The diagnosis and treatment of foreign bodies in the airway are a challenge for otolaryngologists. Despite improvements in medical care and public awareness, approximately 3000 deaths occur each year from foreign body aspiration, with most deaths occurring before hospital evaluation and treatment. A high index of suspicion is needed for foreign body aspiration to allow for prompt treatment and avoidance of complications.[1, 2]
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Aspirated foreign body (backing to an earring) lodged in the right main stem bronchus.
Until the late 1800s, airway foreign body removal was performed by bronchotomy. The first endoscopic removal of a foreign body occurred in 1897. Chevalier Jackson revolutionized endoscopic foreign body removal in the early 1900s with principles and techniques still followed today. The development of the rod-lens telescope in the 1970s and improvements in anesthetic techniques have made foreign body removal a much safer procedure.
Most airway foreign body aspirations occur in children younger than 15 years; children aged 1-3 years are the most susceptible. Vegetable matter tends to be the most common airway foreign body; peanuts are the most common food item aspirated. The incidence of metallic foreign body aspirations, particularly of safety pins, has decreased in frequency secondary to the advent of disposable diapers.
A study by Cheng et al, using the Kids’ Inpatient Database (KID), found that between 2000 and 2009, the mean annual hospital admission rate in the United States for children diagnosed with an airway foreign body was 6.6 per 10,000 pediatric patients.[3]
Mortality
Another report by Cheng and colleagues determined that between 2000 and 2009, US pediatric inpatients with airway foreign bodies had a weighted mortality rate of approximately 2.75%, with the rate staying relatively unchanged over that period.[4]
After foreign body aspiration occurs, the foreign body can settle into 3 anatomic sites, the larynx, trachea, or bronchus.
Of aspirated foreign bodies, 80-90% become lodged in the bronchi.
In adults, bronchial foreign bodies tend to be lodged in the right main bronchus because of its lesser angle of convergence compared with the left bronchus and because of the location of the carina left of the midline.
Several papers have demonstrated equal frequency of right and left bronchial foreign bodies in children.
Larger objects tend to become lodged in the larynx or trachea.
In general, aspiration of foreign bodies produces the following 3 phases:
Initial phase - Choking and gasping, coughing, or airway obstruction at the time of aspiration
Asymptomatic phase - Subsequent lodging of the object with relaxation of reflexes that often results in a reduction or cessation of symptoms, lasting hours to weeks
Complications phase - Foreign body producing erosion or obstruction leading to pneumonia, atelectasis, or abscess
Clinical presentation depends on the location of the foreign body. A large foreign body lodged in the larynx or trachea can produce complete airway obstruction from either the dimensions of the object or the resulting edema.
Laryngeal foreign bodies present with airway obstruction and hoarseness or aphonia.
Tracheal foreign bodies present similarly to laryngeal foreign bodies but without hoarseness or aphonia. Tracheal foreign bodies can demonstrate wheezing similar to asthma.
Bronchial foreign bodies typically present with cough, unilateral wheezing, and decreased breath sounds, but only 65% of patients present with this classic triad.
Foreign body aspiration can mimic other respiratory problems, such as asthma. Foreign body aspiration differs in the presence of unilateral wheezing and decreased breath sounds.
Perform surgical intervention with rigid bronchoscopy on patients who have a witnessed foreign body aspiration, those with radiographic evidence of an airway foreign body, and those with the previously described classic signs and symptoms of foreign body aspiration. The history and physical examination are the most important aspects in the decision for surgical intervention. A strong history of suspected foreign body aspiration prompts an endoscopic evaluation, even if the clinical findings are not as conclusive or are not present.
Airway foreign bodies can become lodged in the larynx, trachea, and bronchus. The size and shape of the object determine the site of obstruction; large, round, or expandable objects produce complete obstruction, and irregularly shaped objects allow air passage around the object, resulting in partial obstruction.
No contraindications exist to the removal of an airway foreign body from a child. If necessary, health problems can be optimized before surgical intervention. However, even children who are at high risk due to health reasons still need surgical intervention to remove the foreign body.
High-kilovolt anteroposterior and lateral radiographs of the airway are the tests of choice in patients in whom laryngeal foreign bodies are suspected. The high kilovoltage used produces greater definition of the airway while reducing the effect of the surrounding bony structures.
Posteroanterior and lateral chest radiographs are an adjunct to the history and physical examination in patients in whom foreign body aspirations are suspected. To at least have a baseline study for future comparison, perform chest radiographs on all such patients. Radiopaque objects are visible, but radiolucent objects (eg, plastic) are not.[5] Chest radiographs may reveal obstructive emphysema or hyperinflation, atelectasis, and consolidation.
Lateral decubitus chest films may be helpful in children in whom the dependent lung remains inflated with bronchial obstruction. Typically, the dependent lung collapses.
Chest radiographs (inspiratory and expiratory films) demonstrate atelectasis on inspiration and hyperinflation on expiration with a foreign body obstructing the bronchus.
A recent study demonstrated an increase in false positives with lateral decubitus films and a questionable benefit with expiratory films when used in conjunction with plain chest radiography.[6]
Biplane fluoroscopy uses intraoperative fluoroscopic evaluation while identifying and locating a foreign body within the lung periphery.
A study by Behera et al indicated that virtual bronchoscopy using multidetector computed tomography (MDCT) scanning is effective in diagnosing the presence of radiolucent vegetable foreign bodies in the tracheobronchial airway. The study found that in 59 out of 60 pediatric cases, rigid bronchoscopy confirmed MDCT-scan findings with regard to the presence of a vegetable foreign body, as well as the foreign body’s size, shape, and location, giving virtual bronchoscopy a positive predictive value of 98.3%.[7]
Chest auscultation is critical in the evaluation of a patient in whom a foreign body aspiration is suspected. Typically, these patients have wheezing, decreased breath sounds, or both on the side of the foreign body. Patients may have normal examination findings despite having a foreign body within the airway because it may partially obstruct the airway.
Patients with complete airway obstruction require immediate medical attention and typically are aphonic and unable to breathe. Patients who are coughing, gagging, and vocalizing have partial obstruction.
Use of the Heimlich maneuver has improved the mortality rate of patients with complete airway obstruction, but use of it in patients with partial obstruction may produce complete obstruction.
Most patients who arrive at the hospital are beyond the acute stage and are not in respiratory distress.
After a complete history and physical examination are completed and radiographic studies are performed, a decision is made in regard to the need for surgical intervention.
In most cases, antibiotics and steroids are not administered initially.
An operating room well equipped with proper endoscopic equipment of various sizes, personnel familiar with the use of the instrumentation, and anesthesiologists experienced in foreign body removal are critical for safe removal of airway foreign bodies.
Select and organize age-appropriate endoscopic equipment before the patient enters the operating room. Various foreign body forceps should be available for use, and a similar object should be available for comparison. Communication between the endoscopist and anesthesiologist before the procedure to outline a plan of action is critical. Prior to surgical intervention in patients who are not in respiratory distress, the patient should remain on nothing by mouth (NPO) status for an adequate period to prevent aspiration.
Use inhalational anesthetics to anesthetize patients. Apply 1-2% lidocaine to the larynx to reduce reflexes and prevent laryngospasm. Keep patients spontaneously breathing throughout the procedure for control of the airway.
With laryngeal foreign bodies, use an insufflation catheter through the nose with the tip in the hypopharynx to maintain anesthesia and oxygenation. The laryngoscope tip is placed in the vallecula for exposure, and the foreign body is visualized in the larynx and removed with appropriate foreign body forceps. After removal, reassess the larynx for other foreign bodies. Perform rigid bronchoscopy afterward to assess for other foreign bodies in the lower airway.
In tracheobronchial foreign body removal, the bronchoscope is inserted into the airway after exposure to the larynx, and continuous ventilation of the patient is provided through the bronchoscope. In a patient with a bronchial foreign body, the unaffected side is examined first. The bronchoscope then is placed immediately above the foreign body. Secretions are gently suctioned around the object. The patient is oxygenated with 100% oxygen before any attempt at removal. The forceps are placed through the bronchoscope, and the object is grasped after complete visualization of the foreign body. The bronchoscope is advanced to the foreign body while the surgeon continues to grasp the object. The foreign body, foreign body forceps, and bronchoscope are removed as a unit, and the bronchoscope immediately is returned to the airway for ventilation and reassessment for other foreign bodies.
Occasionally, easy retrieval of the foreign body is not possible. Larger objects unable to pass through the larynx can be broken into pieces and removed. If the object cannot pass through the larynx, a tracheotomy can be performed to remove the object through the tracheostoma. At times, the object becomes embedded into the surrounding mucosa because of edema caused by the object or because of multiple failed attempts at removal. In this situation, stop and to wait 48-72 hours to allow the edema to subside for a repeat attempt at removal. Thoracotomy may be necessary when the object stays embedded after failed endoscopic attempts.
Foreign bodies in the distal bronchial segments may be removed with the use of a Fogarty endovascular catheter through the suction port of a rigid bronchoscope. Flexible bronchoscopy as an adjunct may be beneficial in the removal of distal objects.
Sharp objects are extremely challenging for endoscopic removal. The pointed end tends to engage in the mucosa, causing the object to tumble with the point trailing. Pointed objects tend to be bendable or breakable. The bronchoscope is placed into the airway, and, using foreign body forceps, the pointed end of the object is disengaged from the mucosa, moved distally, and then removed. Pin-bending forceps may be used in certain situations. Safety pin removal is uniquely challenging; removal is performed endoscopically by sheathing the pointed end into the endoscope and locking the keeper outside the endoscope. Open removal by thoracotomy may be necessary when the sharp object is severely embedded into the mucosa.[8]
The use of steroids or racemic epinephrine is not necessary when age-appropriate endoscopes are used. Antibiotics typically are not prescribed because the source of infection has been removed. Chest physiotherapy is performed after foreign body removal to help remove secretions. Patients are discharged when fully awake and breathing comfortably without the need for supplemental oxygen. Chest radiographs are performed postoperatively if the patient's signs and symptoms persist or worsen.
Follow-up care is necessary if the patient's signs and symptoms return after discharge. For excellent patient education resources, see eMedicineHealth's patient education article Bronchoscopy.
Most complications are the result of a delay in diagnosis.
Of patients with laryngotracheal foreign bodies, 67% experience associated complications when the removal delay is more than 24 hours.
Pneumonia and atelectasis are the most common complications secondary to and after removal of bronchial foreign bodies.
Bleeding can occur from granulation tissue surrounding the foreign body or erosion into a major vessel.
Pneumothorax and pneumomediastinum can result from an airway tear.
A study by Kinoshita et al found that patients who, in the presence of a bystander, choked on a foreign body during a meal and became unresponsive or unconscious had a better neurologic outcome if the bystander performed chest compressions. The study, which included 138 patients who became unresponsive or unconscious due to foreign body airway obstruction, also found better outcomes among patients who did not suffer cardiopulmonary arrest during this episode. However, attempts to remove the foreign object from the patient before emergency medical technicians arrived were reported not to improve outcome.[9]
Literature describes other means of foreign body removal. Chest physiotherapy and bronchodilators have been suggested in the past but are not currently recommended as treatment. Some have advocated flexible bronchoscopic removal of all foreign bodies in children, but poor airway control and the need for the immediate availability of rigid endoscopic equipment limit its use as an exclusive intervention.
Predictive models using computerized scoring systems may help in more specifically identifying those children with and without foreign body aspiration.[10] Simulation training may aid in preparation of future otolaryngologists involved with foreign body removal in children.
A retrospective study by Ng et al indicated that in adults, retrieval of an aspirated foreign body through flexible bronchoscopy is more likely to fail in patients who have undergone failed previous attempts at removal, in whom diagnosis has been delayed, or in whom the object is peripherally located. On the other hand, the investigators found that rigid bronchoscopy could successfully remove airway foreign bodies in the context of previous failures, and delayed diagnosis, and could retrieve hard solid objects.[11]
Alan D Murray, MD, Pediatric Otolaryngologist, ENT for Children; Full-Time Staff, Medical City Dallas Children's Hospital; Consulting Staff, Department of Otolaryngology, Children's Medical Center at Dallas, Cook Children's Medical Center; Full-Time Staff, Texas Pediatric Surgery Center, Cook Children's Pediatric Surgery Center Plano
Disclosure: Nothing to disclose.
Specialty Editors
Francisco Talavera, PharmD, PhD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference
Disclosure: Received salary from Medscape for employment. for: Medscape.
Chief Editor
Arlen D Meyers, MD, MBA, Professor of Otolaryngology, Dentistry, and Engineering, University of Colorado School of Medicine
Disclosure: Serve(d) as a director, officer, partner, employee, advisor, consultant or trustee for: Cerescan;RxRevu;Cliexa;The Physicians Edge;Sync-n-Scale;mCharts<br/>Received income in an amount equal to or greater than $250 from: The Physicians Edge, Cliexa<br/> Received stock from RxRevu; Received ownership interest from Cerescan for consulting; .
Additional Contributors
Daniel J Kelley, MD, Consulting Staff, Eastern Shore ENT and Allergy Associates and Peninsula Regional Medical Center
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