Upper Respiratory Distress Could Be Caused by a Laryngeal Foreign Body

When most mothers hear their child with a crowing or barking noise, a hoarse voice, or cough, they usually assume that croup is the culprit. However, their maternal instincts may be wrong for these symptoms are also typical of a laryngeal foreign body (LFB), and the diagnosis may be missed unless it is specifically considered in all young children presenting with stridor (a high-pitched, noisy respiration, like the blowing of the wind; a sign of respiratory obstruction, especially in the trachea or larynx) of acute onset.

A laryngeal foreign body is a very uncommon cause of a common symptom complex in pediatrics. Croup, which is the commonest cause of acute stridor in children, has a peak incidence of 60 cases per 1000 children per year between the ages of one and two years. In contrast, LFB accounts for only two percent to nine percent of all inhaled airway foreign bodies in children. LFB has also been observed to occur at an earlier age compared with tracheobronchial foreign bodies, because the subglottis is the narrowest part of the airway in young children.

Many parents are well aware of the dangers posed by food, such as a piece of hot dog, which are large, sit perfectly in a larynx, and occlude the airway completely. This study addresses small bits of plastic or metal, which in the first instance would not completely occlude the airway, but if unrecognized and not removed, lead to increased laryngeal swelling and obstruction. This swelling and partial obstruction can lead to symptoms that mirror croup. As a means of highlighting the potential significance of this condition, a team of Australian medical researchers undertook a retrospective review of their experience with LFB in nine children over the past 13 years.

The authors of "Laryngeal Foreign Bodies in Children Revisited" are Robert G Berkowitz MD FRACS, from the Department of Otolaryngology Royal Children's Hospital and Department of Paediatrics, University of Melbourne, Melbourne, Australia and Wye-Keat Lim MBBS, from the University of Melbourne. Their findings are being presented at a poster session of the Combined Otolaryngological Societies Meeting being May 1-6, 2003, at the Gaylord Opryland Hotel, Nashville, TN.

Methodology: A retrospective chart review was carried out of patients admitted to the Royal Children's Hospital, Melbourne, Australia, with a diagnosis of LFB between March 1989 and March 2002. Only patients who had endoscopically proven foreign bodies removed under general anesthetic from the supraglottis, glottis, or subglottis were included. Two patients were dead on arrival at the institution as a result of acute upper airway obstruction due to a foreign body, but as the site of impaction was not confirmed endoscopically, they were not included in this study.

Results: Nine patients (5 male 4 female) were identified with LFB confirmed at laryngoscopy under general anesthetic. Their ages ranged from five months to 13 years, nine months (mean 34 months, median 12 months), with only one child older than 32 months. All children were otherwise healthy with no significant other medical disorders or illnesses.

Four patients were referred to the medical institution following a witnessed choking episode due to foreign body inhalation, and underwent laryngoscopy and foreign body removal within 24 hours of the event (early group). Diagnosis and treatment was delayed in five children, and ranged from four days to two months after onset of symptoms, including two children in whom there had been a witnessed choking episode.

All four patients in the early group had a preoperative diagnosis of LFB, with the diagnosis being confirmed by radiology in two and awake flexible laryngoscopy in one. In the late group, one had a diagnosis of LFB made by awake flexible laryngoscopy three weeks after presenting to our institution with a history suggestive of foreign body inhalation (he was initially found to have right lower lobe changes on chest Xray and had been treated with oral antibiotics). The other four patients in the late group were initially managed outside the research institution, with the diagnosis of croup (2), bronchiolitis (1), and asthma (1), but were referred for airway endoscopy because of persistence of symptoms.

Foreign body removal was uneventful in all nine cases, and eight patients were discharged within 48 hours of surgery and were free of symptoms. One patient in the late group developed laryngeal edema within an hour of foreign body removal and required endotracheal intubation. Because of absence of an air leak, he remained intubated for seven days but was uneventfully extubated, and discharged after a further two days.

Conclusions: All but one patient in the series was under three years of age. This made the diagnosis of LFB difficult to differentiate from croup in the absence of a witnessed choking episode, due to the similar age presentation as croup, and the inability of a young child to volunteer a history of foreign body inhalation.

Based on the researchers' experience and published data, LFB can be classified into three groups: impaction of a bulky object, usually a food item, which causes immediate severe upper airway obstruction or death; witnessed choking episode associated with a degree of stridor, leading to expeditious removal; presentation with croup-like symptoms in the absence of clinical suspicion of an inhaled foreign body. It is the latter group where diagnostic delay may occur, leading to an increased risk of complications.

This study should offer an alert to pediatricians and emergency room staffs that laryngeal foreign bodies should be considered in the differential diagnosis of any young child with acute onset of upper airway symptoms, and as a minimum, specifically enquiring about a history of a choking episode is essential in all young children presenting with acute stridor.