Lab Safety Protocols

Lab Safety Essentials

• Biological hazards involve potentially harmful organisms and require breaking the chain of infection.
• Key components of infection prevention include source control, transmission interruption, and protecting susceptible hosts.
• The infectious agent, reservoir, and exit portal are the first three components in the chain of infection.
• Transmission can occur via inhalation, ingestion, direct inoculation, or skin contact.
• PPE use, proper handwashing, and waste disposal are critical in preventing infection.
• Hand hygiene is key, using soap and water when visibly soiled or alcohol-based rubs when not.
• Dispose urine by pouring down a laboratory sink, avoid splashing, and then flush with water.
• Chemical spills first aid is best provided by flushing the affected area with water for 15 minutes, and then see medical attention.
• To avoid sudden splashing and explosion, always add acid to water very carefully.
• The NFPA system classifies hazards, with severity ranging from 0 to 4, using a color-coded diamond.
• The "You Were Born Right" mnemonic helps remember the NFPA diamond colors: Yellow, White, Blue, Red.

Hazard Type and Waste Management

• Sharp hazards include needles and broken glassware, requiring disposal in puncture-resistant containers.
• Report accidental needle-sticks to a supervisor immediately after it has happened.
• Exposure to radioactivity during pregnancy poses risks to the fetus, requiring caution with radioactive materials.
• Keep used radioactive material in a secured, marked location until it reaches background levels after 10 half-lives.
• Do not operate electrical equipment with wet hands.
• Ground all electrical equipment to prevent shocks.

Fire Safety Protocols And Guidelines

• Store flammable chemicals properly to prevent fire hazards.
• Smother burning clothes with a blanket.
• Participate regularly in fire drills.
• Remember the RACE protocol: Rescue, Alarm, Contain, and Extinguish/Evacuate.
• Use a fire extinguisher with the PASS technique: Pull, Aim, Squeeze, Sweep.
• Different fire types (A, B, C, D, E, K) require specific extinguishers.
• General precautions include avoiding running, watching for wet floors, lifting properly, and wearing appropriate attire.

Kidney Function

• The kidney regulates fluid balance and waste excretion.
• Kidney size measures 12.5 cm x 6 cm x 2.5 and weigh up to 150g (length, width, depth).
• Urine is a kidney fluid biopsy product that indicates the functional status of the body

Nephron Function And Urine Formation

• The nephron, with approximately 1 to 1.5 million in each kidney, drives kidney function.
• The nephron has glomerulus and tubules that facilitate urine formation step by step.
• Glomerulus is the initial filtration site for the filtration of blood for removal of waste.
• Total renal blood flow into the kidney for processing by the nephrons is 1200 mL/min
• Total renal blood flow of plasma into the kidney for processing by the nephrons is 600-700 mL/min
• The order of passage through the nephron is
  • Glomerulus
  • PCT
  • Loop of Henle
  • DCT
  • Collecting Duct.
• Blood flow pathway in kidney is
  • Renal artery
  • Afferent arteriole
  • Glomerulus
  • Efferent arteriole
  • Peritubular capillaries
  • Vasa recta
  • Renal vein.
• Glomerulus is a selective filter that sieves based on molecule size with molecular weight <70,000 daltons, and charge.
• Albumin with molecular weight of 69,000 daltons cant pass through the glomerulus because it has a negative charge

Tubular Reabsorption and Secretion

• Proximal convoluted tubule or PCT is the primary reabsorption area that reabsorbs 65% of filtrate.
• It selectively reabsorbs substances, and it reabsorbs salts, water, glucose, amino acids, and urea.
• PCT, Loop of Henle, DCT and CD all alter the urine concentrations.
• Renal concentration processes begin in the descending and ascending portions of the Loop of Henle.
• Ascending Loop of Henle reabsorbs “ASIN” salt), but NOT water.
• Vasopressin or Anti-diuretic hormone (ADH) regulates distal convoluted tubule (DCT) and collecting duct (CD) for water reabsorption
• Aldosterone enables sodium reabsorption and affects Blood Pressure
• H+ ions are secreted in exchange for Na+ ions, which are reabsorbed with HCO3-into the plasma.

Renal Function Tests

• Clearance tests measure the rate to remove a filterable substance from the blood.
• Creatinine clearance formula is UV/P x 1.73m^2/A
• Creatinine is the most common substance to evaluate glomerular filtration rate or GFR.

Urine Collection Methods and Urinalysis

• Urine collected from patients can reveal clinical and laboratory findings.
• The urine wheel was the first illustrated medical book that uses color and other macroscopic features to make a diagnosis.
• Hindu physicians determined that "honey urine" attracted ants to indicate diabetes (historically).
• A Normal Urine composition is water (95-97%) and solids including Urea (major), creatinine (also), chloride (greater than sodium greater than potassium or NaCl principal salt
• A typical urine specimen Types include Random, First Morning, Second morning/Fasting, 2-hour post-prandial, Glucose tolerance test and Midstream clean-catch.
• A minimum of 12 mL specimen is required for urine routine examination
• Patient instructions include thoroughly cleansing before providing midstream clean-catch specimen
• The Ideal preservative does not exist because of multiple potential analytes.
• Refrigeration is a good preservative method as it does not interfere but must bring to room temperature
• Changes occurring when testing not done immediately - Increase pH, Odor, Nitrite and Decrease - glucose, ketones, bilirubin, cells and casts.

Macroscopic Examinations

• Color and turbidity are assessed to get a general idea, normal shades are colorless to dark yellow and transparent
• Urine concentration is affected by hydration.
• A Rough indicator of the degree of hydration correlates with urine specific gravity S.G.
• Abnormal finding of Red or Red brown may commonly point to a health issue.
• Report amount of the substances (such as cells and or casts that are often found that lead to pathological factors) as Rare, Few or Moderate or Many.
• Determine urine clarity and record S.G
• Protein level indicates the degree of hydration

Microscopic Quantitations

• To determine the level of cells and cast quantity, first transfer 10-15 mL of urine into a centrifuged tube, for a 5 minute spin
• Next, transfer 20 micro liters of sentiment into glass slide with a dimension of 22X 22mm and examine with a microscope that first uses low power first.

Types of Urine Sediment

• Cells may sediment; look to the red, white, and epithelial cells .
• As a reminder, true Urinary tract infection means bacteria and White blood cells.
• Transudates appear with few bacteria and White blood cells -A minimum of > 2 RTE cells indicates possible tabular injury.

Types of casts

• Csts will feature,
  • A High Power Field of examination and must be counted with a trained eye
  • a matrix, a formation area in the Distal Convoluted and Collecting area only, and a normal of 2 casts / LPF
  • These will take stains like HTH Protein, which is mostly made of Uromodulin, is most reliable.
• Hyaline Cast is normal if found, for its a prototype with . < 2/ LPF, strenuous conditions may change the case.

Crystal Abnormalities

• Crystals will be described to report with terms ranging from none to many -Normal acid and alkali crystals that feature are Amorphous (Urates, Phosphates), Oxalates, Uric and Triple and Calcium
• Alkaline urine levels help differentiate by causing cell's lyses (lysis).

Other Abnormalities

Other Abnormal elements in the urine feature . -Yeast, mucus (threads of low-Refractive Index) and others like Protozoa.

Urine Automated Readers

• These Readers measure strip on light, not by hand on sight!

Blood, Leukocyte, Nitrite, Glucose.

-High glucose in blood can lead to High Glucose in Urin

• The above automated result, will result from poorly processed results.

Quality control

• Quality control (QC) must always be prioritized for each test.

Urine Abnormalities with color changes

• Porphyria will result in Purple to Dark red -Malignancy will result in dark colors.

Specific Anolytes

Specific anolytes and instruments, help create certain detection factors, and more!

• Please Note, The document included will end at pg 155. All this has helped build a foundational step.
• It is more than just a collection vessel and can allow results to be measured with precision and more!