1. doi: 10.1111/j.1742-1241.2007.01300.x
REVIEW ARTICLE
Aspiration syndromes: 10 clinical pearls every physician
should know
H. S. Paintal, W. G. Kuschner
Division of Pulmonary and SUMMARY
Critical Care Medicine, Stanford Review Criteria
Aspiration syndromes are clinically and pathologically classified into three sets of
University School of Medicine, • Articles were identified by searching PubMed
Palo Alto; and U.S. Department
disorders: (i) large airway mechanical obstruction caused by foreign bodies; (ii)
(1960 – December 2006) using the following
of Veterans Affairs Palo Alto aspiration pneumonitis; and (iii) aspiration pneumonia. In this article, we discuss search terms: aspiration pneumonia, aspiration
Health Care System, Palo Alto, the common clinical presentations, risk factors, radiographic features and methods pneumonitis, tracheo-bronchial foreign body
CA, USA
of management of these disorders. We highlight recent recommendations and con- aspiration, ventilator associated pneumonia,
Correspondence to:
troversies surrounding the prevention of aspiration pneumonia in the critically ill healthcare-associated pneumonia, Heimlich
Dr Ware G. Kuschner, patient. Finally, we review ethical dilemmas surrounding feeding and aspiration risk manoeuvre and swallow evaluation. We carried out
Veterans Affairs Palo Alto concerns in debilitated and demented patients. a complementary search on Google Scholar. We
Health Care System, 3801 reviewed evidence-based clinical practice guidelines
Miranda Avenue, Pulmonary on airway management produced by: (i) the
Section, Mail Stop 111 P, American Society of Anesthesiologists; (ii) the
Palo Alto, CA 94304, USA American College of Chest Physicians; and (iii) the
Tel.: + 1 650 493 5000 American Heart Association. We reviewed evidence-
(ext. 63544)
based clinical practice guidelines for the
Fax: + 1 650 852 3276
management of healthcare-associated pneumonia
Email: kuschner@stanford.edu
produced by the United States Centers for Disease
Disclosures Control and Prevention. We also reviewed
The authors have no financial evidence-based clinical practice guidelines for
disclosures or conflicts of nutritional support of high aspiration risk patients
interest to report. produced by the Canadian Critical Care Society and
the Canadian Society for Clinical Nutrition, and
Dietitians of Canada and evidence-based clinical
practice guidelines on enteral nutrition produced by
the European Society for Clinical Nutrition and
Metabolism.
facial trauma, loose teeth and dental appliances are
Pearl no. 1
commonly aspirated foreign bodies.
In 2001, an estimated 17,537 children in the USA
Infants, toddlers and adults with decreased under the age of 14 years were treated in emergency
sensorium are at highest risk of foreign body departments for choking-related episodes, with 160
aspiration resulting in tracheo-bronchial reported deaths. Rates were highest for infants aged
mechanical obstruction and asphyxiation. < 1 year and decreased with increasing age. Food
The cough, gag and swallowing reflexes protect the was implicated in almost 60% of cases (hard candy
respiratory tract in most children and adults. How- and gum were most common); 13% were associated
ever, infant and toddler exploratory behaviour that with coins (1). A typical presentation of tracheo-
includes placing small objects in the mouth increases bronchial obstruction resulting from aspiration
the risk of a catastrophic aspiration event in this age includes a history of eating or swallowing followed
group. Tracheo-bronchial foreign body aspiration by abrupt onset of difficulty speaking or breathing.
leads to varying degrees of obstruction of airflow Common signs and symptoms of foreign body aspir-
depending on the size of the object and the calibre ation include tachypnoea, tachycardia, wheezing,
of the airway. In young children, the most common cough and cyanosis.
objects aspirated are food, coins and toys. In adults ´
The term ‘cafe coronary’ stems from the presenta-
with decreased sensorium or in the setting of cranio- tion of a person suddenly choking on food (in a
ª 2007 The Authors
846 Journal compilation ª 2007 Blackwell Publishing Ltd Int J Clin Pract, May 2007, 61, 5, 846–852

2. Aspiration syndromes 847
´
cafe/restaurant) with sudden cyanosis, chest pressure patient. Rigid bronchoscopy must be performed
Message for the
or fainting that mimics an acute coronary syndrome. under general anaesthesia. Corticosteroids have a Clinic
In one of the first case series in the early 1960s, Hau- limited role to reduce airway inflammation, and anti- • Aspiration syndromes
gen reported nine cases, giving details of four cases. biotics are indicated only if the patient develops a are an important cause
The author noted that acute alcoholism, poor denti- postobstructive pneumonia. Imaging studies, inclu- of morbidity in
chronically debilitated
tion and atrocious table manners were precipitating ding plain radiographs and computed tomographs,
and critically ill patients
factors for this emergency, and opined that the only can localise the site of the aspirated object in some, and among persons at
effective means of treatment was on the scene trache- but not all cases. the extremes of life.
otomy (2). Aspiration events are
In a recent Australian retrospective study of aut- typically attributable to:
Pearl no. 3 (i) the loss of protective
opsy files from 1993 to 2002, 44 cases of food
airway reflexes in the
´
asphyxiation/cafe coronary were identified. Fifty- setting of altered
seven per cent of victims were between 71 and Aspiration in adults is attributable to two consciousness and/or;
90 years of age. Deaths occurred in nursing homes factors: (i) loss of protective reflexes in the (ii) swallowing
(N ¼ 22), at home (N ¼ 11) and in restaurants setting of altered consciousness; and (ii) dysfunction. Mechanical
obstruction of a large
(N ¼ 4). Twenty-seven of the victims (61%) had his- impaired neuromuscular function
airway caused by
tories of neurological or psychiatric disorders such as Altered consciousness resulting in diminished pro- aspiration of a solid
dementia, schizophrenia, Alzheimer’s and Parkinson tective airway reflexes is common in the elderly (10). object can be a
disease. Twenty-seven cases (61%) were edentulous Factors that contribute to altered sensorium include catastrophic event
or had significant numbers of teeth missing. Toxico- dementia, sedating prescription drugs, illicit drugs, requiring emergent
intervention. Aspiration
logical evaluation of blood revealed alcohol and a alcohol use, metabolic disorders, stroke, traumatic
pneumonitis is a non-
variety of psychotropic prescription medications in brain injury and seizures. Other risk factors for aspir- infectious inflammatory
19 cases (3). In another recent autopsy-based, retro- ation include dependence on custodial care for feed- condition, often self-
spective study conducted in Austria, there was signi- ing, dependence for oral care, number of decayed limited, that does not
ficantly higher food-related asphyxiation in the teeth, tube feeding, more than one medical diagnosis, require antimicrobial
therapy, but may result
elderly (age > 64 years) related to semi-solid foods number of medications and smoking (11). Important
in mild to severe
and impaired dentition. This was in contrast to the oesophageal diseases that may cause dysphagia and respiratory dysfunction,
younger individuals (adults aged 64 years or increase the risk for aspiration include collagen vas- including respiratory
younger) who choked significantly more often on cular disorders, cancer, achalasia, oesophageal dys- failure. Aspiration
large pieces of solid food and, on average, had a motility, hiatal hernia, gastroesophageal reflux and pneumonia requires
empiric antimicrobial
higher blood alcohol concentration (4). gastroparesis.
treatment for Gram-
Other risk factors for aspiration include invasive negative bacilli and
diagnostic and therapeutic procedures involving the Gram-positive cocci.
Pearl no. 2
oesophagus or upper thorax; i.e. laryngeal or oeso- Recent reports suggest
phageal cancer resection, neck or thoracic radiation that aerobic bacteria are
a more common cause
Management of catastrophic foreign body for head, neck, lung, breast and mediastinal
of aspiration pneumonia
aspiration requires emergent clearance of the tumours, and gastric cancers with new anastamosis. than anaerobic
airway that may include the Heimlich Aspiration is also associated with mechanical inter- infections. A spectrum
manoeuvre or extraction of the foreign body ruption of glottic closure or the cardiac sphincter of interventions show
by bronchoscopy because of tracheostomy and endotracheal tubes. some promise in
reducing aspiration
Complete obstruction of the trachea is life threaten- Aspiration may result from procedures such as
events in high-risk
ing. If airway patency is not restored within bronchoscopy, upper gastrointestinal endoscopy, individuals.
3–5 min, death or irreversible ischaemic damage to and nasogastric tube insertion and feeding. It is
the heart, brain and other vital organs will result. therefore important that the above-mentioned pro-
The Heimlich manoeuvre is an easily performed pro- cedures be performed by, or under the supervision
cedure that can be lifesaving. An illustrated descrip- of, experienced clinicians. Some risks factors for
tion of the technique may be found on the ref. (5). aspiration in the intensive care unit (ICU) include
In the case of partial airway obstruction, more endotracheal intubation, feeding the patient in the
time is available to transport the patient for appro- recumbent position, gastric and intestinal dysmotil-
priate hospital-based care. Treatment options include ity related to critical illness or postsurgical causes,
extraction of the foreign body with either a flexible large volume tube feedings and feeding gastrostomy
fibreoptic or a rigid bronchoscope. Success rates are tubes (12–19). Patients with any of the aforemen-
higher with rigid bronchoscopy and with an experi- tioned characteristics and/or illnesses should be
enced operator (6–9). Flexible bronchoscopy can be viewed as having a high risk for aspiration. Man-
carried out on an awake, spontaneously ventilating agement strategies should aim to reduce the risk
ª 2007 The Authors
Journal compilation ª 2007 Blackwell Publishing Ltd Int J Clin Pract, May 2007, 61, 5, 846–852

3. 848 Aspiration syndromes
for a major aspiration event in these high-risk signs and symptoms of lower respiratory tract infec-
populations (for additional details, see Pearl no. tion into aspiration pneumonitis, aspiration event,
9). pneumonia and bronchitis based on whether patients
had a witnessed aspiration event and radiographic
absence vs. presence of an infiltrate (unilateral/bilat-
Pearl no. 4
eral, dependent lung zones). The authors defined
aspiration pneumonitis as a patient presenting with
Aspiration pneumonitis is a non-infectious signs and symptoms of lower respiratory tract infec-
inflammatory response to aspiration that may tion of < 24 h duration and a positive chest X ray.
cause mild to severe respiratory dysfunction, The authors tested their management algorithm pro-
but does not require antimicrobial therapy spectively (26). The investigators concluded that it is
Aspiration pneumonitis, also referred to as chemical appropriate to observe patients with an aspiration
pneumonitis, is an inflammatory response typically event or aspiration pneumonitis with symptom dur-
caused by aspiration of gastric acid, but may also ation of < 24 h without initiation of antibiotics.
occur with aspiration of milk products, mineral oils, They speculate that this approach may lead to
acids, fat or other fluids. The resulting injury from shorter hospital stays, lessen chances of adverse
the acidic or alkaline agent damages the bronchial events and delay the development of antibiotic resis-
and alveolar surface epithelial cell lining (20–22). tance patterns highly relevant in an institutionalised
Experimental data from rats demonstrated a biphasic debilitated patient. Antibiotics should however be
pattern of injury following aspiration of acidic con- instituted if the patient’s clinical status deteriorates
tents, the initial phase within 1 h thought to be due needing higher level of monitoring, if the patient fails
to the physiochemical reaction to the acidic aspirate, to improve despite symptomatic treatment, or the
and the second phase within the next 2–3 h thought development of a pulmonary opacity on radiological
to be due to neutrophils resulting in an inflamma- imaging suggestive of pneumonia.
tory reaction (23). This results in atelectasis, release
of inflammatory cytokines and migration of poly-
Pearl no. 5
morphonuclear cells, alveolar macrophages and dis-
ruption of the normal alveolar–capillary membrane.
Patients maybe asymptomatic or may present with Aspiration pneumonia is a common cause of
abrupt onset of dyspnoea, low-grade fever, bilateral respiratory morbidity and mortality in elderly
rales and bilateral infiltrates on the chest radiograph. and debilitated patients
Respiratory injury may be mild to severe and can Aspiration pneumonia accounts for approximately
progress to non-cardiogenic pulmonary oedema, 10% of community-acquired pneumonia. Studies
hypoxemia and respiratory failure. have also suggested an aspiration pneumonia inci-
Initial management and treatment includes careful dence of approximately 30% in the nursing home
monitoring of oxygenation and ventilation for at population (24,27,28). Clinical manifestations include
least 8–12 h after presentation while ensuring that altered mental status, dyspnoea, low blood pressure,
the patient is not given any food (or medicine that tachypnoea, dyspnoea, fever and elevated white count
needs to be swallowed). The patient’s symptoms and without a definite focus of infection. Physical exam-
clinical condition should dictate the initial level of ination findings include poor dentition, coarse rales
monitoring. Aggressive airway clearance with oro- or rhonchi in the lower lung fields, and hypoxemia.
pharyngeal and tracheal suctioning (with an oral or The chest radiograph on initial presentation may be
nasopharyngeal suction catheter) should be per- normal or may show airspace opacities in the
formed, as indicated. If the patient’s clinical condi- dependent lung zones. This commonly progresses to
tion deteriorates as seen by either hypoxemia or airspace consolidation, and may progress to the acute
hypercapnia on an arterial blood gas, respiratory respiratory distress syndrome.
support should be provided with non-invasive or Microscopic examination of sputum commonly
invasive ventilation. The absence of purulent secre- shows many polymorphonuclear cells with Gram-
tions, fever and leucocytosis suggests a non-infectious negative rods and Gram-positive cocci. Sputum cul-
syndrome and, in the setting of mild respiratory tures usually show a predominance of aerobic
insufficiency and limited clinical–radiographic find- Gram-negative enteric bacteria such as Escherichia
ings, supports a management plan of watchful wait- coli, Klebsiella, Serratia, Proteus and Pseudomonal
ing without antimicrobial therapy (24). species, followed less commonly by aerobic Gram-
Mylotte et al. (25,26) have shown that it is poss- positive bacteria such as Staphylococcus, Hemophilus
ible to stratify nursing home patients presenting with and Streptococcal species. Recent analyses show that
ª 2007 The Authors
Journal compilation ª 2007 Blackwell Publishing Ltd Int J Clin Pract, May 2007, 61, 5, 846–852

4. Aspiration syndromes 849
anaerobic bacteria such as Bacteroides, Prevotella, lung because of the almost straight axis between the
Fusobacterium and Peptostreptococcus are rarely trachea and the right main stem bronchus. The most
found in cultures (24,29). Klebsiella species has been common lobes involved include the superior segment
commonly implicated as a cause of pneumonia in of the right lower lobe and the posterior segment of
alcoholics (30). A study that examined pharyngeal the right upper lobe, because of the dependency of
flora of ambulatory alcoholic patients, 59% of the these lobes in the supine position. However, aspiration
alcoholic patients had Gram-negative bacilli in their can occur into any part of the lung depending on the
pharyngeal flora, compared with 14% in the control position of the patient at the time of the inciting event.
group. Seventy-six per cent of the isolates belonged Chest radiographs usually lag a few days behind
to the Klebsiella–Enterobacter group, Klebsiella pneu- the inciting event and the initiation of injury, there-
moniae being the most frequent isolate (40%) (31). fore patients may present immediately after the event
Alcohol causes molecular changes within the lung with a normal chest radiograph. However, in aspir-
that predispose alcoholic patients to pneumonia ation pneumonitis, radiographic opacities may
because of this organism (30,32). resolve rapidly if precipitating factors are controlled.
This is in contrast to the radiographic opacities asso-
ciated with aspiration pneumonia which can take
Pearl no. 6
weeks to resolve.
Chest radiographs in aspiration syndromes
Pearl no. 7
show characteristic, but non-specific
abnormalities
The radiological picture after aspiration of the foreign Antibiotic coverage of Gram-negative bacilli
body depends upon the density of the aspirated object. and Gram-positive cocci are indicated in the
Solids such as metallic nails, coins, and toys, peanuts, treatment of aspiration pneumonia
bones can be visualised on X rays, however soft objects As most causes of aspiration pneumonia are caused
such as meat, vegetables are difficult to visualise. by aspiration of oral or upper gastrointestinal tract
Obstruction of the involved airway presents as either flora, the lungs are exposed to aerobic as well as
as atelectasis or hyperinflation of the lung distal to the anaerobic polymicrobes. Important predisposing fac-
area of blockage. In a study of lung volume, dynamic tors include periodontal disease and gingivitis, alco-
lung compliance and blood gases during the first three holism, prolonged hospitalisation and nursing home
postnatal days in infants with meconium aspiration patients. The usual presentation consists of older age
syndrome, six of the 12 infants with aspiration had patients with moderate grade temperature, leucocyto-
radiological evidence of hyperinflation, while in sis and weight loss associated with cough with puru-
another retrospective study of 150 infants who lent sputum, and dyspnoea. The disease severity can
presented with wheezing and radiological hyperinfla- vary from a segmental pneumonia to lung abscess to
tion, 40% were found to have meconium aspiration empyema. Aerobic Gram-negative enteric bacteria
(33,34). such as E. coli, Klebsiella, Serratia, Proteus, Pseudo-
In a recent series of children with suspected monas and aerobic Gram-positive bacteria such as
foreign body aspiration, virtual bronchoscopy and Staphylococcus, Hemophilus and Streptococcus are
low-dose multidetector computed tomography were commonly grown in sputum cultures from these
shown to be effective diagnostic imaging modalities. patients. Anaerobic bacteria such as Bacteroides,
Obstructive pathology was found in 16 (43%) of 37 Prevotella, Fusobacterium and Peptostreptococcus are
patients using these imaging techniques. In 13 of found much less commonly.
these patients, foreign bodies were detected and The antibiotics that have traditionally been used
removed via conventional bronchoscopy. In 21 include piperacillin–tazobactam, penicillins with met-
patients in whom no obstructive pathology was ronidazole, clindamycin, imipenem for 2–6 weeks
detected by virtual bronchoscopy and computed depending upon the severity of the underlying dis-
tomography, conventional bronchoscopy was not ease (10,24,29). However, the rationale behind their
performed. These patients were followed for use has been the provision of anaerobic coverage.
5–-20 months without any recurrent obstructive Given the more recent data on the higher prevalence
symptomatology (35). of aerobic bacteria in patients with aspiration pneu-
The most common radiographic finding of aspir- monia, more studies are needed to establish the cor-
ation pneumonitis and pneumonia is patchy bilateral rect antibiotic regimens that treat the underlying
airspace consolidation with a perihilar or basilar distri- infection, minimise multidrug resistance patterns and
bution. Aspiration commonly occurs into the right establish cost-effectiveness.
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Journal compilation ª 2007 Blackwell Publishing Ltd Int J Clin Pract, May 2007, 61, 5, 846–852

5. 850 Aspiration syndromes
There has been a significant interest in preventing
Pearl no. 8
aspiration in the critically ill population, especially
mechanically ventilated patients, with ongoing clin-
Bedside evaluation and imaging techniques can ical research in this area. Interventions that have
be utilised to assess the risk of aspiration shown promising in preventing or reducing aspir-
Attempting to feed patients with definite risk factors ation in the critically ill patients, but have not been
for aspiration without a complete safety evaluation proven in large multicentre prospective clinical trials,
exposes them to serious and avoidable risks (10). All include (10,12,17,22,24,39–52):
patients suspected of having any risk factor must • a chin down position while feeding patients with
undergo a thorough evaluation before feeding is altered swallowing ability (39);
attempted. This includes a complete neurological • percutaneous endoscopic gastrostomy tube or per-
evaluation with assessment of cortical functions, cutaneous endoscopic jejunostomy tube for feeding
assessment of bulbar muscles, gag and cough reflex, in chronically debilitated patients (10,39);
presence of dentition and dental hygiene. If any • feeding by hand compared with insertion of feed-
doubt persists, then a formal swallow evaluation gen- ing tube in the geriatric population (10,39);
erally performed by a speech pathologist should be • soft mechanical diet and thickened liquids (39);
requested. Details about the performance of a swal- • suction of subglottic secretions in the mechanically
low evaluation may be found on ref. (36). ventilated patient (42,43);
Flexible endoscopic evaluation of swallowing with • gastric acid suppression by drugs (12,44–47);
or without sensory testing can usually be performed • minimise use of sedating drugs (10,48,49);
at the bedside with an initial assessment of cough • use of amantadine, angiotensin converting enzyme
after swallowing water or a thick liquid. Speech inhibitors and cilostazol (10,39,48,49);
pathologists then use a flexible fibreoptic scope to • monitoring gastric residual volumes as a marker of
detect the presence of food in the posterior pha- aspiration risk (50);
rynx, vallecula, over the vocal cords, along with • placement of a postpyloric feeding tube
assessment of vocal cord function. Modified barium (10,12,17,24,39,51,52).
swallow is another kind of study that involves
directing the patient to swallow barium under fluo-
Pearl no. 10
roscopic imaging. Any passage or retention of this
radio-opaque substance in the respiratory tract can
be directly seen. Aspiration events are a common cause of
morbidity and mortality among debilitated,
terminally ill, and elderly patients, especially
Pearl no. 9
when enteral artificial nutrition or hydration is
administered. Challenging ethical dilemmas
Simple interventions show some promise in often arise in this clinical context
reducing aspiration events in high-risk In a recent Canadian prospective cohort study that
individuals looked at 1946 adults admitted with pneumonia,
Patients at increased risk of aspiration include those 10% of those with community-acquired pneumonia
who have absent or diminished protective airway had aspirated, compared with 30% of those with
reflexes as may occur in the setting of altered con- continuing care facility-acquired pneumonia (27).
sciousness or impaired neuromuscular function (for Patients with aspiration pneumonia were younger,
additional details, see Pearl no. 3). more likely to go to ICU, to require mechanical ven-
There is some evidence that keeping the head of tilation and had a longer length of stay and a higher
the patient’s bed higher than 30–45° reduces the mortality rate than those with non-aspiration-related
incidence of nosocomial pneumonia caused by aspir- pneumonia. The mortality rate in the community
ation, especially in the critically ill or mechanically was 19% for aspiration pneumonia vs. 7% for non-
ventilated patients (12,17,37–39). All patients in the aspiration pneumonia. In the continuing care facility
hospital with risk factors for aspiration should have patients, the mortality rate was 28% for aspiration
the head of their bed raised unless contraindicated. pneumonia vs. 15% for non-aspiration pneumonia.
Oral decontamination with antiseptic solutions (2% The predominant risks factors for those with com-
chlorhexidine with and without colistin) in mechan- munity-acquired aspiration pneumonia were
ically ventilated patient has recently been shown to impaired consciousness because of alcohol, drugs or
be beneficial in preventing ventilator associated hepatic failure; 72% of continuing care facility
pneumonia (12,40,41). patients with aspiration pneumonia had neurological
ª 2007 The Authors
Journal compilation ª 2007 Blackwell Publishing Ltd Int J Clin Pract, May 2007, 61, 5, 846–852

6. Aspiration syndromes 851
disease that resulted in dysphagia. As highlighted in References
the last pearl, a spectrum of simple intervention have
1 Centers for Disease Control and Prevention (CDC). Nonfatal cho-
shown some promise in reducing the incidence of king-related episodes among children – United States, 2001.
aspiration in the at risk population, however no sin- MMWR Morb Mortal Wkly Rep 2002; 51: 945–8.
gle intervention or combination of interventions has ´
2 Haugen RK. The cafe coronary: sudden deaths in restaurants.
´
JAMA 1963; 186: 142–3 (The original JAMA cafe coronary paper).
been proven in large prospective randomised trials to ´
3 Wick R, Gilbert JD, Byard RW. Cafe coronary syndrome – fatal
eliminate this hazard. The involved physician must choking on food: an autopsy approach. J Clin Forensic Med 2006;
weigh all these risks with the anticipated benefits of 13: 135–8 (Epub 13 December 2005).
attempting to feed chronically debilitated patients, 4 Berzlanovich AM, Fazeny-Dorner B, Waldhoer T, Fasching P. For-
eign body asphyxia: a preventable cause of death in the elderly.
have informed discussions with the patient or the Am J Prev Med 2005; 28: 65–9.
family explaining these not so trivial ethical issues, 5 The Heimlich Institute. How to Do the Heimlich Maneuver. http://
and then making appropriate decisions. The physi- www.heimlichinstitute.org/page.php?id=34 (accessed 23 March
cian must therefore use his clinical judgment, by 2007).
6 Soysal O, Kuzucu A, Ulutas H. Tracheobronchial foreign body
identifying patients at risk for aspiration (Pearl no. aspiration: a continuing challenge. Otolaryngol Head Neck Surg
3), performing appropriate tests with the assistance 2006; 135: 223–6.
of speech pathologists and radiologists (and physical 7 Ibrahim Sersar S, Hamza UA, AbdelHameed WA, AbulMaaty RA.
Inhaled foreign bodies: management according to early or late
therapy if needed) when in doubt (Pearl no. 8), not
presentation. Eur J Cardiothorac Surg 2005; 28: 369–74.
allowing at risk patients to be fed enterally without 8 Rafanan AL, Mehta AC. Adult airway foreign body removal.
supervision, and when enteral feeding is considered What’s new? Clin Chest Med 2001; 22: 319–30.
appropriate, using a variety of techniques to prevent 9 Baharloo F, Veyckemans F, Francis C et al. Tracheobronchial for-
eign bodies: presentation and management in children and adults.
aspiration (Pearl no. 9).
Chest 1999; 115: 1357–62.
In recent years there has been debate about the 10 Marik PE, Kaplan D. Aspiration pneumonia and dysphagia in the
artificial feeding of terminally ill patients, as it has elderly. Chest 2003; 124: 328–36.
been shown that withholding feeding often does not 11 Langmore SE, Terpenning MS, Schork A et al. Predictors of aspir-
ation pneumonia: how important is dysphagia? Dysphagia 1998;
contribute to the pain or suffering of these patients 13: 69–81.
(53–57). There is also a significant population of 12 Tablan OC, Anderson LJ, Besser R et al. Guidelines for preventing
patients that have developed severe neurological health-care-associated pneumonia, 2003: recommendations of the
and/or psychiatric disability which puts them at risk CDC and the Healthcare Infection Control Practices Advisory
Committee. Healthcare Infection Control Practices Advisory
for repeated episodes of aspiration and associated Committee; Centers for Disease Control and Prevention (U.S.).
lung disease. Given the lack of any definitive inter- MMWR Recomm Rep 2004; 53: 1–36 and also Respir Care 2004;
vention to prevent aspiration (short of not feeding 49: 926–39.
patients or administering total parenteral nutrition) 13 Sherman JM, Davis S, Albamonte-Petrick S et al. Care of the child
with a chronic tracheostomy. This official statement of the Ameri-
some healthcare professionals believe that the prac- can Thoracic Society was adopted by the ATS Board of Directors,
tice of feeding this population either through the July 1999. Am J Respir Crit Care Med 2000; 161: 297–308.
mouth, nasogastric tubes or percutaneous gastrosto- 14 Eisen GM, Baron TH, Dominitz JA et al. Complications of upper
GI endoscopy. Gastrointest Endosc 2002; 55: 784–93.
my/jejunostomy tubes puts them at continuous risk
15 Mehta AC, Prakash UB, Garland R et al. American College of
for aspiration, increased morbidity and should there- Chest Physicians and American Association for Bronchology [cor-
fore not be pursued. Decisions about whether feed- rected] consensus statement: prevention of flexible bronchoscopy-
ing these patients improves quality of life must be associated infection. Chest 2005; 128: 1742–55.
16 ECC Committee, Subcommittees and Task Forces of the American
the result of a dialogue among patients, if they pos-
Heart Association. 2005 American Heart Association Guidelines
sess decisional capacity, healthcare surrogate decision for Cardiopulmonary Resuscitation and Emergency Cardiovascular
makers for patients who lack decisional capacity, Care. Circulation 2005; 112S: IV1–203.
and healthcare providers. Every case needs to be 17 Heyland DK, Dhaliwal R, Drover JW et al. Canadian clinical prac-
tice guidelines for nutrition support in mechanically ventilated,
addressed on an individual basis, taking into account critically ill adult patients. JPEN J Parenter Enteral Nutr 2003; 27:
the wishes of the patient if stated (directly, by family 355–73.
or as an advanced directive), the current health 18 American Society of Anesthesiologists Task Force on Management
status of the patient including long-term prognosis, of the Difficult Airway. Practice guidelines for management of the
difficult airway: an updated report by the American Society of
and the risks, benefits, and alternatives to artificial Anesthesiologists Task Force on Management of the Difficult
enteral feeding as communicated by healthcare Airway. Anesthesiology 2003; 98: 1269–77.
providers. 19 McClave SA, Lukan JK, Stefater JA et al. Poor validity of residual
volumes as a marker for risk of aspiration in critically ill patients.
Crit Care Med 2005; 33: 324–30.
Acknowledgements 20 Madjdpour L, Kneller S, Booy C et al. Acid-induced lung
injury: role of nuclear factor-kappaB. Anesthesiology 2003; 99:
None. 1323–32.
ª 2007 The Authors
Journal compilation ª 2007 Blackwell Publishing Ltd Int J Clin Pract, May 2007, 61, 5, 846–852

7. 852 Aspiration syndromes
21 Vuichard D, Ganter MT, Schimmer RC et al. Hypoxia aggravates 39 Loeb MB, Becker M, Eady A, Walker-Dilks C. Interventions to
lipopolysaccharide-induced lung injury. Clin Exp Immunol 2005; prevent aspiration pneumonia in older adults: a systematic review.
141: 248–60. J Am Geriatr Soc 2003; 51: 1018–22.
22 Beck-Schimmer B, Rosenberger DS, Neff SB et al. Pulmonary 40 Koeman M, van der Ven AJ, Hak E et al. Oral decontamination
aspiration: new therapeutic approaches in the experimental model. with chlorhexidine reduces the incidence of ventilator-associated
Anesthesiology 2005; 103: 556–66. pneumonia. Am J Respir Crit Care Med 2006; 173: 1348–55 and
23 Kennedy TP, Johnson KJ, Kunkel RG et al. Acute acid aspiration also in ACP J Club 2006; 145: 68.
lung injury in the rat: biphasic pathogenesis. Anesth Analg 1989; 41 Pineda LA, Saliba RG, El Solh AA. Effect of oral decontamination
69: 87–92. with chlorhexidine on the incidence of nosocomial pneumonia:
24 Marik PE. Aspiration pneumonitis and aspiration pneumonia. N a meta-analysis. Crit Care 2006; 10: R35. http://ccforum.com/
Engl J Med 2001; 344: 665–71. content/10/1/R35 (accessed 23 March 2007).
25 Mylotte JM, Goodnough S, Naughton BJ. Pneumonia versus aspir- 42 Kollef MH, Skubas NJ, Sundt TM. A randomized clinical trial of
ation pneumonitis in nursing home residents: diagnosis and man- continuous aspiration of subglottic secretions in cardiac surgery
agement. J Am Geriatr Soc 2003; 51: 1–7. patients. Chest 1999; 116: 1339–46.
26 Mylotte JM, Goodnough S, Gould M. Pneumonia versus aspiration 43 Kees Smulders M, van der Hoeven H, Weers-Pothoff I, Van-
pneumonitis in nursing home residents: prospective application of denbroucke-Grauls C. A randomized clinical trial of intermittent
a clinical algorithm. J Am Geriatr Soc 2005; 53: 755–61. subglottic secretion drainage in patients receiving mechanical ven-
27 Reza Shariatzadeh M, Huang JQ, Marrie TJ. Differences in the fea- tilation. Chest 2002; 121: 858–62.
tures of aspiration pneumonia according to site of acquisition: 44 Laheij RJ, Sturkenboom MC, Hassing RJ et al. Risk of community-
community or continuing care facility. J Am Geriatr Soc 2006; 54: acquired pneumonia and use of gastric acid-suppressive drugs.
296–302. JAMA 2004; 292: 1955–60.
` ´
28 Fernandez-Sabe N, Carratala J, Roson B et al. Community- 45 Messori A, Trippoli S, Vaiani M et al. Bleeding and pneumonia in
acquired pneumonia in very elderly patients: causative organisms, intensive care patients given ranitidine and sucralfate for preven-
clinical characteristics, and outcomes. Medicine (Baltimore) 2003; tion of stress ulcer: meta-analysis of randomised controlled trials.
82: 159–69. BMJ 2000; 321: 1–7.
29 El-Solh AA, Pietrantoni C, Bhat A et al. Microbiology of severe 46 Canani RB, Cirillo P, Roggero P et al. Therapy with gastric acidity
aspiration pneumonia in institutionalized elderly. Am J Respir Crit inhibitors increases the risk of acute gastroenteritis and community-
Care Med 2003; 167: 1650–4. acquired pneumonia in children. Pediatrics 2006; 117: e817–20.
30 Happel KI, Nelson S. Alcohol, immunosuppression, and the lung. 47 CAG Clinical Affairs Committee. Community-acquired pneumonia
Proc Am Thorac Soc 2005; 2: 428–32. and acid-suppressive drugs: position statement. Can J Gastroenterol
31 Fuxench-Lopez Z, Ramirez-Ronda CH. Pharyngeal flora in ambu- 2006; 20: 123–5.
latory alcoholic patients: prevalence of gram-negative bacilli. Arch 48 Ohrui T. Preventative strategies for aspiration pneumonia in
Intern Med 1978; 138: 1815–6. elderly disabled persons. Tohoku J Exp Med 2005; 207: 3–12.
32 Happel KI, Odden AR, Zhang P et al. Acute alcohol intoxication 49 Yamaya M, Yanai M, Ohrui T et al. Interventions to prevent pneu-
suppresses the interleukin 23 response to Klebsiella pneumoniae monia among older adults. J Am Geriatr Soc 2001; 49: 85–90.
infection. Alcohol Clin Exp Res 2006; 30: 1200–7. 50 McClave SA, Lukan JK, Stefater JA et al. Poor validity of residual
33 Yeh TF, Lilien LD, Barathi A, Pildes RS. Lung volume, dynamic volumes as a marker for risk of aspiration in critically ill patients.
lung compliance, and blood gases during the first 3 days of post- Crit Care Med 2005; 33: 324–30.
natal life in infants with meconium aspiration syndrome. Crit Care 51 Heyland DK, Drover JW, MacDonald S et al. Effect of postpyloric
Med 1982; 10: 588–92. feeding on gastroesophageal regurgitation and pulmonary microas-
34 Gupta AK, Shashi S, Lamba IM, Anand NK. Do insults to the piration: results of a randomized controlled trial. Crit Care Med
developing lung increase the incidence of wheezing in infants. 2001; 29: 1495–501.
J Trop Pediatr 1994; 40: 29–31. 52 Kreymann KG, Berger MM, Deutz NE et al. ESPEN Guidelines on
35 Adaletli I, Kurugoglu S, Ulus S et al. Utilization of low-dose multi- Enteral Nutrition: intensive care. Clin Nutr 2006; 25: 210–23.
detector CT and virtual bronchoscopy in children with suspected 53 Volkert D, Berner YN, Berry E et al. ESPEN Guidelines on Enteral
foreign body aspiration. Pediatr Radiol 2007; 37: 33–40 (Epub 11 Nutrition: geriatrics. Clin Nutr 2006; 25: 330–60.
Oct 2006 ). 54 Slomka J. Withholding nutrition at the end of life: clinical and
36 Voice and Swallowing Center, College of Physicians and Surgeons, ethical issues. Cleve Clin J Med 2003; 70: 548–52.
Columbia University at New York Presbyterian Hospital. Candi- 55 Gillick MR. Rethinking the role of tube feeding in patients with
dates for a Swallowing Evaluation. http://voiceandswallowing.com/ advanced dementia. N Engl J Med 2000; 342: 206–10.
swall_caneval.htm (accessed 23 March 2007). 56 Finucane TE, Christmas C, Travis K. Tube feeding in patients with
37 Drakulovic MB, Torres A, Bauer TT et al. Supine body position as advanced dementia: a review of the evidence. JAMA 1999; 282:
a risk factor for nosocomial pneumonia in mechanically ventilated 1365–70.
patients: a randomised trial. Lancet 1999; 354: 1851–8. 57 Casarett D, Kapo J, Caplan A. Appropriate use of artificial nutri-
38 Van Nieuwenhoven CA, Vandenbroucke-Grauls C, van Tiel FH tion and hydration – fundamental principles and recommenda-
et al. Feasibility and effects of the semirecumbent position to pre- tions. N Engl J Med 2005; 353: 2607–12.
vent ventilator-associated pneumonia: a randomized study. Crit
Care Med 2006; 34: 396–402. Paper received December 2006, accepted January 2007
ª 2007 The Authors
Journal compilation ª 2007 Blackwell Publishing Ltd Int J Clin Pract, May 2007, 61, 5, 846–852