BF - Unit 1 Study Guide PDF

Chapter 1: Safety and QA ​ List six major hazards possible found in a clinical laboratory. ○​ biohazard, sharps, chemical, radiological, physical, electrical ​ Identify three (3) common blood-borne pathogens that have laboratory safety implications. ○​ Hep B, Hep C,...

Chapter 1: Safety and QA ​ List six major hazards possible found in a clinical laboratory. ○​ biohazard, sharps, chemical, radiological, physical, electrical ​ Identify three (3) common blood-borne pathogens that have laboratory safety implications. ○​ Hep B, Hep C, HIV, TB ​ Define: ○​ Host ○​ Reservoir ○​ Aerosol ○​ Standard Precautions: minimum infection control practices that apply to all patient care ​ Identify the personal protective equipment (PPE) used by laboratory personnel. ○​ gloves, lab coat, mask (N95), goggles or face shield ​ List the components of the chain of infection. ○​ germs, where germs live (reservoir), how germs get out, how germs get around, how germs get in, next sick person ​ Describe the different modes of transmission. ○​ direct contact: unprotected host touches patient, specimen, or contaminated object ○​ airborne: inhalation of dried aerosol particles circulating on air currents or attached to dust particles ○​ droplet: host inhales material from reservoir ○​ vehicle: ingestion of contaminated substance ○​ vector: from an animal or insect bite ​ Describe the NFPA symbol. ○​ red = flammability ○​ yellow = instability ○​ blue = health hazard ○​ white = specific hazard (ex. oxidizer, acid, alkali, corrosive, use NO water, radiation) ​ Describe the two acronyms used in the event of a fire. ○​ RACE (rescue, alarm, contain, extinguish/evacuate) ○​ PASS (pull pin, aim at base of fire, squeeze handles, sweep nozzle) ​ Explain the method for disposing of urine specimen. ○​ pour down the toilet or sink (if there isn’t blood, infection, etc.) ○​ dispose of container in biohazard QC in Urinalysis ​ Define the following: ○​ Quality Control: set of procedures and measures used to ensure that lab produces accurate, reliable, and reproducible results ○​ Delta Checks: compares patient’s current lab results with previous results to detect significant changes; large changes may indicate errors or significant clinical changes ○​ Critical values: test results that fall outside normal ranges that may indicate  life-threatening situations ○​ Error Variables ​pre-analytical: occur before testing ​analytical: occur during testing process ​post-analytical: occur after testing ○​ Reliability: consistency and dependability of test results over time ○​ Standards: substances or materials with known properties or concentrations used to calibrate instruments and validate lab methods ○​ Controls: samples with known values run alongside patient specimens to monitor performance of lab assays ○​ Proficiency testing: method of external QA where labs analyze unknown samples provided by an external agency; results are compared to those of other labs to evaluate performance and accuracy ○​ Accuracy: degree where a test result matches the true value or standard; high accuracy = result is close to actual value ○​ Precision: consistency of test results; high precision = low variability ​ State the corrective action for quality controls results that are out of range. ○​ stop patient testing, search for cause, retest after it has been fixed; if issue has been solved, patient testing can be resumed Chapter 3: Intro to Urinalysis ​ Describe the collection processes for all types of body fluids including spinal fluid and urines. ○​ lumbar puncture → CSF ○​ thoracentesis → pleural fluid ○​ pericardiocentesis → pericardial fluid ○​ paracentesis → peritoneal fluid (ascites) ​ Name the individual laboratory departments involved in testing body fluids and what they do to analyze the fluids. ○​ hematology ○​ clinical chemistry → glucose, protein ○​ microbiology → gram stain, cultures ○​ cytology/pathology ​ State the primary solutes in normal urine ○​ urea, creatinine, uric acid, chloride, sodium, potassium, phosphate, ammonium, calcium ​ State the basic composition of urine ○​ urine = urea + organic chemicals + inorganic chemicals + water ​ State the average daily urine volume from a normal adult. ○​ 1200-1500 mL/day ​ What happens to urine after sitting at room temperature for greater than 2 hours? ○​ change in color ○​ decrease in clarity, glucose, ketones, bilirubin, urobilinogen, trichomonas, RBCs, WBCs,  and casts ○​ increase in odor, pH, nitrite, and bacteria ​ Describe urine specimen collection techniques/procedures ○​ Midstream clean void: less contaminated ○​ Catheterization: catheter is inserted through urethra into bladder ○​ Suprapubic aspiration: needle inserted through abdomen into bladder ○​ Pediatric collection bags: clear plastic bags with skin adhesive attached to genital area ○​ Random void: common; can be done at any time; used for routine screening ○​ First morning void: ideal for screening specimen bc it’s concentrated; best for pregnancy testing and evaluating proteinuria ○​ Timed (aka 24 hour): urine is collected over 24 hours; measures exact amount of urine chemicals and volume of urine throughout the day ​ Define the different urine volume terminology: ○​ Oliguria: decrease in urine output ○​ Anuria: no urine flow ○​ Nocturia: increased nocturnal excretion of urine ○​ Polyuria: increase in urine excretion ​ State the different methods of preservation of urine. ○​ refrigeration ○​ boric acid ○​ formalin ○​ sodium fluoride ○​ commercial preservative tablets ​ Define requisition. ○​ the official order claiming the use of property or materials Chapter 4: Renal Function ​ Identify and describe the function of the structures in the urinary tract system. ○​ Ureters: transport urine from kidney to bladder ○​ Bladder: stores urine ○​ Urethra: carries urine from bladder to outside of body ​ List the different renal functions. ○​ elimination of excess water, foreign substances (drugs), and waste products (ex. urea and creatinine) ○​ retention of substances (glucose, electrolytes, minerals, amino acids) necessary for normal body function ○​ regulation of electrolyte balance and osmotic pressure of body fluids ○​ acid/base balance maintenance ○​ hormone production ​ Identify each portion of the nephron: Bowman’s capsule, PCT, Ascending and Descending limbs of the Loop of Henle, DCT, Collecting duct  ​ Label the structures that transport blood throughout the kidney. ○​ Afferent and efferent arterioles ○​ Glomerulus ○​ Peritubular capillaries ○​ Vasa recta ​ State the function of each component of the glomerulus ○​ Capillary endothelium: has pores; blocks large molecules and cells ○​ Basement Membrane: further restricts large molecules ○​ Podocytes: membrane covered filtration slits Kidney Physiology ​ Describe the processes involved in glomerular filtration ○​ Hydrostatic and oncotic forces ​hydrostatic pressure: blood pressure in glomerulus pushes fluid into kidney tubule ​oncotic pressure: proteins in blood pull water back into capillaries ​these forces determine how much fluid is filtered ○​ Glomerular filtration barrier → 3 layers that prevent large particles from passing through ○​ Glomerular filtration rate → amount of fluid filtered per minute ​ Describe the process of urine formation: ○​ Tubular reabsorption and secretion ○​ active transport: must be attached to carrier proteins and cellular energy is needed for transport back to blood ​proximal convoluted tubule: glucose, salts, amino acids ​ascending loop of Henle: chloride ​distal convoluted tubule: sodium ○​ passive transport: controlled by differences in substance concentration gradients on sides of membrane ​ List the solutes that are actively reabsorbed by the nephron ○​ glucose, salts, amino acids, chloride, sodium ​ List the solutes that are passively reabsorbed by the nephron ○​ urea, sodium ​ List the solutes that are secreted by the nephron ○​ hydrogen ions, urea, ammonia, potassium ions ​ Summarize secretory mechanisms that regulate acid-base balance ○​ Hydrogen ion secretion to recover bicarbonate ○​ Hydrogen ion secretion to form acids ○​ Hydrogen ion secretion to form ammonium ions ​ Describe the influence of the following hormones on the urine production and elimination. ○​ antidiuretic hormone (ADH): increases water retention and reduces urine output ○​ renin: activates RAAS pathway to raise blood pressure and stimulate aldosterone release  ○​ aldosterone: increases sodium reabsorption, leading to water retention and reduced urine output ​ Explain the RAAS ○​ regulates blood flow to and within glomerulus ○​ responds to blood pressure and plasma sodium changes ○​ refer to chart on page 19 ​ Describe renal function tests: ○​ Creatinine Clearance: measures how well kidneys remove creatinine ​urine is collected over 24 hours and blood creatinine levels are checked ​low clearance = kidneys aren’t filtering properly ○​ Estimated Glomerular Filtration: measures how well kidneys filter blood ​calculated using blood creatinine levels, age, sex, etc. ​low eGFR = kidney problems (ex. chronic kidney disease) ○​ Cystatin C: protein filtered by kidneys; used to assess kidney function ​alternative to creatinine; less affected by muscle mass ○​ Beta2Microglobulin: protein filtered by kidneys ​high levels = kidney damage (ex. glomerular disease or kidney transplants) ​ Differentiate eGFR and GFR ○​ eGFR is an estimate based on blood creatinine levels and other factors, while GFR is the actual filtration rate of kidneys ○​ eGFR is good for routine screenings, while GFR is more precise and used in specific clinical circumstances ​ Identify factors that can influence eGFR results (age, muscle mass, ethnicity, etc) ○​ older age → lower eGFR ○​ men have higher eGFR than women due to differences in muscle mass ○​ more muscle mass → more creatinine → higher eGFR ○​ black individuals have more muscle mass → higher eGFR Chapter 5: Physical Examination of Urine ​ List the three (3) constituents that give color to normal urine. ○​ eurochrome, uroerythrin, urobilin ​ Compare the effects of hemoglobin, red blood cells, myoglobin, melanin, and homogentisic acid on urine color/clarity. ○​ hemoglobin → clear red ○​ RBCs → cloudy red ○​ myoglobin → red to brown or black ○​ melanin → black ○​ homogentisic acid → gradual darkening ​ Describe how specific gravity is measured in urine. ○​ Refractometer (if applicable): concentration changes velocity and angle where light passes through solution; prism determines angle that light is passing through in urine  and converts angle to calibrated viewing scale ○​ Reagent strip: measures ionic concentration; increased acidity → increased SG ​ Describe what types of solutes/molecules can affect the specific gravity. ○​ glucose and protein / large molecules ​ Define the terms used to describe different densities of urine. ○​ isosthenuric: SG of 1.010 ○​ hyposthenuric: SG lower than 1.010 ○​ hypersthenuric: SG higher than 1.010 ​ State the normal ranges of the osmolality ○​