Study Guide - Infection Control

Study Guide – Infection Control 1. Definitions a. Innate Immunity – present at birth and is the primary defense system i. Nonspecific response involving white blood cells, neutrophils, and monocytes, not antigen specific so it responds quickly without prior exposure b. Acquired immunity – development of immunity actively or passively, can be natural through a disease or artificial through an immunization i. Active acquired immunity – development of antibodies to combat a specific foreign substance, as in vaccination or after illness, more exposure creates a more rapid and strong response ii. Passive acquired immunity – when a person gets antibodies rather than making them, naturally through the placenta as a fetus or artificially through gamma globulin injections, short lived c. Hypersensitivity reactions – overactive response against invaders or its own tissue, often called autoimmune diseases when the body attacks itself, like sepsis d. Disseminated infection – spread to other areas outside the initial site of infection e. Emerging Infections – infectious diseases that increase in incidence, can originate from changes in disease, contact with animals, or biologic warfare f. Reemerging infections – when a near eradication of some infections have occurred through vaccinations and proper medications, but it can resurge g. Hospital acquired infections – infections as a result of exposure to a microbe in a health care setting, about 2 million per year, half of which are antibiotic resistant, 1/3 are preventable and occur through patient contact, handwashing and PPE is essential to stop HAI’s, h. Infection – invasion of susceptible host by pathogens or microorganisms moving into the tissues resulting in disease i. Colonization – presence and growth of microorganisms within a host but without tissue invasion or damage, disease is caused only when pathogens multiply and alter normal tissue function of the host j. Communicable disease – if the disease can be transmitted directly from one person to the other by direct or indirect contact k. Iatrogenic infections – HAI from a diagnostic of therapeutic procedure like surgery, IV, foley, or anything else we DO to a patient (I PLACED IT) l. Exogenous infections – come from microbes outside the individual, they are not normal floras, normally pathogens shed from the body like blood or body fluids from others cross contaminating (CROSS CONTAMINATION) m. Endogenous infection occurs when part of patients flora becomes overgrown, typically because of broad spectrum antibiotics when n. o. p. q. r. s. t. u. v. normal flora overgrow and move to different parts of the body (ENDO – OVERGROW) Disinfection -- eliminates many or all microbes with exception of bacterial spores from inanimate objects, alcohols, chlorine, hydrogen peroxide Virulence—ability to produce disease Aerobic bacteria – require oxygen for survival and for multiplication sufficient to cause disease Anaerobic bacteria – thrive where little or no free oxygen is available Bacteriostasis – prevention of growth and reproduction of bacteria Bacteriacidal – destructive to bacteria Normal Flora – bacteria native to our bodies that don’t hurt us, provide an antibacterial substance released to combat infections Inflammation – protective cellular and vascular rxn that neutralizes pathogens and repairs body cells Sterilization: the complete elimination or destruction of all microorganisms, including spores, steam under pressure, ethylene oxide gas, other chemicals 2. Explain the infection cycle. a. Infectious agent or pathogen  reservoir or source for pathogen to grow  port of exit from the reservoir  mode of transmission  port of entry to host  susceptible host b. Reservoir – place where microorganisms survive, multiply, and await transfer to susceptible host, commonly food/animals/humans/insects/organic matter on surfaces, humans can be symptomatic disease or carriers of disease c. Portal of entry and exit is usually the same 3. Stages of the infectious process a. Incubation period – time between exposure and first symptoms, typically when viruses are passed the most because pt is asymptomatic i. Chicken pox 10-21 days ii. Common cold 2-3 days iii. Mumps 12-26 days b. Podromal Stage – non-specific symptoms present prior to specific s/s, the most contagious time period, ex: tingling before sores come on herpes outbreak c. Illness stage—manifest specific s/s of disease, ex: sore throat for strep throat d. Convalescent period – trying to recover after the illness stage is gone, can take several weeks 4. Identify the body’s defense against infection. a. Skin – intact and multi layered skin is the first line of defense, provides barrier, shedding of outer layers removes organisms, failure to bathe and improper hand washing can reduce effectiveness of this barrier, cuts and wounds can also reduce protection, sebum is a fatty acid produced by skin that kills some bacteria, excessive bathing reduces this protection b. Mouth – multi layered mucosa provides mechanical barrier, cuts, trauma, and extracted teeth reduce this barrier, saliva washes away particles containing microbes and contains microbial inhibitors, dehydration and poor oral hygiene are important to keep this barrier intact c. Eyes – tears and blinking are mechanisms to reduce entry or wash away particles, injury or splash exposure can damage the effectiveness of this barrier d. Respiratory tract – cilia in upper airway traps inhaled microbes and sweeps away microbes trapped in mucous, smoking, decreased humidity, or cold air all hinder this mechanism, macrophages engulf and destroy microbes that reach lung alveoli, smoking damages this potential e. Urinary tract – flushing of urine flow washes away microbes lining bladder and urethra, obstruction of normal flow/catheters/delayed urination all set up opportunity for infection, intact epithelium provides a barrier to microbes f. GI tract – acidity of gastric secretions prevents bacterial retention, giving antacids could allow bacteria to thrive, rapid peristalsis of small intestine prevents bacteria from staying in gut too long, delayed motility could damage this defense mechanism g. Vagina – low pH at puberty inhibit many microbes, antibiotics and oral contraceptives disrupt normal flora and can change pH 5. Recognize factors affecting the risk of infection. a. Infants and toddlers have lower defenses, only born with antibodies from mothers, breast fed babies have greater immunity because antibodies are in breast milk b. Young or middle adult have refined defense system, viruses are most causes of communicable disease, vaccinations are really improving communicable disease rates c. Older adults have changing body systems and decline in structure and function allow easier pathogen invasion, hospitalizations also put them at greater risk d. Nutritional status, stress, poor nutrition, big gun abx use, and diseases can all impact the rate of infection susceptibility 6. Identify factors that reduce the incidence of nosocomial infections. a. Risk factors for HAI’s -- # of care providers in contact with patient, # of invasive procedures, therapy received, length of hospitalization, cleanliness b. Urinary – unsterile catheter, improper drainage tubing position, open drainage system, catheter tube disconnected, drain port touching contaminated surface, improper specimen collection, obstruction of urinary drainage, urine reflux from tube to bladder, repeated catheter irrigations c. Surgical or traumatic wounds – improper skin prep, aseptic technique failure d. Bloodstream—contaminated IV tubing, insertion of additives to IV fluid, addition of connecting tubes or stopcocks to IV, improper care of needle insertion, contaminated needles, failure to change IV access when inflammation appears, improper technique 7. List factors to be assessed on patients with an infection. a. Review of systems b. Travel history c. d. e. f. Immunization and vaccination history Risk factor assessment: co-morbidities, therapies, medications, lifestyle risks, etc. Clinical appearance: s/s of infections Lab data with signs of infection 8. Recognize the significance of diagnostic tests which are indicative of an infection. a. WBC – normal 5-10 thousand– can increase during infection or decrease in viral or overwhelming infections b. Erythrocyte sedimentation rate – 15-20 mm/hr. – elevated in inflammation response c. Iron level – 60-90 – decreases in chronic infections d. Cultures – normal is sterile with no microbe growth e. Cultures and gram stain of wound, sputum, and throat – normal is no WBC on gram stain with possible normal flora f. Neutrophils – normal 55-70%, increased in suppurative (pus-forming) infection and decreased in overwhelming bacterial infection in older adults g. Lymphocytes – normal is 20-40% -- increases in chronic bacterial and viral infections, decreases in sepsis h. Monocytes – normal is 5-10% -- increased in protozoans, rickets, and TB i. Eosinophils – normal is 1-4% -- increased in parasitic infections j. Basophils – normal 0.5-1%, normal occurrence during infections 9. Describe recommended techniques for medical and surgical asepsis. a. Medical asepsis – reducing the number of organisms present and preventing the transfer of organisms, aka clean technique b. Surgical asepsis – prevents contamination by isolating the operative area from the unsterile environment, aka sterile technique, only sterile objects on a sterile field, sterile isn’t considered sterile if you can’t see it or it is below your waist, things aren’t sterile if it comes in contact with anything wet (strikethrough), fluid flows with gravity, the edges of a sterile field aren’t sterile i. Date and time bottles, only good for 24 hours, lipping the bottle to remove crystals, set all caps facing up ii. Put goggles and face shields on first, remove gloves first when PPE off 10. Identify protocols for isolation. a. Airborne – contaminates the air over long distances, needs a private room with negative airflow and door closed, hospital approved respirator required for entry, mask patient when transporting out of rooms for emergencies only, used in TB, small pox b. Droplet – contaminates the air over a 3 foot range, needs private room, surgical mask required if caring for pt within 3 ft zone, limit transportation and use surgical mask outside the room, used for Flu, Diphtheria, Woophing Cough, Pertussis, Mumps, and community acquired pneumonia c. Contact – contaminates skin to skin and physical contacted surfaces, private room with open door, gloves at all times, wash hands after removing gloves, wear gowns for close contact, limit transport out of room, Used in patients with MRSA, scabies, shingles, and herpes i. Extended contact- used in patients with C Diff must use soap and water before and after contact with pt, hand gels do not stop C. diff, use bleach for cleaning d. Protective – used when we need to protect pts from us, positive airflow room, no fresh or dried flowers, no plants, no fresh foods, for oncology neutropenic pts 11. Describe the body’s general immune response and the stages of the immune system response. a. Body’s own cells are covered with antigens that allow it to recognize self from foreign b. Swelling, redness, and warmth come from blood and nutrients rushing to site of invasion, aka a localized infection c. Overwhelming immune response can lead to anaphylaxis where HR increases, BP decreases, shock and unconsciousness result d. Stages: Defense, Homeostasis, and Surveillance 12. Describe how the nurse can manage the care of the patient with an infection, including the use of community resources. a. Assessment – determine how patient feels about illness or risk for infection, assess their knowledge base of infection transmission, review of systems, travel history, immunization and vaccination history, medical history, analysis of lab findings, b. Don’t forget to assess for psychological and social problems with infections, especially aids, tb, or std’s, isolation and relationship rejection need to be addressed, ask about their expectation of care and how involved they want to be in planning, encourage communications 13. Systemic inflammatory response syndrome – SIRS - the body’s response to sepsis, shock, or MI a. Scored on a chart for a sepsis protocol i. Respirations >20 ii. WBC <4 OR >12 iii. Temperature 100.4+ iv. HR >90 v. Left shift of WBC’s – shows increased number of bands (immature WBC) 14. Septic Shock – presence of sepsis with hypotension despite adequate fluid resuscitation, inadequate tissue perfusion resulting in tissue hypoxia, the normal immune response is exaggerated causing inflammation and coagulation to increase while decreasing fibrinolysis. Endotoxins from the microbe’s cell wall release cytokines to activate platelet activating factor which results in micro thrombi and obstruction of microvasculature. a. Three major pathophysiologic effects: vasodilation, maldistribution of blood flow, myocardial depression i. Respiratory failure can also occur. Initially hyperventilation as a compensation resulting in respiratory alkalosis, once compensation fails respiratory acidosis occurs. 85% of patients with sepsis develop respiratory failure. Most need placed on a vent. b. Caused by an infection like pneumonia, peritonitis, UTI, invasive procedures, indwelling lines and catheters c. At risk populations are – older adults, pts with chronic diseases like DM, renal disease, or heart failure, pts with immunosuppressive therapy, malnourished pts, or debilitated pts, skin or mucous membrane damage, presence of foreign body, resistant abx therapy, pulmonary or cardiovascular disease, invasive procedures 15. Stages of Septic Shock a. Compensatory stage -- Not usually clinically apparent, metabolism changes from aerobic to anaerobic, lactic acid builds up, O2 begins to become unavailable, during this stage the body attempts to compensate for loss of tissue perfusion, trying to shunt blood to maintain vital organs, can have full recovery from this stage with no long term effects i. Hyperventilation causing respiratory alkalosis, release of chemicals internally, vasoconstriction to briefly bump blood pressure then a rapid decrease in BP, cardiac output, and narrowed pulse pressure ii. AIRWAY BREATHING CIRCULATION iii. Stabilize c-spine with collar iv. Give high flow O2 with 100% NRB mask or bag valve mask v. Call respiratory, may need vent or suctioning vi. 14-16 gauge IV and/or central line vii. Give fluids – NS or Lactated Ringers at 30mL/Kg viii. Labs – cultures and WBC ix. Give abx and adjust when cultures return x. Give vasopressins because nor-epi helps reconcile tissue perfusion xi. Give IV corticosterioids to maintain BP xii. Control any bleeding xiii. Place catheter and NG tube, keep gut moving with continuous feeds of 10ml/hr xiv. Get 12 lead ECG and watch for arrhythmias bc they could throw clots xv. Monitor closely for decreased LOC, check vitals and periperhal pulses, skin color, temperature, and urine output, monitor H&H, check glucose and keep under 180 xvi. Monitor respiratory status 15-30 minutes xvii. Turn these patients and do ROM exercises, q 2 hours if possible b. Progressive stage—compensatory mechanisms start failing, aggressive treatment is given to prevent multisystem organ dysfunction syndrome (MODS) i. Edema from fluid shunting from blood to body ii. Lungs fill with fluid, rales crackles and hypercapnia iii. Decreased cardiac output, BP, and blood flow to periphery iv. Decreased LOC and jaundice because of high ammonia levels due to liver failure v. Ulcer formation and GI bleeds with blood possible in NG tube suction vi. Acute renal failure with decreased urine output vii. Low platelet counts causing thin blood and bleeding from eyes, IV sites, etc. c. Refractory/irreversible stage – decreased perfusion because of continued vasoconstriction i. Lactic acid buildup ii. Worsening hypotension and tachycardia with weak and thread pulse iii. Decreased coronary blood flow leading to cerebral ischemia and possible coma iv. All organs failing with urine output less than 30ml/hr v. Clammy pale skin with low core body temperature , central cyanosis vi. Unlikely recovery from this stage 16. Bioterrorism Small Pox Signs and symptoms Fever, malaise, body aches, vomiting, rash starting on face and spreading downward within 24 hours Transmissions Through prolonged face to face contact or direct contact with contaminated objects, contagious from start of fever until last scab falls off Airborne and contact precautions Live vaccination stopped in 1980 Treatments Pneumonic Plague Fever, headache, weakness, pneumonia, dyspnea, chest pain, cough, hemoptysis, watery sputum Y. pestis infects the lungs, spread through the air Droplet and standard precautions Abx within 24 hours of symptoms, give gentamicin, tetracycline, or streptomycin Anthrax Botulism Small blisters on skin with black centers, nausea, loss of appetite, bloody diarrhea, fever, abdominal pain, if inhaled cold or flu like symptoms Handling infective products from infective animals, breathing spores, eating infected animal meat that is infected Drooping eyelids, blurred vision, slurred speech, dysphagia, muscle weakness decending through body causing paralysis however far down it spreads Food born through ingesting Clostridium Botulinum Standard precautions Treat with antibiotics like Cipro, doxycycline, or PCN Vaccine in the works Standard precautions Treat with anti toxin held by CDC which is effective in reducing severity of symptoms if given early enough 17. Antibiotic resistance – the ability of an microbe previously sensitive to an antibiotic to withstand the effects of the drug either over time or suddenly a. Education – don’t take preventative abx, wash hands frequently, follow directions, finish full course, not for anything except bacterial infection, don’t medicate with leftovers b. MRSA – methicillin resistant S. Aureus, treated with Bactrim, vancomycin, or bactroban c. VRE – vancomycin resistant enterococci, treated with zyvox d. VISA – vancomycin intermediate resistant S. Aureus, treated with zyvox e. VRSA – vancomycin resistant S. Aureus, must contact CDC who may direct course of treatment, treat with zyvox, not really in our area yet 18. Allergic disorders – collect allergies during health history, avoid allergens, wear med alert bracelet, carry epi-pen a. Diagnostic tests – CBC where you will see eosinophils and lymphocytes go up, skin test will show a raised ‘wheel’ indicating true allergy b. Drugs a. Antihistamines – stop allergy symptoms by blocking histamines b. Decongestants – reduce swelling and congestion c. Epinephrine – BEST treatment for anaphylaxis, given sub q d. Corticosteroids – short term use, decrease inflammation White Blood Cells Erythrocyte sedimentation rate Iron Cultures Cultures and gram stain Neutrophils Normal 5,000-10,000 15-20mm/hr Decreases in chronic infections Indicates no microbe growth Indicates no sign of infection, possible to see normal flora 55-70% Increased in suppurative (pus-forming) infections and decreased in overwhelming bacterial infections in older adults Lymphocytes 20-40% Increases in chronic bacterial and viral infections Monocytes 5-10% Increased in protozoan infections and TB Eosinophils 1-4% Increased in parasitic infections Basophils 0.5-1% Normal occurance during infections e. Antipruretic – reduces itching c. Anaphylaxis – serious and life threatening exaggerated reaction where angioedema occurs with HR increases, BP decreases, shock and unconsciousness result d. Latex allergy – can be local or systemic, food allergies can increase risk Banana, kiwi, peach, grape, apricot, Avocado, Chestnut, water chestnut, hazelnut, Tomato, Guava, a. 60-90 Sterile No WBC Causes Increases during infection or decreases during viral or overwhelming infection Elevated in inflammation response ANTIBIOTICS 1. PENICILLIN (PCN) – ex: Amoxicillin (augmentin), Methicillin effective against a broad variety of bacteria by weakening bacterial cell wall Especially used for strep pneumonia or meningitis or strep viridans which causes endocarditis Most common drug allergy, if giving dose must eval for 20-30 min to determine if allergic reaction will present Take with full glass of water (no citrus juice) on an empty stomach ** Penicillin V, Amoxicillin and Augmentin can be taken with food 2. MACROLIDE – ex: Erythromycin, azithromycin (zithromax) Used in legionnaire’s, pertussis, diphtheria Inhibits metabolism of antihistamines and blood thinners, monitor for toxicity causes GI disturbance, IV irritation, Reduces activation of med if given with fruit juices or acid foods, Liver function tests are needed (remember: macrolide girl) Commonly used for PCN allergy Take with full glass of water and food to reduce GI upset (no citrus or acid) 3. CEPHALOSPORIN: Cephalexin (Keflex) and Cephradine (anspor, velosef) Used in UTI, post op infections, pelvic infections, and meningitis Causes GI disturbance, Increase in glucose, Anaphylaxis and alcohol may cause vomiting, Nephrotoxicity, Thrombocytopenia (remember: Cef the Giant) NOT for those with pcn allergy, typically used if z-pack fails Take with a full glass of water on an empty stomach unless GI upset then can be taken with food 4. TETRACYCLINE: doxycycline (vibramycin) and tetracycline hydrochloride (sumycin) Used in acne vulgaris, lyme disease, anthrax, and h. pylori Causes Sunlight sensitivity, Take with full glass of water, O avoid antacids, iron and milk, Put drug on empty stomach (remember: STOP cyclines) NOT for pregnant women or children under 8 years because it will stain teeth THROW AWAY after expired or it can cause severe kidney damage 5. AMINOGLYCOSIDES: gentamicin, tobramycin sulfate (nebcin), neomycin Used in e.coli, klebsiella pneumonia, and tape worms one can’t hear, one can’t pee, one can’t feel, they’re the three toxic amino mice Can cause ototoxicity, nephrotoxicity, neurologic disorders MONITOR PEAK AND TROUGH 6. FLUOROQUINOLONES: Ciprofloxacin (Cipro), Ofloxacin (floxin), Levofloxacin (levaquin) Used in urinary, respiratory, GI, bone/joint, skin and soft tissue infections Can cause tingling, dizziness, weakness, and psychosis, chest pain, tachycardia, and SOB NOT for under 18 because it can cause tendon rupture and joint swelling 7. SULFA: trimethoprima sulfamethathiazole (TMP-SMZ, Bactrim), Co-trimaxozole (Septra) Used in UTI, Otitis media, bronchitis Causes Sunlight sensitivity, Unesirable rash and renal toxicity, Look for urine output, fever, sore throat, and bleeding, Fluids galore, Anorexia and anemia (remember: SULFA) NOT for those with steven Johnson syndrome, anemia, crystal-uria (need 2-3L fluid/day) or pregnant women, Dilantin pts, diuretic patients, or blood thinner patients Take with a full glass of water on an empty stomach 8. VANCOMYCIN: Vancomycin (vancocin), Azeteonan (azactam) used in serious infections like MRSA, and C. diff Can cause ototoxicity, infusion reaction, thrombophlebitis NOT for renal failure pts MONITOR PEAK AND TROUGH ANTIFUNGALS – many drug interactions, observe hygiene, liver functions, take with food 1. ANTIFUNGALS: Miconazole (monistat), Clotrimazole (lotramin), fluconazole (difulcan) nystatin (mycostatin) Used in candidiasis, ringworm, yeast, athletes foot, and thrush Can cause itching and rash NOT for pregnant women because it depletes folic acid and causes neural tube defects Take with food and small frequent meals to decrease GI upset, no antacids or med won’t work 2. AMPHOTERICIN Used in systemic fungal infections and histoplasmosis Can cause heart irregularities, nephrotoxicity, hypokalemia, and thrombocytopenia (remember: amphoTERRIBLE) 1. ANTIVIRALS: Acyclovir (zovirax), valacyclovir (Valtrex), and osltamivir (Tamiflu) Used in herpes simplex 1 &2, and influenza Can cause Nephrotoxicity and thrombocytopenia