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An Ofcial Publication of the Society of Hospital Medicine Journal of Hospital Medicine® Published Online February 2019 E1
ONLINE FIRST FEBRUARY 20, 2019—REVIEW
Aspiration Pneumonia in Older Adults
Alexander Makhnevich, MD1,2*; Kenneth H Feldhamer, MD1,2; Charles L Kast, MD1,2; Liron Sinvani, MD1,2
1Northwell Health, Manhasset, New York; 2Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York.
Aspiration pneumonia refers to an infection of the
lung parenchyma in an individual who has inhaled a
bolus of endogenous ora that overwhelms the nat-
ural defenses of the respiratory system. It primarily
affects older adults with almost 80% of cases occurring in those
65 years and older.1 Compared with nonaspiration pneumonia,
aspiration pneumonia (whether community acquired or health-
care associated) results in more ICU stays, mechanical ventila-
tion, increased length of hospital stay, and higher mortality.2
The etiology of aspiration pneumonia comes from aspirated
bacteria from the oropharynx or stomach.
3
However, aspiration
alone is a common occurrence and does not always lead to clinical
pneumonia. Indeed, one study demonstrated that 45% of “nor-
mal subjects” aspirate in their sleep,
4
illustrating that our bodies
have evolved defense mechanisms to protect us from aspirated
bacteria. Thus, it is only when these systems are overwhelmed,
after compromise of both glottic closure and the cough reex in
addition to dysphagia,
3
that an infection manifests.
ASPIRATION PNEUMONITIS
Aspiration pneumonitis refers to a signicant inammation of
the lung parenchyma that results from inhalation of regurgitat-
ed gastric contents.5 It can produce fever, cough, wheezing,
shortness of breath, hypoxemia, leukocytosis, and a pulmonary
inltrate as well as lead to severe acute respiratory distress syn-
drome and even death. In the past, the use of antibiotics short-
ly after aspiration in patients who develop a fever, leukocytosis,
or a pulmonary inltrate was discouraged.5 Empiric antibiotics
were recommended only for patients who aspirate gastric con-
tents and who have conditions associated with colonization
of gastric contents, such as small-bowel obstruction.5 Yet, it is
difcult to distinguish aspiration pneumonitis from pneumo-
nia6 and there are no randomized trials in older adults to help
guide their management.
PRESENTATION OF ASPIRATION PNEUMONIA
Pneumonia in older adults can present in an atypical fashion.
In one study of community-acquired pneumonia (CAP), the
combination of cough, fever, and dyspnea is present in only
31% of patients, although separately, they are present in 67%,
64%, and 71% of patients, respectively. The same study also
showed that delirium was present in 45% of patients with CAP.7
Nonrespiratory symptoms were present during the initial pre-
sentation of CAP in 55% of patients, with confusion in 42%, and
falls in 16% of cases.8 The same is true of aspiration pneumonia
where altered mental status is seen in approximately 30% of
community-acquired aspiration pneumonia (CAAP) patients
and in 19% of continuing care facility patients with aspiration
pneumonia.2 Another study that compared CAP, CAAP, and
healthcare-associated aspiration pneumonia (HCAAP) showed
that confusion is present in 5.1%, 12.7%, and 18.6%, respec-
*Corresponding Author: Alexander Makhnevich, MD; E-mail: amakhnev@
northwell.edu; Telephone: (516) 562-2945; Twitter: @amakhnev1
Received: May 10, 2018; Revised: December 10, 2018;
Accepted: December 20, 2018
© 2019 Society of Hospital Medicine DOI 10.12788/jhm.3154
Aspiration pneumonia refers to an infection of the lung
parenchyma in an individual that has inhaled a bolus of
endogenous ora that overwhelms the natural defenses
of the respiratory system. While there are not universally
agreed upon criteria, the diagnosis can be made in patients
with the appropriate risk factors and clinical scenario, in
addition to a radiographic or an ultrasonographic image
of pneumonia in the typical dependent lung segment.
Treatment options for aspiration pneumonia vary based
on the site of acquisition (community-acquired aspiration
pneumonia [CAAP] versus healthcare-associated aspiration
pneumonia [HCAAP]), the risk for multidrug-resistant
(MDR) organisms, and severity of illness. Hospitalized
CAAP patients without severe illness and with no risk for
MDR organisms or Pseudomonas aeruginosa (PA) can
be treated with standard inpatient community-acquired
pneumonia therapy covering anaerobes. Patients with
CAAP and either of the following—risk factors for MDR
pathogens, septic shock, need for an intensive care
unit (ICU) admission, or mechanical ventilation—can be
considered for broader coverage against anaerobes,
methicillin-resistant Staphylococcus aureus (MRSA), and
PA. Severe aspiration pneumonia that originates in a
long-term care facility or HCAAP with one or more risk
factors for MDR organisms should be considered for similar
treatment. HCAAP with one or more risk factors for MDR
organisms or PA, plus septic shock, need for ICU admission
or mechanical ventilation should receive double coverage
for PA in addition to coverage for MRSA and anaerobes.
Multiple gaps in current understanding and management
of aspiration pneumonia require future research, with
a particular focus on antibiotic stewardship. Journal of
Hospital Medicine2019;14:XXX-XXX.© 2019 Society of
Hospital Medicine
Makhnevich et al | Aspiration Pneumonia in Older Adults
E2 Journal of Hospital Medicine® Published Online February 2019 An Ofcial Publication of the Society of Hospital Medicine
tively.9 The absence of fever in older adults is shown in stud-
ies where fever, dened as greater than or equal to 37.5°C,
is absent in 32% of the very old10 and in 40% of patients 65
years or older when it was dened as greater than 37°C.8 The
inconsistencies regarding typical symptoms of pneumonia in
the older adult population are also conrmed in nursing home
residents.11 Ultimately, it is important to remember that any
infection in older adults, especially in those residing in long-
term care facilities, may present with subtle ndings such as an
acute change in cognitive and functional status.12
Risk Factors for Aspiration Pneumonia
Risk factors for aspiration pneumonia, while not universally
agreed upon, are important to recognize as they increase the
probability of the diagnosis when present. A 2011 systematic
review identied age, male gender, lung disease, dysphagia,
and diabetes mellitus (level 2a), as well as severe dementia,
angiotensin I-converting enzyme deletion/deletion genotype,
and poor oral health (level 2b) as risk factors.13 In 2016, a panel
of experts reached a consensus (modied Delphi Method) on
the following risk factors for the diagnosis of aspiration pneu-
monia in nursing home residents: history of dysphagia, chok-
ing incident, tube feeding, neurologic disease, and cognitive
impairment. The presence of one or more of these risk factors
in the appropriate clinical setting may suggest a diagnosis of
aspiration pneumonia.14
Radiographic/Ultrasonographic Imaging
In the appropriate scenario, the diagnosis of aspiration pneu-
monia is supported with an image representative of pneumo-
nia. The pulmonary segment involved in aspiration pneumonia
depends on the position of the patient during the aspiration
event. If the aspiration event occurs while the patient is in the
recumbent position, development of pneumonia is more com-
mon in the posterior segments of the upper lobes and the api-
cal segments of the lower lobes; whereas if it occurs while the
patient is in an upright position, the location changes to the
basal segments of the lower lobes.3
Overall, the sensitivity of a chest X-ray to diagnose pneumo-
nia ranges between 32%-77.7%,15-17 suggesting that a signi-
cant proportion of patients suspected of having pneumonia in
past research studies, may have been misdiagnosed. Studies
using lung ultrasound to identify pneumonia demonstrate a
higher sensitivity, but additional research is needed to validate
these ndings.17-19 Noncontrast CT scans of the chest remain
the reference standard for diagnosing pneumonia and cur-
rently tend to have the largest impact on diagnosis and sub-
sequent treatment decisions.15,16,20,21 As a result, if radiation ex-
posure risks are not a concern for the patient, we recommend
utilizing noncontrast CT imaging whenever the diagnosis is in
doubt until future research elucidates the most appropriate
approach to imaging.
Diagnosis
Diagnosing aspiration pneumonia is difcult, in part because
there is no universal denition or set of diagnostic criteria. The
diagnosis of aspiration pneumonia is supported by the fulll-
ment of three criteria. First, appropriate risk factors for aspira-
tion, as documented above, should be present. Second, there
should be evidence of clinical signs and symptoms of pneu-
monia (typical or atypical). Third, radiographic representation
of pneumonia in a dependent pulmonary segment conrms
the diagnosis. Once these criteria are met, it is important to
distinguish between CAAP and HCAAP with particular atten-
tion to risk factors for multidrug-resistant (MDR) organisms and
Pseudomonas aeruginosa (PA).
MICROBIOLOGY
Many studies have tried to determine the exact bacterial eti-
ology of aspiration pneumonia as documented in the Table.
Even when an ideal method is used to obtain a good sam-
ple, however, the results are limited by other variables in the
study. For example, in studies that use protected brush spec-
imens and protected bronchoalveolar lavage to acquire sam-
ples for culture, many patients received antibiotics prior to
sampling, and the studies are small (Table). Although anaer-
obes have traditionally been implicated in aspiration pneu-
monia, only El-Solh et al.22 were able to culture a signicant
proportion of anaerobes. The study, however, was limited to
institutionalized older adults requiring mechanical ventilation
and it did not require the typical radiographic location for
aspiration pneumonia. Even under the best circumstances,
it is difcult to determine causality because the antibiotics
used to treat these cases of aspiration pneumonia cover a
broad range of organisms. Based on the studies in the Table,
causative organisms may include Streptococcus pneumo-
niae, Haemophilus inuenzae, Staphylococcus aureus, and
gram-negative rods in addition to traditional organisms clas-
sically thought to cause aspiration pneumonia-anaerobes.
Microbiologic etiology, however, may also be insinuated from
the studies discussed in the therapeutic strategies section
below as some include antibiotics with limited antimicrobial
activity.
Therapeutic Strategies
The management of aspiration pneumonia has evolved signi-
cantly since it was rst studied in the 1970s because of the de-
velopment of antibiotic resistance patterns, newer antibiotics,
and increasing information on the diversity of pathogens in-
volved in each subset of aspiration syndromes. The antimicro-
bial treatment of aspiration pneumonia was classically directed
against anaerobic pathogens; treatment of these infections,
however, was extrapolated from studies of pulmonary abscess-
es and other anaerobic pulmonary infections.
A randomized controlled trial in the mid-1980s compar-
ing penicillin and clindamycin demonstrated a signicantly
improved cure rate in the clindamycin group.23 A follow-up
study in 1990 implicated a signicant number of penicillin-re-
sistant Bacteroides infections—the majority of these infections
were subsequently reclassied as Prevotella melaninogeni-
ca—as the cause for high rates of penicillin resistance in lung
abscesses and necrotizing pneumonias, further supporting
Aspiration Pneumonia in Older Adults | Makhnevich et al
An Ofcial Publication of the Society of Hospital Medicine Journal of Hospital Medicine® Published Online February 2019 E3
TABLE. Determining Bacterial Etiology of Aspiration Pneumonia
Study
Radiographic Criteria
for Diagnosis Microbiology Limitations
Mier et al.49 (1993)
Prospective
Alveolar opacity Blood culture:
Streptococcus pneumoniae (1 patient)
Staphylococcus aureus (1 patient)
Protected brush specimen isolates:
Staphylococcus aureus 22%
Streptococcus pneumonia 15%
Pseudomonas aeruginosa 11%
Haemophilus inuenzae 7.4%
Escherichia coli 7.4%
Proteus mirabilis 7.4%
Streptococcus sp. 7.4%
Klebsiella pneumoniae 3.7%
Enterobacter cloacae 3.7%
Serratia marcescens 3.7%
Streptococcus viridans 3.7%
Morganella morgannii 3.7%
Candida albicans 3.7%
Small sample size; only ICU patientsa; alveolar opacity did not have to
be in a dependent lobe; antibiotics were administered before protected
brush specimen (PBS) cultures were obtained
Marik et al.50 (1999)
Prospective
Alveolar inltrate Protected specimen brush sampling and mini-bronchoalveolar lavage
isolates:
Enterobacter spp 17.6%
Streptococcus pneumoniae 11.7%
Methicillin-sensitive Staphylococcus aureus (MSSA) 11.7%
Haemophilus inuenzae 11.7%
Klebsiella pneumoniae 11.7%
Escherichia coli 11.7%
Flavobacterium spp 11.7%
Serratia spp 5.8%
V paravula 5.8%
Small sample size; all patients required mechanical ventilation;
inltrate did not have to be in dependent lobes; 48% of patients
received an antibiotic with anaerobic coverage in the 24 hours prior to
microbiologic sampling
El-Solh et al.22
(2003)
Prospective
Inltrate compatible with
pneumonia
Blood culture:
Streptococcus pneumoniae (1 patient)
Staphylococcus aureus (1 patient)
Klebsiella pneumonia (1 patient)
Protected bronchoalveolar lavage isolates:
Anaerobes 20.5% (Prevotella spp 11%, Fusobacterium spp 5.5%,
Bacteroides spp 2%,
Peptostreptococcus 2%)
Escherichia coli 20%
Klebsiella pneumoniae 15%
Staphylococcus aureus 15%
Serratia spp 13%
Proteus mirabilis 11%
Streptococcus spp 11%
Streptococcus pneumoniae 9%
Haemophilus inuenzae 4%
Pseudomonas aeruginosa 4%
Enterobacter cloacae 2%
Only institutionalized older adults requiring mechanical ventilation;
small sample size; inltrate did not have to be in dependent lobes;
does not specify when antibiotics were administered in relation to pro-
tected bronchoalveolar lavage cultures, although cultures were taken
within 4 hours of presentation to the emergency department
Kadowaki et al.33
(2005)
Randomized prospective
Inltrate in the posterior
segments of the lower lobes
Sputum culture isolates:
Klebsiella pneumoniae 30.8 %
Methicillin-resistant Staphylococcus aureus (MRSA) 14.1%
MSSA 11.5%
Enterobacter 7.7%
Haemophilus inuenzae 6.4%
Streptococcus pneumonia 6.4%
Serratia 5.1%
Pseudomonas aeruginosa 5.1%
Escherichia coli 3.8%
Citrobacter 2.6%
Sputum cultures are less reliable than PBS; the study did not docu-
ment the time antibiotics were administered in relation to sputum
acquisition; did not specify whether sputum cultures were processed
for anaerobes
Continued on page 000
Makhnevich et al | Aspiration Pneumonia in Older Adults
E4 Journal of Hospital Medicine® Published Online February 2019 An Ofcial Publication of the Society of Hospital Medicine
clindamycin as the treatment of choice for these infections.24
Amoxicillin-clavulanic acid (IV and PO regimens), studied in
the treatment of community-acquired necrotizing pneumonia/
lung abscess, shows good efcacy as well.25 This study also
attempted to elucidate the underlying causative organisms in
these patients. Organisms associated with CAP as well as an-
aerobic organisms were isolated, giving more credence to the
idea of broader coverage for aspiration pneumonia.
Community-Acquired Aspiration Pneumonia/Health-
care-Associated Aspiration Pneumonia
The importance of making a diagnostic distinction between
CAAP versus HCAAP is critical for management strategies. A
prospective population-based study demonstrated that ICU
length of stay and 30-day mortality is highest for HCAAP, fol-
lowed by CAAP, and lastly for those with CAP.9 Although some
studies use different nomenclature for identifying aspiration
TABLE. Determining Bacterial Etiology of Aspiration Pneumonia (continued)
Study
Radiographic Criteria
for Diagnosis Microbiology Limitations
Shariatzadeh et al.2 (2006)
Prospective
Pulmonary inltrate CAAP:
Blood cultureb:
Staphylococcus aureus 35.7%
Streptococcus pneumoniae 21.4%
Escherichia coli 14.3%
Sputum culturec:
Gram-negative bacilli 45%
Streptococcus pneumoniae 20%
Haemophilus inuenzae 20%
Continuing care facility aspiration pneumonia:
Blood cultured:
Gram-negative bacilli 40%
Streptococcus pneumoniae 20%
Staphylococcus aureus 20%
Sputum culturee:
Pseudomonas aeruginosa 43%
Gram-negative bacilli 29%
Staphylococcus aureus 21%
Inltrate did not have to be in dependent lobes; sputum cultures are
less reliable than PBS; sputum and blood cultures were not performed
on all patients; the study did not specify when antibiotics were
administered in relation to the acquisition of cultures; sputum culture
was not processed for anaerobes
Lanspa et al.9 (2013)
Retrospective
Radiographic evidence of
pneumonia
CAAP & HCAAPf:
Streptococcus pneumoniae 2.5% Enteric organisms 2.2%
MRSA 1.9%
Haemophilus sp, 1.8%
MSSA 1.6%
Pseudomonas 1.0%
Beta-hemolytic strep 0.7%
M. catarrhalis 0.3%
Neisseria sp. 0.7%
Other 1.6%
HCAAP patients had statistically signicant increased rates of enteric
bacteria causing infection.
Retrospective design; no clear denition of aspiration pneumonia; only
7.8% of patients had positive cultures (blood/tracheal); HCAP aspira-
tion patients lacked full criteria for HCAP; PBS was not used to obtain
culture samples; tracheal aspirate was the most common method used
for recovering an organism; the study did not specify when antibiotics
were administered in relation to the acquisition of cultures; recovery of
anaerobic organisms was limited to blood and pleural uid
Marumo et al.32 (2014)
Prospective cohort
New inltrate NHCAP (all culturesg):
Streptococcus pneumoniae 22%
MSSA 10%
Haemophilus inuenza 6%
Escherichia coli 1.7%
Pseudomonas aeruginosa 1.7%
MRSA 0.9%
Inltrate did not have to be in dependent lobes; NHCAP differed slight-
ly from standard HCAP denitions; only NHCAP patients with no risk
factors for MDR pathogens were evaluated; bacterial diagnosis was
established in only 47% of patients; PBS or protected bronchoalveolar
lavage was not used to obtain culture samples; the study did not speci-
fy when antibiotics were administered in relation to the acquisition of
cultures; anaerobic culture media was not used.
All isolates are expressed as a percentage of positive isolates (except for Lanspa et al. and Marumo et al.).
a 50% of patients had altered consciousness from a drug overdose, and an additional 15% aspirated because of intestinal obstruction; 72% of sterile PBS cultures were from drug overdose
patients. Most patients were not older adults.
b Blood cultures were positive in only 12% of CAAP patients who had blood cultures drawn.
c Sputum cultures were positive in 44% of CAAP patients who had sputum cultures.
d Blood cultures were positive in only 5% of continuing care facility patients who had blood cultures drawn.
e Sputum cultures were positive in 48% of continuing care facility patients who had sputum cultures.
f Expressed as a percentage of patients, rather than of isolates, who were carrying the pathogen.
g Expressed as a percentage of patients, rather than of isolates, who were carrying the pathogen.
Aspiration Pneumonia in Older Adults | Makhnevich et al
An Ofcial Publication of the Society of Hospital Medicine Journal of Hospital Medicine® Published Online February 2019 E5
pneumonia patients at risk for a wider array of microorganisms,
we attempt to standardize the language by using HCAAP. The
literature on nonaspiration pneumonia is changing from terms
such as CAP and healthcare-associated pneumonia (HCAP) to
pneumonia with the risk of MDR organisms. One study pro-
posed a new treatment algorithm for CAP based on the pres-
ence or absence of the following six risk factors: prior hospital-
ization of greater than or equal to two days in the preceding
90 days, immunosuppression, previous antibiotic use within
the preceding 90 days, use of gastric acid-suppressive agents,
tube feeding, and nonambulatory status.26 A similar approach
proposed years earlier for HCAP patients found the following
to be risk factors for MDR organisms: hospitalization in the
past 90 days, antibiotic therapy in the past six months, poor
functional status as dened by activities of daily living score,
and immune suppression.27 Other factors, such as structural
lung disease, that increase the risk of organisms resistant to
standard antibiotic treatment regimens28-31 should be consid-
ered in aspiration pneumonia as well. Aspiration pneumonia is
following a similar trajectory where the risk of MDR organisms
is taking precedence over the environment of acquisition. The
nal nomenclature will allow the healthcare provider to under-
stand the organisms that need to be targeted when choosing
an appropriate antibiotic treatment regimen.
There is evidence supporting the premise that CAAP and
nursing home patients with no risk factors for MDR organisms
can be treated with standard regimens used for patients with
CAP. A prospective cohort study in 2014 did not show any
statistically signicant differences in clinical outcomes in nurs-
ing and healthcare-associated aspiration pneumonia patients
(with no risks of MDR organisms) treated with azithromycin
versus ampicillin/sulbactam. However, only 36 patients were
included in the azithromycin arm, and the therapeutic choices
were made by the treating physician.32
A prospective study of 95 long-term care residents reported
that of those patients admitted to the ICU with severe aspi-
ration pneumonia, the causative organisms are gram-nega-
tive enteric bacilli in 49% of isolates, anaerobes in 16%, and
Staphylococcus aureus in 12%.22 This study mentioned that six
of seven anaerobic pneumonia cases had inadequate anaero-
bic coverage yet were effectively treated; based on the organ-
isms represented, however, the antibiotics administered did
provide some coverage.22 Prevotella was one of the common
anaerobic organisms that could be treated by levooxacin or
ceftriaxone/azithromycin, possibly explaining the success of
azithromycin in the study quoted previously.22,32 Therefore, al-
though anaerobic organisms still need to be considered, some
may be treated by traditional CAP coverage.22
In a 2005 randomized prospective study of 100 patients
aged 71 to 94 years, clindamycin was found to have clinical ef-
cacy equivalent to ampicillin-sulbactam and panipenem in the
treatment of mild-to-moderate aspiration pneumonia.33 Most
patients in this study are nursing home residents, and 53%
of sputum cultures in the clindamycin arm grew gram-nega-
tive rods. In contrast to the previous study, the signicance of
gram-negative rod infections in this population of patients,
with less severe infections, is called into question, as clindamy-
cin has no coverage against these organisms. This premise is
supported by a more recent study using azithromycin in nurs-
ing and healthcare-associated aspiration pneumonia patients,
mentioned previously.32 Taken together, these three studies
suggest that the severity of aspiration pneumonia may be a
risk factor that needs to be taken into account when consider-
ing broad-spectrum antimicrobial coverage.
While further research is needed to validate treatment ap-
proaches, based on the current literature we propose the fol-
lowing:
CAAP requiring hospitalization but without any of the fol-
lowing-risk for PA or MDR organisms, septic shock, the need
for ICU admission, or mechanical ventilation-can be treated
with standard CAP therapy that covers anaerobes.26,32-34 Pa-
tients with CAAP and either of the following—risk factors for
MDR organisms, septic shock, need for ICU admission, or me-
chanical ventilation—should be considered for broader cov-
erage with vancomycin or linezolid, antipseudomonal antibi-
otics, and anaerobic coverage. CAAP with specic risk for a
PA infection should be considered for two antipseudomonal
antibiotics (where only one can be a beta-lactam antibiotic,
and one has anaerobic coverage).
Severe HCAAP without risk for MDR organisms or PA but
with any of the following-septic shock, ICU admission, or me-
chanical ventilation-can be treated based on the 2016 Infec-
tious Diseases Society of America guideline recommendation
for hospital-acquired pneumonia, with a regimen that also
provides adequate anaerobic coverage.35 If patients have
HCAAP with one or more risk factors for MDR organisms, no
septic shock, and no need for ICU admission or mechanical
ventilation, provide coverage with a similar regimen. In con-
trast, HCAAP with risk factors for PA or severe HCAAP causing
septic shock, requiring ICU admission, or needing mechani-
cal ventilation, which occurs in the setting of one or more risk
factors for MDR organisms, or structural lung disease, should
receive two antipseudomonal antibiotics (where only one can
be a beta-lactam antibiotic and one has anaerobic coverage)
in addition to vancomycin or linezolid.
A recent systematic review demonstrates the paucity of
studies of ideal methodologic design which complicates the
ability to recommend, with condence, one guideline-based
antimicrobial regimen over another.36 Future studies may de-
termine that despite the severity of the infection, if patients
do not carry any risk for MDR pathogens or PA, they may only
require CAAP coverage. When a patient presents with an
acute infection, it is prudent to review previous cultures, and
although it may be necessary to treat with broad-spectrum an-
tibiotics initially, it is always important to narrow the spectrum
based on reliable culture results. If future studies support the
results of many studies cited in this article, we may be using
fewer antibiotics with narrower spectrums in the near future.
Prevention
Although the healthcare system has practices in place to pre-
vent aspiration pneumonia, the evidence supporting them
Makhnevich et al | Aspiration Pneumonia in Older Adults
E6 Journal of Hospital Medicine® Published Online February 2019 An Ofcial Publication of the Society of Hospital Medicine
are either inconclusive or not of ideal methodological design.
Two systematic reviews failed to show statistically signicant
decreases in rates of aspiration pneumonia or mortality using
the standard of care positioning strategies or thickened uids
in patients with chronic dysphagia.37,38 One study showed a de-
creased incidence of all pneumonia in dysphasic patients with
dementia or Parkinson disease when a chin-down posture (with
thin liquids) or thickened uids in a head-neutral position was
used. The study, however, has signicant limitations, including
a lack of a “no treatment” group for comparison, which did not
allow investigators to conclude that the decreased incidence
was from their interventions.39
There are preventive strategies that show a decreased risk of
aspiration pneumonia. Poor oral hygiene seems to be a modi-
able risk factor to establish better control of oral ora and de-
crease aspiration pneumonia. A systematic review of ve stud-
ies, evaluating the effects of oral healthcare on the incidence
of aspiration pneumonia in frail older people, found that tooth
brushing after each meal along with cleaning dentures once
a day and professional oral healthcare once a week decreas-
es febrile days, pneumonia, and dying from pneumonia.40 A
two-year historical cohort study using aromatherapy with black
pepper oil, followed by application of capsaicin troches, and
nally menthol gel, as the rst meal, leads to a decreased inci-
dence of pneumonia and febrile days in older adults with dys-
phagia.41 Well-designed validation studies may establish these
practices as the new standard of care for preventing pneumo-
nia in patients with dysphagia.
Feeding Tubes
Multiple studies show that in older adults with advanced de-
mentia there is no survival benet from percutaneous endo-
scopic gastrostomy (PEG) tube placement42-44 and more re-
cent systematic reviews also conclude that there is currently
no evidence to support the use of PEG tubes in this specic
population.45,46 In February 2013, as part of the American Board
of Internal Medicine Foundation Choosing Wisely® campaign,
the American Geriatrics Society advised providers not to rec-
ommend percutaneous feeding tubes in patients with ad-
vanced dementia, rather, “offer assisted oral feeding.”47 It is
worth noting, however, that none of the studies reviewed were
of ideal methodological design, so opinions may change with
future studies.
A more recent study compared liquid feeds versus semisol-
id feeds in patients with PEG tubes. The study shows a 22.2%
incidence of aspiration pneumonia in the liquid feed group,
which is comparable to prior studies, but the incidence of as-
piration pneumonia is only 2.2% in the semisolid feed group
(P < .005).48 A benet of this size warrants future studies for
validation.
CONCLUSION
Aspiration pneumonia leads to increased mortality when com-
pared with CAP and HCAP.2 Until future studies validate or re-
fute the current understanding surrounding its management,
the following should provide some guidance: aspiration pneu-
monia should be suspected in any individual with risk factors
of aspiration who presents with typical or atypical symptoms of
pneumonia. Conrmation of the diagnosis requires an image
representative of pneumonia in the typical dependent lung
segment on chest X-ray, lung ultrasound, or noncontrast CT
scan of the chest. Treatment of aspiration pneumonia should
take into account the site of acquisition, severity of illness,
and risk for MDR organisms as the causative organisms may
include Streptococcus pneumoniae, Haemophilus inuenzae,
Staphylococcus aureus, and gram-negative rods, in addition
to the traditional organisms classically thought to cause aspira-
tion pneumonia-anaerobes.
Disclosures: The authors have nothing to disclose.
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