Febrile: 90 Hypotensive: SBP 20

LRTI Flashcards by Hannah Walters

Lower respiratory tract

Starts at the trachea–>bronchi–>bronchioles–>alveoli

Alveoli–>site of gas exchange where pneumonia occurs

How well did you know this?

Not at all

Perfectly

Nasopharynx

Nasal hair–>net captures pathogens
IgA secretion–>binds to pathogens
Fibronectin–>binds to pathogens

How well did you know this?

Not at all

Perfectly

Oropharynx

Saliva–>form that can remove bacteria or transfer

Slough epithelial cells–>gets rid of attached bacteria to collect in saliva

How well did you know this?

Not at all

Perfectly

Trachea/bronchi

Cough
Mucociliary apparatus (cilia)
Epiglottic reflux

How well did you know this?

Not at all

Perfectly

Alveoli

Alveolar lining fluid–>reduce binding to pathogens
Macrophages + PMN–>innate immunity
Cell-mediated immunity–>T and B cells

How well did you know this?

Not at all

Perfectly

Pathogen-mediated

Surface adhesions–>grab the cell
Pili–>grab the cell
Exotoxins–>fight immune cells
Enzymes–>fight immune cells

How well did you know this?

Not at all

Perfectly

Host interventions

Smoking–>decreased mucociliary apparatus
Alcohol
Altered consciousness
Endotracheal tubes

How well did you know this?

Not at all

Perfectly

Host-disease States

Immunosuppression
Diabetes
Asplenia–>decreased immune system
Elderly–>decreased immune system

How well did you know this?

Not at all

Perfectly

What is community-acquired pneumonia?

Pneumonia that developed outside of the hospital or within 48 hours of hospital admission

Most common infection-related hospitalization and mortality in the US

How well did you know this?

Not at all

Perfectly

Pathogenesis of CAP

Aspiration–>most common with bacterial
- occurs during healthy individuals and sleep
- organisms are usually cleared if host defenses functioning properly

Aerosolization–>most common with bacterial
- direct inhalation of pathogen in droplet nuclei form

Bloodborne

How well did you know this?

Not at all

Perfectly

Streptococcus pneumoniae (gram +)

Prevalence: asplenia, immunocompromised, chemo

Resistance: penicillin, macrolide
- Age < 6 or > 65
- Prior antibiotics
- Recent hospitalization
- Close quarters
- Co-morbid conditions

How well did you know this?

Not at all

Perfectly

Haemophilus influenzae

gram (-)

How well did you know this?

Not at all

Perfectly

Legionella pneumophila–> atypical

Spread: aerosolization
Risk: older males, chronic bronchitis, smokers, immunocompromised

How well did you know this?

Not at all

Perfectly

Chlamydia pneumoniae

atypical

How well did you know this?

Not at all

Perfectly

Mycoplasma pneumoniae–> atypical

Spread: person-to-person contact

2-3 week incubation period followed by slow onset of symptoms
- persistant, non-productive cough–> “walking pneumonia”

How well did you know this?

Not at all

Perfectly

Staphylococcus aureus

Prevalence: very low

Risk factors for MRSA
- 2-14 days post influenza
- Previous MRSA infection
- Previous hospitalization
- Previous IV antibiotic

Predictive values: 95-99% negative, 56.8% positive

How well did you know this?

Not at all

Perfectly

Classic presentation

Sudden onset

Fever, chills, pleuritic chest pain, SOB, productive cough

Gradual onset with mycoplasma and chlamydia

How well did you know this?

Not at all

Perfectly

Elderly presentation

May be absent

Decreased functional status, weakness, mental status changes

How well did you know this?

Not at all

Perfectly

Vitals

Study These Flashcards

Febrile: < 38 C
Tachycardia: HR > 90
Hypotensive: SBP < 90
Tachypnea: RR > 20

Labs

Study These Flashcards

WBC–>leukocytosis
SCr (elevated), BUN (elevated), LFTs
Low pulse oximetry
Nasopharyngeal PCR swab–> MRSA, viral
Urinary antigen tests–> strep pneumo, legionella

Major criteria for severe CAP

Study These Flashcards

Need 1

Septic shock requiring vasopressors

Respiratory failure required mechanical ventilation

Minor criteria for severe CAP

Study These Flashcards

Need 3

RR > 30
BUN > 20
WBC < 4,000
Plt < 100,000
T < 36 C
SBP < 90
Multilobe infiltrates
Confusion/disorientation

Diagnosis

Study These Flashcards

Chest radiography: Recommended for all patients for CAP
- Dense lobar consolidation/infiltrates = bacterial origin
- Patchy, diffuse, interstitial infiltrates = atypical or viral

Sputum: Color, amount, consistency, odor

Procalcitonin: Biomarker specifically for bacterial
- Dictates duration, not antibiotics

Blood culture–>only used in severe

Respiratory culture–>only used in severe
- Negative in 40-50% in patients with CAP

Supportive treatment

Study These Flashcards

Humidified O2
Bronchodilators
Fluids
Chest physiotherapy

Empiric therapy-->OUTPATIENT Healthy, no comorbidities/risk factors

Minimum of 5 total days Amoxicillin 1 g PO q8h Doxycycline 100 mg PO BID Azithromycin (z-pak)-->ONLY IF MACROLIDES RESISTANCE < 25%

Empiric therapy-->OUTPATIENT Healthy, comorbidities/risk factors

Heart, lung, renal, DM, alcoholism, malignancy, immunosuppression Respiratory FQ (Levofloxacin or Moxifloxacin) Beta-lactam + macrolide/doxycycline-->preferred - Augmentin - Cefuroxime - Cefpodoxime

Empiric therapy--> INPATIENT Non-severe: no MRSA/P, aeruginosa risk factors

Respiratory FQ (Levofloxacin or Moxifloxacin) Beta-lactam + macrolide/doxycycline-->preferred - Unasyn - Ceftriaxone

Empiric therapy-->INPATIENT Severe CAP: no MRSA/P. aeruginosa risk factors

Respiratory FQ + Beta-lactam Beta-lactam + macrolide/doxycycline-->preferred - Unasyn - Ceftriaxone

If patient has MRSA risk factors

Above agents + vancomycin/linezolid

P. aeruginosa risk factors

Previous isolated infection, previous hospitalization in 90 days Above agents + Zosyn/cefepime/meropenem

ONLY USE STEROIDS IF CAP + SEPTIC SHOCK

What is HAP/VAP?

HAP: pneumonia occurring > 48 hours after hospital admission VAP: pneumonia occurring > 48 hours after endotracheal intubation

Pathogenesis of HAP/VAP

Micro-aspiration of oropharnygenal secretions that colonized with bacteria - Gram (+) colonization-->3-5 days-->gram (-) organism Aspiration Direct inoculation Hematogenous

Common pathogens of HAP/VAP

Gram (-): P. aeruginosa, enterbacteriales, acinetobacter Gram (+): Staphylococcus aureus

Risk factors for HAP/VAP

Age Duration of hospitalization Endotracheal intubation Nasogastric tube Surgery Previous antibiotic therapy Severity of comorbid disease Altered mental status

Risk factors for MDR HAP

Prior IV antibiotic use within 90 days

Risk factors for MRSA HAP/VAP

Prior IV antibiotic use within 90 days

Risk factors for P. aeruginosa MDR

Prior IV antibiotic use within 90 days

Risk factors for MDR VAP

Prior IV antibiotic use within 90 days Septic shock at time of diagnosis Acute respiratory distress syndrome prior to diagnosis Acute renal replacement therapy prior to diagnosis > 5 days hospitalization prior to diagnosis

Microbiology Testing

Respiratory cultures-->recommended for all patients -Noninvasive> invasive - If invasive--> BAL > 10 ^4-->diagnosis

Diagnosis for HAP/VAP

no gold standard Timing--> 48 hours from admission Presentation-->clinical signs + new ling infiltrates

HAP-->low risk for mortality (no septic shock or ventilation)

Goal: MSSA + P. aeruginosa Zosyn, Cefepime, Meropenem, Imipenem, Levofloxacin

HAP-->low risk for mortality (no septic shock or ventilation) + MRSA

Zosyn, Cefepime, Meropenem, Imipenem, Levofloxacin + Vancomycin/Linezolid

HAP-->high risk for mortality (septic shock or ventilation) + MRSA

Goal: MRSA + P. aeruginosa 2 of the following (1 b-lactam + 1 non-b-lactam) Zosyn, Cefepime, Meropenem, Imipenem, Levofloxacin, Tobramycin/Amikacin+ Vancomycin/Linezolid

VAP

Goal: MRSA + P. aeruginosa Zosyn, Cefepime, Meropenem, Imipenem, Levofloxacin, Tobramycin/Amikacin+ Vancomycin/Linezolid

Non-beta-lactam considerations

Daptomycin-->never use for LRTI Aminoglycosides-->recommend against monotherapy Polymyxins-->reserved for pts with high prevalence of MDR Tigecycline-->good for polymicrobial infections

Duration for HAP/VAP

7 days if clinically stable

LRTI Flashcards

(47 cards)