Journal Review On Aspiration Pneumonia Published By NEJM on 2019

1. ASPIRATION PNEUMONIA
Presented by:- Dr. Diptiman Behera
Preceptor:- Asst. Prof. Dr. Sarita
Behera
Department of General Medicine
S.C.B.M.C.H

3. Introduction

4. Aspiration
Aspiration
pneumonia
Infection
caused by
specific
microorganism
Chemical
pneumonitis
Inflammatory
reaction to
irritative gastric
contents

5. Aspiration Pneumonia
 Considered not as a distinct entity but
as a continuum that also includes
community- acquired and hospital
acquired pneumonias
 5 to 15% of cases of community-
acquired pneumonia (CAP)
 Figures for hospital acquired
pneumonia are unavailable

6. Pathogenesis

7.  50% of healthy persons aspirate during
sleep, which usually goes unrecognized,
and has no sequelae.
 Determinants who gets infection?
◦ Frequency of aspiration,
◦ Volume of the aspiration,
◦ Character of the aspirated material,
◦ Host defenses

8.  In healthy state, the immune tone of
airways and alveoli – calibrated by the
bacteria constituting lung microbiota
 Stability of the lung microbiome is
maintained by – balance of immigration
and elimination of bacteria and by
feedback loops
 Dysbiosis( change in lung microbiota ) –
impair pulmonary defenses

9. Changing Microbiologic
Concept

10.  In the 1970s, anaerobes with or without
aerobes were the predominant
pathogens (e.g- Peptostreptococcus
sp., Fusobacterium sp., Bacteroides
sp.)
 More recently, there has been a shift to
aerobic bacteria (usually associated
with community- and hospital-acquired
pneumonias) & the anaerobes are
recovered less frequently (STUDY)

11.  The main isolates are
◦ Streptococcus pneumoniae,
◦ Staphylococcus aureus,
◦ Haemophilus influenzae, &
◦ Enterobacteriaceae in community-acquired
cases,
◦ whereas gram-negative bacilli, including
Pseudomonas aeruginosa, were found
without anaerobes in hospital-acquired
cases
◦ In cases of poor dental hygiene, the
anaerobes isolated are Porphyromonas
gingivalis, Treponema denticola, Prevotella,

12. Why such shift ?
 Mostly unclear
 But may be due to a shift in the
demographic characteristics of patients
 And earlier sampling today than in the
past.
 Prior studies often collected cultures later
in the illness, often after the development
of lung abscess or necrotising pneumonia
or empyema.

13. Risk Factors

14. • Head, neck & esophageal cancer, strictures causing dysphagia
• Neurologic diseases: seizures, multiple sclerosis, parkinsonism,
stroke, dementia
• COPD
• Mechanical ventilation extubation
Impaired
Swallowing
• Neurologic disease: Stroke
• Cardiac arrest
• Medications: Anti-psychotics, narcotics, anti-depressants
• General anesthesia
• Alcohol consumption
Impaired
Consciousness
• Reflux
• Tube Feeding ( Nasogastric feeding is better than percutaneous
enteral feeding)
Gastric contents
reaching lungs
• Medications & Alcohol
• Degenerative neurological diseases
• Impaired consciousness
Impaired cough
reflex

16. Clinical features

17. ASPIRATION PNEUMONIA CHEMICAL
PNEUMONITIS
ONSET OF
SYMPTOMS
HOURS TO A FEW DAYS SUDDEN
ONSET(MINUTES TO
HOURS)
SYMPTOMS FEVER, COUGH WITH
EXPECTORATION,TACHYPNEA,
SHOCK
DYSPNEA, HYPOXIA,
TACHYCARDIA, DIFFUSE
WHEEZE (NO FEVER)
CLINICALLY /
RADIOLOGIC
ALLY
DEPENDENT BRONCHOPULMONARY
SEGMENT INVOLVEMENT
( Aspirated while Supine—posterior
segment of upper lobe,usually Rt side or
superoir segments of either or both lower
lobes
Aspirated while Upright—Basal lung
B/L OPACITY ON CXR

18. DIAGNOSIS

19.  Clinical history (witnessed aspiration) & findings
 Risk factors
 Chest X-ray (may be negative in the early
course)
 CT scan of thorax
 Thoracentesis
 Bronchoalveolar lavage cultures
 Sr. Procalcitonin isn’t helpful (STUDY)

20. •68-year-old man
•History
of cough, blood in the
sputum, and a 6.8-kg weight
loss.
•He had
extensive tooth decay and
gingival inflammation.
•Didn’t drink alcohol or abuse
illicit drugs
•But did take an
antidepressant
known to cause somnolence.
•The radiograph shows a
cavitary infiltrate in the left
lower lobe and an infiltrate
RADIOGRAPH - A

21. RADIOGRAPH - B
•84-year-old man with
small-bowel
obstruction.
•Had repeated
episodes of vomiting,
leading to
•development of
bilateral lung infiltrates,
respiratory failure & the
acute respiratory
distress syndrome.
•Initial cultures were
sterile, but 1 week later,
he continued to have
lung infiltrates
and sputum culture
showed methicillin-
resistant

22. CT Thorax -1
•56-year-old man
•Had cough after
tooth extraction
performed with
local anesthesia.
•Known alcoholic.
•Shows a cavitary
infiltrate in the right
upper lobe
posteriorly
• Bronchoscopic
cultures revealed
Klebsiella
pneumoniae

23. •79-year-old
man with
dyspnea after
upper GI
endoscopy
•Complicated by
vomiting
•Shows new
bilateral
infiltrates in
posterior,
gravity-
dependent lung
segments
CT Thorax - 2

24. Treatment

25.  As documented pathogens have shifted
from anaerobes to aerobes, treatment
regimens have also evolved.
 Still anaerobes are common in patients
having severe periodontal disease & in
lung abscess, necrotising pneumonia
 Studies prove that for anaerobes in
lung, clindamycin is superior to
metronidazole (STUDY)

26. Algorithmic Approach to Antibiotic
Therapy for Aspiration Pneumonia
Antibiotic selection depends on
 The site of acquisition (the community, a
hospital, or a long term care facility) and
 Risk factors
1. for infection with multidrug-resistant
pathogens,
2. whether treated with broad-spectrum
antibiotics in the past 90 days or
hospitalised for at least 5 days &
3. Dental health

27. Clindamycin

28. Community acquired
1.Beta-lactams-
ampicillin–sulbactam,
amoxicillin–clavulanate,
ceftriaxone
OR
2.Fluoroquinolone
(levofloxacin, PLUS Clindamycin (If
anaerobes)
moxifloxacin)
OR
3.Carbapenem
(ertapenem)

30. Hospital acquired or long-term care acquired
Same T/T as that of CAP
But, if risk of MDR,
• Piperacillin–tazobactam,
• Cefepime
• Levofloxacin,
• Carbapenem (meropenem,imipenem)
• either Aminoglycoside or Colistin
• If MRSA, then PLUS Vancomycin or
Linezolid

31. Treatment contd..
 Duration :-
 Reassessment after 48 hours
 5-7 days if good clinical response
 Longer period for those with necrotizing
pneumonia, lung abscess, or empyema.
 No role of glucocorticoids
 Treatment can be modified or discontinued after
culture & sensitivity reports
 No role of antibiotics and steroid in chemical
pneumonitis even with an abnormal radiograph
 (exception- if the patient is severely ill, or has small bowel
obstruction or is on acid suppression therapy)

33. Prevention

34.  Stroke patients
 Early mobilisation & swallowing exercises (procedure)
 Soft diet with thickened liquids(nutritional
rehabilitation)
 RTF in semi-recumbent position
 Role of nasogastric tubes in preventing
aspiration pneumonia is uncertain (STUDY)
 Post-pyloric feeding is not superior to gastric
feeding & monitoring of post-feeding residual
volume may not minimize the risk of aspiration

35. Prevention contd..
 Antibiotic therapy for 24 hr in comatose
patients after emergency intubation(STUDY)
 Role of ACE inhibitors and Cilostazol
(STUDY)
 Role of chlorhexidine in oral hygiene
(STUDY)

37. Conclusions
 Diagnostic approach should be based on
clinical findings, risk factors and radioimaging
 Shift of pathogens, from anaerobes to
aerobes
 Clindamycin being superior to metronidazole
 Treatment should be based on risk factors
and culture
 No role of steroids
 Preventive measures in high risk patients

38. BIBLIOGRAPHY
 Mandell Lionel A. and Niederman Michael S., McMaster
University, Hamilton, Aspiration Pneumonia. N Engl J Med
2019;380:651-63.
 Mandell Lionel A., Wunderink Richard, J. Larry Jameson,
Anthony S. Fauci, Kasper, Hauser, Longo, Loscalzo, Harrison’s
Principles of Internal Medicine, Volume 1, Chapter 121, Pg 908-
918, Chapter 172, Pg 1231, 20th edition
 Marik Paul E. , Michael A. Grippi, Jack A. Elias, Jay A. Fishman
et al., Fishman's Pulmonary Diseases and Disorders, Chapter
69, Pg-2216-2238, 5th edition
 Seaton Douglas, Anthony Seaton, A. Gordon Leitch, Crofton and
Douglas's Respiratory Diseases, Chapter 13, Pg 412-414, 5th
edition
 Musher Daniel M. , Cecil, R. L. 1., Goldman, L., & Schafer A. I.,
(2012). Goldman's Cecil Medicine, Chapter 97 , Pg 618 , 25th