• Foreign body aspiration can be a life-threatening emergency
• An aspirated solid or semisolid object may lodge in the larynx or trachea
• If the object is large enough to cause nearly complete obstruction of the airway, asphyxia
may rapidly cause death.
• Lesser degrees of obstruction or passage of the obstructive object beyond the carina can
result in less severe signs and symptoms.
• Chronic debilitating symptoms with recurrent infections might occur with delayed
extraction or the patient may remain asymptomatic.
• The actual aspiration event can usually be identified although it is often not immediately
appreciated.
• The aspirated object might even escape detection.
• Most often the aspirated object is food but a broad spectrum of aspirated items has been
documented over the years.
• Commonly retrieved objects include:
Seeds
Nuts
Bone fragments
Nails
Small toys
Coins, pins
Medical instrument fragments and
Dental appliances
• Geographic differences in the spectrum of objects commonly found in a particular
environment and variations in dietary and eating habits affect the relative frequency with
which various objects are aspirated.
Pathophysiology
• Near-total obstruction of the larynx or trachea can cause immediate asphyxia and death.
• Should the object pass beyond the carina, its location would depend on the patient's age
and physical position at the time of the aspiration.
• Because the angles made by the main stem bronchi with the trachea are identical until age
of 15 years, foreign bodies are found on either side with equal frequency in persons in
this age group.
• With normal growth and development, the adult right and left mainstem bronchi diverge
from the trachea with very different angles, with the right main stem bronchus being more
acute and therefore making a relatively straight path from larynx to bronchus.
• Objects that descend beyond the trachea are more often found in the right endobronchial
tree than in the left.
• Cough, wheeze, stridor, dyspnea, cyanosis, and even asphyxia might ensue.
• Organic foreign bodies such as oily nuts (commonly peanuts) induce inflammation and
Oedema.
• Local inflammation, Oedema, cellular infiltration, ulceration, and granulation tissue
formation may contribute to airway obstruction while making bronchoscopic
identification and removal of the object more difficult.
• The airway becomes more likely to bleed with manipulation and the object becomes more
likely obscured and more difficult to dislodge.
• Mediastinitis or tracheoesophageal fistulas may result.
• Distal to the obstruction air trapping may occurs leading to local
Emphysema
Atelectasis
Hypoxic vasoconstriction
Post obstructive pneumonia and the
Possibility of volume loss
Necrotizing pneumonia or abscess
Suppurative pneumonia, or bronchiectasis
• Bronchoscopically, the object may appear as a tumor.
• Even if the object is removed, the inflammatory changes may not be completely
reversible.
• Some investigators believe scar carcinoma may develop over time.
• The likelihood of complications increases after 24-48 hours making expeditious removal
of the foreign body imperative.
• Speaking while eating increases the likelihood of food aspiration.
• Impaired consciousness also increases the likelihood of aspiration while eating.
Causes
• Children are at risk for putting small toys, candies, or nuts into their mouths.
• Children aged 1-3 years chew incompletely with incisors before their molars erupt, and
objects or fragments may be propelled posteriorly, triggering a reflex inhalation
• Among adults, the following conditions, actions, and procedures facilitate foreign body
aspiration
Impaired swallowing reflex
Impaired cough reflex
Mental retardation
Alcohol or sedative use
General anesthesia
Poor dentition
Dental, pharyngeal, or airway procedures
Altered sensorium
Loss of consciousness
Convulsions
Maxillofacial trauma
• Frequently aspirated objects include food such as nuts and seeds, teeth, dental appliances
and medical instruments.
• The original event might have been forgotten.
• Choking with severe dyspnea leading to respiratory or cardiac arrest while eating might
be initially misdiagnosed as myocardial ischemia.
Epidemiology
• The often-fatal syndrome of acute asphyxia from upper airway obstruction associated
with eating (acute asphyxia), and aspiration of gastric contents are usually not considered
with other foreign body aspiration syndromes.
• For these reasons, the true incidence and prevalence of foreign body aspiration is
unknown.
• The overall risk of death from acute asphyxia is estimated to be 0.66 deaths per 100,000
people.
• Morbidity increases if extraction of the object is delayed beyond 24 hours.
• The male-to-female ratio is 2:1.
• Children especially those aged 1-3 years are at risk for foreign body aspiration because of
their tendency to put everything in their mouths and because of the way they chew.
• Young children chew their food incompletely with incisors before their molars erupt.
• Objects or fragments may be propelled posteriorly triggering a reflex inhalation.
• Adults are at increased risk of aspirating foreign bodies enduring oropharyngeal
procedures as they are sedated.
Clinical Features
• History
In the acute asphyxia a large object (often poorly chewed meat) lodges in the larynx
or trachea causing nearly complete airway obstruction.
Respiratory distress, aphonia, cyanosis, loss of consciousness, and death occur in
quick succession unless the object is dislodged.
When the degree of obstruction is less severe or when the aspirated object descends
beyond the carina, the presentation is less dramatic.
Sudden onset of the classic triad of coughing, wheezing and decreased breathing
sounds is frequently not observed.
Presenting symptoms other than cough include
Fever (although this might be uncommon in early stage)
Hemoptysis
Dyspnea and
Chest pain
• A history of a choking episode is not always obtained or may have initially been ignored
or misdiagnosed
• Most patients or parents can identify a specific episode of choking, however presentation
is often delayed by more than a week.
• The latency period prior to the onset of symptoms may last months or years if the foreign
body is inert bone or inorganic material.
• Patients may have been empirically treated for other conditions even when a choking
episode was witnessed.
• Patients with chronic symptoms may have been erroneously diagnosed as having asthma
or chronic bronchitis.
• Young children and patients with neurologic or psychiatric disorders are at increased risk
for aspiration but might not be able to describe symptoms or to report choking episodes
• Other risk factors include
Institutionalization
Old age
Abnormal dentition
Alcohol or sedative use
• A presentation of cyanosis, cough, wheeze, incompletely resolved pneumonia, or
localized bronchiectasis should raise suspicion of foreign body aspiration, particularly in
individuals at risk for foreign body aspiration.
• Seek information about a history of
Impaired swallowing
Impaired coughing
Traumatic loss of consciousness
Intoxication or
Oropharyngeal surgery
Physical Findings
• A small number of foreign body aspirations are incidentally found after chest radiography
or bronchoscopic inspection.
• Patients may be asymptomatic or may be undergoing testing for other diagnoses
• Physical findings may include
Stridor
Wheeze,
Diminished breath sounds
• If obstruction is severe cyanosis may occur
• Signs of consolidation can accompany post obstructive pneumonia
Differential Diagnosis, Investigations and Treatment of Respiratory
Obstruction
Differential Diagnoses of Respiratory Obstruction
• Pneumonia
• Pneumothorax
• Lung Abscess
• Pulmonary Embolism
• Respiratory Failure
• Chronic Obstructive Pulmonary Disease (COPD)
• Emphysema
• Atelectasis
• Myocardial infarction
Investigations
• Investigations for respiratory obstruction cannot be done at primary health care facilities
and therefore patients suspected of having the condition must be referred to hospitals.
The investigations are listed here below.
Chest radiography
CT scanning of the chest
Bronchoscope (both rigid and flexible) can be both diagnostic and therapeutic
Fluoroscopy
Radioisotope lung perfusion scanning
Treatment
Medical Care
• Acute choking, with respiratory failure associated with tracheal or laryngeal foreign body
obstruction, may be successfully treated at the scene with the heimlich maneuver back
blows and abdominal thrusts.
Heimlich Maneuver
• It is an emergency treatment for obstruction of the airway in adults.
• It may be needed when someone chokes on a piece of food that has ‘gone down the
wrong way’.
• To perform the Heimlich maneuver.
Stand behind the victim.
Wrap your arms around their waist.
Make a fist with one hand and hold the fist with the thumb side just below the breast
bone.
Place your other hand over this first and use it to pull sharply into the top of the
choking person's abdomen and forcefully press up into the victim's diaphragm to
expel the obstruction (most commonly food).
Repeat as necessary.
Children and infants need a different approach for the Heimlich maneuver
• Even in non emergency situations expeditious removal of tracheobronchial foreign bodies
is recommended.
Bronchoscopy
Surgical care
Prevention
• In order to prevent food aspiration the diet should be appropriate for the patient's ability
to chew and swallow.
• The size and shape of food bits should be appropriate for the patient's age and the size of
the larynx and tracheobronchial tree.
• Pay attention to the size and texture of foods and objects available to children and adults
with impaired mentation or ability to protect the airway such as impaired chewing,
swallowing or coughing.
• Removal of appliances prior to manipulation of the teeth or airway is essential.
• Note the condition of medical equipment at the beginning and end of procedures
involving the pharynx, larynx, respiratory tract, or digestive tract.
• Sedatives and topical anesthetics increase the risk for aspiration therefore use them
cautiously.
• Children should not be given toys or food substances that they can choke on.
Complications
• The severity of the complications of foreign body aspiration depends on the
Size
Shape
Composition
Location and
Orientation of the aspirated object
• The following complications may ensue
Cough
Dyspnea
Wheeze
Stridor
Hemoptysis
Asphyxia
Laryngeal oedema
Pneumothorax
Pneumomediastinum
Tracheobronchial rupture
Cardiac arrest
Complications of Respiratory Obstruction
• Delay in treatment of respiratory obstruction can result in the following conditions:
Obstructive emphysema
Atelectasis
Tracheoesophageal fistula
Bronchial stricture
Pneumonia
Persistent cough
Hemoptysis
Polyp formation
Localized bronchiectasis
Chronic post obstructive pneumonia
Lung abscess
Bronchopleural fistula
Decreased lung perfusion
Chronic complications may be due to the foreign body itself or to trauma induced
during attempts to remove the object
The complication rate increases if extraction of foreign body is delayed
                                                                                                                       
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