vaccines (malaria, travel etc) Flashcards

(123 cards)

1
Q

memory from adaptive immunity

A

Proliferation of 1st immune response (T and B cells)
Some into memory T. B cells

Shorter lag time when exposed to antigen A again
Activate memory T, B cells

HEIGHTENED STATE of reactivity
Shorter and stronger reaction
More/ higher
Better immunity

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2
Q

Live attenuated eg

A
  • MMR
  • Rotavirus
  • Smallpox
  • Chickenpox (varicella)
  • Yellow fever
    BCG
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3
Q

inactivated vac eg

A

Polio, hepA (food, water), rabies, flu (influenza)

jap encephalitis, influenza, tick-borne encephalitis

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4
Q

Subunit, conjugated vacc, eg

A

Hep B, pertussis, pneumococcus, HIB, influenza

typhoid (polysacc)
meningococcal

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5
Q

toxoid vacc eg

A

Diphtheria, tetanus

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6
Q

recombinant vacc eg

A

Hep B

HPV

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7
Q

live attenuated vaccine is _

A

○ Weakened virus after passing it through tissue culture multiple times
Replicates in body to stimulate a response

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8
Q

pros of live attenuated vacc

A

§ Activates killer T cells
§ 1,2 dose can provide lifelong immunity. Robust cell-mediated immunity
Like natural infection – stronger reaction

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9
Q

cons of live attenuated vacc

A

§ must be refrigerated.
§ Not suited for immunocompromised grps
□ Uncontrolled replication of virus
Clinical manifestation of disease

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10
Q

inactivated vacc is from _

A

Pathogen treated with heat or chemicals (killed)

Before introduction into body

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11
Q

inactivated vac pros

A
  • Easy to store, transport
    Low risk of causing infection
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12
Q

inactivated vac cons

A
  • Elicit weaker immune response
    • Booster
      *Several doses
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13
Q

Subunit
(Protein, polysacc, conjugated) vacc is __

A

One or more parts of pathogen (protein, polypeptide) isolated

Used to evoke immune response (weak)

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14
Q

subunit vacc pros

A
  • Low risk of adverse reaction
    Used in immune weakened systems
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15
Q

subunit vacc cons

A
  • Difficult to manufacture
    May need boosters
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16
Q

toxoid vacc is made from __

A

Toxins produced by pathogens instead of pathogen itself

Deactivated and used to produce immune response
- formaldehyde, temp, duration

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17
Q

toxoid vacc pros

A
  • Unable to cause disease or to spread
    Stable, easy to distribute, maintain immunity
  • anti-toxoid Ab produced, neutralise toxic effect
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18
Q

toxoid vacc cons

A

May need boosters to maintain immunity

or adjuvant

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19
Q

viral vector vacc

A
  • Vector virus contains DNA spike protein
    • Large
    • Highly glycosylated transmem (of virus)
      Vector virus are genetic makeup of diff viruses/ engineered viruses
  • harmless, modified version of virus
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20
Q

recombinant vacc is made from

A

Vaccine produced by genetic engineering

May contain
* No actual virus (hep B, HPV)
* Modified strain of virus
- Live oral typhoid

recombinant: contain genes to encode specific antigen

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21
Q

precautions of live vaccine

A

○ Avoid in preg
§ Theoretical fetal infection
§ Live vaccines delayed until after delivery

○ Infancy <1 yr old
○ Severely immunocompromised pts
§ Hematologic, solid organs malignancies
§ Immunosuppressive meds, chemotherapy
§ HIV with CD4 < 200
- Small chance of uncontrolled replication – full-blown infection

○ Spaced 3-10 mnths apart from admin of Ab containing pdts
§ Ig, blood transfusion
§Circulating Ab may reduce the effectiveness of triggering an immune response

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22
Q

live vacc taken tgt

A

○ Another live vaccine SAME DAY/ within 28days

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23
Q

herd immunity

A

○ Enough pop immunised to:
§ Contain spread
§ Protect community

				-Elderly, children, immunocompromised to qualify for vaccine
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24
Q

percentage for herd immunity

A

○ Percentage depends on how contagions disease is
§ Highly contagious = higher percentage needed

(measles high contagious: 83-84%)
- protect immunocompromised

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25
primary dose
Single dose/ few doses (series) Induce adequate immunity
26
booster dose
Ab conc wanes over time Booster dose (additional dose) required to maintain protective lvl of Ab
27
childhood immunisations 12 vacc protects against 14 disease 3 are live
1) BCG 2) Hep B 3,4) dTAP & Tdap 5) IPV (polio) 6) Haemophilus influenzae type B 7) Pneumococcal conjugate (PCV10, 13) 8?) pneumococcal polysacc (PPSV23) 9) MMR 10) varicella 11) human papillomavirus 2/4 12) influenza
28
adult vacc schedule Protects against 11 diseases - means recc for adults that had not been vaccinated with these previously
1) influenza 2) pneumococcal conjugate PCV13 3) pneumococcal polysacc PPSV23 4) Tdap 5) HPV2/ 4 - 6) hep B - 7) MMR - 8) varicella -
29
effectiveness of vacc
1) Varies by vaccine 2) Other factors also affects □ Site vaccine given - Hep A/B at IM (deltoid) ---- not gluteus □ Pt age, immune status -Less effective in older pts □ Cold chain problems - Recommended temp affects stability -- quality of vaccine
30
Adverse effects (AE) of vacc
Mild, common: □ Pain, redness, swelling at inj site □ Headache □ Myalgia Uncommon □ Fever, hematoma Severe, rare: □ Anaphylaxis, hypersensitivity (systemic)
31
risk of not giving vacc
□ Not giving pt a vaccine is also a risk □ Exposes pt to disease, risk of mortality, morbidity and complications
32
CI, precaution of vaccine Not to get vaccine at this time vs forever
□ Allergy to vaccine/ components -Need look for substitutes □ mod/ severe illness (>38*C) □ Bleeding risk (pt on anti-coagulant, low PLT count) - IM inj, bleeding in muscle risks □ Pregnancy (No live) □ Immunocompromised (No live)
33
Moderate/ severe illness (>38*C) precaution for vacc
No evidence to suggest that concurrent sickness will affect vaccine safety/ efficacy ◊ If pt is unwell, should defer until well to take vaccine ◊reduce any new symptoms for pt ◊ Delay vacc until recovered from acute illness
34
Simultaneous administration
§ Most vaccine administered simultaneously/ within same day □ Without reducing efficacy/ incr AE □ Prevent missed doses (adherence) § Live vaccine admin IM, SC spaced 28days apart □ Reduce risk of Ab elicited from first vaccine to interfere with Ab of 2nd LIVE vaccine
35
no simultaneous for which 2 vaccs? vacc for
PCV, meningococcal conjugate vaccine in pt with functional or anatomical asplenia (no spleen) □ 4 wk interval b. admin of 2 vaccines -Avoid interference of meningococcal conjugate vaccine (with PCV)
36
missed dose
□ Dose given asap, continue course as if not interrupted □no additional dose required
37
Resources to provide advice on preventing infections in travelers
○ Specific advice for travel destination § Routine vaccines before traveling § Recommended vaccination/ prophylaxis for certain countries (outbreak, endemic) □ Yellow fever, malaria
38
medical considerations before int. travel
Pretravel consults: Preventive and educational interventions § 4-6 weeks before departure § Vaccines, prophylaxis takes time (gain suff conc// see ADR) individual risk factor vary greatly post travel advice
39
Indiv risk factors -- risk assessment
* Medical history * Medication * Disabilities * Allergies * Immune status * Immunizations * Pregnancy * Lactation * Prior travel experience * Specific itinerary * Region (urban, rural) * Season * dates * Activities * Adventure travel, events * More prone to food borne? * How exposed to risk factors * Type of accommodations * Traveler's risk tolerance * CI to vaccine * Financial challenges * Expensive * Time frame *Freq of admin
40
Standard in-office interventions
1) admin of immunisation (update routune vacc: MMR, Tdap, pneumococcal, varicella, influenza) 2) routine travel vacc (hep A, typhoid, hep B) 3) special travel vacc (yellow fever, rabies, polio, meningococcal) 4) malaria chemoprophylaxis 5) traveler's diarrhea (ORS, AB)
41
Focused education before trip
1) vector-borne disease 2) others (altitude, thrombosis, bloodborne, motor vehicle, resp, rabies) 3) medical kits
42
risk assessment for pretravel consult checklist
PMH special considerations immunisation hist prior travel exp itinerary timing (duration, season, departure) reason for travel travel style (adventurous, food) special activities
43
Post-travel advice
§ Continuous prophylaxis (malaria) § Self-assessment of any abnormal symptoms § Post travel incubation (as symptoms may take time to arise) § Visit doc, must remind to mention travel visit
44
* Travel vaccines available for common infections IMPORTANCE
○ Many travelers develop infections during travel § Avoided through proper vaccination § Risk avoidance ○ Travelers serve as conduits -- spread disease across the globe § Covid, AB resistance ○ Less developed countries - higher rates of infection: § Saharan Africa, Southern Asia, Central, South America, Caribbean
45
Major routes:
§ Food, water borne: fecal-oral transmission (hand hygiene/ flies) § Insect vector borne § Transcutaneous (skin-skin) § Respiratory § Blood, body fluids (sexual/ contaminated needles)
46
Travel vaccines, routine vaccines updated recommended some are compulsory in some countries:
routine: age app vacc Meningococcus, poliomyelitis, yellow fever
47
resp (airborne, droplets)
influenza pneumococcus meningococcus diphtheria, pertusis hemophilus influenzae MMR chicken pox BCG - TB
48
food and water transmission
hep A typhoid cholera poliomyelitis
49
vector borne
yellow fever jap encephalitis
50
blood, body fluids (sexual contact)
hep B HPV
51
transcutaneous spread (bites, cuts)
tetanus rabies
52
Travel vaccines considerations
1) Type of vaccine 2) Difference in administration 3) Given tgt? 4) Effectiveness? 5) Booster needed? Up to date with vaccination status?
53
choice of travel vaccines
§ Risk assessment of exposure to VPD (vaccine-preventable diseases) □ Chosen itinerary, severity of disease if acquired □ Any risk presented by vaccine § Risk of infection varies within country -- itinerary needed □ Travel style □ Type of accommodation □ Food □ Activities § Consult travel health resources for specific recommendations
54
last minute travel (consideration)
§ Vaccine take 2 wks to elicit some protective response § Urgent travel/ inadequate time: □ Accelerated immunisation schedules - Single dose - Shorter immunisation interval between doses □ Risk avoidance □ Drug prophylaxis if applicable □Referrals to health services at their destination (equipped with tets materials/ treatment)
55
5 species of plasmodium:
P. Falciparum ○ Most prevalent ○ Most dangerous, highest rate of complications and mortality ○ Resistant to: mefloquine, Chloroquine P. Malariae P. Ovale P. Vivax ○ Most prevalent Knowlesi
56
malaria Clinical features
* Fever, chills, sweats, headaches, body aches, weakness, NV, cough, diarrhea, abdominal pain * Progress to organ failure, sepsis, death (without timely treatment) May develop symptoms even with prophylaxis
57
Epidemiology Malaria endemic countries
* Widespread, transmitted in tropical, subtropical areas (EQUATOR) * Causes 400,000 death: mostly in children * Lack immunity * If survive, will be more immune as an adult * Mostly transmitted in: * Africa, south of Sahara * Oceania, Papua New Guinea
58
Transmission malaria
* Through bites of INFECTED female Anopheles mosquitoes *Transfusion of contaminated blood products, organ transplantation [RBC PHASE], vertical transmission (mother --> fetus)
59
risk of transmission incr/ decr factors
* Incr risk: ○ Between dusk and dawn ○ End/ soon after rainy season * Decr risk: ○ During colder season/ region ○ In deserts ○High altitudes ○Large urban areas (EXCEPT India, Africa)
60
malaria lifecycle 2 hosts, 1 parasites
1) HUMAN LIVER (EXO-ERYTHROCYTIC CYCLE) * Grow and multiple in liver cells P. Vivax, P. ovale ○ possible dormancy: 4wks --- 1yr 2) HUMAN BLOOD (ERYTHROCYTIC CYCLE) * Treatment only in blood phase, need wait after liver phase * Grow and multiple in RBC * Differentiation into sexual stages (gametocytes) * Clinical symptoms 3) MOSQUITO: SPOROGENIC CYCLE * Mate, growth, multiple, release *Another blood meal to transmit disease
61
Strategies for prevention ABCDE
1) Awareness of risk * Possibility of delayed onset (4wks dormancy) * main symptoms in blood phase 2) bite prevention * Stay away from mosquitoes * Especially between dusk - dwan * Chemical, physical repellents 3) Chemoprophylaxis * Adhere closely to antimalarial preventive medications when prescribed 4) Diagnosis * Early recognition and seek treatment * Require institute to have proper equip: ○ Blood smear to check for plasmodium in RBC 5) Environments * Keep off mosquito breeding places ○ Swap, marshy areas ○ Esp in late evenings, at night
62
chemoprophylaxis
* ATOVAQUONE + PREOGUANIL (Malarone) * CHLOROQUINE * DOXYCYCLINE * MEFLOQUINE
63
Considerations for choosing antimalarial chemoprophylaxi
1) Travel itinerary a. Specific malaria species b. drug resistance (mefloquine & chloroquine) i. CDC, WHO: recommendation for prevention by country 2) Traveler's medical history a. CI: preg, G6PD def, allergy, comorbidities b. DDI 3) Traveler's preferences that may affect adherence a. Regimen taken daily vs weekly (same day) -- adherence b. Cost consideration ($10 vs $0.10 per tab/cap) 4) Travel departure date and duration a. Regimen may need to be started 2 weeks advance/ b. Same 1-2 days before i. Build up suff conc See if traveler got ADR
64
Risk and type of prevention for malaria types
* TYPE A - v limited risk of malaria * Mosq bite prevention * TYPE B - risk of non-falciparum malaria * Mosq bite prevention * + chemoprophylaxis ○ chloroquine/ doxycycline/ atovaquone-proguanil/ mefloquine § Select based on parasite sensitivity (efficacy against) § Side effects § CI * TYPE C -- risk of P.Falciparum malaria * Mosq bite prevention * + chemoprophylaxis ○ doxycycline/ atovaquone-proguanil/ mefloquine § Select based on drug resistance pattern □ NO chloroquine = RESISTANT § Side effects CI
65
ATOVAQUONE + PREOGUANIL (Malarone) dose
1 adult tablet daily With food or milky drinks (Better absorption, less SE) 1 tab: 250mg ATOVAQUONE + 100mg PREOGUANIL POM w/ exemption Pharmacy can prescribe and dispense (based on pt pop, indication, duration)
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ATOVAQUONE regimen
Start 1-2 days prior trip Daily during trip Continue 7 days after return Suff days to push out from liver phase
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CI for atovaquone
Hypersensitivity Renal impairment CrCl <30ml/min preg child < 5kg
68
ADR for atovaquone
NV Stomach pain Diarrhea Headache dizziness
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DDI for atovaquone
Rifampicin Metoclopramide Efavirenz
70
Special pop for atovaquone
AVOID: Pediatric strength tablet, dose for infants, child > 5kg Avoid preg, lact (<5kg baby)
71
ADV for atovaquone
* Last min traveler (1-2 days) * Daily meds * Shorter trips, take 7 days after return * Well tolerated (SE uncommon) *Pediatric tabs avail, more convenient
72
DISADV for atovaquone
* Cannot be used by preg/ breastfeed child <5kg * Not for severe renal impairment * More expensive * 1 TAB = $10!!!!! * Esp for long trips (daily) *Some dw take everyday (children)
73
CHLOROQUINE dose
2 tab (total 500mg salt) weekly (with/ after meals) 1 tab = 250mg chloroquine base Pharm only
74
CHLOROQUINE regimen
Start 1-2 wks before departure Same day every week during trip Continue for 4 weeks after trip
75
chloroquine CI
- Hypersensitivity - Chloroquine resistance common in some regions Precaution: * Exacerbate psoriasis * Seizure disorders * Myasthenia gravis * Auditory damage * Liver impair -Maybe G6PD def (but some can?)
76
chloroquine ADR
NV Stomach pain Skin rsh/ itch
77
chloroquine DDI
QT-prolonging strong CYP3A4i Clarithromycin, voriconazole
78
chloroquine special pop ALLOWED
CAN: for children, preg, breastfeeding women
79
adv for chloroquine
* Some would rather take meds weekly * Good choice for long trip (wkly) * For those taking chronically for rheumatologic conditions * No need additional meds * For preg (all trimesters)
80
disadv for chloroquine
* Not for Chloroquine resistance !! * Exacerbate psoriasis * Some dw take weekly * Not for short trips * Continue for 4wks after * Not for last-min * Need 1-2 weeks before * have suff conc build up
81
DOXYCYCLINE dose
100mg daily With or after meals Swallow cap with FULL GLASS OF WATER, upright for at least 30mins prescription only
82
doxycycline regimen
1-2 days prior to trip Daily during trip Continue for 4wks after trip
83
doxycycline CI
- Hypersensitivity - Not for children <8yrs (dentitiion) - Preg - Breastfeeding Precaution: * GI discomfort ○ Oesophagitis ○ Gastritis * Photosensitivity
84
doxycycline ADR
NV GI discomfort Sunburn Vaginal candidiasis
85
doxycycline DDI
Reduce bioavil if take with * Multi-valent ions * Adsorption (will decr absorption of drug) Space apart (2hr before, 6hr after)
86
ADV for doxy
* Some prefer take daily medicine * Last min travelers * 1-2 days prior * Least expensive * $0.10 per tab * Some alr taking for ACNE * No need additional meds * Prevent other additional infections * Rickettsia * Leptospirosis *Those doing hike, camp, wading, swim fresh water
87
disadv for doxy
* NOT for preg women, child <8yrs * Some dw take everyday * For short trips, dw take 4 wks after * Vaginal yeast infections when taking AB * Can avoid but maybe some dw SE: * Upset stomach -- water * Sun sensitivity -- sunblock
88
mefloquine dose
250mg weekly After meals pharmacy only
89
mefloquine regimen
1 week before (prefer 2-3 wks check ADR) Weekly during trip Continue 4wks after return
90
mefloquine CI
* Hypersensitivity * Region mefloquine resistance common in some regions * Hist of psychiatric * Depression, ANX, psychosis, schizophrenia * Convulsion disorders * Cardiac conduction abnormalities
91
mefloquine ADR
GI discomfort Dizzy Fatigue Headache Insomnia Vivid dreams Neuropsychiatric disorder (monitor in the 2-3wks before fly)
92
DDI for mefloquine
ketoconazole
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special pop allowed for mefloquine
CAN: for children > 5kg, preg, breastfeeding wome
94
adv for mefloquine
* Prefer take med wkly * Good for long trips (once wkly) * Used in preg
95
disadv for mefloquine
* Not in areas with mefloquine resistance * Psychiatric conditions pt * Seizure disorders pt * Cardiac abnormalities pt * Not for last min * 2wks advance * Dw take wkly meds * Not for short duration (continue 4wks after)
96
Protection against insect bites
1) barrier protection 2) insect repellent 3) advice
97
barrier
* Avoid expose in dusk - dawn [NIGHT BITERS] ○ Stay indoors * Clothes, expose less skin, not thin clothes * Light colour * Sleep under permethrin-impregnated bed net Sealed, air-con room// screened windows with fan
98
Insect repellent
* Efficacy and duration vary from pdts * Factors affect: ○ temp, lvl of activity, perspiration, water exposure, abrasive removal HIGHER CONC = LONGER DURATION 1) DEET (20-50%, 6-12hr protection) 2) PICARIDIN (>20%) 3) OIL, LEMON EUCALYPTUS 4) IR3535 5) 2-UNDECANONE (methyl nonyl ketone)
99
Precaution when using repellent
○ Only to exposed skin/ clothes (not skin under clothes) ○ Not on cuts, wounds, irritated skin ○ Not on face directly (hand then face) § Not on eyes, mouth, some on ears □ Wash hands after (avoid eyes, ingestion) § Put on hands then apply on children tin layer □ Wash, bathe after return from outdoors ○Apply enough + reapply
100
advice for protections
* Interventions are EFFECTIVE =/= 100% * Symptoms occur 4wks-1yr = immediate medical attention * Serious, may be deadly illness ○ Traveler have flu-like/ fever after going malaria-risk area § Seek medical attention, inform of travel hist * Should travel with full treatment course, if cannot get medical care there (mission trip) *Exclusion from blood donation (4mnths after return)
101
Surgical site infections (SSI)
○ Infections occurring within 30 days after surgical operation/ ○ Infections occurring 1yr if implant left in place § Affect incision or deep tissue at operation site
102
Surgical site infections (SSI) caused by
= healthcare-associated infection § May be superficial or deep incisional infections Infection involving organs/ body spaces
103
surgical AB prophylaxis:
○ Administration of AB prior to CLEAN// CLEAN-CONTAMINATED surgeries Prevent post-operative surgical site infections (SSI)
104
Risk factors for SSIs:
1) pt (immunity related) 2) operational related
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pt risk factors
1. Age (young, old) 2. Smoking 3. Coexistent infections at remote body site 4. Colonisation (MRSA) a. Drug resistant strains 5. Recent surgical procedure a. Havent recover from prvious 6. Underlying illness 7. Obesity >20%IBW 8. Nutritional status (malnourish) 9. DM uncontrolled 10. Length of pre-operative stay a. HAI colonised on surface etc 11. Altered immune response a.Immunosuppressant therapy
106
Operational related
1. Duration of surgical scrub 2. Skin antisepsis 3. Pre-op (clear pathogens from pt) a. Pre-op shaving b. Pre-op skin prep 4. Duration of surgery 5. Antimicrobial prophylaxis a. Agent, dose, time of admin, duration 6. Operating room ventilation 7. Inadequate sterilisation of instruments a. contamination 8. Biofilms a. Foreign material in surgical site b. Surgical drains 9. Surgical/ surgeon's technique a. Complicated may allow bact to hide and proliferate
107
Characteristics of optimal SAP:
a. Optimal SAP (highly effective in preventing SSI) b. Ideal prophylactic AB regimen 1) Effective against pathogens (mostly likely to contaminate the surgical site -- skin flora) 2) Appropriate dose, time (achieve highest tissue conc upon skin incision) 3) Safe 4) Admin for SHORTEST effective period - minimise ADR - develop resistance (selective P) - costs
108
INDICATION FOR SAP:
1) clean - insertion of prosthesis/ artificial device 2) clean-contaminated surgery 3) contaminated (AB used as treatment)
109
CLEAN SURGERY
a) Where prosthesis/ implant inserted b) When SSI pose catastrophic risk - hip replacement, heart valve NOT recc for clean: healthy skin incised, mucosa of (resp, GIT, genitourinary, oropharyngeal cavity not TRANSVERSED)
110
CLEAN-CONTAMINATED SURGERY
resp, GIT, genitourinary trace penetrated under cotnrolled conditions not unusual contamination - laryng, appendict, cholescys, transurethral resection of prostate
111
Justified if for other surgeries if:
a) Pt underlying medical condition associated with incr risk of SSI b) Pt immunocompromised Malnourished, neutropenic, immunosuppressants
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CONTAMINATED (AB for treatment, not SAP)
macroscopic soiling of operative field - bowel resection, biliary/ genitourinary tract surgery with infected bile or urine
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considerations (systematic)
Choice of AB Timing of admin AB dose - Redose Duration Non-SAP strategies, prevent SSI - Operational risk factors
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Choice of AB
* Cover expected pathogen for operative site * No need COVER ALL, just main one * Cafezolin (1st gen) no cover enterococci, but still used cause gram -ve * Conc HIGH lvl at site (prior to incision) * Narrow-spectrum AB agents preferred (less selective P) * Local resistance pattern * Association of AB agents (MDR? CDAD? ) * MRSA colonisation * pt got ADR? (beta-lactams)
115
Association of AB agents
* 3rd gen cephalosporin, fluoroquinolones, clindamycin ○ Incr risk of C.difficile infection * Develop multi-drug resistant colonization/ infections should be taken into considerations
116
MRSA
* Screen for MRSA colonisation. ○ Decolonise accordingly, for pt undergoing high-risk surgeries ○ (cardiac, orthopedic, neurosurgery with implant) * Should be considered for pt with known MRSA colonisation or recent MRSA infection * Vancomycin < effective < cefazolin ○ For MRSA caused SSI ○ Can combine for prophylaxis in MRSA colonised pt
117
Pt with beta-lactam allergy
* Incr odds of SSI due to 2nd line SAP * Imperative to obtain detailed AB and allergy assessment: verify true allergy
118
SEVERE PENICILLIN ALLERGY
§ Anaphylaxis § Urticaria § Bronchospasm § Angioedema § SJS § TEN Not receive beta-lactam for surgical prophylaxis
119
Uncomplicated non-IgE mediated AR to penicillin
§ Maculopapular rash □ Cephalosporin (after discuss with pt and allergy team) □ Cefazolin (unique R1 side chin) - No side-chain cross-reactivity with other b-lactams
120
Timing of admin
* Start admin within 30-60min before surgical incision * Good conc at site * Infused completely before incision * Fluoroquinolones and vancomycin need longer infusion time Admin at least 1hr before incision
121
AB dose Redose
* Intra operative re-dosing required when * Duration of procedure > 2 half-life of drug * Excessive intra-op blood loss >1500mL Extensive burns
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Duration
* NOT EXCEED 24HR for most procedures * No benefit when given >24hrs * May associated harm ○ Incr risk of acute kidney injury ○ Clostridioides difficile infection ○ Incr selective P (MULTI-DRUG RESISTANT ORG)
123
eg for SAP
* For cardiothoracic, vascular surgery * Appendectomy * Gastroduodenal, esophageal * Small bowel