Unit 3- infection control- exam 6/11

Microorganisms

• grow in/ on host organism & cause disease (Infections)

Varicella (chicken pox) is what 2 isolation precautions?

1. Airborne

2. Contact

Infection

• establishment & growth of a microorganism on/in a host

Pathogens & 3 main points

• disease producing microorganisms

1. Multiply in large #s & cause an obstruction

2. Cause tissue damage

3. Can secrete organic substances called exotoxins

Main pathogens we see

1. Fungus

2. Virus

3. Protozoa

4. Bacteria

Exotoxins

• produce high body temps, nausea, vomiting, or shock

Bacteria

• microscopic, single-celled organisms

  • May reside in host in a group or a cluster (colony)

Classification of bacteria through morphology (size or shape):

1. Cocci/ spheres

2. Bacilli/ rods

3. Spirals

Common bacteria infections encountered today

1. streptococcal pharyngitis (strep)

2. Bacterial pneumonia

3. food poisoning

Virus

• cannot live outside a living cell

• Depends on host cell to provide missing factors

How a virus comes to be:

• viral particle (virion) attaches to host & inserts its genome/genetic information into the host

  • Can lay dormant/latent at times

Fungi/fungus

• size much larger than bacteria

• Some are medically important

Dimorphic

Medically important fungi (yeast or mold)

Common fungal infections:

• athlete’s foot

• Ringworm

• Tinea nigra

Protozoa

• larger than bacteria

• Classified by their motility

• Live on or in other organisms at expense of host

• Can ingest food particles, some are equipped with digestive systems

Common parasitic infections:

• pinworms

• Tapeworms

• Malaria

Chain of infection 4 factors

1. Host

2. Infectious microorganism

3. Mode of transportation

4. Reservoir

• if at any point the chain is broken, the cycle does NOT continue

6 cycle chain of infection

1. Susceptible host

2. Pathogen

3. Reservoir

4. Portal of exit

5. Mode of transmission

6. Portal of entry

Susceptible host

• elderly

• Infants

• Immunocompromised

• ANYONE

  • Humans provide favorable host environment due to nutrients & metabolites

Microorganisms tend to like:

• warm temperatures

• Moisture

• Darkness

Mode of transmission

• how the pathogen transported outside the body & into the next

Exogenously transmission

From outside the body

• encounter w/ a microbe in the environment

• Direct/indirect

Endogenously transmission

From inside the body

• encounter W/ organisms already inside/ on body; when normal flora of the body is transported to a different area

Direct host-to-host

• infected individual transmits an infection by any number of methods such as:

  • Handholding

  • Coughin

  • Sexual contact

  • Phlegm

  • Aerosols (sneezing/coughing)

Indirectness host-to-host

Direct w/ assistance via a vector or fomite

Vector

Usually an arthropod

• takes blood from 1 host & carries it to the other

  • Ex:

    • Tick/ insects

Fomite

Inanimate object that has been in contact with/ an infectious organism

• Ex:

  • Food, water, radiographic equipment

T/F:

Staphylococci on surface of skin can go deeper within a laceration

True

Reservoir

Site where an infectious organism can remain alive & from which transmission can occur

Reservoir types & examples:

People, animals, inanimate objects

People= infected person who doesn’t know they have the disease

Animals= cow (Ingested milk)

Insects= ingests blood containing pathogens

Inanimate objects= dusty corner, contaminated linen, food

Types of infections:

1. Healthcare associated infection

2. Communicable

3. HIV

4. Hepatitis

5. MDRO

   • MRSA, VRE, C-diff

6. Tuberculosis

Healthcare associated infections (HAI):

• infections acquired while receiving treatment in healthcare setting for another condition

Healthcare associated infections examples:

1. UTI (most common)

2. Surgical site

3. Bloodstream

4. Pneumonia

Nosocomial Infection

• specific to receiving infection at a hospital

• 5% of all hospital patients acquire additional condition while in hospital

Iatrogenic

• infection that is a result of intervention w/ a physician

Sources of hospital acquired infections:

• medical personnel

• Patient flora

• Contaminated healthcare environment

• Blood-borne pathogens

• Invasive procedures

Communicable diseases

• disease spread from 1 person to another through:

  • Direct contact with blood/bodily fluids

  • Inhaling airborne virus

  • Insect bite

HIV

• Blood-borne pathogen

• virus that attacks the body’s immune system

  • Without treatment leads to AIDS

• No cure (just control)

• Transmitted by infected bodily fluids like blood, sharing needles, semen, vaginal fluids, & breast milk

HIV vs AIDS

Human immunodeficiency virus

Acquired immunodeficiency syndrome

HIV leads to aids if untreated

Hepatitis B/ HBV

• blood-borne pathogen

• Causes illness that primarily affects the liver

• Results in:

  • Swelling, soreness, loss of normal function of liver

How is hep b transmitted?

• contaminated needle (BIGGEST FOR HEALTHCARE WORKERS)

• Penetrating injury

• Intimate contact

Hepatitis B vaccination

• series of 3 injections

• After receiving the hepatitis B vaccine & a positive antibody tiger is obtained, there is no risk of hepatitis B disease

MDRO

• multi-drug resistant organism

• Bacteria & other microorganisms that have developed resistance to antibodies

Common examples of MDRO

1. MRSA

2. VRE

3. C-diff

4. ESBLs

5. PRSP

6. Multi-drug resistant Tuberculosis (MDR)

MRSA

• Methicillin-resistant staphylococcus aureus

  • Easily colonized on skin

  • Ex:

    • Decubitus ulcers, pneumonia, endocarditis, bacteria, osteomyelitis, septic thrombophlebitis

Most susceptible patients to MRSA:

• nursing home

• Dialysis

• Aged

• ICU

• Hospitalized for long periods of time

VRE

• vancomycin- resistant enterococcus

  • Infections caused by enterococci

    • Typically in hospital patients (UTI, surgical wounds, blood streams)

  • Resistant to vancomycin

C. Diff

Clostridium difficile

• spore forming bacterium that releases toxins into the bowel

  • Resistant to disinfectants

**must wash hands shawty

Tuberculosis (TB)

Drug resistant airborne bacilli

• recurrent, chronic disease affecting the lungs caused by the spore-forming mycobacterium tuberculosis

  • Spread by droplet (cough, sneezes, airborne)

  • Treatable disease w/ antibiotics

  • Primary, latent, & active disease

How do I prevent disease transmission?

• wash hands

• Get immunizations

• Get boosters

• Follow post-procedure protocols

• Break chain of infection

CDC

Center for disease control & prevention

• mission is centered on preventing & controlling disease & promoting environmental health & health education in the U.S.

CDC roles:

• detected & respond to new health threats

• Standard precautions

• Promoting health & safety

Standard precautions

• used when performing procedures that may require contact w/ blood, body fluids, secretions, excretions, mucous membranes, & non-intact skin

  • All patients should be regarded as potentially infectious

Practice bio safety techniques:

1. Handwashing

2. Gloving

3. PPE

4. Needle recapping

5. Biospills

What is the most effective method used to prevent the spread of infection?

Handwashing (20 seconds; before & after patient)

Protect the following against acquiring pathogens that are known or unknown:

1. Healthcare workers

2. Patients

3. Anyone in direct contact

4. Anyone in indirect contact

Gloves

• remove inside out due to contamination

Sequence for donning PPE

1. Gown

2. Mask/respirator

3. Googles/face shield

4. Gloves

Sequence for doffing PPE

1. Gloves

2. Goggles/face shield

3. Gown

4. Mask

Need recapping

• 800,000 needle stick injuries & other injuries from sharp objects annually

Biohazard spills

• Red biohazard bag

Airborne

• pathogenic organisms that remain suspended in the air for long periods on aerosolize droplets or dust

  • Negative pressure room

  • Required to wear N95

Airborne examples

• TB

• Chickenpox (varicella)

  Measles (rubeola)

Droplet

• infected w/ pathogenic organisms

  • Infect another through mouth, nasal mucosa, conjunctiva

Droplet examples

• rubella

• Mumps

• Flu

• Adenovirus

  • Must wear surgical mask within 3 ft

Contact

• a patient is infected w/ a virulent pathogen that spreads by direct contact w/ the patient or by indirect contact w/ a contaminated object (dressing, bed rail)

Contact examples

• MRSA, hepatitis, staph, varicella

Environmental

• c-diff

• Norovirus

  • Must wash hands with soap & water

  • Clean w/ bleach

Reverse isolation

• compromised/immunosuppressed patients

  • AKA neutropenic

Reverse isolation/ neutropenic examples

• aplastic anemia

• Leukemia

• Lymphoma

• AIDS

• Severe burns

Aseptic

• freedom from infection/ absence of infection

Medical Asepsis

• reduction in numbers of infectious agents, decreasing probability of infection

  • Not necessarily a reduction to zero

Surgical asepsis

• used to prevent contamination of microbes before, during, & after surgery using sterile technique

  • Complete removal of microorganisms & spores

Disinfection

• as many microorganisms as possible are removed from surfaces by chemical or physical means

Sterilization

• complete destruction or elimination of all living microorganisms by dry heat, moist heat, gas or chemicals

  • ABSOLUTE KILLING OF ALL LIFE FORMS

4 types of physical sterilization

1. Heat

2. Gas

3. Chemicals

4. radiation/ UV

Moist heat

• autoclave

  • Steam pressure, rapid sterilization

Dry heat

• requires higher temperature for longer time

  • oven is used

• Non- aqueous materials

Gas

• Ethylene oxide

• used for electronic & plastic equipment that could be damaged by heat

  • Effective, but toxic to humans

Chemicals

• used for objects that are high heat sensitive

Radiation/UV

• 260 nm; germicidal lamps

What radiology procedures require sterile technique

• angiography

• Arthrograms

• Hysterosalpingograms

• X-ray in O.R.

• Myelograms

Sterile field

• microorganism-free area that can receive sterile supplies

• DO NOT reach across a sterile field

• A 1-inch border around the sterile field is NOT considered sterile

Sterile trays

• Myelogram (spinal tap) tray

• Arthrogram tray

  • May be packed commercially or by hospital

Sterile vs nonsterile tape

Sterile= black lines

Nonsterile= white lines

3 purposes of surgical scrubbing

1. Removes debris & transient microorganisms (hands to forearms, including nails)

2. Reduces resident microbial count

3. Inhibits rapid rebound growth of microorganisms

2 methods of surgical scrubbing

1. Numbered stroke method

2. Timed scrub (minimum of 3 minutes per hand/arm)

What is sterile during a sterile procedure?

• patient

• Table & other furniture covered w/ sterile drapes

• Personnel wearing sterile attire

Skin prep

• antiseptic soap applied from the center out, using firm circular motion

What is the most common site for hospital acquired infections? (HAI)

Urinary catheters

Urinary catheters definition

• insertion of a tube into the bladder using aseptic technique

Foley catheter

Has a balloon which is filled with/ sterile water to hold the catheter in place

• Indwelling catheter remains in place

Straight catheter

• no balloon

  • Used for quick drainage/ short term

Urinary catheters size

• 8-20 in even #s based on French system

  • Choose larger size when possible

  • System equals the outer diameter of the catheter

Suprapubic catheter

• closed drainage system inserted approximately 1” above pubic symphysis into distended bladder

  • Reason:

  • Long term

  • Urethral injury

  • Obstruction

Condom catheter

• specially designed condom w/ a catheter at the end attached to a collecting bag

Procedures that need sterile technique

• tacheostomies

• Chest tubes

• Central venous & arterial lines

• Pacemakers

Non-aseptic techniques examples

• male urinals

• Bed pans

• Enemas

Bedpans

• offered to patients who are not ambulatory

• Used for urine & fecal collection

Two types of bedpans

Standard:

• made of metal/plastic

• 2 inches high

Fracture bedpan

• shallower (1/2” high)

• Contoured for patient comfort

**if pt is able to sit up, elevate bed to 60 degrees