- Sterile field
- An area created with sterile drapes and supplies around the surgical site; only sterile items and sterile-gowned/gloved persons may contact it.
- Asepsis
- The absence of pathogenic microorganisms. Surgical (sterile) asepsis aims for the total absence of all microbes on the sterile field.
- Surgical conscience
- The professional honesty and self-discipline to maintain sterile technique and report any break in sterility, even when no one else sees it.
- Time-out (Universal Protocol)
- A pause before incision where the whole team verifies correct patient, correct procedure, and correct site/side to prevent wrong-site surgery.
- What is the CST credential?
- Certified Surgical Technologist — the NBSTSA credential for the surgical technologist who prepares the OR and assists during surgery, primarily in the scrub role.
- Sterile to sterile rule
- Only sterile items may touch other sterile items. If a sterile item contacts anything unsterile, it is contaminated.
- 1-inch (2.5 cm) margin rule
- The outer 1 inch around the edge of a sterile drape or wrapper is considered unsterile (the boundary zone).
- Gown sterile zones
- A sterile gown is sterile only from the chest/nipple line to the level of the sterile field (waist) in front, and the sleeves from 2 inches above the elbow to the cuff.
- Why keep hands above waist and in sight?
- Anything below the waist/table level or out of sight is considered unsterile; the sterile field is only chest-to-waist height.
- Strike-through contamination
- Moisture wicking through a drape, gown, or wrapper that carries microbes from an unsterile surface to a sterile one, contaminating it.
- Surgical hand scrub purpose
- Mechanically and chemically removes soil and transient microbes and reduces resident flora on the hands and forearms before gowning and gloving.
- Counted brush-stroke vs timed scrub
- Two accepted surgical scrub methods: a counted number of brush strokes per finger/surface, or a timed scrub (typically 2–5 minutes per facility policy).
- Scrub: hands vs elbows position
- Keep hands above the elbows during and after the scrub so water runs from the cleanest area (fingertips) down toward the elbows.
- Closed gloving
- The preferred self-gloving method: hands stay inside the gown sleeves/cuffs while pulling on gloves, so bare skin never touches the glove's outside.
- Open gloving
- Gloving where fingers protrude through the cuffs; used for procedures not requiring a full gown (e.g., Foley insertion) or to change a single glove.
- Skin antiseptic prep direction
- Prep from the incision site outward in expanding circles toward the periphery — clean to dirty — and never return a used sponge to the center.
- Common skin prep agents
- Chlorhexidine gluconate (CHG), povidone-iodine (Betadine), and alcohol-based preps; CHG has longer residual activity.
- Pooling of prep solution risk
- Alcohol-based preps pooling under drapes are a fire hazard and can cause skin burns; allow full drying before draping/electrosurgery.
- Hair removal at surgical site
- Remove hair only if it interferes with the procedure, using clippers (not a razor) immediately before surgery to reduce skin-nick infection risk.
- Patient identification before surgery
- Verify the patient with at least two identifiers (name + date of birth), the consent, the procedure, and the surgical site/side.
- Supine position
- Lying flat on the back; the most common surgical position, used for abdominal, cardiac, and many general procedures.
- Trendelenburg position
- Supine with the head lower than the feet; used for lower-abdominal/pelvic surgery to shift bowel cephalad. Watch for respiratory compromise.
- Reverse Trendelenburg
- Supine with the head higher than the feet; used for upper-abdominal, head/neck, and thyroid surgery.
- Lithotomy position
- Supine with legs raised and abducted in stirrups; used for gynecologic, urologic, and rectal procedures. Raise/lower both legs together.
- Prone position
- Lying face down; used for spine and posterior procedures. Protect the eyes, face, breasts, and genitalia, and support the chest.
- Lateral (Sims') position
- Lying on one side; used for kidney, hip, and thoracic procedures. Place an axillary roll to protect the brachial plexus.
- Fowler's position
- Sitting/semi-sitting; used for some cranial, shoulder, and nasopharyngeal procedures. Risk of venous air embolism.
- Positioning injury prevention
- Pad bony prominences and nerves, maintain body alignment, avoid pressure on the eyes and genitalia, and protect the brachial plexus and peroneal nerve.
- Most commonly injured nerve in lithotomy
- The common peroneal nerve (from stirrup pressure at the lateral knee/fibular head), causing foot drop.
- Purpose of the safety strap
- A restraint placed ~2 inches above the knees on the supine patient to prevent falls; never so tight it impairs circulation.
- Scrub (sterile) role
- The CST who maintains the sterile field, sets up the back table/Mayo, passes instruments, and tracks counts during the procedure.
- Circulator (non-sterile) role
- The RN/team member outside the sterile field who manages the room, obtains supplies, documents, and assists with counts and patient care.
- Mayo stand
- A small sterile stand placed over the patient holding the instruments in immediate use during the procedure.
- Back table
- The large sterile table holding the bulk of the instruments, sponges, sutures, and supplies organized by the scrub.
- First (initial) count timing
- Sponges, sharps, and instruments are counted by the scrub and circulator before the procedure (baseline), and recorded.
- When are surgical counts required?
- Before the procedure (initial), before closure of a cavity, before wound (skin) closure, and whenever staff is relieved — plus any time counts are in question.
- Action for an incorrect count
- Notify the surgeon, recount, search the field/floor/trash/drapes, and obtain an X-ray if the item is not found; document everything.
- Radiopaque sponge
- Surgical sponges contain a radiopaque marker so a retained sponge shows up on X-ray; never use them as dressings.
- Retained surgical item (RSI)
- A 'never event' — an item (sponge, needle, instrument) unintentionally left in the patient; counts exist to prevent it.
- Neutral / no-touch zone
- A designated tray or magnetic mat for passing sharps hands-free between scrub and surgeon to prevent sharps injuries.
- Scalpel handle / blade pairings
- A #3 handle takes #10, #11, #12, and #15 blades; a #4 handle takes the larger #20–#23 blades.
- #10 blade vs #15 blade
- #10 = a large curved belly for long skin incisions; #15 = a small curved blade for short, precise incisions.
- #11 blade
- A sharp, pointed (stab) blade used for incising abscesses, making arteriotomy/stab incisions.
- Loading a blade safely
- Use a needle holder (not fingers), grasp the dull (non-cutting) edge, and slide the blade onto the handle's groove pointing away from yourself.
- Cutting instruments (examples)
- Scalpels, Mayo scissors (heavy/suture), Metzenbaum scissors (delicate tissue), and bandage scissors.
- Mayo vs Metzenbaum scissors
- Mayo = heavier, for cutting suture and dense tissue; Metzenbaum ('Metz') = lighter and longer, for fine/delicate tissue dissection.
- Grasping/holding instruments
- Forceps (thumb/pickups), Allis, Babcock, Kocher (Ochsner), and tenacula — used to hold or retract tissue.
- Allis vs Babcock
- Allis = teeth that grasp tissue firmly (e.g., to be removed); Babcock = atraumatic, rounded ends for delicate/tubular structures like bowel.
- Hemostatic clamps (occluding)
- Hemostats (mosquito, Crile, Kelly), Rochester-Pean, and right-angle (Mixter) clamps used to clamp bleeding vessels.
- Mosquito vs Kelly vs Crile
- Mosquito = smallest, fine bleeders; Crile = fully serrated jaws; Kelly = partially serrated jaws; size increases mosquito < Crile/Kelly < Pean.
- Needle holder (driver)
- An instrument that grasps and drives a curved suture needle; load the needle 1/2 to 2/3 from the tip, in the holder's jaw tip.
- Retractors: handheld vs self-retaining
- Handheld (Army-Navy, Richardson, Deaver, malleable) held by an assistant; self-retaining (Weitlaner, Balfour, Bookwalter) hold themselves open.
- Probing/dilating instruments
- Probes, grooved directors, and dilators (e.g., Hegar, Bakes) used to explore or enlarge a structure or duct.
- Suction tips
- Yankauer (tonsil) for the oropharynx/large volumes; Poole (with guard) for abdominal cavities; Frazier for delicate neuro/ENT fields.
- Passing instruments to the surgeon
- Pass firmly into the surgeon's palm in the ready-to-use position so they need not look away from the field; pass curved instruments curve-down.
- Box lock
- The hinge joint of a ringed instrument where the two halves cross; inspect and clean it because debris collects there.
- Ratchet
- The interlocking teeth on the finger rings of a clamp/needle holder that lock the jaws closed at set tensions.
- Serrations
- The grooves on instrument jaws that improve grip on tissue or suture; transverse, longitudinal, or cross-hatched.
- Tissue (toothed) vs smooth forceps
- Toothed (rat-tooth/Adson) grip skin/tough tissue; smooth/non-toothed forceps handle delicate tissue (bowel, vessels) atraumatically.
- Sponge stick (sponge forceps)
- A ring forceps holding a folded sponge, used for prepping, blunt dissection, or absorbing fluid in a deep cavity.
- Absorbable suture (examples)
- Surgical gut (plain/chromic), polyglactin 910 (Vicryl), poliglecaprone (Monocryl), polydioxanone (PDS) — broken down by the body over time.
- Non-absorbable suture (examples)
- Silk, nylon (Ethilon), polypropylene (Prolene), polyester, and stainless steel — remain or are removed; used where lasting strength is needed.
- Suture sizing (USP)
- The more zeros, the smaller the suture: 2-0 is larger than 5-0; sizes range from heavy (#5) down to very fine (11-0).
- Monofilament vs multifilament suture
- Monofilament = single strand, less tissue drag and lower infection harbor; multifilament (braided) = stronger handling but more capillarity.
- Tie / ligature / free tie
- A strand of suture used to tie off (ligate) a blood vessel; a 'free tie' is handed without a needle; a 'tie on a passer' is on a clamp.
- Swaged (atraumatic) needle
- A suture permanently attached to the needle (no eye), so a single strand passes through tissue — atraumatic.
- Cutting vs tapered needle
- Cutting needles (sharp edges) for tough tissue like skin/fascia; tapered (round body) needles for soft tissue like bowel and vessels.
- Surgical stapler uses
- Devices that place rows of staples for skin closure, GI anastomosis (GIA/TA/EEA), and ligation — faster than hand-suturing.
- Surgical sponges (types)
- Raytec (4-by-4-inch, radiopaque), laparotomy ('lap') sponges, Kittner/peanut dissectors, and cottonoids (neuro) — all counted.
- Drain purpose (Penrose, JP, Hemovac)
- Drains evacuate blood/fluid from a wound; Penrose = passive; Jackson-Pratt and Hemovac = closed active (suction) systems.
- Electrosurgery (ESU / 'Bovie')
- Uses high-frequency current to cut tissue and coagulate (stop) bleeding; cutting = continuous current, coagulation = intermittent.
- Monopolar vs bipolar electrosurgery
- Monopolar = current flows from the active electrode through the patient to a dispersive (grounding) pad; bipolar = current passes only between the two forceps tips (no pad).
- Dispersive (grounding) pad placement
- Place over clean, dry, well-vascularized muscle close to the site; avoid bony prominences, scars, implants, and hair to prevent burns.
- Surgical smoke (plume) hazard
- Electrosurgery/laser smoke can carry viable cells, viral DNA, and toxins; use a smoke evacuator and high-filtration masks.
- Pneumatic tourniquet purpose
- Creates a bloodless field on an extremity; record inflation pressure and time, and limit time (often up to 60 min upper / 90 min lower limb) to avoid nerve/tissue injury.
- Estimated blood loss (EBL)
- The amount of blood lost during surgery, estimated by weighing sponges, measuring suction canisters, and observing drapes.
- Hemostatic agents (chemical/mechanical)
- Gelfoam, Surgicel (oxidized cellulose), thrombin, bone wax, and microfibrillar collagen — promote clotting at the bleeding site.
- Specimen handling
- Identify, keep correct (often do NOT place gross specimens in formalin until verified), label with patient/site, and hand off to the circulator promptly; never let a specimen dry out unless ordered.
- Frozen section specimen
- A specimen sent fresh (NOT in formalin) for rapid pathology while the patient is still under anesthesia to guide the procedure.
- Culture specimen handling
- Specimens for culture and sensitivity are placed in the appropriate sterile container/medium (aerobic/anaerobic), not formalin.
- Laparoscopy (MIS)
- Minimally invasive surgery through small ports using a camera (laparoscope) and long instruments; the abdomen is insufflated with CO₂.
- Why CO₂ for insufflation?
- Carbon dioxide is noncombustible, highly soluble in blood (so emboli are rare), and inexpensive — used to create pneumoperitoneum.
- Veress needle vs Hasson
- Veress needle = closed insufflation entry; Hasson (open) technique = direct visualized port placement; both establish pneumoperitoneum.
- Trocar
- A sharp/blunt-tipped instrument within a cannula used to puncture the body wall and create a port for laparoscopic instruments.
- Endoscope vs laparoscope
- An endoscope views a hollow organ/cavity through a natural orifice; a laparoscope is the scope used through ports for abdominal MIS.
- Robotic surgery role of the CST
- Sets up sterile instrument arms, drapes the robotic arms, exchanges instruments, and assists at the bedside while the surgeon operates from a console.
- Laser safety
- Wear wavelength-specific eye protection, post warning signs, cover windows, use non-reflective instruments, keep water/saline ready, and protect the airway from ignition.
- C-arm (fluoroscopy) safety
- Wear lead aprons/thyroid shields, increase distance from the source, and minimize exposure time (time, distance, shielding).
- Hemostasis methods (mechanical)
- Pressure, ligatures, suture ligation, clips, staples, bone wax, and tourniquet — physical means to stop bleeding.
- Hemostasis methods (thermal)
- Electrosurgery, laser, argon beam coagulation, and harmonic (ultrasonic) scalpel — use energy to coagulate tissue.
- Surgical wound classification I
- Class I — Clean: uninfected, no inflammation, respiratory/GI/GU/oropharyngeal tracts not entered (e.g., a hernia repair).
- Surgical wound classification II
- Class II — Clean-contaminated: a controlled entry into the respiratory/GI/GU tract without unusual contamination (e.g., elective cholecystectomy).
- Surgical wound classification III
- Class III — Contaminated: open fresh wounds, major break in sterile technique, or gross GI spillage.
- Surgical wound classification IV
- Class IV — Dirty/infected: old traumatic wounds with retained devitalized tissue, or existing clinical infection/perforated viscera.
- First-intention healing
- Primary union: a clean incision with edges approximated (sutured); heals fastest with minimal scarring.
- Second-intention healing
- The wound is left open to heal by granulation from the bottom up (e.g., infected/contaminated wounds); more scarring.
- Third-intention (delayed primary) healing
- A contaminated wound is left open, then sutured/closed after several days once infection risk decreases.
- Dehiscence vs evisceration
- Dehiscence = partial or total separation of wound layers; evisceration = protrusion of viscera (e.g., bowel) through the open wound — an emergency.
- Surgical site infection (SSI) prevention
- Maintain sterile technique, give timely prophylactic antibiotics, normothermia, glucose control, proper hair removal (clippers), and skin antisepsis.
- Dressing purposes
- Protect the wound, absorb drainage, apply pressure/support, maintain a moist healing environment, and provide a barrier to contamination.
- Steps after the procedure (closing)
- Perform the final counts, hand off the specimen, account for sharps, apply the dressing after the drape is removed, and break down the field safely.
- PACU (post-anesthesia care unit)
- Where the patient recovers from anesthesia and is monitored (airway, vitals, level of consciousness) before discharge to a unit or home.
- Breaking down the sterile field
- After the dressing is on, keep gown/gloves until the patient leaves; dispose of sharps in puncture-proof containers and handle instruments to prevent injury.
- OR turnover / terminal cleaning
- Between cases, surfaces and equipment are cleaned/disinfected; terminal cleaning (end of day) is a thorough decontamination of the entire room.
- Malignant hyperthermia (MH)
- A life-threatening reaction to certain anesthetics (volatile agents, succinylcholine): rising end-tidal CO₂, rigidity, tachycardia, and later high fever; treat with dantrolene.
- Dantrolene
- The antidote for malignant hyperthermia; the CST/team helps reconstitute many vials rapidly while the agent is stopped and the patient is cooled.
- Postoperative complications to monitor
- Hemorrhage, shock, SSI, atelectasis/pneumonia, DVT/PE, urinary retention, ileus, dehiscence/evisceration, and nausea/vomiting.
- Hypothermia prevention
- Warm IV fluids/irrigation, forced-air warming blankets, and a warm OR; normothermia lowers SSI and bleeding risk.
- Steri-Strips / skin closure tapes
- Adhesive strips that approximate skin edges, used alone for small wounds or to reinforce a sutured/stapled incision.
- Surgical site verification post-op
- The dressing, drains, and specimen are documented; counts must be correct and recorded before the patient leaves the OR.
- Decontamination
- The first step of instrument processing: cleaning/disinfection to remove blood, debris, and microbes so an item is safe to handle before sterilization.
- Spaulding classification: critical items
- Items entering sterile tissue or the vascular system (surgical instruments, implants) — must be STERILIZED.
- Spaulding: semicritical items
- Items contacting mucous membranes or non-intact skin (endoscopes, laryngoscope blades) — require at least high-level disinfection.
- Spaulding: noncritical items
- Items contacting only intact skin (BP cuffs, OR table) — require low- or intermediate-level disinfection.
- Sterilization vs disinfection
- Sterilization destroys ALL microbial life including spores; disinfection destroys most pathogens but not necessarily all spores.
- Steam (autoclave) sterilization
- Moist heat under pressure (e.g., 250°F/121°C gravity or 270°F/132°C prevacuum) — the most common, economical method for heat/moisture-stable items.
- Why clean before sterilizing?
- Organic debris (blood/protein) shields microbes and prevents the sterilant from contacting all surfaces, so cleaning must precede sterilization.
- Ethylene oxide (EO/EtO) sterilization
- A low-temperature gas method for heat- and moisture-sensitive items; effective but toxic, flammable, and requires lengthy aeration.
- Hydrogen peroxide gas plasma
- A low-temperature method (e.g., Sterrad) for delicate/heat-sensitive items; fast aeration, no toxic residue, but lumen/cellulose limits.
- Peracetic acid sterilization
- A liquid chemical sterilant used for immersible heat-sensitive items like endoscopes; just-in-time, not for long storage.
- Immediate-use steam sterilization (IUSS)
- Formerly 'flash' sterilization for an item needed immediately; minimize its use — items are not packaged for storage and must be used at once.
- Biological indicator (BI)
- A vial of resistant bacterial spores (Geobacillus stearothermophilus for steam) processed and incubated to confirm the sterilizer actually killed spores.
- Chemical indicator (CI)
- A tape/strip/integrator that changes color to show an item was EXPOSED to the sterilant — but does NOT prove sterility (only the BI does).
- Bowie-Dick test
- A daily air-removal/steam-penetration test for prevacuum steam sterilizers, run in an empty chamber before the first load.
- Mechanical indicators
- The sterilizer's gauges/printouts of time, temperature, and pressure that verify the cycle ran within parameters.
- Event-related sterility
- A package stays sterile until an event compromises it (tear, wetness, drop) — not a fixed expiration date — given proper storage.
- Inspecting a sterile package before use
- Check the integrity (no tears/holes/moisture), the chemical indicator change, and the package seal before opening onto the field.
- Loading the sterilizer
- Open box locks/ratchets, place items so the sterilant contacts all surfaces, do not overload, and position basins/cups on edge to drain.
- Peel pack orientation
- Place the package paper-to-paper and plastic-to-plastic, and present so the steam/sterilant can enter — open toward the sterile field for delivery.
- Lumen / cannulated instrument processing
- Flush and brush lumens; some low-temp methods require lumen length/diameter limits or adapters so the sterilant reaches the inside.
- Ultrasonic cleaner
- Uses cavitation (sound-wave bubbles) to remove fine debris from box locks, serrations, and crevices after gross cleaning.
- Instrument lubrication ('milk')
- A water-soluble, steam-permeable lubricant applied to hinged instruments to maintain action and prevent stiffness/spotting.
- Enzymatic cleaner
- A detergent containing enzymes that break down blood, protein, and other organic soil during decontamination.
- Workflow direction in sterile processing
- Move from dirty (decontamination) to clean (prep/pack) to sterile (sterilizer/storage) — never backward — to prevent recontamination.
- PPE in decontamination
- Wear gloves, a fluid-resistant gown, a mask, and eye/face protection because of splash and bioburden when cleaning soiled instruments.
- Wrapping for sterilization (double-wrap)
- Sequential or simultaneous double wrapping (or a rigid container) maintains a sterile barrier and allows aseptic opening.
- Storage of sterile supplies
- Store in a clean, dry, low-traffic area; off the floor, away from vents/sprinklers, with controlled temperature and humidity.
- Prion (CJD) instrument handling
- Prions resist standard sterilization; use special extended protocols, single-use items when possible, or destruction per policy for suspected CJD.
- Care of powered/pneumatic instruments
- Do not immerse motors unless rated; clean, lubricate, and test drills/saws per manufacturer instructions for use (IFU).
- Manufacturer IFU importance
- Always follow the device manufacturer's instructions for use for cleaning, lubrication, and the validated sterilization method/parameters.
- Anatomical position
- The reference posture: standing erect, facing forward, arms at sides, palms forward — used to describe all directional terms.
- Superior vs inferior
- Superior = toward the head (upper); inferior = toward the feet (lower).
- Anterior (ventral) vs posterior (dorsal)
- Anterior = toward the front of the body; posterior = toward the back.
- Medial vs lateral
- Medial = toward the midline; lateral = away from the midline (toward the side).
- Proximal vs distal
- Proximal = closer to the trunk/point of attachment; distal = farther from it (e.g., the wrist is distal to the elbow).
- Sagittal / coronal / transverse planes
- Sagittal = divides left/right; coronal (frontal) = divides front/back; transverse (axial) = divides top/bottom.
- Four abdominal quadrants
- RUQ, LUQ, RLQ, LLQ — divided by lines through the umbilicus; locate organs (e.g., appendix in the RLQ).
- Layers of the abdominal wall (incision order)
- Skin → subcutaneous (Camper's/Scarpa's fascia) → muscle/fascia (rectus/external oblique) → transversalis fascia → preperitoneal fat → peritoneum.
- Pericardium / pleura / peritoneum
- Serous membranes lining cavities: pericardium (heart), pleura (lungs), peritoneum (abdominal cavity).
- Layers of the GI tract wall
- Mucosa → submucosa → muscularis (externa) → serosa (or adventitia) — from lumen outward.
- Chambers of the heart
- Right atrium, right ventricle, left atrium, left ventricle; the right side pumps to the lungs, the left side to the body.
- Heart valves
- Tricuspid (RA→RV), pulmonary (RV→lungs), mitral/bicuspid (LA→LV), aortic (LV→body) — keep blood flowing one way.
- Coronary arteries
- The right and left coronary arteries (LAD, circumflex branches) supply the heart muscle itself.
- Path of blood through the lungs
- RV → pulmonary artery → lungs (oxygenated) → pulmonary veins → left atrium (pulmonary circulation).
- Layers of the GI: stomach to anus order
- Esophagus → stomach → duodenum → jejunum → ileum → cecum → colon (ascending, transverse, descending, sigmoid) → rectum → anus.
- Accessory digestive organs
- Liver, gallbladder, and pancreas — produce/store bile and enzymes that aid digestion.
- Biliary tree (gallbladder surgery anatomy)
- Bile flows: liver → hepatic ducts → common hepatic duct; gallbladder → cystic duct → common bile duct → duodenum (via ampulla of Vater).
- Calot's (cystohepatic) triangle
- The landmark in cholecystectomy bounded by the cystic duct, common hepatic duct, and liver; the cystic artery runs within it.
- Urinary system organs
- Kidneys → ureters → bladder → urethra; the kidneys filter blood and form urine (nephron is the functional unit).
- Layers of the meninges
- Dura mater (outer), arachnoid (middle), pia mater (inner) cover the brain and spinal cord; CSF sits in the subarachnoid space.
- Female reproductive anatomy
- Ovaries → fallopian tubes → uterus → cervix → vagina; relevant to hysterectomy, salpingectomy, and oophorectomy.
- Male reproductive anatomy
- Testes → epididymis → vas deferens → seminal vesicles/prostate → urethra; relevant to vasectomy, prostatectomy, and orchiectomy.
- Long bone structure
- Diaphysis (shaft), epiphysis (ends), metaphysis, periosteum (outer membrane), and medullary cavity (marrow).
- Bones of the forearm / lower leg
- Forearm: radius (lateral, thumb side) and ulna (medial). Lower leg: tibia (shinbone) and fibula (lateral).
- Eye anatomy (key layers)
- Cornea, anterior chamber, iris/pupil, lens, vitreous, retina; relevant to cataract and retinal surgery.
- Ear divisions
- Outer (auricle, canal), middle (ossicles: malleus, incus, stapes; tympanic membrane), inner (cochlea, vestibule); relevant to myringotomy.
- Respiratory tract structures
- Nose → pharynx → larynx → trachea → bronchi → bronchioles → alveoli (site of gas exchange).
- Tissue types
- Epithelial (covers/lines), connective (supports, e.g., bone/blood), muscle (contracts), and nervous (transmits impulses).
- Homeostasis
- The body's maintenance of a stable internal environment (temperature, pH, fluid/electrolyte balance) despite external changes.
- Endocrine glands of surgical interest
- Thyroid and parathyroids (neck), adrenal glands (atop kidneys), pituitary (brain), and pancreas (islets) — sites of common procedures.
- Microorganism
- A microscopic living organism — bacteria, viruses, fungi, protozoa, and prions are the groups relevant to surgical infection control.
- Bacterial shapes
- Cocci (spheres), bacilli (rods), and spirilla/spirochetes (spirals); arrangements include strepto- (chains) and staphylo- (clusters).
- Gram-positive vs Gram-negative
- Gram-positive bacteria stain purple (thick peptidoglycan wall); Gram-negative stain pink/red (thin wall + outer membrane). Guides antibiotics.
- Staphylococcus aureus / MRSA
- A Gram-positive cluster-forming cocci; a leading SSI cause. MRSA is methicillin-resistant and requires contact precautions.
- Bacterial spores
- Dormant, highly resistant forms (e.g., Clostridium, Bacillus) that survive heat/chemicals; sterilization must kill spores.
- Clostridioides difficile / C. tetani
- Spore-forming anaerobes: C. difficile causes colitis (needs soap-and-water hand washing); C. tetani causes tetanus.
- Aerobic vs anaerobic bacteria
- Aerobes require oxygen; anaerobes grow without it (and many are killed by oxygen) — affects culture method and antibiotic choice.
- Pseudomonas aeruginosa
- A Gram-negative aerobic rod, common in moist environments; an opportunistic SSI and burn-wound pathogen.
- Pathogen vs normal flora
- A pathogen causes disease; normal flora are resident microbes that are usually harmless but can cause infection if displaced (e.g., gut flora in the peritoneum).
- Chain of infection
- Agent → reservoir → portal of exit → mode of transmission → portal of entry → susceptible host; breaking any link prevents infection.
- Modes of disease transmission
- Contact (direct/indirect), droplet, airborne, vehicle (food/water/blood), and vector — guide isolation precautions.
- Standard precautions
- Treat all blood and body fluids as potentially infectious: hand hygiene, gloves, gowns, masks/eye protection, and safe sharps handling for every patient.
- Bloodborne pathogens (HBV, HCV, HIV)
- Viruses transmitted via blood/body fluids; the main occupational risk after a needlestick — follow exposure protocol and report immediately.
- Most common SSI organisms
- Staphylococcus aureus (incl. MRSA), coagulase-negative staph, Enterococcus, E. coli, and Pseudomonas.
- Virus vs bacterium
- A virus is an acellular particle that must replicate inside a host cell (not killed by antibiotics); a bacterium is a single-celled organism.
- Fungi of surgical concern
- Yeasts (Candida) and molds (Aspergillus) cause opportunistic infections, especially in immunocompromised patients.
- Nosocomial (healthcare-associated) infection
- An infection acquired in a healthcare setting (e.g., SSI, CAUTI, CLABSI, VAP) not present on admission.
- Hand hygiene importance
- The single most effective measure to prevent the spread of infection; use alcohol-based rub or soap-and-water (soap for spores like C. diff).
- Resident vs transient flora
- Resident flora live deep in skin layers (hard to remove); transient flora sit on the surface and are removed by handwashing/scrub.
- Endogenous vs exogenous infection source
- Endogenous = from the patient's own flora; exogenous = from an outside source (staff, instruments, environment).
- Pharmacology: generic vs trade name
- Generic = the official nonproprietary drug name (lowercase); trade/brand = the manufacturer's name (capitalized), e.g., epinephrine vs Adrenalin.
- Routes of medication administration
- Topical, oral (PO), IV, IM, subcutaneous, intrathecal, and on-field instillation/irrigation; the CST handles many drugs ON the sterile field.
- Medication labeling on the sterile field
- Label EVERY medication, container, and solution on the field immediately (even one), and verify the drug, strength, and expiration aloud with the circulator.
- Local anesthetics (examples)
- Lidocaine, bupivacaine (Marcaine), and procaine — block nerve conduction for local/regional anesthesia; lidocaine onset is fast, bupivacaine lasts longer.
- Why add epinephrine to a local anesthetic?
- Epinephrine causes vasoconstriction, which prolongs the anesthetic's action and reduces bleeding — but avoid in end-arteries (fingers, toes, nose, penis).
- General vs regional vs local anesthesia
- General = unconscious, whole-body; regional = a region numbed (spinal, epidural, block) with the patient awake; local = a small area numbed.
- Anesthetic agent classes (general)
- Inhalation agents (sevoflurane, desflurane, nitrous oxide) and IV agents (propofol, ketamine, etomidate); muscle relaxants paralyze for intubation.
- Neuromuscular blockers
- Depolarizing (succinylcholine — fast, short) and non-depolarizing (rocuronium, vecuronium) relax muscles; succinylcholine can trigger MH.
- Common surgical irrigation fluids
- Normal saline (0.9% NaCl) and sterile water; warmed for normothermia. Choice depends on the tissue (e.g., not water near open vessels due to hemolysis).
- Heparin (intraoperative use)
- An anticoagulant used on the field (e.g., vascular cases) to prevent clotting; its reversal agent is protamine sulfate.
- Protamine sulfate
- The reversal agent for heparin; given to neutralize anticoagulation (e.g., after vascular/cardiac procedures).
- Thrombin (topical)
- A topical hemostatic agent applied to a bleeding surface to promote clotting; never inject it intravascularly.
- Contrast media
- Radiopaque dyes (e.g., for cholangiography) injected to visualize ducts/vessels on fluoroscopy; ask about iodine/shellfish allergy.
- Surgical dyes/stains
- Methylene blue, gentian violet, and indigo carmine — mark tissue/margins or identify structures (e.g., methylene blue for leaks).
- Antibiotic irrigation/prophylaxis
- Prophylactic antibiotics (often a cephalosporin like cefazolin) are given before incision; antibiotic irrigation may be used on the field per surgeon.
- Drug measurement / dosage basics
- Use the metric system: 1 g = 1,000 mg, 1 mg = 1,000 mcg, 1 L = 1,000 mL; percent solution = g of drug per 100 mL.
- Reading a 1% lidocaine concentration
- 1% = 1 g per 100 mL = 10 mg/mL; so a 10 mL vial of 1% lidocaine contains 100 mg.
- Six rights of medication
- Right patient, right drug, right dose, right route, right time, and right documentation — confirmed when handling drugs on the field.
- Controlled substances
- Drugs with abuse potential (e.g., opioids) are scheduled (C-II to C-V), tracked, counted, and witnessed for waste per DEA/facility policy.
- Drug allergy verification
- Confirm allergies (latex, iodine, medications) before prep/anesthesia; communicate them to the team and document.
- AST role vs NBSTSA role
- AST (Association of Surgical Technologists) is the professional association; NBSTSA (National Board of Surgical Technology and Surgical Assisting) develops and awards the CST credential.
- CST eligibility
- Graduation from a surgical technology program accredited by CAAHEP or ABHES qualifies a candidate to sit for the CST exam.
- CST recertification
- Maintain the CST by earning continuing education credits over a multi-year cycle (commonly 60 CE credits over 4 years) or by re-examination.
- Informed consent responsibility
- The surgeon (provider) is responsible for obtaining informed consent; the team verifies it is signed, complete, and matches the planned procedure/site.
- Chain of command
- Report concerns through the proper line (charge nurse, supervisor, manager); the CST escalates patient-safety or sterility issues appropriately.
- Scope of practice (CST)
- Practice within the legally and facility-defined CST role; do not perform tasks outside training/credentialing (e.g., independent prescribing or surgeon-only acts).
- Documentation accuracy
- Counts, implants (with lot/serial), specimens, medications, and equipment used must be documented accurately and legibly in the operative record.
- HIPAA / patient confidentiality
- Protect patient health information; discuss cases only with the care team and only as needed for care.
- OR attire / restricted areas
- Wear clean surgical attire, cover all hair, and don a mask in restricted areas; traffic and door openings increase contamination risk.
- Preference card
- A surgeon-specific record of preferred instruments, supplies, sutures, gloves, and setup for a given procedure — used to pull the case.
- Implant handling and documentation
- Verify size/type, keep implants sterile, and record the manufacturer, lot/serial number, and expiration in the operative record for traceability.
- OSHA in the OR
- Sets workplace safety standards (bloodborne pathogens, hazard communication, sharps safety, surgical smoke) to protect staff.
- Fire triangle in the OR
- Fuel (drapes, alcohol prep, hair), oxygen (O₂-enriched field), and ignition (ESU, laser) — control all three to prevent OR fires.
- Latex allergy precautions
- Use latex-free gloves and supplies, schedule the case first (lowest airborne latex), and post signage to prevent anaphylaxis.
- Inventory and supply management
- Maintain par levels, rotate stock by expiration (FIFO), and restock case carts so supplies are available and unexpired.
- Aseptic technique vs sterile technique
- Aseptic technique = practices that reduce contamination broadly; sterile technique = the strict practices that keep a defined field free of all microbes.
- Opening sterile supplies
- Open the far flap first, then the sides, then the near flap toward yourself; never reach over the sterile field or turn your back to it.
- Pouring solution onto the sterile field
- The circulator pours from the edge into a basin held by the scrub (or at the field's edge) without splashing or reaching over the field.
- Once sterile setup is open, keep it sterile
- Keep sterile setups continuously monitored; an unattended or covered field is considered contaminated.
- Draping the patient
- Apply drapes from the incision site outward; once placed, do not move drapes toward the field — only away — and never reposition a dropped drape.
- Vital signs (normal adult ranges)
- HR ~60–100/min, RR ~12–20/min, BP ~120/80 mmHg, temp ~98.6°F/37°C, SpO₂ at least 95% — baseline patient monitoring values.
- Capnography (EtCO₂)
- Continuous end-tidal CO₂ monitoring confirms ventilation and tube placement; a sharp rise is an early sign of malignant hyperthermia.
- Pulse oximetry (SpO₂)
- A noninvasive measure of arterial oxygen saturation; normal is at least 95%; falling values signal hypoxemia.
- Shock (perfusion failure)
- Inadequate tissue perfusion; types include hypovolemic (blood/fluid loss), cardiogenic, distributive (septic/anaphylactic), and obstructive.
- Signs of intraoperative hemorrhage
- Rising heart rate, falling blood pressure, increasing blood in suction/sponges, and a tense/expanding field — alert the surgeon and prepare hemostatic supplies.
- Anaphylaxis intraoperatively
- A severe allergic reaction (latex, drugs, contrast): hypotension, bronchospasm, hives, and edema; treated with epinephrine — keep it available.
- DVT prophylaxis in surgery
- Sequential compression devices, early mobilization, and anticoagulants reduce deep vein thrombosis and pulmonary embolism risk.
- Foley catheter purpose
- An indwelling urinary catheter drains and measures urine during long procedures; inserted with sterile technique to prevent CAUTI.
- Nasogastric (NG) tube
- A tube from nose to stomach to decompress the GI tract or remove contents; used in many abdominal procedures.
- ESU return-pad alarm
- If the electrosurgical unit alarms or won't activate, check the dispersive pad contact and connections before increasing power, to avoid burns.