MMSC402 - Exam 1

proficiency testing

surveys or programs in which many labs use same lot of QC materials

- reports are useful for detecting quantitative small changes in systematic errors in quantitative methods

- accredited labs must participate in them

documented

an action has not been performed if it has not been _________

OSHA (Occupational Safety and Health Act of 1970)

- established formal regulation of health and safety for all employees

- administered by _________

Standard precautions and transmission based precautions

These precautions state that all body fluids except sweat are considered potentially infectious

Transmission- based precautions

these precautions apply to specific patients with known or suspected infections

Contact, droplet, and airborne

3 types of transmission based precautions

Airborne precautions

Methods of infection control that must be used for patients known or suspected to be infected with pathogens transmitted by airborne droplet nuclei.

Droplet precautions

Must be followed for a patient known or suspected to be infected with pathogens transmitted by large-particle droplets expelled during coughing, sneezing, talking, or laughing.

contact precautions

Methods of infection control that must be used for patients known or suspected to be infected with epidemiological microorganisms that can be transmitted by either direct or indirect contact.

inhalation, ingestion, and direct inoculation or skin contact

Three routes of infection or disease transmission:

- proper labeling of chemicals

- lab safety manual

- Use of PPE

- safety equipment such as an eyewash and shower

4 components of OSHA rules

biopsy

urinalysis is a fluid _______ of the kidney

ultrafiltrate

urine is _________ of plasma and can be used to evaluate and monitor body homeostasis and many metabolic diseases

excess fluid intake or exercise

random urine screenings can be affected by what two things?

first morning void

Urine that is produced during the night and collected in the morning at the first void

- this is the most preferred specimen

timed specimen

urine specimen...

- collected for predetermined length of time

- collected at a specified time of day

mid stream or "clean catch"

a urinalysis where you begin urination into the toilet, collect the midstream portion in the container, and finishing voiding into the toilet

bacterial cultures, and to prevent vaginal contamination

- sterile container

- glans penis and urethral meatus

med stream urinalysis is used for...

need a ______ container

- requires thorough cleaning and rinsing of the _______ _____ or _________ _____ before collection

catheterized specimen

a urine specimen collected by a sterile catheter inserted through the urethra and into the bladder, specimen flows directly into the collection bag and can be obtained anytime

suprapubic aspiration

urinalysis that involved puncturing of abdominal wall and distended bladder by using needle and syringe

- sample is aspirated directly from the bladder

- bladder urine is sterile

- used for cultures or in infants

pediatric urine collections

- usually urine is collected commercially with plastic urine collection bags that attach with a hypoallergenic skin adhesive

- perineal area is cleaned prior to the bag attachment

- specimen is removed ASAP after collection

- for routine testing

1. unlabeled or mislabeled - label on container not lid

2. mismatch of specimen name or identification (ID) number with order slip

3. inappropriate collection technique for test that was ordered

4. not properly preserved or there is a time delay in the receipt of the specimen

5. visibly contaminated specimen

6. insufficient volume for tests ordered

6 reasons for rejection of a urine specimen

- alteration of urine solutes to a different form

- bacterial growth

- solute precipitation

changes in unpreserved urine result from what 3 things;

- decreased urine clarity

- increased urine odor

- color changes possible from solute changes

- false-negative glucose

- false negative ketones

- increased nitrite and pH

- disintegration of formed elements

7 changes that result from an unpreserved urine specimen

- type of collection

- tests to be performed

- time delay before testing

What are three preservative considerations

refrigeration; 2

_________ is the most common preservation technique, but should not be used for routine testing if urine will be analyzed within ___ hours

chemical preservative

12 and 24 hour timed collections require addition of a _________ ________ to maintain integrity of the analyte to be tested

ice or refrigerate

keep on _____ or _____________ during the collection period of long time urine collections

...and deliver specimen to lab immediately after completion of collection period

urea, sodium, and chloride

What solutes establish and maintain the osmotic gradient set up by the loop of Henle?

they are also higher in urine than in other body fluids

1.002 to 1.0035

Normal random specific gravity of urine

4 to 8

pH normal ranges of urine

creatine

urine ________ is 50 times higher than in plasma

glomeruli

located in the outer cortex of the kidney; the exclusive site of plasma filtration

medulla

kidney part that consists of pyramid-shaped tissue;

each pyramid has a duct that enters a calyx

calyces

________ funnel urine from collecting tubules to the renal pelvis

ureter

bladder

150

bladder

sphincter

Flow of urine:

- urine from each renal pelvis enters a _________, which is about 25 cm long

- it then passes into the ___, which serves as a holding area

- when about ___ mL of urine accumulates, a nerve reflex signals an urge to urinate

- contraction of the _______ and relaxation of urinary ______ push urine into the urethra leading to the outside of the body

4 cm in women

24 cm in men

how long is the urethra in women and in men

1. glomerulus

2. proximal convoluted tubule

3. loop of Henle

4. distal convoluted tubule

5. collecting tubule

What are the 5 distinct areas of the nephron of the kidney?

glomerulus

capillary tuft surrounded by Bowman's capsule, where filtration occurs

tubules

reabsoprtion and secretion of small molecules take place in the _________, also reabsorption of water to concentrate the urine

afferent arteriole

branches

efferent arteriole

plexus

the glomerulus:

- an ___________ ________ supplies blood individually to the glomerulus of each nephron

- _________ into a capillary tuft on entering

- capillaries come back together to form ________ ______ on exiting

- efferent arteriole branches a second time into a capillary ______

high hydrostatic pressure

__________ ______ _____ of the afferent arteriole is driving force behind glomerular filtration

renin

large amounts of secretory granules containing enzyme _____ are present in afferent arteriole of juxtaglomerular apparatus

1. decreased arteriole blood pressure or volume

2. decreased sodium (Na) or increased potassium

3. vascular hemorrhage

renin is released in response to what three things?

angiotensin; aldosterone

renin causes ________ formation and _________ secretion

sodium and water

BP

aldosterone causes the kidneys to retain ___ and ___

- this will rise as a reuslt?

180,000 mL

How much filtered plasma does the kidneys convert per day into urine

- plasma

- renal tubules

urine formation consists of:

- _______ filtration of glomeruli

- reabsorption and selective secretion by _____ ____

- removal of metabolic wastes

- water and electrolytes

- acid-base equilibrium

Kidneys play important roles in:

- removal of _________ _______

- regulation of _______ and _______

- maintenance of body's ___________ ________ _________--

capillary endothelium

basement

diaphragms

three structures of glomerulus filtration barrier:

- ______ _______ with its large open pores

- trilayer _________ membrane

- filtration _______ located between podocytes of Bowman's space

negative charge

glomerulus endothelium has a _______ _____ that large molecules have to overcome to pass

reabsorption

back to the blood

secretion

to the urine

active

passive

tubular transport mechanisms are either ____ or ______

tubule

each solute has a specific transport system that may differ by area of the ____ that is occurs

creatinine

tubules selectively reabsorb substances and they do not reabsorb waste products such as _______

- eliminate wastes and substances not normally present in plasma

- adjust acid-base status of the body

secretion occurs to do what two things?

metabolic or exogenous sources

most substances secreted are weak acids or bases from ___________ or _____ sources

H+,, NH3, weak acids and bases

What three things do the proximal tubule ultrafiltrate for tubular secretion?

urea

What does the loop of Henle ultrafiltrate for tubular secretion?

H+, NH3, K+, uric acid, and some drugs

What five things do the distal tubule ultrafiltrate for tubular secretion?

H+, NH3, K+, some drugs

What four things do the collecting tubule ultrafiltrate for tubular secretion?

7.35 to 7.45

What is the normal range pH of blood?

1. blood bicarbonate buffer system

2. pulmonary system

3. renal system

What are the three systems involved in the maintenance of pH?

buffers

______ prevent pH from changing

carbon dioxide

lungs can exhale or retain ______ _____ (an acid)

hydrogen ions, ammonia, bicarbonate

renal system increases or decreases excretion of ________ _______, formation of ________, and reabsorption of ____________

tubule epithelium

negative

positive

ADH causes a change in _________ _______, and increased water reabsorption occurs; this release of ADH is controlled by __________ feedback with arterial blood pressure, and _______ feedback with plasma osmolality

soluble

renal excretion is primary elimination route of _______ metabolic wastes

osmolality

the concentration of a solution expressed as the total number of solute particles per kilogram.

- affected by solute number, NOT SIZE OR WEIGHT

distal and collecting tubules

- final osmolality is determined in ____________ and __________ ________ when ADH is present

1 to 3 times

normally urine osmolality is ____ to ____ ______ that of plasma

specific gravity

the comparison of density of urine to that of water

- depends on number of particles and mass

1.002 to 1.035

What is the normal range for specific gravity?

polyuria

urine amount greater than 3L/day

water and solute

polyuria is caused by condition with ________ and ______ diuresis

- 1. ADH secretion inadequate or receptors ineffective

-2. no common feature, but involve glucose, urea, or sodium

oliguria

urine output less than 400 mL/day

- urinary obstruction

- tubular dysfunction

- fluid loss

oliguria is caused by what three things?

anuria

absence of urine, caused by progressive renal disease or renal failure

osmolality

_______ is preferred because it is a more accurate reflection of the kidney's concentrating ability, since only solute number affects it

urea

sodium

chloride

three most prevalent solutes in urine

unchanging

polyuria and nocturia

in some chronic renal diseases, concentrating ability slowly diminishes until specific gravity or osmolality are __________

- urine concentration becomes the same as the ultrafiltrate

- specific gravity of 1.010 or approx. 300 mOsm/kg

- causes _______ and _______

fluid deprivation tests

Used to differentiate causes of polyuria due to water diuresis

- water consumption is restricted and urine specimen is checked about every 12 hours later

- if the urine is concentrated, test is ended, if not it continues

ADH decreased

"Neurogenic" diabetes insipidus is due to what?

lack of renal response to ADH

nephrogenic diabetes insipidus is caused by?

Glomerular filtration rate

amount of filtrate formed in all the renal corpuscles of both kidneys each minute

directly

volume of plasma filtered ________ affects volume and composition of urine excreted

renal clearance tests

determine the efficiency with which the kidneys excrete particular substances

- volume of plasma in mL that is completely cleared of a substance per unit of time

C = U(mg/dL) x V(mL/min) / P(mg/dL)

you calculate renal clearance (C) using plasma concentration of substance (P), urine concentration (U), and volume of urine (V), what's the equation?

GFR

tests for _______ use substances solely by glomerular filtration (inulin)

tubular secretion

tests for _______ _____ use substances removed solely by tubular secretion (PSP)

clearance

endogenous or exogenous substances can be used in ___________ tests

creatinine

__________ clearance is the most common test used

creatinine

waste product of creatine in muscles, produced at a relatively constant rate and excreted by kidneys

24

plasma

volume

surface area

C (mL/min)= (UxV)/P x 1.73m^2/SA

creatinine clearance tests:

- requires a _ hour urine creatinine (U) and serum/_____ creatinine (P) drawn sometime during urine collection time, urine ____ (V), and an estimate of body ______ ______ ( from height and weight using a nomogram)

- what is the equation?

easy

precision

tubules

- plasma and urine creatinine tests are ______ to perform

- accuracy and ______ of the methods are well studied

- small amount of creatinine secreted by the ______, resulting in an increased urine concentration of creatinine

Jaffe

V

- if nonspecific _______ method is used to measure this, P creatinine will be overestimated, offsetting increased __ value, giving values close to inulin clearance results

Estimated Glomerular Filtration Rate (eGFR)

simple effective tool that helps to detect chronic kidney disease

- used for high risk individuals with diabetes, HTN, heart disease, or family Hx of kidney disease

- calculation based on serum creatinine level and patient's age, gender, and ethnicity

60

most accurate values of eGFR are less than or equal to _____ mL/min, therefore values greater than that are reported as >60mL/min and less than is reported AS

Beta 2 - microglobulin

a low molecular weight protein found on the surface of nucleated cells and shed into the plasma

- readily passes through the glomeruli and is 99.9% reabsorbed by proximal tubules