Lecture 1: Aseptic technique and surgical site infection

Question 1

Difference between prophylactic antibiotic and therapeutic antibiotic

Answer 1

Prophylactic given before contamination or infection, therapeutic given to combat existing infection

Question 2

define contamination

Answer 2

presence of microorganisms on a surface, not invading tissue

Question 3

define infection

Answer 3

invasion and replication of microorganisms within tissue- causing pathological issue

Question 4

define antiseptic

Answer 4

substance that prevents or arrests growth of microorganisms, substance is applied to living tissue

Question 5

Define asepsis

Answer 5

prevention of contact with microorganisms

Question 6

define disinfectant

Answer 6

chemical or physical agent that destroys microorganisms but not spores, substance is applied to inanimate objects, decreases microorganism load

Question 7

define sterilization

Answer 7

process used to render a product free of all microorganisms (instruments)

Question 8

what is surgical site infection

Answer 8

infection that occurs after surgery in part of the body where surgery took place

Question 9

why do we care about infection

Answer 9

increase patient morbidity (pain, inflammation, delayed healing), patient mortality, increased hospitalization, client dissatisfaction, increased cost

Question 10

__% incidence of SSI infection across all surgical types

Answer 10

%5

Question 11

__% infection in orthopedic procedures

Answer 11

7%

Question 12

__% infection in dirty vs __% in clean procedures

Answer 12

18%, 2.5%

Question 13

what are the 3 determinants of infection

Answer 13

1. Microbial pathogens (level of virulence, # of pathogens)
2. Local wound environment (necrotic tissue, absent skin barriers)
3. Host defense mechanisms (immunocompromised, age)

Question 14

what is the goal of aseptic surgery

Answer 14

reduce the level of bacteria in surgical wound to one that the patients immune system can control

Question 15

What factors influence infection risk by either increasing microbes or decreasing immune system

Answer 15

1. Duration of procedure
2. Type of procedure
3. Patient preparation
4. Surgeon preparation
5. Instrument sterilization

Question 16

risk of infection __for every hour of surgery

Answer 16

doubles

Question 17

Anesthesia longer than 4hrs infection risk increases by __% for each minute

Answer 17

2%

Question 18

orthopedics surgery typically have higher incidence of infection due to __

Answer 18

implant/foreign object, increased risk for glove perforation, thermal necrosis

Question 19

what surgical locations have higher incidence infection

Answer 19

anus, ear, digits

Question 20

what is the description for clean surgery

Answer 20

Non-traumatic, elective, no acute inflammation, no break in aseptic technique, GI, GU, or resp tract not entered

Question 21

what are some examples of clean surgeries

Answer 21

exploratory laparotomy, elective neuter, TPLO

Question 22

what is the description for clean- contaminated surgery

Answer 22

1. Controlled entry into GI, GU or resp
2. Minor break in aseptic technique
3. Clean wound with drain placement

Question 23

what are some examples of clean contaminated surgeries

Answer 23

entertomy, cystotomy, hysterectomy

Question 24

what is the description for contaminated surgery

Answer 24

fresh traumatic wounds <4hrs old, spillage from GI or UG tract, major break in aseptic technique

Question 25

what are some examples of contaminated surgeries

Answer 25

bile spillage from cholecystectomy, lacerations

Question 26

what is the description for a dirty/infected surgery

Answer 26

old traumatic wounds >4hrs old, devitalized tissue, perforated viscous encountered, purulent exudate, abscesses

Question 27

what are some examples of dirty/infected surgeries

Answer 27

peritonitis from FB, ruptured gallbladder, bullae osteotomy for otitis media

Question 28

patient is __source of microorganisms

Answer 28

endogenous

Question 29

what causes the most wound infections

Answer 29

patients

Question 30

what are the most common pathogens on skin

Answer 30

gram positive staphylococci, anaerobes, gram negative enteric near anus

Question 31

what pathogens located in upper GI

Answer 31

gram + cocci, enteric gram - bacilli, anaerobes

Question 32

what pathogens located in lower GI

Answer 32

enteric gram - bacilli, anaerobes

Question 33

what pathogens located in urogenital tract

Answer 33

E. Coli, streptococcus, anaerobes

Question 34

surgeons, instruments and OR preparation are __sources of microorganisms

Answer 34

exogenous

Question 35

local wound environment has impact on ability of bacteria to __

Answer 35

establish infection

Question 36

good blood supply to local wound allow recruitment of ___ and proper signaling to __

Answer 36

WBC, immune system

Question 37

tissue trauma __# of bacteria required to produce infection

Answer 37

lowers

Question 38

what things negatively affect local wound environemnt

Answer 38

1. Surgical materials- act as FB 2. Wound ischemia 3. Surgeons technical skill

Question 39

how do surgical materials negatively impact wound environment

Answer 39

harbor bacteria and shield them from host defenses Bacteria produce biofilm that adheres to foreign material and protects bacteria

Question 40

describe how biofilm protects bacteria

Answer 40

1. Bacteria release proteins and polysaccharide molecules that adhere to implant 2. Bacteria then adhere to this film via fibronectin 3. Film protects bacteria from host and antibiotic defenses

Question 41

how can shock/trauma cause increase risk for infection

Answer 41

decreased O2, change in pH, necrotic tissue= all support bacterial formation

Question 42

What are halsted principles

Answer 42

1. Minimize tissue trauma 2. Control hemorrhage (hematoma= nidus for infection) 3. Preserve blood supply 4. Strict asepsis 5. Minimize tissue tension 6. Appose tissue accurately (maintains barriers) 7. Eliminate dead space

Question 43

what are the rules of aseptic technique

Answer 43

1. Surgical members remain within sterile area 2. Talking to minimum 3. Non-scrubbed personnel do not reach over sterile field 4. Scrubbed team members face each other and sterile field at all times 5. If sterility of an item is question it is considered contaminated 6. Sterile tables are sterile only at table height 7. Gowns are sterile from mid-chest to waist and from gloved hand to 2 inches above elbow