infection control

Infection

Results when pathogen invades tissue and begins growing within host

Pathogen or microorganisms

Agent that can cause disease in a host organism

Colonization

Presence and growth of microorganisms within a host but without tissue invasion or damage

Communicable disease

An infectious disease that can be transmitted directly from one person to another

Symptomatic

Showing symptoms

Asymptomatic

Showing no symptoms

The chain of infection

How infection is spread; the chain must remain uninterrupted to cause infection

Infectious microorganisms

Living organisms too small to be seen with naked eye (virus, fungus, bacterium, protozoan)

Potential to cause disease depends on

Sufficient numbers of organisms, virulence (pathogenic), ability to enter and survive host, susceptibility of host

Resistant organisms/ multi drug resistant organisms (MDROs)

Overuse or misuse of antibiotics, examples: methicillin-resistant staphylococcus aureus(MRSA), Vancomycin resistant enterococci (VRE), clostridium difficile (c.diff)

Blood borne pathogens

Spread via contaminated blood and body fluids. Examples: hepatitis b and c, hiv

Breaking the infectious micro chain

Clean contaminated objects. Clean disinfectant and sterilize

Clean

Just soap and water to clean contaminated

Disinfectant

Doesn’t get rid of spores but does get rid of micros

Sterilize

Gets rid of spores and micros

Reservoir

Is a place where a pathogen can survive and multiply (conducive environment)

Environments reservoirs provide for organisms to thrive:

Food, oxygen, water, temperature, pH, light. They like dark warm moist places and neutral or alkaline pH

Common reservoir

Human body (hands)

Breaking reservoir chain

Hand hygiene, bathe pt with soap and water or chlorhexidine, change soiled dressings and dispose properly (fluid resistant bag), dispose of needles including puncture proof containers, keep surfaces clean and dry (bedside/over bed table), keep solutions tightly capped, keep wound drainage tubes and collection bags patent, do not raise collection bags above site being drained, empty and dispose of suction bottles per facility policy

Portal or exit from reservoir

Skin and mucous membranes, respiratory tract, urinay tract, gastrointestinal tract, reproductive tract, and blood

Breaking reservoir chain- respiratory

Cover mouth and nose when coughing and sneezing, mask if suffering from URI

Breaking reservoir chain- urine feces and blood

Wear gloves when handling blood and body fluids, wear gown and eyewear if chance of splashing, handle all lab specimens as if infectious biohazard bag

Contact transmission

Direct- person to person

Indirect- object to person

Droplet transmission

From respiratory tract (sneezing)

Airborne transmission

Small and in the air (breathe in)

Vehicles transmission

Bed pans, food, solution, blood specimens

Vector transmission

Insects: internal (flies land on stuff) external( ticks and mosquitoes bite you)

Breaking transmission chain

Hand hygiene, avoid shaking bed linen or clothes, avoid contact of soiled items with uniform, discard any item that touches the floor, utilize fluid resistant bags (red is biohazard, blue is linen, white and brown is trash/linen, yellow is chemotherapy)

Breaking transmission chain- skin and mucosa

Maintain integrity (lubricants frequent hygiene and turn), clean wounds thoroughly and keep covered prn, dispose of needles in puncture proof containers

Breaking transmission chain- urinary

Sterile technique during insertion of catheters, keep drainage system closed and intact, maintain downward flow of urinary system

Susceptible hosts

Depends on individual’s degree of resistance to a pathogen. Influenced by status of natural defenses and presence of risk factors. Immunocompromised

Breaking susceptible host chain

Bathe regularly, perform oral hygiene, provide adequate nutrition and fluids, provide immunizations, ensure adequate rest, encourage regular exercise, and reduce stress

Normal defenses against infection

Normal flora, body system defenses, inflammatory responses

Normal flora

Micros that reside on body or within the body. (Skin, saliva, oral mucosa, GI and GU tracts). Serve to protect the body from pathogens. Do not cause infection while residing in usual area.

skin (bod system defense)

First line of defense and is a barrier skin cells shed (micro come off), oily secretions

Mouth (bod system defense)

Intact barrier. Saliva (spit has micro)

Eyes (bod system defense)

Protective barriers (blinking, tearing). Dry eyes/ puncture in eyes/ splashing in eyes

Respiratory (bod system defense)

Lungs are lined with cilia (trap micro).

Urinary tract (bod system defense)

Flushing of urine. Bladder has intact epithelium. UTI, urinary retention

Gastrointestinal tract (bod system defense)

Gastric acid. Ph is low. Rapid peristalsis is a protective barrier

Vagina (bod system defense)

Flora helps keep ph level acidic. Antibiotics can cause yeast infections

Inflammatory response

Cellular response to injury or irritation that protects the body from infection

Three stages of inflammatory response

Vascular and cellular responses, inflammatory exudate (secretions): serous (clear, plasma like), sanguineous (contains red blood cells-pink tinged), purulent (contains wbc’s and bacteria-pus), and tissue repair

first stage: incubation period

Micro invaded susceptible host. Pt is asymptomatic

Second stage: prodromal stage

Start seeing signs/symptoms. Fatigue, low grade fever. Micro is surviving and multiplying

Third stage: illness stage

Specific signs/symptoms to disease process

Localized infection

Pain/tenderness, purulent drainage, swelling (edema), redness, warmth or heat at involved site. Can see and feel these

Systemic infection (septic)

Fever, fatigue/malaise, nausea/vomiting, swollen lymph nodes, increased hr and rr, decreased bp, decreased activity or level of consciousness (LOC). Body symptoms. Elevated WBC (normal is 5000-10000/mm³. Positive cultures-wound,sputum,urine,blood

Fourth stage: convalescence

Symptoms disappear. Still tired and low energy

Pts at risk

The young, the old, nutritional status, stress, disease processes, pts in healthcare setting: (Health care-Associated infections) result from delivery of healthcare, occur as result of invasive procedures antibiotic administration presence of multidrug resistant organisms and breaks in infection prevention and control activities. Common sites: surgical/traumatic wounds, urinary and respiratory tracts, bloodstream

Treatments for infection

Identify causative organism: culture, administer prescribed antibiotics, support/improve pt defenses, educate pt, prevent spread (med and surgical asepsis, standard and isolation precautions

Asepsis

Absence of pathogenic micros

Aseptic technique

Refers to the practices/procedures that help reduce the risk of infection

Two types of asepsis

Medical and surgical

Medical asepsis (clean technique)

Goal is to reduce or prevent the spread of micros (transmission). Hand washing, antiseptic hand wash, antiseptic hand rub, surgical hand scrubs. Barrier techniques: standard and isolation precautions. Includes proper cleaning and disinfection of inanimate objects. Commonly used in home environment

Surgical asepsis (sterile technique)

Goal is to eliminate ALL micros from an object or area. Used in special circumstances: during procedures that require intentional perforation of pts skin, when skin integrity is broken due to trauma surgical incision or burns, during procedures that involve insertion of catheters or surgical instruments into a sterile body cavity (urinary catheters)

Standard precautions

Protects the nurse patient family and friends, used with every pt in all healthcare settings, controls the modes of transmission of infections, applies to blood all body fluids secretions excretions (except sweat) non-intact skin and mucous membranes

Hand hygiene standard precautions

HH before during and after direct pt contact, after contact with blood body fluids secretions excretions and after contact with contaminated items, after removing gloves, hands are soiled or contaminated, when caring for pt with spore forming organisms (c diff or norovirus), alcohol based hand rubs in right circumstances

PPE standard precautions (barriers)

Protect health care provider from infectious material. Gloves, gowns, masks, goggles

Safe injections/management of sharps standard precautions

Use sterile single use disposable needles, single dose vials, do not recap dirty needles, use safety devices, and dispose of all sharps in puncture proof containers

Respiratory hygiene/cough etiquette standard precautions

Cover nose/mouth with tissue during cough or sneezing and dispose of, hh after contact with respiratory secretions and contaminated objects, place surgical masks on pt if it does not compromise respiratory function, spatial separation greater than 3 ft from persons with respiratory infection and coughing

Isolation and isolation precautions

Separation and restriction of movement of persons with contagious diseases- infected or colonized, pts are often placed in standard hospital rooms, isolation carts placed outside pts room, dedicated care equipment- BP cuff (sphygmomanometer) thermometer stethoscope pen, psychological implications- they will feel isolated physically and socially. Isolation precautions include standard precautions, but standard do not include isolation precautions

Airborne precautions transmission based

Used for droplet nuclei smaller than 5 microns (stay in air longer)

Infection condition: measles, chicken pox (varicella), disseminated varicella zoster (shingles), pulmonary laryngeal (mycobacterium) tuberculosis (tb), Covid if on aerosol procedures

Barrier protection: private room, negative pressure air flow of at least 6-12 exchanges per hour, mask or N95

Droplet precautions transmission based

Used when droplets are larger than 5 microns being within 3 ft of pt.

Infection condition: diphtheria (pharyngeal), rubella, streptococcal (group A) pharyngitis, pneumonia or scarlet fever in infants, pertussis, mumps, mycoplasma pneumonia, meningococcal pneumonia or sepsis, pneumonic plague, influenza, Covid

Barrier protections: private room, surgical mask or respirator

Contact precautions transmission based

Required when there is direct and indirect pt environmental contact.

Infection condition: colonization or infection with multidrug resistant organisms such as VRE and MRSA, clostridium difficile, shigella and other enteric pathogens (norovirus, ESBL), major wound infections, herpes simplex, scabies, disseminated varicella zoster, RSV.

Barrier protection: private room, gown, gloves, pt can leave room if infectious material is contained or covered

Protective environment transmission precautions

When protecting pt from infection. Condition; allogenic hematopoietic stem cell transplant, post organ transplant, immunocompromised pt

Barrier protection: private room, positive pressure room, hepa filtration, mask, gloves, gown, no fresh flowers

Donning ppe

Wash hands, apply gown, apply mask, apply eyewear, apply clean gloves

Doffing ppe

Remove gloves, remove eyewear, remove gown, mask, wash hands