La Consolacion University Philippines

(formerly University of Regina Carmeli)

Graduate School Department

Name: Allan M. Manaloto, RN Professor: Dr. Amelia Sta. Maria

Subject: Advanced Pathophysiology Date: November 09, 2013

I N F E C T I O N

Learning Objectives:

I. Understand basic concepts of Infection.

II. Apply required knowledge in preventing and/or minimizing infection.

III. Perform appropriate behaviors required to prevent health care associated

infections.

IV. Demonstrate required competence to provide patients with safe care.

I. I N T R O D U C T I O N

Modern healthcare has shown great progress in preventing and treating

infectious diseases. In developed countries, they have sanitary (better) living

conditions, clean water, uncontaminated food, vaccinations, and antimicrobials.

Many microorganisms find human body to be hospitable site to grow and flourish,

provided with nutrients and appropriate temperature and humidity. In many cases,

a mutual relationship exists, in which humans and the microorganisms benefit. This

is maintained by inflammatory and immune systems. If this 2 compromised,

microorganisms leave their normal sites and cause infection.

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II. CONCEPT OF INFECTION

1. Innate Host (body) Resistance

a.) First line: External barriers (skin & mucous membrane)

b.) Second line: Inflammatory Response

c.) Third line: Immune System

2. Chain of Infection

Infections are spread through a process known as chain of infection.

a.) Causative Organism

→there must 1st be a pathogen: bacteria, virus, fungi, and protozoa.

b.)Reservoir/ Source of the pathogen

→term use for any person, plant, animal, substances, or location that

provides nourishment for M.O.

→ Nurse: Disinfect/ Sterilized equipments, and environmental sanitation.

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•Living Reservoir

-Humans: most important reservoir

-Animals: Zoonotic dse-infectious disease that human acquired from

animals.

•Non-Living Reservoir

-Air, soil, dust, food, fomites

c.) Portal of Exit

→way for the pathogen to escape from reservoir. (eg. secretions, excretions,

skin, droplets).

→Nurse: Hand Hygiene, Control excretion, Proper waste disposal.

d.) Mode of Transmission (MOT)

→way for the pathogen to travel; Connect the infectious source to the new

host;

→specific organism requires specific route of transmission for infection to

occur.

→Nurse: Hand hygiene, Standard precaution, Isolation, and food handling.

MOT is transported to host in ways:

•Contact:

- Direct skin-skin contact (ex. Handshaking)- most prevalent MOT

- Direct mucous mem (ex. Kissing/ Sexual intercourse)

•Airborne

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- Travels long distances (e.g. M. TB); most contagious airborne diseases

are caused by respiratory pathogens carried to susceptible people in

droplets of respiratory secretions. (ex. Colds, influenza, measles,

chicken pox)

•Droplets

-large particles enter the air and drop due to weight. Transmitted via

coughing/ sneezing . The infected pt must be near the host.

•Vector-Borne

-usually not in hospital settings; various types of biting insects and

arachnids; They transfer pathogens from infected person to another (bites).

•Vehicles/ Vehicular

-contaminated inanimate object- food, water, dust, fomites. (by secretion

urine,blood, feces, exudates)

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e.) Portal of Entry

- how the M.O enter to a susceptible hosts. Mucus mem, GIT, GUT, broken

skin.

- Nurse: Catheterization care, wound care, Aseptic technique

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f.) Susceptible host

- for infection to occur, the new host must be susceptible! They are:

•Infants-immune system not mature, immunization not yet completed

•Elderly-altered immune response due to aging; thin skin.

•Lifestyle- promiscuity; drug and alcohol use

•Occupation- healthcare worker

•Medications- immunosuppresants

•Conditions such as burns, surgery, etc.

-Nurse: Treat the underlying cause, and recognition of high risk patient.

3. Signs and Symptoms of Infection

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TERMS TO KNOW…

*Health-care acquired infection (HAI): previously known as

nosocomial infection, infections acquired from healthcare facility.

Occurs 48-72 hours after admission.

TERMS TO KNOW…

*Community acquired infection (CAI): infection acquired in

community. Ct is admitted with/ develops signs and symptoms

24-48 hrs after admission.

*Infection: occurs when organism present in greater quantities

because of multiplying rapidly, causing host to become ill.

*Colonization: occurs when bacteria live within the body without

causing infection.

First sign of infection is Fever (but not always!). Other: are specific to site, ct’s

age, and pathogen.

Site of Infection Signs and Symptoms

Urine Urgency, frequency, dysuria, suprapubic tenderness

Wound Purulent drainage (pus), Inflammation

Lungs Rales, productive cough, chest pain, SOB

Blood Chills, hypotension, oliguria

CNS HA, dizziness, altered LOC, skin rash, agitation

GIT Diarrhea, bloody stools, N/V, diarrhea

4. Preventing Infection

The Hospital infection control practices committee (HICPAC) of the CDC

recommends 2 tier of isolation precaution:

A.) STANDARD PRECAUTION “Universal Precaution”

Precautions used on ‘Standard basis’/ All the time when caring for all clients to

prevent exposure to infectious disease.

Tenets: all clients are colonized/ infected with M.O whether or not there are

symptoms.

Applies: To all blood, all body fluids, secretions, excretions, non-intact skin, and

mucous membrane.

Purpose: Prevent transmission of nosocomial infection.

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•Hand Hygiene•

Measures include:

a.) Hand washing:

>with soap and water when hands are visibly soiled.

>It is the single most important measure to reduce the risks of transmitting

pathogens from patient to another.

>The friction created during washing removes M.O.

b.) Alcohol-Based hand Rubs:

>alternative to handwashing when hands are not visibly soiled. Efficacy and

convenience, but not sufficient to kill spores.

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NOTE: Do not wear artificial fingernails/ nail extenders.

• Personal Protective Equipment•

a.) Gloves

>wear when in contact with blood/ body fluids.

>Wash hands after using gloves. Latex gloves are preferred than vinyl.

b.) Gown

>prevent soiling of your clothes; if your clothes are soiled, it must laundered by

hospital prior taking home.

c.) Goggles

>for eye protection-for spitting and coughing client. Also wear when suctioning

patient, procedures that may cause splashing.

d.) Mask

>for ct who is coughing/ risk of splashing; when client is on Respi isolation

precaution.

e.) Caps and Shoe Covers

>protect client from hair of healthcare professional/ OR procedure.

•Needle Stick Prevention•

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>reduces risk of blood-borne infection; Extreme care when handling needles,

scalpels/ sharps.

>Used needle should not be recapped.

B.) TRANSMISSION-BASED PRECAUTION

Precautions in addition to Standard precaution for some microbes that are so

contagious. Perform hand hygiene before and after contact.

•Airborne Precaution•

>For diseases transmitted through air. (Ex. Chickenpox, TB, Measles)

>Client should be kept in Negative-Pressure room (source isolation) to keep the air

in client’s room when the door is opened.

>when client is to be transported to another hospital, surgical mask is placed on ct.

•Droplet Precaution•

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>droplets are heavy, they fall on ground. Therefore keep an arm’s length distance

from person coughing.

>Examples of diseases: Pneumonia MDR, Pertusis, Influenza, Mumps

>Wear surgical mask when caring for patient.

>pt is placed in private room/ if not available, room with the pt having active

infection with the same pathogen but with no other infection.

>special air-handling/ ventilation is not required.

>pt wear surgical mask when transported.

•Contact Precaution•

>used in diseases MRSA, Shigella, Lice, Scabies, Major draining abscesses,

incontinent diapered client.

>require use of gowns and gloves in illnesses involving skin, illnesses transmitted

via fecal-oral route, direct-indirect contact illnesses.

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>clients have dedicated equipment like BP, Stetoscope, Thermometer.

>most frequent MOT; Pt placed in private room; Limit pt transport.

IV. C O N C L U S I O N

Hospital acquired infections are a threat to population health and are not going

away any time soon. Due to frequent contact between health care workers and

patients, pathogens can be transmitted from one patient to another if good quality

hand hygiene is not maintained. It is the responsibility of health care workers to

keep the patients in their care safe by modeling effective and frequent hand

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washing practices.  Nurses need to have a proactive voice in the promotion of

current best practices for hand washing hygiene.

V. R E F E R E N C E S

→Understanding Pathophysiology, 3rd Edition (S. Huether & K. McCance)

→Brunner and Suddarth’s Textbook of MSN, 11th Edition

→Hurst Reviews (Pathophysiology Review)

→Burton’s Microbiology

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