In these cases, the obstruction is classified as a partial or complete obstruction. Signs of partial obstruction include choking with drooling, stridor, and the patient maintains the ability to speak. 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. A fever may be present. When this is the case, it is possible the object may be chemically irritating or contaminated.Foreign bodies above the larynx often present with stridor, while objects below the larynx present with wheezing. Foreign bodies above the vocal cords often present with difficulty and pain with swallowing and excessive drooling. Foreign bodies below the vocal cords often present with pain and difficulty with speaking and breathing. 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.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. 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.In adults, the right lower lobe of the lung is the most common site of recurrent pneumonia in foreign body aspiration.
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. This inadequate airway protection may also be attributed to poor dentition, seizure, general anesthesia, or sedative drug use. Diagnosis
The most important aspect of the assessment for a clinician is an accurate history provided by an event witness. 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. 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. Diagnostic Imaging
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. Lateral neck, chest, and bilateral decubitus end-expiratory chest x-rays should be obtained in patients suspected of having aspirated a foreign body. However, the presence of normal findings on chest radiography should not rule out foreign body aspiration as not all objects can be visualized. In fact, up to 50% of cases can have normal findings on radiography.