Paediatrics Flashcards
Definition of Pneumonia
Inflammation of lung alveoli, impairs gaseous exchange as they’re filled with blood, mucous, fluid and/or cellular infiltrates.
Pathophysiology of Pneumonia
Invasion and growth of a pathogen in parenchyma of lungs = inflammation and infiltration by neutrophils.
neutrophils release cytokines which activate immune response and lead to pyrexia(FEVER)
fluid and pus accumulates in the alveoli = impaired gas exchange because diffusion distance increases and SA decreases.
leads to hypoxia
Risk Factors of Pneumonia
Age <5 or >65
Smoking
Recent RTI
Chronic respiratory disease
Immunosuppression
IVDU
Co-morbidities - diabetes, cvd
alcoholism
Aspiration risk - Parkinson’s or neuro disease, or oesophageal obstruction
3 classifications of Pneumonia
Hospital - Acquired - Acute Nosocomial LTRI 48 hrs after hospital admission.
Community Acquired - pneumonia acquired outside.
Aspiration - (Mendelson’s Syndrome) - Pts with dysphagia (stroke,dementia,epilepsy,ms,parkinsons, MND) - unsafe swallowing - food goes into bronchial tree. Patients with gastric emptying issues or issues with their cough could have oropharyngeal aspirators containing gastric acid and aerobic/anaerobic bacteria. - acid and bacteria = inflammation=chemical pneumonitis
Explain Hospital Acquired Pneumonia
48 hours after hospital admission
Early HAP - less than 5 of admission. - Strep pneumoniae cause.
Late HAP - over 5 days of admission
causes:
S aureus - including MRSA
Gram Neg : pseudomonas aeurginosa, Haemophilus influenzae
Intestinal Gram Neg bacteria: E coli, actinobacteria, klebsiella.
Explain Community Acquired Pneumonia
Similar to any other LTRI
common causes:
strep pneumoniae
haemophilus influenzae
s aureus and mrsa
chlamydia psittaci and clamydia pneumoniae
influenza virus
Risk Factors of Aspiration Pneumonia
Risk factors:
1. neuro abnormalities - impaired conciousness, stroke, myasthenia gravis, bulbar palsy (bilateral impairement of CN 9,10,11,12), MS, dementia, parkinsion, MND
2. alcoholism
3. general anaesthesia, surgery
4. achalasia
5. gord
6. intubation
7. poor dental hygiene and oral infection
8. impaired mucociliary clearance
Where does Aspiration Pneumonia most commonly affect?
Right middle and lower lung - wider and more vertical than left bronchus - facilitating passage of aspirates.
Causative Agents of Aspiration Pneumonia
Aerobic - strep pneumoniae, staph aureus, Haemophilus influenzae, pseduomonas, aeruginosa
Anaerobic - klebsiella (aspiration lobar pneumonia in alcoholics), bacteroids, prevotella, fusobacterium, peptostreptococcus
3 categories of causative agents of pneumonia
Bacteria - MOST COMMON CAUSE. - STREP PNEUMONIA (80%) - H INFLUENZAE - MYCOPLASMA PNEUMONIAE - S Aureus - legionella, klebsiella
Viruses - influenza (most common in adults), rsv, sars-cov2, parainfluenza
Fungi - very rare - pneumocystis jirovecci in HIv+ people with cd4+ count <200 cells/uL
Presentation of Pneumonia
Cough with purulent sputum
Dyspnoea
Chest Pain - pleuritic
fever
malaise
rigors - sudden cold and shivering followed by fever and excessive sweating
systemic infection signs - pyrexia, tachy, hypotension, confusion, tachypnoea
Examination Findings in Pneumonia
Low ox sats
Auscultation - reduced breath sounds bronchial breathing - hard and loud sounds on inspiration and expiration, crepitations
dullness on percussion
increased vocal resonance
pleural rub
Scoring System for Pneumina
CRB65
C - CONFUSION - MENTAL TEST SCORE <8/10
U - Urea >7 mmol/L
R - RESP RATE - >30/MIN
B - BP - <90mmHg (Systolic) and/or <60 mmHg diastolic
65 - >65 yrs
everything is 1 pt.
stratified for risk of death.
0 - mortality - <1%
1/2 - 1-10%
3/4 - >10%
in hospital curb65 otherwise CRB65
0 - 0.7%
1 - 3.2%
2 - 13%
3 - 17%
4 - 41.5 %
5 - 57%
Tx based on CURB 65
IF
0-1 - TREAT AS OUTPATIENT
2 - SHORT STAY IN HOSPITAL OR WATCH VERY CLOSE AS OUTPATIENT
3-5 - REQUIRES HOSPITALISATION WITH CONSIDERATION OF ICU.
Investigations of Pneumonia
ABG
BLOODS - FBC (WCC), U+E (curb65), LFT, ESR/CRP
BLOOD CULTURE
SPUTUM - for MC+S
NAAT - look for mycoplasma pneumonia
URINE ANTIGEN - for legionella and pneumococcal pneumonia
LEGIONELLA ANTIBODIES - for high risk pts.
CXR - identify lobar,multi-lobar, cavitation and signs of pleural effusion. consolidation is seen in infection areas and may also show effusion.
Management of Pneumonia (Adults)
CURB65 tells you level of care needed
0/1 - home care
2 - hospital care
3+ - icu
no matter severity:
1. o2 sats above 94% or 88% in copd.
2. maintain fluid balance
3. analgesia - if pleuritic chest pain. paracetamol sufficient.
low - severity CAP - 5 day abx
1. amoxicillin
2. erythromycin/clarithromycin or doxycycline if pt has penicillin allergy.
moderate - severity CAP - 5 DAY DUAL ABX THERAPY
AMOXICILLIN + ERYTHROMYCIN/CLARITHROMYCIN
DOXYCYCLINE IF PENICILLIN ALLERGY - REPLACE AMOXI
HIGH SEVERITY cap - 5 DAY COURSE OF DUAL ABX
1. CO-AMOXICLAV + ERYTHROMYCIN/CLARITHROMYCIN
SWAP AMOXI FOR LEVOFLOXACIN IF PENICILLIN ALLERGY.
PREGNANCY : GIVE ERYTHROMYCIN
IN Pneumonia management how should abx be given
orally if possible
if iv, review every 48 hrs consider switching
repeat cxr at 6 weeks after resolution - ensure consolidation has resolved and no underlying abnormality.
When should I repeat a cxr after tx of pneumonia
repeat cxr at 6 weeks after resolution - ensure consolidation has resolved and no underlying abnormality.
Management of CAP in children
1st line : amoxicillin
2. clarithromycin/erythromycin - added if no response to 1st line or if mycoplasma or chlamydia infection suspected.
3. co-amoxiclav if concomitant influence infection present.