antiseptics and disinfectants Flashcards
what is considered critical risk for transmitting infection?
items enters a sterile area of the body or vascular system; condition at time of use is sterile
what is semi-critical risk?
items that come in contact with mucous membranes; condition at time of use is sterile or high level disinfection
what is non-critical risk?
items that do not come in contact with patient or touch intact skin only; condition at time of use is clean and intermediate or low level disinfection
describe environmental surfaces
medical equipment and housekeeping surfaces; should be clean and intermediate or low level disinfection
define an antiseptic
an agent applied to living tissue to kill or prevent growth of microorganisms
define disinfectant
an agent or treatment applied to an inanimate surface to destroy most microorganisms or viruses, but not spores
define sterilization
the process that kills or removes all types of microorganisms, including spores, fungi, and viruses
*most effective method
define pasteurization
the process of killing microorganisms, other than spores, with hot water or steam at 65-100 degree C (55-75 degree C)
define sanitization
decreasing the number of microorganisms on an inanimate surface to acceptable for public health purposes
describe alcohols
- antiseptic
- ethanol
what are limitations of alcohols?
- no residual effect d/t rapid evaporation (doesn’t stay on amount of time needed for action)
- flammable (cautery, laser- make sure area is completely dry, no pooling in umbilicus or around sides)
- damaging if used on corneal tissue
- if immunosuppressed used betadine swab
what are advantages of alcohols?
- useful when sinks with running water and soap not available
- can also be used as a disinfectant
describe quaternary ammonium compounds
- antiseptic, Zephiran
- red
- rapid onset
- more effective when in tincture with alcohol
- target bacteria (gram + and -), many fungi and viruses
what are limitations of quaternary ammonium compounds?
- no effect on mycobacterium tuberculosis
- CDC found growth of pseudomonas, other gram - bacteria in solutions; DONT use as antiseptic
- absorption by polyethylene and polypropylene of instruments (specifically endoscopes)
describe chlorhexidine
-Hibiclens; 4% hand scrub
what are limitations of chlorhexidine?
- neural toxicity (if used before breaking skin for epidural, spinal, or plexus block)
- causes sensorineural deafness if used with middle ear surgery
what are advantages of chlorhexidine?
- rapid onset (yet slower than alcohols)
- residual effect (works even after dry)
- minimal risk of contact sensitivity (good for plastic surgery)
- not readily absorbed via topical application
describe iodine
- most active antiseptic for intact skin
- 1% solution kills 90% of bacteria in 90 seconds
- 5% solution kills 90% of bacteria in 60 seconds
- target bacteria (gram +/-), viruses, spores (if left wet for 15 min.)
what are limitations of iodine?
- burns with > 7% solution
- hypersensitivity reactions
- staining of clothes, skin (yellowish tint)
describe iodophors
- providone-iodine, Betadine
- antiseptic
- complex of iodine with a carrier agent
- retains the activity of iodine (10% solution has 1 % iodine so kills 90% bacteria in 90 sec.)
- target: bacteria (>90%), mycobacteria, fungi, and lipid-containing viruses, sporicidal with prolonged exposure
what are limitations of iodophors?
- lack persistent effect of chlorhexidine
- bacteria returns in 6-8 hours
- many people may be sensitive and leaves rash if left on
- if > 50 ml of Betadine injected (like with thoracotomy), can cause blindness d/t absorption of iodine
what are advantages of iodophors?
- less irritating than iodine
- broader spectrum than chlorhexidine, same onset
- minimal staining of skin
describe hexachlorophene (pHisoHex)
- decreased bacteria by only 30-50% initially, but continues to decrease down to 4% an hour later
- target: bacteria (especially gram +)
- no effect on spores
what are limitations of pHisoHex?
- daily bathing of neonates lead to brain damage
- absorbed can cause neurotoxic effects, cerebral irritability
- don’t use routinely if pregnant
describe formaldehyde
- disinfectant
- 2-8% solutions used on surgical instruments
- broad spectrum against bacteria, fungi, and viruses
- takes 2-4 days to kill spores
- 4% embalming does not kill mycobacteria
- pungent odor, irritating to respiratory mucosa
describe glutaraldehyde
- more rapid than formaldehyde
- kills bacteria, spores, fungi, viruses
- effects m. tuberculosis
- less pungent and irritating
- better than iodophors and hexachlorophene in sterilizing endoscopes
describe pasteurization
- destroying microorganisms by hot water disinfection (55-75 degree C)
- kills bacteria “of significance in human disease” (gram - rods, m. tuberculosis, many fungi, and viruses)
- may melt equipment
- cost effective
describe silver nitrate
- bactericidal, especially for gonococci (eye gtts in neonates)
- used for cauterizing wounds
- used for burn treatment
what are limitations of silver nitrate?
- hypochloremia with burns (silver binds Cl-)
- hyponatremia also (Na+ follows Cl-)
describe ethylene oxide
- antimicrobial to ALL organisms at room temp
- alternative to heat sterilization (option for materials that will melt)
- special chamber to allow continuous contact of gas with item for several hours
- allow airing to remove residual
- irritation and allergic reactions possible
- associated with latex allergy, spina bifida
