chapter 7 - preventing perioperative disease transmission (section 1) Flashcards

**invisible to the naked eye, they can be nonpathogenic and parasitic life forms.

**converts matter into simple forms through decay converting them to higher forms that can be used as nutrients.

relationship between microorganisms (indigenous flora) and humans

categories of symbiosis

microbes that live on the skin an inside the human body. They include bacteria, fungi, viruses, and protozoa

*harmless unless given the chance to enter the body through a surgical wound"

multiplication of organisms in the tissues of a host

*may affect not only a patient but also any individual who has contact with the health care facility, including health care workers and visitors

any infection that develops while a patient is in the health care facility

**a broadened categorization - termed HAI (health care-associated infections)

25% not evident until after discharged from hospital

both organisms benefit from and depend on one another to a certain extent.

escherichia coli (E coli)- colonizes within the human intestine, obtains nutrients from the food that humans eat. Produces vitamin K for blood-clotting.

one organism benefits but second organism neither benefits nor is harmed.

indigenous microflora is an example

subcategory of commensalism - two organisms occupy the same area with no effect on each other

subcategory of commensalism - one microorganism inhibits or interferes with the growth of another

example: a microbe produces waste products that are toxic to the neighboring microbes

in commensalism symbiosis the second organism is usually neither benefited or harmed. To a certain extent the second organism can be benefited if the organism is taking up space and preventing other potentially harmful microbes from colonizing.

one organism benefits and the host is harmed

examples: intestinal worms, nosocomial infections (UTI), and airborne viruses (common cold)

** commensal symbiosis can change to parasitism if the microbe becomes opportunistic by entering through a surgical skin incision

microorganisms that cause an infection

#1 nosocomial infection (HAI) - 32%

22% of HAI

15% of HAI

14% of HAI

a group of how all living cells are classified - cellular structure is complex.

includes: protozoa, fungi, green, brown, and red algae, and all plant and animal cells

a group of how all living cells are classified - cellular structure is less complex organisms whose organelles are not membrane bound.

all are prokaryotes and they divide by binary fission (the division of two identical cells)

characteristics of bacteria

size, shape, and arrangement

round shaped bacteria

paired bacteria

chain of bacteria

cluster of bacteria

a bacterial cell intermediate in morphology between a coccus and a bacillus - rod shaped, but also short and wide that they resemble cocci which is round

rod-shaped bacteria

spiral-shaped bacteria

bacteria that lose normal shape due to adverse environmental conditions; once normal conditions are reestablished cells revert to normal shape.

morphology, growth(varies with type of agar) motility, nutritional requirements, oxygen requirements (and carbon dioxide), pathogenicity, metabolism(secretion of waste products), proteins, genetics, staining, spore forming (sporulation)

flagella: long thin structures.. whipping motion

cilia: fine, short, hairlike extension located on the surface of the cell; rhythmic movement

obligate aerobes; require level of oxygen found in a typical room

microaerophiles; require oxygen but at a lower level than room air 5%

obligate anaerobes; will not grow if there is any amount of oxygen present in the environment

facultative anaerobes; able to survive in an environment that contains oxygen or no oxygen

aerotolerant anaerobes; grow best in environment without oxygen - can survive up to 15% oxygen

capnophiles; grow best in high concentrations of carbon dioxide

simple stain; used to determine basic shape and structures of cell; single dye such as methylene blue is used and the cell is rinsed with water.

Gram stain; cells are stained with crystal violet; washed with ethanol that removes purple stain from bacteria that don't retain the stain; red dye safranin is applied; specimen is rinsed with water.

*Gram positive bacteria retain the crystal violet and therefore are purple color.

*Gram negative bacteria do not retain the crystal violet an are red from the safranin stain.

**Gram-variable bacteria, Mycobacterium tuberculosis do not consistently stain red or purple

**Acid-fast stain; used to identify bacteria classified in the genus Mycobacterium. Red dye (carbolfuchsin) is retained by acid-fast bacteria

******Most common post-op bacterial infection (pathogen) - SSI

gram-positive coccus - common in the flora of the skin, hair and nares of nose

toxic shock syndrome

osteomyelitis

endocarditis

IV catheter infections, UTIs, prosthetic device infections, subacute bacterial infections, endocarditis

bacterial pneumonia

rheumatic fever, necrotizing fasciitis, strep throat, tonsillitis, scarlet fever

Neisseria gonorrhoeae - pelvic inflammatory disease deading to salpingitis

Moraxella catarrhalis - otitis media in children

clostridium is an example

*when conditions are unfavorable(extreme temps, dry, lack of food) the genetic material of the cell is enclosed in a protein capsule

*can survive for a long time until favorable conditions are reestablished, bacteria returns to vegetative state and able to grow

*not to be confused with reproduction, it is a method of bacterial survival

*are difficult to destroy; sterilization processes must be able to kill it

anthrax, meningitis, bacteremia, endocarditis, respiratory and cutaneous diptheria

Pontiac fever (influenza-like illness) Legionnaires' disease (severe form of pneumonia)

deep-tissue health care-associated infections in patients with burns, deep puncture wounds, and open bone fractures

chronic gastritis, stomach ulcers, peptic ulcers

Bacterial meningitis (primary cause in infants and children), respiratory tract infections, bacterial pneumonia (elderly), septic arthritis, cellulitis, eye infections

UTIs, sepsis, neonatal meningitis

Tuberculosis

Conjunctivitis, ocular lymphogranuloma venereum, lymphogranuloma venereum, nongonococcal urethritis, postgonococcal urethritis, infant pneumonia

transmitted through airborne droplet nuclei, usually infect the lungs but may also infect the kidneys, bone, joints, or skin.

annual testing

fit test for mask

require isolation precautions when surgical procedures are performed - PPE plus a NIOSH approved respirator

patient advised how he/she can prevent cross-contamination

nonliving particles that are completely reliant on the host cell for survival

*obligate intracellular parasites

*replication is directed by the nucleic acid within the host cell

*contain either DNA or RNA and a protein coat that encases the nucleic acid

*depend on the protein production of the host cell; does not contain the enzymes required for the production of energy

*no antibiotics are given

A protein covering that surrounds and protects the virus's DNA or RNA and aids in the attachment of the viral cell to the host cell

*composed of protein molecules called capsomeres

inhalation of respiratory droplets, exchange of body fluids, ingestion of food or water, bites by arthropod vectors

nucleocapsid

Hepatitis B (HBV) - blood, body fluids - liver cancer

Hepatitis C - blood-borne (silent killer - prior to 1980 no testing of blood) - liver cancer

Hepatitis D (Delta)

Human immunodeficiency Virus (HIV) - blood or other bodily fluids

Herpes simplex virus (HSV) - contact with fluid from lesions

Papillomavirus - direct contact with another person

Cytomegalovirus (CMV) - direct contact with body fluids

Cruetzfeldt-Jakob Disease (CJD) - exact mode of transmission unknown - prions (20hr) sterilization or properly dispose of instrumentation

"proteinaceous infectious particle"

do not contain DNA or RNA

changes normal PrP (a protein) from noninfectious spiral shape, alpha-helical, to the infectious folded shape called the beta-sheet

attack the brain (neurons) and cause diseases called subacute spongiform encephalopathies

**more common in animals, and include the two common forms of scrapie(disease that infects sheep and goats) and bovine spongiforms encephalopathy (commonly called mad cow disease)

in rare cases can be inherited as a mutant gene or sporadic case

20 year incubation time, mimics Alzheimer's disease, no vaccine or cure, definitive diagnosis is through histologic examination of affected brain and lymphoid tissue

WHO - recommends use of single-use, disposable instruments and the destruction of all reusable instruments

a new variant strain has a younger median age of onset at 28 years of age and longer duration of symptoms of 13 -14 months

more chemical indicators of prion accumulation in the neural and lymphoid tissues

Unicellular protozoans and Multicellular protozoans

the study of invertebrates that cause disease

metazoans category - endoparasites properly known as worms

most common worms are tapeworms, flukes, and roundworms

primary route of transmission = food or water contained eggs

also transfers by skin penetration, fecal-oral contamination, or arthropod bite

cause intestinal blockage and may rupture intestinal wall

human mobility, immigration from Third World countries

worms

unicellular eukaryotes

causes malaria and chronic sleeping sickness

the intestinal form of these are transmitted by fecal-oral route and are often responsible for infections in crowded environments such as day care centers and underdeveloped countries.

a protozoa that causes amebic dysentery

patients who are scheduled to undergo a sigmoidoscopy or colonoscopy

a unicellular anaerobic protozoan that is part of the normal flora of the vagina and urethra

If acidity of vagina is upset, protozoan population will grow causing trichomoniasis (usually a sexually transmitted disease)

Mycology

Fungi

called mycoses (mycosis=plural)

The majority of fungal diseases

zygomycosis

rhinocerebral zygomycosis

vaginal yeast infection

trench mouth (thrush)

immunocompromised patients should be monitored for infection

use disposable equipment

avoid use of power instruments

use neutral zone for passing sharps

sterile attire-gloves, face shields, knee-high impervious shoe covers

clean body fluid spills with sodium hydroxide (household bleach)

specimens into specimen container, then place biohazard bag labeled properly with this disease

per surgeon's order: clean patient's head with 1 molar sodium hydroxide at the end of procedure

place reusable instruments in impervious container, biohazard bacs, and labels with this disease according to hospital policy (policy may be disposal)

bodily fluids in biohazard bags labeled with this disease and kept separate from other red bags; notify environmental services to collect bags.

sharps in a separate container labeled with this disease; notify environmental services to collect and incinerate container

decontaminate all OR surfaces with 1 molar sodium hypochlorite for 60 min.. rinse with water then give routine cleaning

visible bioburden decontaminated with 1:10 dilution of 5.25% sodium hypochlorite...followed by routine cleaning with disinfectant

Frequent handwashing helps to eliminate these primary agents

Direct contact - Indirect contact - Droplet particle size(>5um) - Airborne spread particle size (<5 um)

divided into two groups:

environmental: (1) personnel, (2)the environment, and (3)contaminated instrumentation

endogenous: patient's endogenous flora

personnel hair, skin, and nares are reservoirs of bacteria, which may be discharged in particle form into the air and therefore pose a risk of these to the patient.

gowns and drapes cover the skin on areas of the body other than the hands. The primary purpose of wearing PPE around the OR table is to provide a barrier to contamination, both from personnel to patient and from patient to personnel. This is termed surgical conscience

A second source of microbial transmission is through the air and through these inanimate objects that may contain infectious microorganisms including walls, floors, cabinets, furniture and equipment

contaminated antiseptic solutions, contaminated wound dressings, and contaminated or improperly sterilized surgical instruments

two primary sources of SSI risk to the patient:

1. encountered in contaminated procedures

2. resident (the normal) flora of the skin

shown to reduce SSIs

carriers of S. aureus are at particular risk for SSI

age: pediatric or geriatric lower immunological defenses

obesity: diminished blood flow

general health: poor health=predisposed to infection

carriers of S. aureus or MRSA: greater risk from their own flora

remote infections: other body site infections; will travel

preoperative hospitalization: duration of operative stay

preexisting illness and related treatment: rates are higher in patients with compromised immune systems from preexisting illness, patients on meds., etc.

notify all units

remove all unnecessary equipment and supplies from the OR as possible and everything else as far from the OR table as possible

cover all OR surfaces; electrical cords with sterile plastic sleeves

malnutrition, tobacco use, diabetes, malignancy, immunosuppression, high staph carriers, ruptured appendix (fecal matter in the colon)

Preoperative hair removal: use of razors carries a greater risk than the use of clippers. Blades leave many small cuts on the skin, allowing bacteria easier access for colonization. Depilatory cream is a safer alternative

Type of procedure: clean-contaminated (class II), contaminated (class III), and dirty (class IV), cases carry a higher risk of infection

Duration of procedure: longer anesthetic and operative times have an accompanying increase in time for bacterial contamination to occur, increased tissue damage, and greater immunosuppression, fatigued team members which may break sterile technique

use of eye protection, laundering of scrub attire, wearing jewelry, wearing the lab coat/cover gown, hand hygiene and fingernails, head covers, shoe covers (during operation)