copyright © 2007 by saunders, inc., an imprint of elsevier inc. infection control chapter 26

Copyright © 2007 by Saunders, Inc., an imprint of Elsevier Inc.

Infection Control

Chapter 26

Copyright © 2007 by Saunders, Inc., an imprint of Elsevier Inc. Slide 2

Disease

An alteration in the normal structure or function of an organism or a cell.

Causes specific clinical signs, symptoms, and laboratory findings that set it apart.

A disease could be either inherited, drug-induced, autoimmune, degenerative, or infectious.

Any disease caused by the growth of pathogenic microorganisms in the body is considered an infectious disease.


Conditions Required for Microbial Growth

To maintain a healthcare environment that is as free as possible of pathogenic organisms, the MA must prevent or eliminate as many growth requirements as possible.– Nutrients

– Moisture

– Temperature

– Darkness—organisms grow best in dark environments

– Oxygen—aerobes or anaerobes

– Neutral pH


Chain of Infection

Infectious diseases can spread only if certain factors occur. These factors, or links, make up the chain of infection. Break the chain, and you break the infectious process.

The chain begins with the infectious agent, which invades the reservoir host, and continues with the means or portal of exit from the host, the method of transmission, the means or portal of entry into a new host, and the presence of a susceptible host.


Chain of Infection


Pathogenic microorganisms include (see Tables 26-1 through 26-4):

– Viruses—smallest; obligate intracellular parasites; palliative treatment

– Bacteria—classified by their morphology; some produce spores; normal flora vs pathogenic microbes

– Protozoa—unicellular parasites; frequently transmitted by vectors

– Fungi—molds and yeasts; mycotic infections and tineas

– Rickettsiae—similar to both viruses and bacteria; carried by vectors; e.g., Lyme disease

Infectious Agents


Antibiotic Resistance

Antibiotic resistance is one of the world’s most significant public health problems.

Infectious microorganisms whose presence was once easily treated with antibiotics are growing increasingly resistant to the drugs.

Resistance occurs when an antibiotic is used inappropriately to treat an infection.

The pathologic organism mutates, decreasing the effectiveness of the drug.


CDC Recommendations

Prescribe antibiotic therapy only when it will benefit the patient.

Bacterial infections can be treated with antibiotics, but viral infections, because they involve viral takeover of cellular DNA or RNA material, cannot.

Treat the patient with an antibiotic that is specific to the bacterial infection.

Prescribe the label-recommended dose and time interval for the medication.


Reservoir Hosts

May be people, insects, animals, water, food,

examination rooms, contaminated instruments,

and so on

Supply nutrition for the organism, allowing it to

multiply

Either cause infection in the host and/or exit from

the host to cause disease in another host


Portal of Exit

How the pathogen escapes the reservoir host

Includes mouth, nose, eyes, intestines, urine, reproductive tract, and so on

Standard precautions prevent spread


Transmission

Direct—contact with infected person or with discharges (feces, urine, sputum, etc.)

Indirect—from droplets expelled with coughing, sneezing, or speaking; vectors; contaminated food; contaminated objects called fomites.

Controlled with sanitization, disinfection, sterilization, and so on


Portal of Entry

How the pathogen gains entry to a new host

Similar to means of exit (e.g., mouth, eyes, nose)

Intact integumentary system is first line of defense

Inflammatory response and immune system are second lines of defense

– Humoral immunity—produces antibodies specific to antigen exposure

– Cell-mediated immunity—destroys pathogens at the site; e.g., phagocytosis


Susceptible Host

Must be capable of supporting the pathogen

Susceptibility depends on:

– Location of entry

– Dose of pathogen

– Health state of new host

– Immunization status


Body’s Natural Protection

Intact skin. Mucous membranes protect underlying tissues

and trap foreign substances. Cilia trap invading microbes. Sneezing and coughing expel organisms. Body secretions, such as tears and sweat, expel

foreign substances from the body. pH of many of the body’s organs discourages

microbial growth.


The Inflammatory Response

The inflammatory response is the body’s protective reaction to a foreign substance or antigen.

To defend itself, the body initiates specific responses that destroy and remove pathogenic organisms.

The release of inflammation mediators, through three separate actions, results in an increase in white blood cells (WBCs) at the site.

WBCs attack the pathogen and attempt to contain the infection at its original site.


Inflammatory Response


Four Classic Signs and Symptoms of Inflammation

Redness or erythema

Swelling or edema

Pain

Heat


Site of Injury

Blood vessels dilate, causing an increase in the local blood flow, resulting in redness and heat.

Blood vessel walls become more permeable, which helps in releasing WBCs to the site.

– Blood plasma filters out of the more permeable vessel walls, resulting in edema, causing pressure on nerves and pain.

Finally, chemotaxis, the release of chemical agents, attracts WBCs.


WBC Protection

WBCs form a fibrous capsule around the injury, protecting surrounding cells from damage or the source of infection.

Destroyed pathogens, cells, and WBCs collect and form a thick, white substance called pus.

WBCs engage in phagocytosis, or the engulfing and destruction of microorganisms and damaged cells.


Inflammatory and Infection Terms

Lymphadenopathy

Septicemia

Pyemia

Prodromal period

Chronic vs acute infection

Latent infection—relapse and remission (e.g., oral herpes simplex)


Infectious Bodily Secretions

OSHA has designated the following bodily fluids as potentially infectious with blood-borne pathogens:

– Cerebrospinal fluid (CSF); synovial, pleural, pericardial, peritoneal, mucous, and amniotic fluids

– Blood, vaginal and seminal secretions, saliva, and human tissue


OSHA Standards for Healthcare Workers

Healthcare workers face significant health risks from occupational exposure to blood or other potentially infectious materials that may contain hepatitis B virus (HBV), hepatitis C virus (HCV), or the human immunodeficiency virus (HIV).

The MA should use precautions for all patients, regardless of knowledge of their individual health histories.

Implementation of the Bloodborne Pathogen Standard also protects patients from any blood-borne infection the healthcare worker may be carrying.


Exposure Control Plan

Plan must detail employee protection procedures.

Must identify job classifications and/or specific work-related tasks that might lead to exposure.

Must contain specifics on controls including PPE, training, hepatitis B immunization, record keeping, postexposure follow-up, and labeling and disposal of biohazard waste.

Must be reviewed and updated at least annually to incorporate the use of safer medical devices.

Must be available to employees for review and training.


Bloodborne Pathogen Standard

Employers must keep a confidential sharps injury log that describes the device involved and the details of how and where the incident occurred.

Must have available sharps management devices, such as self-sheathing or retracting needles, and needleless intravenous (IV) systems.

Should wash exposed area immediately or as soon as possible after exposure.


Hand Hygiene Guidelines Visibly soiled hands should be washed for minimum of

15 seconds with antimicrobial soap and warm running water.

Alcohol-based handrubs, if used correctly, significantly decrease number of microorganisms, take less time to use, and cause less irritation than traditional hand washing.

Hand washing or alcohol handrubs should be used before and after each patient is seen as well as after gloves are removed.

Apply label-recommended amount of handrub to palm of one hand and rub hands together, covering all surfaces until hands are dry.


Handrubs and Antimicrobial Soap


Hand Hygiene

Studies show that even after careful hand hygiene, healthcare workers with artificial nails have more pathogenic microbes than workers with natural nails.

Natural nail tips should be no longer than ¼ inch.

Contact dermatitis from alcohol handrubs is uncommon.


Compliance Guidelines

Safety and infection control fundamentals go beyond hand washing and knowledge of the disease cycle.

Five basic parts to compliance:– Barrier protection

– Environmental protection

– Housekeeping controls

– Hepatitis B vaccination

– Postexposure follow-up


Barrier Protection

Protective equipment must be used if you will be involved in any of these activities:

– Touching a patient's blood and body fluids, mucous membranes, or broken skin

– Handling items and surfaces contaminated with blood and body fluids

– Performing venipuncture, finger punctures, injections, and other vascular-access procedures


Barrier Protection

– Assisting with any surgical procedure. If a glove is torn or an injury occurs, the glove is removed and replaced with a new glove. The instrument is removed from the sterile field.

– Handling, processing, and disposing of all specimens of blood and body fluids.

– Cleaning and decontaminating spills of blood or other body fluids.


Personal Protective Equipment (PPE)

Specialized clothing or equipment that prevents blood or other potentially infectious material from passing through to reach the healthcare worker

Includes latex gloves, face masks, face shields, protective glasses, laboratory coats, barrier gowns, mouthpieces, and resuscitation bags that protect the healthcare worker from potentially infectious substances


Personal Protective Equipment (PPE)


PPE Guidelines

Protective equipment contaminated with body fluids of any kind must be removed and placed in a designated area or biohazard container.

Protective eyewear and/or face shields must be worn whenever splashes, sprays, or droplets may occur.

Utility gloves may be reused if they are intact without cracks, tears, or punctures.

All PPE must be removed before the worker leaves the medical facility.


Environment Protection

Observe warning labels on biohazard containers and equipment.

Minimize splashing, spraying, and spattering of drops.

Bandage any breaks on hands before gloving.

Do not recap, bend, break, or resheath contaminated sharps.

Immediately after use dispose of sharp items in a labeled, leakproof, puncture-resistant biohazard container.


Environment Protection

All specimens must be placed in a container that prevents leakage

Contaminated equipment should be sanitized before being repaired in the office or transported to the manufacturer.

Smoking, eating, drinking, applying cosmetics or lip balm, and handling contact lenses are prohibited in work areas where there is reasonable likelihood of contamination from blood-borne pathogens.

Food and drink cannot be kept in the same areas as potentially infectious materials.


Housekeeping Controls

Post schedule for cleaning and specific information about each work area where exposure could occur.

Immediately decontaminate areas after accidental spills and at the end of each procedure.

Disinfect reusable containers on routine basis.

Sharps containers must be upright and as close as possible to the work usage area; not overfilled; replaced on a routine basis with lid closed securely.



Use appropriate equipment to pick up spilled material or broken glassware.

Place in impervious biohazard bag or container.

Use an absorbent professional biohazard spill preparation as directed to decontaminate the site.

Wear gloves to handle soiled linen; should be double- bagged and transported in labeled, leakproof biohazard bags.

Biohazard waste must be collected in impermeable red biohazard-labeled bags or containers and sealed.


Hepatitis B Vaccination

Must be available free of charge within 10 days of starting employment to all employees who are at risk.

Intramuscular injection in three doses; second injection 4 weeks after first, and third injection 6 months after first.

U.S. Public Health Service does not currently recommend routine boosters.

Should have blood titer drawn after completion to determine if antibodies are present.

Employees have right to decline immunization but must sign a declination form.


Hepatitis B Vaccination


Postexposure Follow-up

Postexposure follow-up involves immediate cleansing of the site, completion of an exposure incident form, confidential medical evaluation, examination of the source individual and worker’s blood, health counseling, and confidential treatment of all medical records.


Aseptic Techniques: Prevention of Disease Transmission

Medical asepsis.

Surgical asepsis.

Medical aseptic techniques: Create an environment as free of pathogens as possible to prevent reinfection or cross-infection.

Surgical aseptic or sterile technique: Used when the patient’s skin or mucous membranes are disrupted. Prevents patient exposure to all microbes (e.g., for minor surgery, urinary catheterizations, injections).


Hand Washing

Reduce skin bacteria with mechanical friction, antimicrobial soap, and warm running water.

Goal is to remove or decrease the numbers of transient bacteria on the surface of the skin, thus preventing transient bacteria from becoming resident bacteria.

Proper hand washing depends on two factors: running water and friction.

All jewelry except a plain wedding band should be removed.

Lotion may be used to prevent cracked or chapped skin.


Hand Washing

Wash hands under running water with fingertips pointing down.

Apply antimicrobial soap and use friction to hands and wrists.

Run water from the wrists down toward the fingertips.

Alcohol handrubs may substitute for hand washing unless hands are visibly contaminated.

Handrubs can be more effective in reducing nosocomial infections than hand washing.


Hand Washing


Sanitization

Cleaning of contaminated articles or surfaces to reduce the numbers of microorganisms to a safe level as dictated in public health guidelines

Removes debris such as blood and other body fluids from instruments or equipment

Must wear utility gloves to prevent possible personal contamination

Completed immediately after use in a separate workroom or area to avoid cross-contamination


Sanitization

Separate sharp instruments from others to prevent injury and protect instruments.

Open hinges and scrub serrations and ratchets.

Rinse instruments in hot water and check proper working order.

Items should be hand dried.

Ultrasonic sanitizers are helpful because they do not damage instruments and workers are protected from an accidental sharps injury.


Sanitization


Disinfection

Process of killing pathogenic organisms or making them inactive.

Not always effective against spores and viruses.

1:10 bleach solution is an effective disinfectant for surfaces contaminated with viruses, including HIV.

Important to follow manufacturer’s guidelines on how to properly use each disinfectant.


Disinfection


Disinfectant Errors

Instruments not thoroughly sanitized, and organic matter inhibits or prevents action.

Moisture on instruments dilutes disinfectant solution beyond effective concentration.

Solution left in an open container.

Solutions not changed as recommended and expire.

Not prepared properly.

Recommended manufacturer’s temperature for use and storage is not maintained.


Sterilization

Destruction of all microorganisms.

Requires space for a sink as well as receiving basins, proper cleaning agents, brushes, autoclave wrapping paper, sterilizer envelopes and tape, sterilizer indicators, disposable gloves, and designated biohazard waste containers.

Another section should needed for storage of sterile items.


Role of the Medical Assistant

It is important that aseptic techniques and infection control be done on such a routine basis that they become an unbreakable habit.

MA should teach patients about infection control and the potential danger of blood and body fluids, including demonstrating aseptic techniques, the management of infectious materials at home, and the importance of frequent and consistent hand washing.

copyright © 2007 by saunders, inc., an imprint of elsevier inc. infection control chapter 26

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