Chapter 44. Management of a 12-Year-Old Child with a Foreign Body in the Bronchus

An 88-lb (40 kg), 12-year-old-boy with a history of cervical spine fusion due to syringomyelia presents to the hospital following the accidental inhalation of a pushpin during sneezing. There is no associated thoracic scoliosis or any neuromuscular deficit. He is otherwise healthy, takes no medications, and has no known drug allergies.

44.2.1 What Are the Initial Clinical Steps in Patient Management?

Initial management when presented with a definitive history of aspiration of a foreign body begins with the ABCs. An awake, alert patient without overt airway distress will permit a more complete workup, while a severely distressed patient with stridor and desaturation will mandate acute stabilization prior to transfer to the operating room for surgical removal. All patients should have pulse oximetry. Supplemental oxygen may be provided to maximize oxygenation. To optimize patient care and potentially minimize the need for emergency intervention, a member of the anesthesia or surgical team should accompany the patient during airway stabilization and transportation to the operating room.

Respiratory distress or the presence of stridor implies compromise of the airway and reduced airflow. Heliox 70/30 (70% helium and 30% oxygen) will improve oxygenation by maximizing laminar airflow and reducing airflow resistance. The use of Heliox serves as a temporizing measure in the setting of foreign body aspiration in young children as it decreases the work of breathing and the associated anxiety.1 Intravenous dexamethasone at a dose of 0.5 mg·kg−1 may be beneficial in reducing the mucosal edema which partly contributes to the airway obstruction.2 Aerosolized epinephrine may be an additional means of reducing airway edema. The use of bronchodilators is considered to be relatively contraindicated until the foreign body is removed from the airway, as its use may predispose to dislodgement and distal migration of the foreign body due to an increase in airway caliber. Bronchodilators, however, are important adjuncts to pulmonary toilet following foreign body removal.3

44.2.2 What Are the Appropriate Investigations for a Foreign Body in the Trachea?

Radiologic studies are used as an adjunct to the physical examination in diagnosing suspected aerodigestive foreign bodies. Anteroposterior and lateral chest radiographs with inspiratory and expiratory views are helpful tools if the foreign body is opaque, or if there is evidence of bronchial obstruction. Typical findings will reveal a foreign body shadow, air trapping, segmental or lobar collapse, or consolidation. Unfortunately, the false-negative rate (ie, normal chest x-ray) ranges between 24% and 33% when compared to bronchoscopic findings.4

Spiral CT has shown some benefit when faced with persistent symptoms in a pediatric patient in the setting of an atypical history and normal chest x-ray. Fluoroscopy and cine CT are of little added benefit when a timely workup is of essence, especially if a plain radiograph or spiral CT has already confirmed the presence of a foreign body.4 Ultimately, the gold standard for diagnosing an aspirated foreign body is rigid bronchoscopy under general anesthesia.3,5

44.2.3 Do Different Types of Foreign Bodies (Organics, Metals, Plastics) Influence Patient Management and Outcomes?

Organic matter (nuts, corn, seeds, etc) and plastics are radiolucent items that are not commonly visualized on x-ray. Organics must be removed as soon as possible as the diameter of the object will increase over time due to the absorption of secretions and moisture. This may convert a stable, partial obstruction to an acute, complete obstruction, or obliterate the available space around the foreign body complicating removal with forceps. Furthermore, over time the organic matter will become more friable, potentially breaking into multiple pieces, making complete removal very difficult. This enhances the risk of obstruction and infection in the distal, smaller generation bronchi.

44.2.4 What Are the Pathophysiologic Changes in the Presence of an Aspirated Foreign Body?

Determining the site of airway obstruction, the size and shape of the aspirated object, and the timeline since obstruction are crucial to patient outcomes and guide the plan for removal. Airway obstruction following foreign body aspiration may be total or partial, depending on all of the above factors. The incidence of foreign body aspiration is not dependent on socioeconomic status or geographic location. However, there is a relationship in the type of aspirated object, particularly if it is a food substance that is dependent on the age of the patient and the country in which the patient resides.

Toddlers, under 3 years, are at highest risk of foreign body aspiration as they explore their environment by placing encountered objects in their mouths, are more likely to talk, laugh, and run while eating, have relatively immature laryngeal protective reflexes,5 and incomplete dentition. The most commonly aspirated organics are nuts (peanut, sunflower seed), meat (chicken, hot dog), popcorn, and carrots. Fatalities are most frequent with hot dogs and other meats, candies, grapes, and peanuts.6

A foreign body lodged in the lower airway may manifest with different pulmonary findings depending on the type of impaction. Four lower airway obstructive mechanisms have been described: check valve, ball valve, bypass valve, and stop valve.7 Check valve implies air can be inhaled but not exhaled, creating alveolar air trapping and flattening of the ipsilateral diaphragm. This is in contrast to a ball valve which allows expiration but not inspiration of air, creating segmental bronchopulmonary collapse. A bypass valve obstruction allows partial airflow on both inspiration and expiration around the foreign body and may not exhibit specific clinical findings. A stop valve creates complete obstruction to airflow, causing airway collapse and consolidation distal to the obstruction.7

The ability to correctly ascertain the type of obstruction and object aspirated may help determine the stability of the patient's airway and the requisite acuity of intervention. This key point is of utmost importance when the patient is not distressed, possibly lulling the practitioner into a false sense of (airway) security.

44.3.1 What Are the Usual Clinical Presentations of a Foreign Body in the Airway with or without Airway Obstruction and Air Trapping? What Are the Specific Airway Concerns in This Patient?

Presenting symptoms following foreign body aspiration are related to the type of object aspirated, location of the object within the airway, and the overall duration of the obstructive event. Airway obstruction may be complete or partial. Complete obstruction of the trachea or large airway is an emergency situation usually associated with hypoxemia, cardiovascular compromise, and subsequent collapse. In contrast, partial obstruction can often present with more subtle symptoms such as coughing, focal or diffuse wheezing, and decreased air entry on the affected side.3,8 These may progress over time to drooling, dyspnea, stridor, and respiratory distress.

It is critical to appreciate that to produce symptoms a foreign body must encroach on 75% of the airway lumen to create turbulent airflow. This degree of obstruction may occur acutely, due primarily to the foreign body itself or secondarily, due to the local tissue reaction. Aspiration of organic matter will promote, over time, local airway swelling and the production of granulation tissue. Thus even a small foreign body can produce significant obstructive symptoms when left in the airway for as little as 5 to 7 days. This generally necessitates immediate intervention to avoid a disastrous outcome.8

In this patient, the aspirated foreign body may be found anywhere in the upper airway, down to the level of the carina, and occasionally in the mainstem bronchi. Sharp objects, like pins, will generally be found with the sharp end embedded in the mucosa proximally, while the larger, blunt end is distal. It is unlikely that a pushpin, in and of itself, would cause obstruction of the larger airways. However, the associated mucosal edema, and/or displacement into the smaller generation bronchi, may create airway obstruction.

Our patient is able to provide an accurate history of aspiration and subsequent, persistent cough. His airway is currently stable. However, his previous cervical fusion may provide a challenge for both the anesthesia practitioner and endoscopist. The following sections will further delve into anesthetic management and the surgical options presented by this challenging scenario. A key principle in managing the airways of children is to ensure communication between the anesthesia practitioner and the surgeon prior to the patient's arrival in the operating room. It is essential that the surgical setup be ready prior to the induction of anesthesia, that a backup plan has been discussed and agreed upon, and that the equipment for performing a surgical airway is available.

44.4.1 What Are the Anesthetic Options If the Patient Is Uncooperative? How Would You Approach the Induction of This Patient?

Children with airway obstruction pose a challenge to the anesthesia practitioner. Physiologically, children have a limited functional residual capacity (FRC), reduced respiratory reserve, increased shunting, and a propensity for airway closure (laryngospasm and bronchospasm). In the setting of a relative increase in oxygen consumption and suboptimal ventilation, the anesthesia practitioner is faced with a patient who will likely develop hypoxemia rapidly. An inhalation induction may be prolonged if there is reduced alveolar ventilation due to airway obstruction.

Anesthetic management in the setting of foreign body aspiration is predicated on providing a safe anesthetic for the patient, while maintaining control of the airway and preventing the undesirable physiologic responses associated with airway manipulation. Inhalational agents may provide an optimal technique to maintain control of the airway.8 Halothane and sevoflurane provide the most rapid and uneventful induction in this scenario. Sevoflurane may be the preferred inhalational agent because it allows for a smooth and rapid induction of general anesthesia. In addition, sevoflurane has antitussive properties and far greater cardiorespiratory stability than halothane.9 The other fluorinated inhalational agents, such as isoflurane, enflurane, and desflurane, are more likely to produce airway irritation on induction and are commonly avoided. However, they may be used following induction to maintain a deep plane of anesthesia.8

Anticholinergics (atropine and glycopyrrolate) block vagally mediated airway responses, such as excessive production of airway secretions, bradycardia, and bronchoconstriction.8 Topical lidocaine works synergistically with the inhalational agent decreasing the physiologic response to laryngoscopy and bronchoscopy. Intravenous opioids, such as remifentanil and fentanyl, are also helpful in suppressing airway reflexes and may be used as an adjunct to the anesthetic, ensuring that the airway is already secured, as there may be associated respiratory depression.8,10 Total intravenous anesthesia with propofol infusion is also a feasible option, as long as spontaneous respiration is maintained. Similarly, small doses of short-acting muscle relaxants provide short-term neuromuscular blockade, inhibit coughing, facilitate oxygenation, and minimize atelectasis.10 The use of muscle relaxants, once again, mandates prior stabilization and control of the airway.10,11

It is generally felt that positive pressure ventilation (PPV) is to be avoided as this may lead to dislodgement and distal displacement of the foreign body.8,10 However, in a retrospective review of 94 children with tracheal and bronchial foreign body, Litman et al found that neither spontaneous nor controlled ventilation was associated with an increased incidence of adverse events.10 Nitrous oxide should also be avoided because it decreases the percentage of delivered oxygen, encourages atelectasis, and expands cavities containing trapped air. Indeed, augmentation of air that is trapped may be of sufficient magnitude to severely compromise pulmonary compliance and generate a pneumothorax.8 Although some might consider awake-intubation to be an option, in this patient, it is likely to be stormy with the potential to dislodge the pushpin and create a more hazardous situation.

When faced with an uncooperative patient or a precarious airway, an intramuscular agent, such as ketamine, may provide a window of opportunity for an inhalation induction, without significant depression of the respiratory drive.12

Although the patient with a foreign body in the airway is considered at high risk for aspiration, the urgency of the airway status takes precedence. If immediate intervention is not indicated, some advocate a waiting period for the patient with a full stomach, while others believe that the stress associated with foreign body aspiration is likely to inhibit gastric emptying and advise against waiting. Likewise, some advocate a rapid-sequence induction to protect the airway, although most believe that a slow inhalation induction with spontaneous ventilation is associated with minimal risk of aspiration and maximizes control. If, however, bag-mask-ventilation is required to maintain or regain control of the airway, then the risk of aspiration increases, mandating early control of the airway.8-11

In this case, our patient provides an interesting twist, as the complexity of the challenge is enhanced by limited neck extension. This case also reflects the importance of communication among the team of caregivers and highlights the need for an alternate plan should the initial approach fail. The inability to predict whether the airway will be easily accessed provides a strong argument for a slow, spontaneous ventilation induction, with topicalization of the airway using lidocaine. Should the airway not be visualized on laryngoscopy, or with a rigid bronchoscope, other modalities may be attempted (McGrath video laryngoscope, lightwand, laryngeal mask airway, etc) provided one has ascertained that blind techniques will not lead to dislodgement or impaction of the foreign body. The specifics of airway management for our patient scenario will be discussed in depth in the next section.

44.5.1 How Do You Perform Rigid Bronchoscopy for Foreign Body Removal?

A complete airway assessment is fundamental to planning the approach to remove the foreign body and preparing for difficulties that might be encountered. Our patient has had a cervical fusion potentially limiting neck extension, making laryngoscopy and rigid bronchoscopy challenging, if not impossible. The safest means of removing a sharp foreign body requires that under direct vision it be grasped, released from its hold on the mucosa by advancing it more distally, and then sheathing it within the rigid bronchoscope for removal when the bronchoscope is withdrawn. Large tracheal foreign bodies that cannot be ensheathed within the bronchoscope are likely to become impacted at the level of the glottis during removal, potentially leading to complete airway obstruction. In situations where obstruction is, or becomes, complete, the object may need to be rapidly pushed distally, usually into the right mainstem bronchus.

It is important to note that the entire airway, trachea, and first- and second-generation bronchi must be visualized following removal of the foreign body to ensure the absence of trauma or a second airway foreign body, which may be present in up to 5% of foreign body aspirations.13

44.5.2 How Do You Provide Oxygenation during Rigid Bronchoscopy?

Provided that an appropriately sized bronchoscope is used, rigid bronchoscopy allows for oxygenation through side ports. Newer endoscopic technology allows visualization of the airway on a monitor. The advent of endoscopic foreign body forceps allows spontaneous ventilation through the bronchoscope, with minimal loss of anesthetic gases into the operating room and better maintenance of the depth of anesthesia. Depending on the type and shape of the object to be retrieved, a selection of endoscopic foreign body forceps should be available.

44.5.3 What Are the Potential Complications and Limitations of Rigid Bronchoscopy?

Complications of rigid bronchoscopy include: dental injury, cervical spine injury (due to aggressive patient positioning or underlying patient disorder), glottic or arytenoid injury, and posterior tracheal wall tear which may occasionally lead to the formation of a tracheoesophageal fistula. Hemodynamic instability, hypercapnia, or hypoxemia may also occur in association with hypoventilation, dislodgement of the foreign body, or the use of an inappropriately large bronchoscope limiting insufflation and efflux of gases. Rigid bronchoscopes in the tracheobronchial tree have limited maneuverability and cannot access secondary bronchi and smaller airways.

44.5.4 What Is the Role of Flexible Bronchoscopy in the Management of Foreign Bodies in the Airway?

The use of flexible bronchoscopy (FB) as a primary tool for foreign body removal is not widely practiced. Some advocate its use to evaluate the airway prior to foreign body removal by rigid bronchoscopy to allow for localization and planning.14 It may also be used following retrieval to ensure that the foreign body has been removed in its entirety and no other foreign bodies exist. A group in Mexico is currently using FB in approximately 40% of their pediatric airway foreign body cases, with a 93% success rate.15

The risks of using FB for foreign body removal are multifaceted. It is customary to secure the airway with an endotracheal tube prior to endoscopy, as there are no ventilation ports. There is a limited selection of grasping forceps that may be passed through the channel of the FB. The foreign body cannot be ensheathed within the FB to protect the airway during its removal, potentially increasing the risk of injury to the airway if the object is sharp. It also increases the risk of complete airway obstruction, if the object is dropped as it is retracted proximally.

44.5.5 What Is the Incidence of an Open Surgical Procedure to Remove Foreign Bodies from the Airway?

Open surgical procedures are seldom required to remove foreign bodies from the airway. Such an approach is generally required in a setting where rigid bronchoscopy has failed or in the following situations: (1) if the foreign body is found in a small, inaccessible peripheral bronchus; (2) if the foreign body is sharp, pointed, and embedded in the tracheal or bronchial wall; (3) if it has been present for a prolonged period of time, often for several years; and (4) if there is significant difficulty in maintaining control of the airway following rigid bronchoscope insertion and manipulation. Interestingly, aspirated plastic pen caps more often require open surgical procedures due to a high rate of bronchoscopic extraction failure secondary to their size, shape, and position in the airway.16,17

44.5.6 How Do You Remove the Foreign Body from This Patient?

Because of the limitation of cervical spine movement and the anticipated difficulty in performing a rigid bronchoscopy in this patient, once the airway was controlled, a temporary tracheotomy was performed through which a rigid bronchoscope was passed to retrieve the pushpin.

In cases such as this, the tracheotomy may be closed primarily provided that there is minimal airway edema compromising the lumen, and recognizing that there is a small risk of air leak into the neck with primary closure. If the patient is expected to cough or strain, or require ventilatory assistance, then primary closure may not be the best option.

If an object still cannot be removed, an open thoracotomy is required. In such cases, a bronchotomy or partial lung parenchymal resection may be necessary to remove the object. The latter is more commonly seen when the diagnosis of foreign body aspiration is delayed and secondary complications, such as bronchiectasis, empyema, segmental collapse, or recurrent pneumonia have occurred.3

44.6.1 Is There a Role for Steroids, Aerosolized Epinephrine, Bronchodilators, and Antibiotics in the Postoperative Care of This Patient?

The use of steroids in the postoperative period may be beneficial if mucosal edema and granulation tissue were present in the vicinity of the airway foreign body. Aerosolized epinephrine is unlikely to be needed unless faced with postoperative stridor following traumatic foreign body removal. Bronchodilators are used infrequently, but may be helpful in the presence of persistent segmental atelectasis, more commonly seen if the foreign body has been present for a prolonged period of time. Similarly, antibiotics are not used routinely, unless there is evidence of perforation, granulation tissue or suppuration around the foreign body, or in the distal airways.3

44.6.2 What Investigative Modalities Are Warranted Postoperatively? What Is the Appropriate Management of This Patient If the Immediate Postoperative Chest Radiograph Shows the Presence of Pneumomediastinum?

Postoperatively, the patient should be observed upon emergence from anesthesia to ensure that there are no sequelae, such as airway compromise or respiratory distress, following foreign body retrieval. If the object was small and completely removed, with minimal underlying airway edema, the patient may be discharged following a brief period of observation. Difficult retrievals or instability in the operating or recovery rooms definitely mandate overnight-monitored observation.

If the patient exhibits pneumomediastinum on postoperative chest x-ray, clinical symptomatology must be correlated to determine whether further investigation or invasive therapies are warranted. Most commonly, there are few signs or symptoms associated with pneumomediastinum, precordial crepitus and voice change being the most common. Ideally, PPV should be avoided if possible as this may exacerbate the situation. Generally, such patients are monitored in an intensive care setting and are subject to serial chest radiographs to monitor regression or progression. Usually there is slow resolution over a few days, without significant sequelae.

Airway foreign bodies in children can pose multiple challenges. The task of removing the object requires a team approach for the best possible patient outcome. Gathering as much information as possible prior to entering the operating room will enable better planning for foreign body retrieval, while keeping the patient's safety at the forefront. The size and nature of the aspirated object, its location in the airway, the time elapsed since aspiration, and patient factors such as age, and other associated comorbidities, all weigh into the planning of retrieval. Communication, preparation, and practice are the means by which successful outcomes are achieved.