Infection Prevention & Control

After tissues are injured, a series of well-coordinated events occurs. The inflammatory response includes the following:

1 Vascular and cellular responses 2 Formation of inflammatory exudates (fluid and cells that are discharged from cells or blood vessels [e.g., pus or serum]) 3 Tissue repair

Identify the alterations in health that increase the risk of infection.

1. risk factors 2. possible existing infections 3. medications 4. stressors

What is the the body's main defenses against infection?

1. skin 2. mouth 3. eye 4. respiratory tract 5. urinary tract 6. gastrointestinal tract 7. vagina

Nursing Process: Planning

Common Goals of Care: Preventing exposure to infectious organisms Controlling or reducing extent of infection Maintaining resistance to infection Verbalizing understanding of infection prevention and control techniques Setting Priorities Teamwork and Collaboration

Bacteriocidal:

Destructive to bacteria.

Factors that Increase Infection Risk

Developmental stage Breaks in the skin Illness/injury, chronic disease Smoking, substance abuse Multiple sex partners Medications that inhibit/decrease immune response Nursing/medical procedures Age Nutritional Status Stress Disease Process Treatments or conditions that compromise the immune response

Endogenous infection

Endogenous infection occurs when part of the patient's flora becomes altered and an overgrowth results (e.g., staphylococci, enterococci, yeasts, and streptococci). This often happens when a patient receives broad-spectrum antibiotics that alter the normal floras. When sufficient numbers of microorganisms normally found in one body site move to another site, an endogenous infection develops. The number of microorganisms needed to cause a health care-associated infection depends on the virulence of the organism, the susceptibility of the host, and the body site affected.

Droplet precautions:

Focus on diseases that are transmitted by large droplets expelled into the air and travel 3 to 6 feet from the patient. Droplet precautions require the wearing of a surgical mask when within 3 feet of the patient, proper hand hygiene, and some dedicated-care equipment. An example is a patient with influenza.

TYPES OF HAI INFECTION

Iatrogenic infections exogenous infection Endogenous infection

Define the stages of an infection

Incubation Prodromal illness convalescence

What is a HAI (Health Care Associated Infection)?

Infection acquired following admission to a HC facility NOT present prior to admission -Nosocomial

Incubation

Interval between entrance of the pathogen into the body and appearance of first symptoms (e.g. chickenpox, 10-21 days after exposure)

Convalescence

Interval when acute symptoms of infection disappear. Recovery can take days or months.

Classifications of Infections

Location 1. Local (ie., UTI) 2. Systemic ( Affects many regions, spread by blood, lymph, etc.) Duration 1. Acute: rapid onset, short duration 2. Chronic: Slow development, long duration 3. Latent: No discernible symptoms (ie., HIV)

How Does the Body Defend Against Infection?

Normal body flora Body system defenses Inflammation

Surgical Asepsis

Patient preparation Sterile field: an area free of microorganisms and prepared to receive sterile items Principles Performing sterile procedures

Bacteriostasis:

Prevention of growth and reproduction of bacteria.

Protective environment:

Protective environment: Focuses on a very limited patient population. This form of isolation requires a specialized room with positive airflow. The airflow rate is set at greater than 12 air exchanges per hour, and all air is filtered through a HEPA filter. Patients are not allowed to have dried or fresh flowers or potted plants in these rooms

Nursing Process: Assessment

Review of systems Travel history Immunizations and vaccinations Medications Risk factors Stressors Clinical appearance Laboratory data

Implementation (contd.); Medical Asepsis

Standard Precautions (Tier 1): Applies to care of ALL patients ALL of the time. Hand hygiene Wear gloves when touching body fluids, mucous membranes or any contaminated surfaces. Wear PPE (Personal Protective Equipment) when contact w/blood or body fluids anticipated. Discard all contaminated sharp instruments and needles in sharps container. Respiratory hygiene/cough etiquette Transmission-based precautions: ISOLATION (Tier 2): Isolation= the separation and restriction of movement of ill persons with contagious diseases Airborne precautions (ie. TB) Droplet precautions (ie. influenza) Contact precautions Protective environment (ie. Immunocompromised patient) Isolation (Tier 2): Other Considerations: Psychological implications Isolation environment PPE Specimen collection Bagging of trash or linen Patient transport Psychological implications Isolation environment PPE Specimen collection Bagging of trash or linen Patient transport

Difference between symptomatic and asymptomatic infections

Symptomatic infection: if the pathogens multiply and cause clinical signs and symptoms asymptomatic infection: if clinical signs and symptoms are not present. Ex. HEP C can be asymptomatic, it is most efficiently transmitted thru direct passage of blood into the skin from a percutaneous exposure even if the source patient is asymptomatic.

Communicable disease

an infectious disease that can be transmitted from one person to another

Implementation (contd.): Surgical Asepsis

. Surgical asepsis: (sterile technique): Principles of Surgical Asepsis a. A sterile object remains sterile only when touched by another sterile object. b. Only sterile objects may be placed on a sterile field. c. A sterile object or field out of the range of vision or an object held below a person's waist is contaminated. d.A sterile object or field becomes contaminated by prolonged exposure to air. e.When sterile surfaces comes in contact with a wet, contaminated surface, the object or field becomes contaminated by capillary action. f.Fluid flows in the direction of gravity. g.The edges of a sterile field or container are considered contaminated.

What are the types of patient alterations in health that would require their use?

1. Airborne (TB, Rubeola, varicella) Negative pressure rooms (for TB) 2. Droplet (Other respiratory infections (eg. Rubella) 3. Contact Wounds (eg. MRSA, VRE, VISA

what are the various types of transmission based precautions?

1. Contact precautions:used for direct and indirect contact with patients and their environment. Direct contacts refers to the care and handling of contaminated body fluids. Ex. blood or other body fluids from an infected patient that enter the health care worker's body thru direct contact w/ compromised skin or mucuous membranes. indirect contact involves the transfer of an infectious agent thru a contaminated intermediate object such as contaminated instruments or hands of health care workers. The HC worker may transmit microorgs from one patient site to another if hand hygiene is not performed. 2. standard precautions: apply to contact with blood, body fluids, nonintact skin, and mucuous membranes from all patients. 3. Droplet precautions: focus on diseases that are transmitted by large droplets expelled into the air and travel 3-6 feet from the patient. Droplet precautions require the wearing of a surgical mask when within 3 ft of the patient , proper hygiene and some dedicated care equipment. Ex pt with influenza. 4. Airborne precautions: focus on diseases that are transmitted by smaller droplets, which remain in the air for longer periods of time. This requires a specially equipped room with a negative air flow referred to as an airborne infection isolation room. Air is not returned to the inside ventilation system but is filtered thru a high efficiency particulate air (HEPA) filter and exhausted directly to the outside. All health care personnel wear an N95 respirator every time they enter the room.

How do HAIs significantly increase costs of health care?

1. Extending hospital stays 2. Increased disability 3. Increased costs of antibiotics 4. Prolonged recovery times. HAIs costs are often not reimbursed by Medicare/Medicaid.

What are the elements of medical asepsis?

1. Hand hygiene, barrier techniques, and routine environmental cleaning. 2. Think home 3. "Clean Technique" Medical asepsis, or clean technique, includes procedures for reducing the number of organisms present and preventing the transfer of organisms. Hand hygiene, barrier techniques, and routine environmental cleaning are examples of medical asepsis.

What is the cycle of infection as it relates to the nursing care of patients?

1. Infectious agent or pathogen 2. a reservoir or source for the pathogen top grow 3. a port of exit from reservoir 4. a mode of transmission 5. a port of entry to a host 6. a suseptible host

What are common nursing diagnoses that are commonly used for the infected or at risk patient?

1. Risk for infection 2. imbalanced nutrition: less than body requirements 3. Impaired oral mucous membrane 4. social isolation 5. impaired tissue integrity 6. readiness for enhanced immunizations status

WBC c Differential

5,000-10,000/mm3 Neutrophils - 55%-70% Lymphocytes - 20%-40% Monocytes - 5%-10% Eosinophils - 1%-4% Basophils .5%-1.5%

Nursing implementation on aseptic techniques

Aseptic technique=practices/procedures that assist in reducing risk for infection 1. Medical asepsis: (clean technique) 2. Surgical asepsis: (sterile technique

What is the reservoir element of the chain of infection?

A reservoir is a place where microorganisms survive, multiply, and await transfer to a susceptible host. Common reservoirs are humans and animals (hosts), insects, food, water, and organic matter on inanimate surfaces (fomites). Frequent reservoirs for health care-associated infections (HAIs) include health care workers, especially their hands; patients; equipment; and the environment. Human reservoirs are divided into two types: those with acute or symptomatic disease and those who show no signs of disease but are carriers of it. Humans can transmit microorganisms in either case. Animals, food, water, insects, and inanimate objects can also be reservoirs for infectious organisms. To thrive, organisms require a proper environment, including appropriate food, oxygen, water, temperature, pH, and light

WHO is susceptible to HAIs?

ALL patients ALL health care workers NURSES have a higher occupational exposure than other HC professionals due to frequent patient contact!

The inflammatory response:Vascular and Cellular Responses

Acute inflammation is an immediate response to cellular injury. Rapid vasodilation occurs, allowing more blood near the location of the injury. The increase in local blood flow causes the redness and localized warmth at the site of inflammation. Injury causes tissue damage and possibly necrosis. As a result the body releases chemical mediators that increase the permeability of small blood vessels; and fluid, protein, and cells enter interstitial spaces. The accumulation of fluid appears as localized swelling (edema). Another sign of inflammation is pain. The swelling of inflamed tissues increases pressure on nerve endings, causing pain. As a result of physiological changes occurring with inflammation, the involved body part may have a temporary loss of function. For example, a localized infection of the hand causes the fingers to become swollen, painful, and discolored. Joints become stiff as a result of swelling, but function of the fingers returns when inflammation subsides. The cellular response of inflammation involves white blood cells (WBCs) arriving at the site. WBCs pass through blood vessels and into the tissues. Phagocytosis is a process that involves the destruction and absorption of bacteria. Through the process of phagocytosis, specialized WBCs, called neutrophils and monocytes, ingest and destroy microorganisms or other small particles. If inflammation becomes systemic, other signs and symptoms develop. Leukocytosis, or an increase in the number of circulating WBCs, is the response of the body to WBCs leaving blood vessels. A serum WBC count is normally 5,000 to 10,000/mm3 but typically rise to 15,000 to 20,000/mm3 and higher during inflammation. Fever is caused by phagocytic release of pyrogens from bacterial cells, which causes a rise in the hypothalamic set point (see Chapter 29).

Factors that Support Host Defenses

Adequate nutrition: to manufacture cells of the immune system. to replace lost stores; maintain production of WBCs and repair damaged tissues Balanced hygiene: sufficient to decrease skin bacterial count (not overzealous, as may cause skin cracking) Intact skin one of the best defenses against infection Rest/exercise: To rejuvenate and conserve strength; exercise: too little activity causes circulation to slow and lungs to supply less oxygen Reducing stress: stress decreases body's immune defense; laughing increases oxygenation, promoting body movement and increases immune response Immunization: Expose body to weakened or killed pathogens stimulating the immune response

exogenous infection

An exogenous infection comes from microorganisms found outside the individual such as Salmonella, Clostridium tetani, and Aspergillus. They do not exist as normal floras.

Common infectious agents

Bacteria: MRSA, C. Diff, VRE, TB, Pseudomonas, Neisseria gonorrhoeae, clostridium tetani Virus: HIV, Hepatitis A,B, C, or E, HPV, Ebola Fungus: Tinea pedis, candidiasis, histoplasmosis Parasite or Protozoa: Pneumocystis pneumonia, pediculosis, malaria, giardiasis

asepsis

Base efforts to minimize the onset and spread of infection on the principles of aseptic technique. Asepsis is the absence of pathogenic (disease-producing) microorganisms. Aseptic technique refers to practices/procedures that help reduce the risk for infection. The two types of aseptic technique are medical and surgical asepsis.

Nursing Process: Implementation

Consider: Medical and surgical asepsis Control or elimination of infectious agents Control or elimination of reservoirs Control of portals of entry Control of transmission Hand hygiene Isolation precautions Health promotion: Preventing an infection from developing or spreading Acute care of patient with infection: Eliminating infectious organisms, supporting the patient's defenses. Be aware that various cultural and religious beliefs or practices influence patients' decisions to seek treatment for an infection or to use methods to prevent infection. THE single most important strategy for preventing infections: hand hygiene

Cough Etiquette

Cover your nose/mouth with a tissue when you cough, and promptly dispose of the contaminated tissue. Place a surgical mask on a patient if it does not compromise respiratory function or is applicable; ( may not be feasible in pediatric populations.) Hand hygiene after contact with respiratory secretions! Maintain separation of 3 feet or > from persons with URI.

disinfection and sterilization

Disinfection describes a process that eliminates many or all microorganisms, with the exception of bacterial spores, from inanimate objects (Rutala and Weber, 2008, 2009). There are two types of disinfection: the disinfection of surfaces and high-level disinfection, which is required for some patient care items such as endoscopes and bronchoscopes. You accomplish disinfection using a chemical disinfectant or wet pasteurization (used for respiratory therapy equipment). Examples of disinfectants are alcohols, chlorines, glutaraldehydes, hydrogen peroxide, and phenols. Glutaraldehydes are caustic and toxic to tissues and pose a potential health risk. Sterilization is the complete elimination or destruction of all microorganisms, including spores. Steam under pressure, ethylene oxide (ETO) gas, hydrogen peroxide plasma, and chemicals are the most common sterilizing agents. ETO poses a potential health risk to staff processing with this agent, and exposure must be monitored.

Nursing Diagnosis

During assessment gather objective data such as inspection of an open incision or a reduced caloric intake record and subjective data such as a patient's complaint of tenderness over a surgical wound site. Review the data carefully, looking for clusters of defining characteristics or risk factors that create a pattern. This pattern suggests a specific nursing diagnosis (Box 28-6). The following are examples of nursing diagnoses that often apply: •Risk for infection •Imbalanced nutrition: less than body requirements •Impaired oral mucous membrane •Risk for impaired skin integrity •Social isolation •Impaired tissue integrity •Readiness for enhanced immunization status

What is the modes of transmission element of the chain of infection?

Each disease has its own specific mode. Preventative measure: practicing infection prevention and control techniques such as hand hygiene you interrupt the mode of transmission. A microorg is sometimes transmitted by more than 1 route. Ex. chicken pox is spread by airborne route and droplet nuclei or direct contact. The major route of transmission id in healthcare settings is the unwashed hands of the health care providers. Equipment use also becomes a source. Direct • Person-to-person (fecal, oral) physical contact between source and susceptible host (e.g., touching patient feces and then touching your inner mouth or consuming Contaminated food) Indirect . Personal contact of susceptible host with contaminated inanimate object (e.g., needles or sharp objects, dressings, environment) Droplet • Large particles that travel up to 3 feet during coughing, sneezing, or talking and come in contact with susceptible host Airborne • Droplet nuclei or residue or evaporated droplets suspended in air during coughing or sneezing or carried on dust particles Vehicles • Contaminated items • Water • Drugs, solutions • Blood • Food (improperly handled, stored, or cooked; fresh or thawed meats) Vector • External mechanical transfer (flies) • Internal transmission such as parasitic conditions between vector and host such as: •Mosquito •Louse •Flea •Tick

Airborne precautions:

Focus on diseases that are transmitted by smaller droplets, which remain in the air for longer periods of time. This requires a specially equipped room with a negative air flow referred to as an airborne infection isolation room. Air is not returned to the inside ventilation system but is filtered through a high-efficiency particulate air (HEPA) filter and exhausted directly to the outside. All health care personnel wear an N95 respirator every time they enter the room.

Iatrogenic infections

Iatrogenic infections are a type of HAI from a diagnostic or therapeutic procedure. For example, procedures such as a bronchoscopy and treatment with broad-spectrum antibiotics increase the risk for certain infections (Arnold, 2009; Stricof, 2009). Use critical thinking when practicing aseptic techniques and follow basic infection prevention and control policies and procedures to reduce the risk of HAIs. Always consider the patient's risks for infection and anticipate how the approach to care increases or decreases the risk.

Course of Infection by Stage

Incubation Period Interval between entrance of pathogen into body and appearance of first symptoms (e.g., chickenpox, 10 to 21 days after exposure; common cold, 1 to 2 days; influenza, 1 to 5 days; mumps, 12 to 26 days). Prodromal Stage Interval from onset of nonspecific signs and symptoms (malaise, low-grade fever, fatigue) to more specific symptoms. (During this time microorganisms grow and multiply, and patient may be capable of spreading disease to others.) For example, herpes simplex begins with itching and tingling at the site before the lesion appears. Illness Stage Interval when patient manifests signs and symptoms specific to type of infection. For example, strep throat is manifested by sore throat, pain, and swelling; mumps is manifested by high fever, parotid and salivary gland swelling. Convalescence Interval when acute symptoms of infection disappear. (Length of recovery depends on severity of infection and patient's host resistance; recovery may take several days to months.)

Evaluation

Measure patient outcomes: Absence of fever or wound infection, degree of wound healing, monitor for signs and symptoms of infection) Compare patient's actual response w/expected outcomes If goals not achieved, determine what steps must be taken. Exposure Issues: Patients AND health care workers are at risk for acquiring infection from accidental needlesticks: REPORT ANY CONTAMINATED NEEDLESTICK IMMEDIATELY. Follow-up begins with source patient testing. (Access to testing the source patient is stated in the testing law for each state.)

The inflammatory response:Inflammatory Exudate

Inflammatory Exudate Accumulation of fluid and dead tissue cells and WBCs forms an exudate at the site of inflammation. Exudate may be serous (clear, like plasma), sanguineous (containing red blood cells), or purulent (containing WBCs and bacteria). Usually the exudate is cleared away through lymphatic drainage. Platelets and plasma proteins such as fibrinogen form a meshlike matrix at the site of inflammation to prevent its spread.

Prodromal

Interval from onset of nonspecific signs and symptoms (malaise, fever, fatigue) to more specific. The stage were organisms multiple and grow and capable of spreading.

Illness

Interval when patient manifests signs and symptoms specific to the type of infection. strep throat.

hand hygiene: implementation

Preferred method is use of alcohol hand gel Use soap and water when hands visibly soiled and if patient has c. difficele. Wash hands: before/after direct patient contact, before/after donning sterile gloves, before/after eating, using restroom, after coughing, sneezing, blowing nose. DO NOT use artificial nails, colored nail polish. Use only hospital-approved lotion Patient safety Separate personal care items Handling solid and fluid waste Wound cleaning Patient education Cough etiquette Isolation and isolation precautions Surgical asepsis

Health care-associated infections (HAIs)

Patients in health care settings, especially hospitals and long-term care facilities, have an increased risk of acquiring infections. Health care-associated infections (HAIs), formerly called nosocomial or health care-acquired infections, result from the delivery of health services in a health care facility. They occur as the result of invasive procedures, antibiotic administration, the presence of multidrug-resistant organisms, and breaks in infection prevention and control activities. Patients who develop HAIs often have multiple illnesses, are older adults, and are poorly nourished; thus they are more susceptible to infections. In addition, many patients have a lowered resistance to infection because of underlying medical conditions (e.g., diabetes mellitus or malignancies) that impair or damage the immune response of the body. Invasive treatment devices such as intravenous (IV) catheters or indwelling urinary catheters impair or bypass the natural defenses of the body against microorganisms. Critical illness increases patients' susceptibility to infections, especially multidrug-resistant bacteria. Meticulous hand hygiene practices, the use of chlorhexidine washes, and other advances in intensive care unit (ICU) infection prevention help to prevent these infections Risk Factors # of HC workers with direct contact with the patient Types and numbers of invasive procedures Therapy received LOS Major sites for HAI infection Surgical or truamatic wounds Urinary and respiratory tracts Bloodstream

The Isolation Environment

Private rooms used for isolation sometimes provide negative-pressure airflow to prevent infectious particles from flowing out of a room to other rooms and the air handling system. Special rooms with positive-pressure airflow are also used for highly susceptible immunocompromised patients such as recipients of transplanted organs. On the door or wall outside the room the nurse posts a card listing precautions for the isolation category in use according to health care facility policy. The card is a handy reference for health care personnel and visitors and alerts anyone who might enter the room accidentally that special precautions must be followed. The isolation room or an adjoining anteroom needs to contain hand hygiene and PPE supplies. Soap and antiseptic (antimicrobial) solutions need to be available. Personnel and visitors perform hand hygiene before approaching the patient's bedside and again before leaving the room. If toilet facilities are unavailable, there are special procedures for handling portable commodes, bedpans, or urinals. All patient care rooms, including those used for isolation; contain an impervious bag for soiled or contaminated linen and a trash container with plastic liners. Impervious receptacles prevent transmission of microorganisms by preventing leaking and soiling of the outside surface. A disposable rigid container needs to be available in the room to discard used sharps such as safety needles and syringes. Remain aware of infection prevention and control techniques while working with patients in protected environments. You need to feel comfortable performing all procedures and yet remain conscious of infection prevention and control principles. Depending on the microorganism and mode of transmission, evaluate which articles or equipment to take into an isolation room. For example, the CDC (2007) recommends the dedicated use of articles such as stethoscopes, sphygmomanometers, or rectal thermometers in the isolation room of a patient infected or colonized with vancomycin-resistant enterococci. Do not use these devices on other patients unless they are first adequately cleaned and disinfected. Box 28-12 describes the procedures to perform when using shared equipment.

Surgical asepsis

Surgical asepsis or sterile technique prevents contamination of an open wound, serves to isolate the operative area from the unsterile environment, and maintains a sterile field for surgery. Surgical asepsis includes procedures used to eliminate all microorganisms, including pathogens and spores, from an object or area (Rutala and Weber, 2008, 2009). In surgical asepsis an area or object is considered contaminated if touched by any object that is not sterile. It demands the highest level of aseptic technique and requires that all areas be kept free of infectious microorganisms. Use surgical asepsis in the following situations: •During procedures that require intentional perforation of the patient's skin such as insertion of IV catheters or central lines •When the integrity of the skin is broken as a result of trauma, surgical incision, or burns •During procedures that involve insertion of catheters or surgical instruments into sterile body cavities such as insertion of a urinary catheter Although surgical asepsis is common in the operating room, labor and delivery area, and major diagnostic areas, you also use surgical aseptic techniques at the patient's bedside (e.g., when inserting IV or urinary catheters, suctioning the tracheobronchial airway, and reapplying sterile dressings). A nurse in an operating room follows a series of steps to maintain sterile technique, including applying a mask, protective eyewear, and a cap; performing a surgical hand scrub; and applying a sterile gown and gloves. In contrast, a nurse performing a dressing change at a patient's bedside only performs hand hygiene and applies sterile gloves. For certain procedures (e.g., changing a central line dressing) the nurse also uses a mask. Regardless of the procedures followed or the setting, the nurse always recognizes the importance of strict adherence to aseptic principles

Contact precautions:

Used for direct and indirect contact with patients and their environment. Direct contact refers to the care and handling of contaminated body fluids. An example includes blood or other body fluids from an infected patient that enter the health care worker's body through direct contact with compromised skin or mucous membranes. Indirect contact involves the transfer of an infectious agent through a contaminated intermediate object such as contaminated instruments or hands of health care workers. The health care worker may transmit microorganisms from one patient site to another if hand hygiene is not performed between patients

Normal Floras

The body normally contains microorganisms that reside on the surface and deep layers of skin, in the saliva and oral mucosa, and in the gastrointestinal and genitourinary tracts. A person normally excretes trillions of microbes daily through the intestines. Normal floras do not usually cause disease when residing in their usual area of the body but instead participate in maintaining health. Normal floras of the large intestine exist in large numbers without causing illness. They also secrete antibacterial substances within the walls of the intestine. The normal floras of the skin exert a protective, bactericidal action that kills organisms landing on the skin. The mouth and pharynx are also protected by floras that impair growth of invading microbes. Normal floras maintain a sensitive balance with other microorganisms to prevent infection. Any factor that disrupts this balance places a person at increased risk for acquiring a disease. For example, the use of broad-spectrum antibiotics for the treatment of infection can lead to suprainfection. A suprainfection develops when broad-spectrum antibiotics eliminate a wide range of normal flora organisms, not just those causing infection. When normal bacterial floras are eliminated, body defenses are reduced, which allows for disease-producing microorganisms to multiply, causing illness

Inflammation

The cellular response of the body to injury, infection, or irritation is termed inflammation. Inflammation is a protective vascular reaction that delivers fluid, blood products, and nutrients to an area of injury. The process neutralizes and eliminates pathogens or dead (necrotic) tissues and establishes a means of repairing body cells and tissues. Signs of localized inflammation include swelling, redness, heat, pain or tenderness, and loss of function in the affected body part. When inflammation becomes systemic, other signs and symptoms develop, including fever, leukocytosis, malaise, anorexia, nausea, vomiting, lymph node enlargement, or organ failure. Physical agents, chemical agents, or microorganisms trigger the inflammatory response. Mechanical trauma, temperature extremes, and radiation are examples of physical agents. Chemical agents include external and internal irritants such as harsh poisons or gastric acid. Sometimes microorganisms also trigger this response.

The chain of infection

The presence of a pathogen does not mean that an infection will occur. Infection occurs in a cycle that depends on the presence of all of the following elements: •An infectious agent or pathogen •A reservoir or source for pathogen growth •A port of exit from the reservoir •A mode of transmission •A port of entry to a host •A susceptible host (Infectious agent, reservoir, portal of exit, mode of transmission, portal of entry, host.) * an infection can develop if this chain remains uninterrupted. Preventing infections involves breaking the chain of infection.

Isolation gowns

The primary reason for gowning is to prevent soiling clothes during contact with a patient. Gowns or cover-ups protect health care personnel and visitors from coming in contact with infected material and blood or body fluids. Gowns are often required depending on the expected amount of exposure to infectious material. Gowns used for barrier protection are made of a fluid-resistant material. Change gowns immediately if damaged or heavily contaminated. Isolation gowns are disposable or reusable. Isolation gowns usually open at the back and have ties or snaps at the neck and waist to keep the gown closed and secure. Gowns need to be long enough to cover all outer garments. Long sleeves with tight-fitting cuffs provide added protection. No special technique is required for applying clean gowns as long as they are fastened securely. However, carefully remove gowns to minimize contamination of the hands and uniform and discard them after removal

clinical appearance

The signs and symptoms of infection may be local or systemic. Localized infections are most common in areas of skin or mucous membrane breakdown such as surgical and traumatic wounds, pressure ulcers, oral lesions, and abscesses. To assess an area for localized infection, first inspect it for redness and swelling caused by inflammation. Because there may be drainage from open lesions or wounds, wear clean gloves. Infected drainage may be yellow, green, or brown, depending on the pathogen. For example, green nasal secretions often indicate a sinus infection. Ask the patient about pain or tenderness around the site. Some patients complain of tightness and pain caused by edema. If the infected area is large enough, movement is restricted. Gentle palpation of an infected area usually results in some degree of tenderness. Wear protective eyewear and a surgical mask when there is a risk for splash or spray with blood or body fluids. Systemic infections cause more generalized symptoms than local infection. These symptoms often include fever, fatigue, nausea/vomiting, and malaise. Lymph nodes that drain the area of infection often become enlarged, swollen, and tender during palpation. For example, an abscess in the peritoneal cavity causes enlargement of lymph nodes in the groin. An infection of the upper respiratory tract causes cervical lymph node enlargement. If an infection is serious and widespread, all major lymph nodes may enlarge. Systemic infections sometimes develop after treatment for localized infection has failed. Be alert for changes in the patient's level of activity and responsiveness. As systemic infections develop, an elevation in body temperature can lead to episodes of increased heart and respiratory rates and low blood pressure. Involvement of major body systems produces specific symptoms. For example, a pulmonary infection results in a productive cough with purulent sputum. A UTI results in cloudy, foul-smelling urine.

respiratory protection

Wear full-face protection (with eyes, nose, and mouth covered) when you anticipate splashing or spraying of blood or body fluid into the face. Also wear masks when working with a patient placed on airborne or droplet precautions. If the patient is on airborne precautions for TB, apply an OSHA-approved respirator-style mask. The mask protects the nurse from inhaling microorganisms and small-particle droplet nuclei that remain suspended in the air from a patient's respiratory tract. The surgical mask protects a wearer from inhaling large-particle aerosols that travel short distances (3 feet). When caring for patients on droplet or airborne precautions, apply a mask (surgical or respirator) when entering the isolation room. At times a patient who is susceptible to infection wears a mask to prevent inhalation of pathogens. Patients on droplet or airborne precautions who are transported outside of their rooms need to wear a surgical mask to protect other patients and personnel. Masks prevent transmission of infection by direct contact with mucous membranes (CDC, 2005a). A mask discourages the wearer from touching the eyes, nose, or mouth (Box 28-13). A properly applied mask fits snugly over the mouth and nose so pathogens and body fluids cannot enter or escape through the sides. If a person wears glasses, the top edge of the mask fits below the glasses so they do not cloud over as the person exhales. Keep talking to a minimum while wearing a mask to reduce respiratory airflow. A mask that has become moist does not provide a barrier to microorganisms and is ineffective. You need to discard it. Never reuse a disposable mask. Warn patients and family members that a mask can cause a sensation of smothering. If family members become uncomfortable, they should leave the room and discard the mask. Specially fitted respiratory protective devices (N95 respirator masks) are required when caring for patients on airborne precautions, such as patients with known or suspected TB (Fig. 28-3) (CDC, 2005a). The mask must have a higher filtration rating than regular surgical masks and be fitted snugly to prevent leakage around the sides. Be aware of health care facility policy regarding the type of respiratory protective device required. Special fit testing is required to establish the size and ability of the nurse to wear this type of mask (CDC, 2005a).

The inflammatory response:Tissue Repair

When there is injury to tissue cells, healing involves the defensive, reconstructive, and maturative stages (see Chapter 48). Damaged cells are eventually replaced with healthy new cells. The new cells undergo a gradual maturation until they take on the same structural characteristics and appearance as the previous cells. If inflammation is chronic, tissue defects sometimes fill with fragile granulation tissue. Granulation tissue is not as strong as tissue collagen and assumes the form of scar tissue.

Standard precautions

You will learn to follow certain principles and procedures, including standard precautions, to prevent and control infection and its spread. Standard precautions apply to contact with blood, body fluid, nonintact skin, and mucous membranes from all patients. These precautions protect the patient and provide protection for the health care worker. A major component of patient and worker protection is hand hygiene (Skill 28-1, pp. 425-427). Hand hygiene includes using an instant alcohol hand antiseptic before and after providing patient care, washing hands with soap and water when they are visibly soiled, and performing a surgical scrub. Handwashing is the act of washing hands with soap and water, followed by rinsing under a stream of water for 15 seconds (CDC, 2002). The friction of rubbing hands together removes soil and transient organisms from the hands.

What is the port of exit element of the chain of infection?

after microorganisms find a site to grow and multiply they need to find a port of exit if they are to enter another host and cause disease. ports of exit include sites such as : blood, skin, mucuous membranes, respiratory tratc, genitourinary tract, gastrointestinal tract, and transplacental. Skin: is a port of entry bc any break in the integrity of the skin and mucuous membranes allows pathogens to exit the body. This may be exhibited by the creation of purulent drainage. The presence of purulent drainage is a potential port of exit. Respiratory tract: pathogens that infect the respiratory tract such as influenza virus are released from the body when an infected person sneezes or coughs. urinary tract: normally urine is sterile. Hw when a patient has a UTI microorganisms exit during. gastrointestinal tract: the mouth is one of the most bacterially contaminated sites of of the human body but most of the organisms are normal floras. Organisms that are normal floras in 1 person can be pathogens in another. EX. organisms exit when a person expectorates saliva. In addition, gastrointestinal ports of exit include bowel elimination, drainage of bile via surgical wounds, or drainage tubes. reproductive tract: organisms such as Neisseria gonorrhoeae and HIV exit through a man's urethral meatus or a woman's vaginal canal during sexual contact. Blood: is normally sterile; but in the case of communicable diseases such as hepatitis B or C or HIV, it becomes a reservoir for pathogens.

Port of entry

organisms enter the body thru the same routes they use for exiting. Ex, when a needle pierces a patient's skin, organisms enter the body if proper skin preparation is not first preformed. Factors such as depressed immune systems that reduce body defenses enhance the chances of pathogens entering the body.

How do healthcare workers protect themselves from coming into contact with infectious material, sharp injuries, and/ or exposure to a communicable disease?

by applying knowledge of the infectious process and using appropriate personal protective equipment. Diseases such as HEP B and C, HIV/AIDS, TB, and multidrug resistant organisms require a greater emphasis on infection prevention and control techniques.

To control organisms exiting via the respiratory tract, cover your mouth or nose when coughing or sneezing. Teach patients, health care staff, patient's families, and visitors respiratory hygiene....or

cough etiquette

Organisms require what in order to survive?

food: microorganisms require nourishment. Clostridium prefingens the microbe that cause gangrene thrive on organic matter. E. coli consume material such as soil. Oxygen: Aerobic bacteria require oxygen for survival and for multiplication sufficient to cause disease. Aerobic organisms cause more infections in humans than anaerobic organisms. An example of an aerobic organism is Staphylococcus aureus. Anaerobic bacteria thrive where little or no free oxygen is available. Infections deep within the pleural cavity, in a joint, or in a deep sinus tract are typically caused by anaerobes. An example of an anaerobic organism is Clostridium difficile, an organism that causes antibiotic-induced diarrhea. water: most organisms require water or moisture for survival. Ex. a freq place for microorganisms is the moist drainage from a surgical wound. Some bacteria assume a form called a spore which is resistant to drying. C difficile is spore like and causes antibiotic induced diarrhea. temperature:Microorganisms can live only in certain temperature ranges. Each species of bacteria has a specific temperature at which it grows best. The ideal temperature for most human pathogens is 20° to 43° C (68° to 109° F). For example, Legionella pneumophila grows best in water at 25° to 42° C (77° to 108° F) (. Cold temperatures tend to prevent growth and reproduction of bacteria (bacteriostasis). A temperature or chemical that destroys bacteria is bactericidal. pH: the acidity of an environment determines the viability of microorganisms. most microorgs prefer an environment within a pH range of 5.0 -7.0. bacteria thrive in urine with an alkaline pH. Light:microorganisms thrive in dark environments e.g under dressings and w/in body cavities.

infectious process

if an infection is localized- the patient usually experience localized symptoms such as pain, tenderness, and redness, at the wound site. use standard precautions, appropriate PPE, and hand hygiene when assessing the wound. use these precautions and hand hygiene blocks the spread of infection to other sites or other patients. An infection that affects the entire body instead of just a single organ or part is systemic and can become fatal if undetected and untreated.

What is the infectious agent element of the chain of infection? How to prevent infection in the infectious agent element of the chain of infection.

microorganisms include bacteria, viruses, fungi, and protozoa. Microorganisms on the skin are either resident or transient flora. Resident organisms ( normal flora): are permanent residents of the skin, where they survive, and multiply without causing illness. The potential for microorganisms to cause disease depends on the number of microorgs present. Resident skin microorgs are not virulent. Hw they sometimes cause serious infection when surgery or other invasive procedures allow them to enter deep tissues or when pt is severely immunocompromised. Transient organisms: attach to the skin when a person has contact w/ another person or object during normal activities. EX: when you touch a contaminated gauze transient bacteria adhere to your skin. Preventative measure:These organisms can be readily transmitted unless removed using hand hygiene.

Personal Protective Equipment PPE,

specialized clothing or equipment worn by a health care worker for protection against infectious materials (gowns, masks or respirators, protective eyewear, and gloves), should be readily available for personnel performing patient care (CDC, 2004). The equipment to be used is task based.

What is the susceptible hosts element of the chain of infection?

susceptibility to an infectious agent depends on the individual's degree of resistance to pathogens. Although everyone is constantly in contact with large numbers of microorg and infection does not develop until an individual becomes susceptible to the strength and numbers of microorg. A person's natural defenses against infection and certain risk factors ( age, nutritional status, presence of chronic disease, trauma, and smoking) affect susceptibility ( resistance) Hosts include:Multiple illnesses Older adult Poorly nourished Lowered resistance to infection Stress

virulence

the ability of microorgs to produce disease; ability to enter and survive in the host, and the susceptibility of the host.

What is an infection?

the invasion of a susceptible host by pathogens or microorganisms resulting in disease. * Only results if the pathogen multiplies and alters normal tissue function. It is different from a colonization in which a colonization is the presence and growth of microorganisms within a host but without tissue invasion or damage. some infectious disease such as meningitis, and pneumonia have a low or no risk for transmission. Although it may be serious for the patient they do not pose a risk to others including caregivers.