREATMENTS AND PROCEDURES
Urinary System

51. Diagnostic Techniques, Treatments, and Procedures
Blood Urea Nitrogen (BUN)
Blood test performed to determine amount of urea and nitrogen (waste products normally excreted by the kidney) present in blood
Catheterization
Introduction of a catheter into a body cavity or organ to instill a substance or remove a fluid

52. Diagnostic Techniques, Treatments, and Procedures
Creatinine clearance test
Diagnostic test for kidney function that measures filtration rate of creatinine, a waste product (of muscle metabolism), which is normally removed by kidney
Cystometrography
Examination performed to evaluate bladder tone; measuring bladder pressure during filling and voiding

53. Diagnostic Techniques, Treatments, and Procedures
Cystoscopy
Process of viewing interior of bladder using a cystoscope
Extracorporeal lithotripsy
Non-invasive mechanical procedure for breaking up renal calculi so they can pass through ureters
Also known as extracorporeal shock-wave lithotripsy

54. Diagnostic Techniques, Treatments, and Procedures
Intravenous pyelogram
Radiographic procedure that provides visualization of the entire urinary tract: kidneys, ureters, bladder, and urethra
Contrast dye is injected intravenously
Multiple x-ray films are taken as medium is cleared from blood

55. Diagnostic Techniques, Treatments, and Procedures
KUB (Kidneys, Ureters, Bladder)
X-ray of lower abdomen that defines size, shape, and location of the kidneys, ureters, and bladder
Contrast medium is not used with this x-ray
Renal angiography
X-ray visualization of internal anatomy of renal blood vessels after injection of a contrast medium

56. Diagnostic Techniques, Treatments, and Procedures
Renal scan
Radioactive isotope (tracer) is injected intravenously
Radioactivity over each kidney is measured as tracer passes through kidney

57. Diagnostic Techniques, Treatments, and Procedures
Retrograde Pyelogram (RP)
Radiographic procedure in which small-caliber catheters are passed through a cystoscope into ureters to visualize ureters and renal pelvis

58. Diagnostic Techniques, Treatments and Procedures
Ultrasonography
Procedure in which sound waves are transmitted into body structures as a small transducer is passed over patient’s skin
Also called ultrasound
Urinalysis
Physical, chemical, or microscopic examination of urine

59. Diagnostic Techniques, Treatments, and Procedures
Urine culture
Procedure used to cultivate the growth of bacteria present in a urine specimen, for proper microscopic identification of the specific pathogen
Sample of urine specimen swabbed onto a culture medium plate and placed into an incubator for 24 to 72 hours
Plate is then examined for growth on culture medium

60. Diagnostic Techniques, Treatments, and Procedures
24-Hour urine specimen
Collection of urine excreted by the individual over a 24-hour period
Urine collected in one large container
Also called a composite urine specimen
Voiding cystourethrography
X-ray visualization of bladder and urethra during voiding process after bladder has been filled with a contrast material

61. Urine Specimen Collections
Catheterized specimen
Also known as a sterile specimen
Using aseptic techniques, a very small, straight catheter is inserted into the bladder via the urethra to withdraw a urine specimen
Urine flows through catheter into a sterile specimen container

62. Urine Specimen Collections
Clean-catch specimen
Also known as midstream specimen
Collection method used to avoid contamination of the urine specimen from the microorganisms normally present on the external genitalia
Patient cleanses external genitalia with antiseptic wipe
Expels small amount of urine into toilet, then collects specimen in sterile container

63. Urine Specimen Collections
First-voided specimen
Also known as an early-morning specimen
Patient instructed to collect first voided specimen of the morning
Specimen should be refrigerated until it can be taken to the medical office or laboratory

64. Urine Specimen Collections
Random specimen
Urine specimen that is collected at any time
Residual urine specimen
Specimen obtained by catheterization after the patient empties the bladder by voiding
Amount of urine remaining in the bladder after voiding is noted as the residual amount