Foreign body aspiration

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Foreign body aspiration
Aspirated corn kernel (3791886968).jpg
Aspiration of corn kernel that became lodged in the airway of an adult patient.
Specialty Respirology
Symptoms Fever, choking, sore throat, drooling, stridor, speech difficulties, cyanosis, bronchitis, coughing, wheezing
Complications Pulmonary aspiration, blockage, pneumonia, respiratory failure, respiratory infection, cardiopulmonary arrest, pulmonary embolism, pulmonary hemorrhage
Usual onsetSudden or gradual
Risk factors Children ages 3 and lower, alcoholism, drug abuse, senility, Parkinson's disease, improper eating habits, chest trauma, neck trauma, Alzheimer's disease
Differential diagnosis Asthma, COPD, lung cancer, poisoning, drug overdose, cyanide poisoning, epileptic seizures, esophageal cancer, laryngeal cancer

Foreign body aspiration occurs when a foreign body enters the airway which can cause difficulty breathing or choking. [1] Objects may reach the respiratory tract and the digestive tract from the mouth and nose, but when an object enters the respiratory tract it is termed aspiration. The foreign body can then become lodged in the trachea or further down the respiratory tract such as in a bronchus. [2] Regardless of the type of object, any aspiration can be a life-threatening situation and requires timely recognition and action to minimize risk of complications. [3] While advances have been made in management of this condition leading to significantly improved clinical outcomes, there were still 2,700 deaths resulting from foreign body aspiration in 2018. [4] Approximately one child dies every five days due to choking on food in the United States, highlighting the need for improvements in education and prevention. [5]

Contents

Signs and symptoms

Basic human airway anatomy. Objects can enter the trachea and lungs via the mouth or nose. Anatomy-31056 1280.png
Basic human airway anatomy. Objects can enter the trachea and lungs via the mouth or nose.

Signs and symptoms of foreign body aspiration vary based on the site of obstruction, the size of the foreign body, and the severity of obstruction. [2] 20% of foreign bodies become lodged in the upper airway, while 80% become lodged in a bronchus. [6] Signs of foreign body aspiration are usually abrupt in onset and can involve coughing, choking, and/or wheezing; however, symptoms can be slower in onset if the foreign body does not cause a large degree of obstruction of the airway. [2] With this said, aspiration can also be asymptomatic on rare occasions. [1]

Classically, patients present with acute onset of choking. [2] In these cases, the obstruction is classified as a partial or complete obstruction. [2] Signs of partial obstruction include choking with drooling, stridor, and the patient maintains the ability to speak. [2] Signs of complete obstruction include choking with inability to speak or absence of bilateral breath sounds among other signs of respiratory distress such as cyanosis. [2] A fever may be present. When this is the case, it is possible the object may be chemically irritating or contaminated. [7]

Foreign bodies above the larynx often present with stridor, while objects below the larynx present with wheezing. [6] Foreign bodies above the vocal cords often present with difficulty and pain with swallowing and excessive drooling. [8] Foreign bodies below the vocal cords often present with pain and difficulty with speaking and breathing. [8] Increased respiratory rate may be the only sign of foreign body aspiration in a child who cannot verbalize or report if they have swallowed a foreign body. [6]

If the foreign body does not cause a large degree of obstruction, patients may present with chronic cough, asymmetrical breath sounds on exam, or recurrent pneumonia of a specific lung lobe. [2] If the aspiration occurred weeks or even months ago, the object may lead to an obstructive pneumonia or even a lung abscess. Therefore, it is important to consider chronic foreign body aspiration in patients whose histories include unexplained recurrent pneumonia or lung abscess with or without fever. [7]

In adults, the right lower lobe of the lung is the most common site of recurrent pneumonia in foreign body aspiration. [2] This is due to the fact that the anatomy of the right main bronchus is wider and steeper than that of the left main bronchus, allowing objects to enter more easily than the left side. [2] Unlike adults, there is only a slight propensity towards objects lodging in the right bronchus in children. [7] This is likely due to the bilateral bronchial angles being symmetric until about 15 years of age when the aortic knob fully develops and displaces the left main bronchus. [7]

Signs and symptoms of foreign body aspiration in adults may also mimic other lung disorders such as asthma, COPD, and lung cancer. [9] {

Causes

Section of larynx showing aspirated fragment of meat (top center). Larynx - Aspiration of a large fragment of meat.jpg
Section of larynx showing aspirated fragment of meat (top center).

Most cases of foreign body aspiration are in children ages 6 months to 3 years due to the tendency for children to place small objects in the mouth and nose. Children of this age usually lack molars and cannot grind up food into small pieces for proper swallowing. [8] Small, round objects including nuts, hard candy, popcorn kernels, beans, and berries are common causes of foreign body aspiration. [2] Latex balloons are also a serious choking hazard in children that can result in death. A latex balloon will conform to the shape of the trachea, blocking the airway and making it difficult to expel with the Heimlich maneuver. [10] In addition, if the foreign body is able to absorb water, such as a bean, seed, or corn, among other things, it may swell over time leading to a more severe obstruction. [4]

In adults, foreign body aspiration is most prevalent in populations with impaired swallowing mechanisms such as the following: neurological disorders, alcohol use, advanced age leading to senility (most common in the 6th decade of life), and loss of consciousness. [11] This inadequate airway protection may also be attributed to poor dentition, seizure, general anesthesia, or sedative drug use. [4]

Chest x-ray of an adult with obstructive pneumonia in the right lung (left side of the image) evidenced by hypodense (less dark) area. This is from a blockage in the respiratory tract leading to an infection distal to the obstruction. Obstructive pneumonia Case 233 (7471755378).jpg
Chest x-ray of an adult with obstructive pneumonia in the right lung (left side of the image) evidenced by hypodense (less dark) area. This is from a blockage in the respiratory tract leading to an infection distal to the obstruction.

Diagnosis

X-ray of focal pneumonia in lower right lung lobe (bottom left of chest in image) due to aspiration and airway obstruction. Aspiration pneumonia201711-3264.jpg
X-ray of focal pneumonia in lower right lung lobe (bottom left of chest in image) due to aspiration and airway obstruction.

The most important aspect of the assessment for a clinician is an accurate history provided by an event witness. [7] Unfortunately, this is not always available.

Physical examination

A physical examination by a clinician should include, at a minimum, a general assessment in addition to cardiac and pulmonary exams. Auscultation of breath sounds may give additional information regarding object location and the degree of airway obstruction. [7] The presence of drooling and dysphagia (drooling) should always be noted alongside the classic signs of airway obstruction as these can indicate involvement of the esophagus and impact management. [12]

Diagnostic Imaging

Foreign body aspiration of a coin in the esophagus. Foreign body aspiration.jpg
Foreign body aspiration of a coin in the esophagus.

Radiography is the most common form of imaging used in the initial assessment of a foreign body presentation. Most patients receive a chest x-ray to determine the location of the foreign body. [2] Lateral neck, chest, and bilateral decubitus end-expiratory chest x-rays should be obtained in patients suspected of having aspirated a foreign body. [6] However, the presence of normal findings on chest radiography should not rule out foreign body aspiration as not all objects can be visualized. [2] In fact, up to 50% of cases can have normal findings on radiography. [7] This is because visibility of an object depends on many factors, such as the object's material, size, anatomic location and surrounding structures, as well as the patient's body habitus. [13] X-ray beams only show an object if that object's composition blocks the rays from traveling through, making it radiopaque and appearing lighter or white on the image. This also requires it to not be stuck behind something that blocks the beams first. [13] Objects that are radiopaque include items made of most metals except aluminum, bones except most fish bones, and glass. If the material does not block the x-ray beams it is considered radiolucent and will appear dark which prevents visualization. [13] This includes material such as most plastics, most fish bones, wood, and most aluminum objects. [13]

Other diagnostic imaging modalities, such as magnetic resonance imaging, computed tomography, and ventilation perfusion scans play a limited role in the diagnosis of foreign body aspiration. [7]

Signs on x-ray that are more commonly seen than the object itself and can be indicative of foreign body aspiration include visualization of the foreign body or hyperinflation of the affected lung. [13] Other x-ray findings that can be seen with foreign body aspiration include obstructive emphysema, atelectasis, and consolidation. [8]

While, x-ray can be used to visualize the location and identity of a foreign body, rigid bronchoscopy under general anesthesia is the gold-standard for diagnosis since the foreign body can be visualized and removed with this intervention. [2] Rigid bronchoscopy is indicated when two of the three following criteria are met: report of foreign body aspiration by the patient or a witness, abnormal lung exam findings, or abnormal chest x-ray findings. [2]

Management

See also: Choking § Treatment, Basic Life Support, Advanced Cardiovascular Life Support

Treatment of foreign body aspiration is determined by the age of the patient and the severity of obstruction of the airway involved. [2]

Basic management

An airway obstruction can be partial or complete. In partial obstruction, the patient can usually clear the foreign body with coughing. [2] In complete obstruction, acute intervention is required to remove the foreign body. [2]

If foreign body aspiration is suspected, finger sweeping in the mouth is not recommended due to the increased risk of displacing the foreign object further into the airway. [2]

For choking children less than 1 year of age, the child should be placed face down over the rescuer's arm. [2] Back blows should be delivered with the heel of the hand, then the patient should be turned face-up and chest thrusts should be administered. [2] The rescuer should alternate five back blows followed by five chest thrusts until the object is cleared. [2] The Heimlich maneuver should be used in choking patients older than 1 year of age to dislodge a foreign body. [2] If the patient becomes unresponsive during physical intervention, cardiopulmonary resuscitation (CPR) should be started. [2]

Advanced management

In the event that the basic measures do not remove the foreign body, and adequate ventilation cannot be restored, need for treatment by trained personnel becomes necessary. [2] Laryngoscopy should be performed in unresponsive patients if non-invasive airway clearance techniques are unsuccessful. [6] Laryngoscopy involves placing a device in the mouth to visualize the back of the airway. [6] If the foreign body can be seen, it can be removed with forceps. [6] An endotracheal tube should then be placed in order to prevent airway compromise from resulting inflammation after the procedure. [6] If the foreign body cannot be visualized, intubation, tracheotomy, or needle cricothyrotomy can be done to restore an airway for patients who have become unresponsive due to airway compromise. [2]

If non-invasive measures do not dislodge the foreign body, and the patient can maintain adequate ventilation, rigid bronchoscopy under general anesthesia should be performed. [2] Supplemental oxygen, cardiac monitoring, and a pulse oximeter should be applied to the patient. [6] Efforts should be made to keep the patient calm and avoid agitating the patient to prevent further airway compromise. [6] Flexible rather than rigid bronchoscopy might be used when the diagnosis or object location are unclear. When flexible bronchoscope is used, rigid bronchoscope is typically on standby and readily available as this is the preferred approach for removal. [14] Rigid bronchoscopy allows good airway control, ready bleeding management, better visualization, and ability to manipulate the aspirated object with a variety of forceps. [14] Flexible bronchoscopy may be used for extraction when distal access is needed and the operator is experienced in this technique. [14] Potential advantages include avoidance of general anesthesia as well as the ability to reach subsegmental bronchi which are smaller in diameter and further down the respiratory tract than the main bronchi. [14] The main disadvantage of using a flexible scope is the risk of further dislodging the object and causing airway compromise. [14] Bronchoscopy is successful in removing the foreign body in approximately 95% of cases with a complication rate of only 1%. [14]

After the foreign body is removed, patients should receive nebulized beta-adrenergic medication and chest physiotherapy to further protect the airway. [2] Steroidal anti-inflammatories and antibiotics are not routinely administered except in certain scenarios. [2] These include situations such as when the foreign body is difficult or impossible to extract, when there is a documented respiratory tract infection, and when swelling within the airway occurs after removal of the object. [14] Glucocorticoids may be administered when the foreign body is surrounded by inflamed tissue and extraction is difficult or impossible. [14] In such cases, extraction may be delayed for a short course of glucocorticoids so that the inflammation may be reduced before subsequent attempts. [14] These patients should remain under observation in the hospital until successful extraction as this practice can result in dislodgement of the foreign body. [14] Antibiotics are appropriate when an infection has developed but should not delay extraction. [14] In fact, removal of the object may improve infection control by removing the infectious source as well as using cultures taken during the bronchoscopy to guide antibiotic choice. [14] When airway edema or swelling occur, the patient may have stridor. In these cases, glucocorticoids, aerosolized epinephrine, or helium oxygen therapy may be considered as part of the management plan. [14]

Patients who are clinically stable with no need for supplemental oxygen after extraction may be discharged from the hospital the same day as the procedure. [4] Routine imaging such as a follow-up chest x-ray are not needed unless symptoms persist or worsen, or if the patient had imaging abnormalities previously to verify return to normal. [4] Most children are discharged within 24 hours of the procedure. [7]

Complications

Many complications can develop if a foreign body remains in the airway. There are also complications that may occur after removal of the object depending on the timeline of events. [2] Cardiac arrest and death are possible complications if a sudden complete obstruction occurs and immediate medical care is not performed. [7] The most common complication from a foreign body aspiration is a pulmonary infection, such as pneumonia or a lung abscess. [7] This can be more difficult to overcome in the elderly population and lead to even further complications. Patients may develop inflammation of the airway walls from a foreign body remaining in the airway. [2] Airway secretions can be retained behind the obstruction which creates an ideal environment for subsequent bacterial overgrowth. [7] Hyperinflation of the airway distal to the obstruction can also occur if the foreign body is not removed. [9] Episodes of recurrent pneumonia in the same lung field should prompt evaluation for a possible foreign body in the airway. [9]

Whether or not the foreign body is removed, complications such as chemical bronchitis, mucosal reactions, and the development of granulation tissue are possible. [11]

Complications can also arise from interventions used to remove a foreign body from the airway. [15] Rigid bronchoscopy is the gold standard for removal of a foreign body, however this intervention does have potential risks. [15] The most common complication from rigid bronchoscopy is damage to the patient's teeth. [15] Other less common complications include cuts to the mouth or esophagus, perforation of the bronchial tree, damage to the vocal cords, pneumothorax, atelectasis, stricture, and perforation. [7]

Prevention

There are many factors to consider when determining how to decrease the likelihood of aspiration, especially in the extremely young and elderly populations. [5]

The major considerations in children are their developmental level in terms of swallowing and protecting their airway via mechanisms such as coughing and the gag reflex. [5] Also, certain object characteristics such as size, shape, and material can increase their potential to cause choking among children. [5] When there are multiple children in a shared environment, toys and foods that are acceptable for older children often pose a choking risk to the younger children. [5] Education for parents and caretakers should continue to be prioritized when possible. This can be through positions such as pediatricians, dentists, and school teachers as well as media advertisements and printed materials. This education should include educating caretakers on how to recognize choking and perform first aid and cardiopulmonary resuscitation, check for warning labels and toy recalls, and avoid high risk objects and foods. [4]

Thanks to numerous public advancements, such as the Child Safety Protection Act and the Federal Hazardous Substance Act (FHSA), warning labels for choking hazards are required on packaging for small balls, marbles, balloons, and toys with small parts when these are intended for use by children in at-risk age groups. [5] Also, the Consumer Product Safety Improvement Act of 2008 amended the FHSA to also require advertisements on websites, catalogues, and other printed materials to include the choking hazard warnings. [5]

Related Research Articles

<span class="mw-page-title-main">Choking</span> Mechanical obstruction of the flow of air from the environment into the lungs

Choking, also known as foreign body airway obstruction (FBAO), is a phenomenon that occurs when breathing is impeded by a blockage inside of the respiratory tract. An obstruction that prevents oxygen from entering the lungs results in oxygen deprivation. Although oxygen stored in the blood and lungs can keep a person alive for several minutes after breathing stops, choking often leads to death.

<span class="mw-page-title-main">Cough</span> Sudden expulsion of air from the lungs as a reflex to clear irritants

A cough is a sudden expulsion of air through the large breathing passages which can help clear them of fluids, irritants, foreign particles and microbes. As a protective reflex, coughing can be repetitive with the cough reflex following three phases: an inhalation, a forced exhalation against a closed glottis, and a violent release of air from the lungs following opening of the glottis, usually accompanied by a distinctive sound.

<span class="mw-page-title-main">Hemoptysis</span> Medical symptom consisting of bloody mucus from coughing

Hemoptysis or haemoptysis is the discharge of blood or blood-stained mucus through the mouth coming from the bronchi, larynx, trachea, or lungs. It does not necessarily involve coughing. In other words, it is the airway bleeding. This can occur with lung cancer, infections such as tuberculosis, bronchitis, or pneumonia, and certain cardiovascular conditions. Hemoptysis is considered massive at 300 mL. In such cases, there are always severe injuries. The primary danger comes from choking, rather than blood loss.

<span class="mw-page-title-main">Bronchiectasis</span> Disease of the lungs

Bronchiectasis is a disease in which there is permanent enlargement of parts of the airways of the lung. Symptoms typically include a chronic cough with mucus production. Other symptoms include shortness of breath, coughing up blood, and chest pain. Wheezing and nail clubbing may also occur. Those with the disease often get lung infections.

<span class="mw-page-title-main">Pulmonary aspiration</span> Entry of materials into the larynx (voice box) and lower respiratory tract

Pulmonary aspiration is the entry of material such as pharyngeal secretions, food or drink, or stomach contents from the oropharynx or gastrointestinal tract, into the larynx and lower respiratory tract, the portions of the respiratory system from the trachea (windpipe) to the lungs. A person may inhale the material, or it may be delivered into the tracheobronchial tree during positive pressure ventilation. When pulmonary aspiration occurs during eating and drinking, the aspirated material is often colloquially referred to as "going down the wrong pipe".

<span class="mw-page-title-main">Airway management</span> Medical procedure ensuring an unobstructed airway

Airway management includes a set of maneuvers and medical procedures performed to prevent and relieve airway obstruction. This ensures an open pathway for gas exchange between a patient's lungs and the atmosphere. This is accomplished by either clearing a previously obstructed airway; or by preventing airway obstruction in cases such as anaphylaxis, the obtunded patient, or medical sedation. Airway obstruction can be caused by the tongue, foreign objects, the tissues of the airway itself, and bodily fluids such as blood and gastric contents (aspiration).

<span class="mw-page-title-main">Respiratory arrest</span> Medical condition

Respiratory arrest is a serious medical condition caused by apnea or respiratory dysfunction severe enough that it will not sustain the body. Prolonged apnea refers to a patient who has stopped breathing for a long period of time. If the heart muscle contraction is intact, the condition is known as respiratory arrest. An abrupt stop of pulmonary gas exchange lasting for more than five minutes may permanently damage vital organs, especially the brain. Lack of oxygen to the brain causes loss of consciousness. Brain injury is likely if respiratory arrest goes untreated for more than three minutes, and death is almost certain if more than five minutes.

<span class="mw-page-title-main">Atelectasis</span> Partial collapse of a lung causing reduced gas exchange

Atelectasis is the partial collapse or closure of a lung resulting in reduced or absent gas exchange. It is usually unilateral, affecting part or all of one lung. It is a condition where the alveoli are deflated down to little or no volume, as distinct from pulmonary consolidation, in which they are filled with liquid. It is often referred to informally as a collapsed lung, although more accurately it usually involves only a partial collapse, and that ambiguous term is also informally used for a fully collapsed lung caused by a pneumothorax.

<span class="mw-page-title-main">Aspiration pneumonia</span> Medical condition

Aspiration pneumonia is a type of lung infection that is due to a relatively large amount of material from the stomach or mouth entering the lungs. Signs and symptoms often include fever and cough of relatively rapid onset. Complications may include lung abscess, acute respiratory distress syndrome, empyema, and parapneumonic effusion. Some include chemical induced inflammation of the lungs as a subtype, which occurs from acidic but non-infectious stomach contents entering the lungs.

Stridor is a high-pitched extra-thoracic breath sound resulting from turbulent air flow in the larynx or lower in the bronchial tree. It is different from a stertor which is a noise originating in the pharynx.

A wheeze is a clinical symptom of a continuous, coarse, whistling sound produced in the respiratory airways during breathing. For wheezes to occur, part of the respiratory tree must be narrowed or obstructed, or airflow velocity within the respiratory tree must be heightened. Wheezing is commonly experienced by persons with a lung disease; the most common cause of recurrent wheezing is asthma, though it can also be a symptom of lung cancer, congestive heart failure, and certain types of heart diseases.

<span class="mw-page-title-main">Pneumonitis</span> General inflammation of lung tissue

Pneumonitis describes general inflammation of lung tissue. Possible causative agents include radiation therapy of the chest, exposure to medications used during chemo-therapy, the inhalation of debris, aspiration, herbicides or fluorocarbons and some systemic diseases. If unresolved, continued inflammation can result in irreparable damage such as pulmonary fibrosis.

<span class="mw-page-title-main">Respiratory disease</span> Disease of the respiratory system

Respiratory diseases, or lung diseases, are pathological conditions affecting the organs and tissues that make gas exchange difficult in air-breathing animals. They include conditions of the respiratory tract including the trachea, bronchi, bronchioles, alveoli, pleurae, pleural cavity, the nerves and muscles of respiration. Respiratory diseases range from mild and self-limiting, such as the common cold, influenza, and pharyngitis to life-threatening diseases such as bacterial pneumonia, pulmonary embolism, tuberculosis, acute asthma, lung cancer, and severe acute respiratory syndromes, such as COVID-19. Respiratory diseases can be classified in many different ways, including by the organ or tissue involved, by the type and pattern of associated signs and symptoms, or by the cause of the disease.

<span class="mw-page-title-main">Chest physiotherapy</span> Treatments to improve breathing by indirect removal of mucus from breathing passage

Chest physiotherapy (CPT) are treatments generally performed by physical therapists and respiratory therapists, whereby breathing is improved by the indirect removal of mucus from the breathing passages of a patient. Other terms include respiratory or cardio-thoracic physiotherapy.

<span class="mw-page-title-main">Bronchoscopy</span> Procedure allowing a physician to look at a patients airways

Bronchoscopy is an endoscopic technique of visualizing the inside of the airways for diagnostic and therapeutic purposes. An instrument (bronchoscope) is inserted into the airways, usually through the nose or mouth, or occasionally through a tracheostomy. This allows the practitioner to examine the patient's airways for abnormalities such as foreign bodies, bleeding, tumors, or inflammation. Specimens may be taken from inside the lungs. The construction of bronchoscopes ranges from rigid metal tubes with attached lighting devices to flexible optical fiber instruments with realtime video equipment.

<span class="mw-page-title-main">Tracheobronchial injury</span> Damage to the tracheobronchial tree

Tracheobronchial injury is damage to the tracheobronchial tree. It can result from blunt or penetrating trauma to the neck or chest, inhalation of harmful fumes or smoke, or aspiration of liquids or objects.

Double aortic arch is a relatively rare congenital cardiovascular malformation. DAA is an anomaly of the aortic arch in which two aortic arches form a complete vascular ring that can compress the trachea and/or esophagus. Most commonly there is a larger (dominant) right arch behind and a smaller (hypoplastic) left aortic arch in front of the trachea/esophagus. The two arches join to form the descending aorta which is usually on the left side. In some cases the end of the smaller left aortic arch closes and the vascular tissue becomes a fibrous cord. Although in these cases a complete ring of two patent aortic arches is not present, the term ‘vascular ring’ is the accepted generic term even in these anomalies.

<span class="mw-page-title-main">Basic airway management</span>

Basic airway management are a set of medical procedures performed in order to prevent airway obstruction and thus ensuring an open pathway between a patient's lungs and the outside world. This is accomplished by clearing or preventing obstructions of airways, often referred to as choking, cause by the tongue, the airways themselves, foreign bodies or materials from the body itself, such as blood or aspiration. Contrary to advanced airway management, minimal-invasive techniques does not rely on the use of medical equipment and can be performed without or with little training. Airway management is a primary consideration in cardiopulmonary resuscitation, anaesthesia, emergency medicine, intensive care medicine and first aid.

<span class="mw-page-title-main">Advanced airway management</span>

Advanced airway management is the subset of airway management that involves advanced training, skill, and invasiveness. It encompasses various techniques performed to create an open or patent airway – a clear path between a patient's lungs and the outside world.

Plastic bronchitis (PB) is a disorder in which branching casts of the airways are expectorated. PB is not a single disease with a defined mechanism that explains the cast formation in all conditions. Examples of diseases associated with expectoration of casts, and which sometimes are labeled PB include tuberculosis, atypical mycobacterial disease, allergic bronchopulmonary aspergillosis, and asthma.

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