Infectious Flashcards
Penicillin is what type of an antibiotic?
Beta-lactam
What is the true penicillin allergy %, and cross-over % between penicillin and cephalosporins?
<1% true allergy
10% cross-over allergy between pcn and cephalosporins
What is it about cephalosporins that cause the crossover allergy with pcn?
they contain benzylpenicillin
How do beta-lactam atbx work?
inhibit the cross-linking of peptidoglycan [inhibit cell wall synthesis]
3-carbon, 1-nitrogen ring is highly reactive
What 5 types of antibiotics are beta-lactams?
- penicillins
- cephalosporins
- Carbapenems
- Monobactams
- Beta-lactamase inhibitors
What is the timeframe for SSI?
w/n 30d of surgery, or 1 year of prosthetic implant or organ
What are the 6 mechanisms of SSI prevention?
- Preop atbx (so concentration is established by INCISION)
- Glycemic control <200mg/dL
- Normothermia
- optimize oxygenation
- antimicrobial soap before surgery
- alcohol-based skin prep (antiseptic agent)
What is a catheter-associated BSI?
bacteremia or fungemia in pt with CVC and AT LEAST ONE positive blood culture obtained from a peripheral vein
Length of R subclavian CVC?
14cm
Length of R IJ CVC?
15cm
Length of L IJ CVC?
18cm
Length of L subclavian CVC?
17cm
Clostridium Difficicle
spore-forming bacterium
toxins A & B create diarrhea & pseudomembranous coliits
may need subtotal colectomy & ileostomy
What 2 antibiotics can cause Cdiff?
vancomycin
metronidazole
What is the mortality of necrotizing soft tissue infections?
up to 75%
5 infections included in necrotizing soft tissue infections
- gas gangrene
- toxic shock syndrome
- Fournier’s gangrene [genital/perineal area]
- severe cellulitis
- flesh-eating infection
Anesthesia management of necrotizing infections
- resuscitation d/t hemodynamic instability
- release of cytokines
- good IV/A-line/CVC
- blood product availability - do not delay surgical treatment
AT RISK OF MULTIORGAN FAILIURE → ICU
Tetanus neurotoxin & what does it do?
tetanospasmin;
suppresses inhibitory neurons in the spinal cord = generalized skeletal muscle contractions
Tetanospasmin is produced by what?
vegetative forms of Clostridium tetani
What does tetanospasmin do?
trismus (75%) = jaw tightness
neck rigidity
What is the treatment of tetanus?
benzodiazepines
muscle relaxants
- neutralize exotoxin; human anti-tetanus immunoglobin; pcn
How do infants get tetanus?
non-sterile materials used to cut the umbilical cords
What are the 4 types of pneumonia?
- community-acquired (streptococcus pneumoniae = most common)
- Aspiration (s/s can include fulminating arterial hypoxemia, airway obstruction, atelectasis, penumonia)
- postoperative
- ventilator-associated
What is included in the presentation of pneumonia?
fever, chest pain, dyspnea, fatigue, rigors, cough, sputum
pt history (travel, caves, diving, birds/sheep, immunocompromised)
chest xray, + cultures, ↑ WBC
What is the prevention of pneumonia for adults 65 & older?
PPSV23 for pneumococcal pneumonia
& for those 19-65 who smoke cigarettes or suffer from other health conditions
Anesthesia management in pneumonia
- delay if possible
- avoid fluid overload
- LPV [pts are PEEP dependent]; use lowest FiO2 possible, same vent settings as in ICU
- suctioning pt
- maintain antibiotics/viral/fungal schedule
Severe acute respiratory viral illness
highly virulent & high mortality
H5N1 = Influenza A = bird flu
COVID strains, MERS-CoV, SARS-CoV
S/s of severe acute respiratory viral illess
nonspecific
fever, headache, diarrhea, respiratory distress, hemoptysis
Treatment of viral respiratory infections
- prevention
- vaccines
- NEURAMINIDASE INHIBITORS; zanamirvir, peramivir, oseltamivir (tamiflu), baloxavir marboxil)
* *only give in the first 48 hours of symptoms - supportive care
Anesthesia management of viral illnesses
- LPV / symptom management
- barrier precautions
- filters on both sides of breathing circuit (protect pt & ventilator)
- clean room with EPA approved hospital disinfectant
- prioritize procedures if possible
Who should intubate pts with active viral illnesses?
most experienced anesthesia professions available
- wear PPE
What PPE should be worn when manipulating the airway of an active viral infection?
mask, gown, gloves, face-shield
N95 or PAPR
What kind of intubation should be avoided in patients with active viral illness?
AVOID awake fiberoptic intubation;
standard can be avoided
[RSI is preferred to avoid manual ventilation & aerosolization of particles]
What type of tidal volumes should be used when manually ventilating a patient with an active viral illness?
small, to limit aerosolization of particles
What is a negative pressure room / recommendations?
minimum of 15 air exchanges per hour with a minimum of 3 air changes of outdoor air per hour
anteroom is needed
OPERATING ROOMS ARE POSITIVE PRESSURE
What type of ultraviolet rays are used by hospitals?
UV-C
What is a HEPA filter?
High-efficiency particulate air (HEPA)
- theoretically mechanically removes 99.97% of pollen, dust, mold, bacteria, and any AIRBOURNE particles with size 0.3microns
What are HMEFs?
Heat & Moisture Exchange medium with ELECTROSTATIC FILTER
- protects pts from cross infx. Filter uses an ELECTROSTATIC medium of permanently charged bipolar rectangular split fibers to capture airborne particles
What are bacterial/viral filters?
prevent transmission of bacteria & viruses and cross-infection;
filter medium is constructed of permanently charged bipolar rectangular split fibers that are able to capture airborne particles
Where are air filters available?
- HVAC systems for isolation rooms
- AGM breathing circuits
- Exp & Insp limbs
- Portable [filters air when it is not an isolation room] ** useful in positive pressure ORs
What aerobe causes tuberculosis?
mycobacterium tuberculosis
*an obligate aerobe
What are the s/s of tuberculosis?
cough, anorexia, weight loss, night sweats, chest pain
apical or subapical infiltrates, bilateral upper lobe infiltration with the presence of cavitation
What is Pott’s disease?
tuberculous vertebral osteomyelitis; common manifestation of extrapulmonary TB
What is Mantoux’s test?
most common test for TB = tuberculin skin test
Treatment of TB
- can be resistant to 2nd line treatment
- chemo with isoniazid
- DELAY case
- negative pressure room
- N95 / HEPA filters
Caution to avoid spine injury during airway manipulation
What skin lesions are related to heroin use?
abscesses, celluliitis, ulcerations, scaring, thrombosed veins
Four leading drugs of abuse
prescription pain killers
heroin
fentanyl
carfentanil
Pulmonary disease related to drugs of abuse
edema septic embolism lung abscess opportunistic infections foreign body granulomas from talc
Infections related to drugs of abuse
skin & SQ tissue
heart valves
liver
lungs
*ENDOCARDITIS; right side heart valves [esp tricuspid], d/t contaminated needles - most by staphylococcus aureus
Acquired Immunodeficiency Syndrome
infx by human immunodeficiency virus;
destroys CD4+ T-cells & leads to profound immunodeficiency
The timeline of HIV infection
- acute seroconversion upon infection (high viral load)
- decrease in viremia after several months d/t pt immune response.
involution of lymph nodes & concomitant DECREASE in T-HELPER LYMPHOCYTES (CD4 T cells) & increase in viral load - Pneumocystis pneumonia does not usually occur until the CD4 count is less than 200 cells /mL
3 phases of HIV
- Acute phase
- Chronic phase
- AIDS
Seroconversion of HIV occurs when?
within 3-7 weeks of exposure
When is the “latent” HIV infection?
chronic phase; eventual decline in CD4 T-cells
AIDS development from HIV
progressive loss of CD4+T cells leading to PROFOUND IMMUNE DEFICIENCY
- high incidence of opportunistic infections
- progressive ENCEPHALOPATHY
Do HEPA filters provide humidification?
NO!
only mechanical filtration of particles
Are HEMF filters mechanical or electrostatic?
electrostatic
What happens during the acute phase of HIV infection?
virus enters through the mucosa.
infects & destroys CD4+ T cells
→ seroconversion usually within 3-7 weeks of exposure
systemic s/s resembling other infection
What happens during the chronic phase of HIV infection?
virus replicates in SECONDARY lymphoid organs
s/s are “latent”
→ eventual decline in CD4+ T cells
What happens during the AIDS phase of HIV infection?
[the continued loss of CD4+ T cells leads to eventual] profound immune deficiency
→ high incidence of opportunistic infections
→ progressive ENCEPHALOPATHY
What is the most sensitive test for HIV?
nucleic acid testing of HIV RNA
How is AIDS diagnosed in HIV+ patients?
one of the AIDS-defining diagnoses is present
What does the treatment for HIV/AIDS look like?
combination of antiviral drugs
→ highly active antiretroviral therapy [HAART]
*virus is NOT eradicated
What are the side effects of HAART?
↑ lipids
insulin resistance
peripheral neuropathy
premature cardio/renal/liver disease
→ INCREASED RISK of cancer & cardiovascular disease when on HAART therapy....... unknown why this happens..
Anesthetic considerations of HIV/AIDS
patients are subjected to LONG TERM METABOLIC COMPLICATIONS
- ↑ lipids - glucose intolerance → can result in DM, CAD, CV dz
What pre-op labs should be checked when a patient has HIV/AIDS?
CBC metabolic panel renal function LFTs Coags Chest x-ray ECG
?CD4+ count & viral load won’t likely change anesthesia management
What can cause neuraxial anesthesia to be precluded in HIV/AIDS patients?
focal neurological lesions = increased ICP
**neurological involvement may make SUCCINYLCHOLINE HAZARDOUS
Who must be notified if a student experiences a biological or chemical exposure in clinical?
- Duke Employee Occupational Health & Wellness (EOHW) safety hotline
↓ notify IN WRITING
- Director [Dr. Simmons]
- Clinical Education Coordinator [Dr. Pitman]
- Advisor
- Clinical Site Coordinator or chief CRNA
Who must be notified if a critical incident occurs?
ie. dental damage, CODE, intraop death, corneal abrasions, etc
↓ notify IN WRITING
- Director [Dr. Simmons]
- Clinical Education Coordinator [Dr. Pitman]
- Advisor
- Clinical Site Coordinator
Who must be notified of events involving students’ physical or mental health or safety?
ie. syncope, illness in the OR, falls, accidents, etc
must report to
- Program Director [Dr. Simmons] and Clinical Education *Coordinator [Dr. Pitman]
- Clinical Site Coordinator or chief CRNA
Standard precautions applies to who?
All patients. regardless of suspected or confirmed infection or colonization status
What is included in standard precautions?
- hand hygiene
- safe injection practices
- respiratory hygiene & cough etiquette
- environmental cleaning & disinfection
- reprocessing of reusable medical equipment
What is included in contact precautions?
- gown
- gloves
- dedicated equipment (stethoscope, BP cuff)
- private room or shared room with same pathogen
What are 5 pathogens that require contact isolation?
- Norovirus
- C.diff
- scabies
- MSSA
- MRSA
What are enhanced barrier precautions?
expand the use of PPE beyond situations in which exposure to blood & body fluids is anticipated
What care activities require enhanced barrier precautions?
- toilet
- airway care
- wound care
Droplets are spread by:
coughing, sneezing, talking
What are 8 pathogens that require droplet precautions?
- meningitis
- TB
- Rash petechial w/ fever
- RSV
- adenovirus
- influenza
- SARS-CoV
- avian influenza
What patients require airborne precautions?
known or suspected to be infected with pathogens transmitted by the airborne route
What are 7 pathogens transmitted via an airborne route?
- tuberculosis
- measles (rubeola)
- chickenpox
- disseminated herpes zoster
- varicella-zoster
- herpes simplex
- variola (smallpox)
