Evidence-Based Diagnosis and Management of ENT Emergencies

Michael Winters, MD

Disclosures

February 15, 2007

Introduction

Emergency physicians (EPs) diagnose and treat a variety of ear, nose, and throat (ENT) disorders on a daily basis. Although the majority of these conditions are benign, there are several critical ENT disorders that must be immediately recognized and treated. The following article discusses these potentially life-threatening ENT conditions, namely, acute epiglottitis, angioedema, malignant (necrotizing) otitis externa (MOE), Ludwig's angina, and tracheoinnominate (TI) fistula. In recent years, numerous reviews, trials, and recommendations have been published that have advanced the understanding of the pathophysiology and clarified the appropriate diagnostic work-up and management of these conditions. With this information, the EP can more effectively recognize these disorders and provide current, evidence-based treatment.

Although still debated by some historians, it is believed that George Washington died from a case of acute bacterial epiglottitis.[1] In fact, his is probably the first recorded death from this disorder.[2] Epiglottitis is defined as inflammation of the epiglottis, most often due to an infectious etiology. Rapid airway obstruction can result from progressive inflammation and edema of the epiglottis. Mortality rates for epiglottitis range from 7% to 20% in adults and are directly related to the development of airway obstruction.[2,3] Thus, urgent diagnosis and treatment are essential. Unfortunately, delays in diagnosis are common. It is estimated that epiglottitis is missed by primary care physicians in all but 35% of cases.[2,4]

Early descriptions of epiglottitis consisted primarily of case reports in the adult population.[2] Since the 1960s, however, epiglottitis has been described as largely a childhood disease. Then, with the widespread application of the Haemophilus influenzae type b vaccination, the incidence of the disease in the pediatric population markedly declined.[2,5,6] As a result of this decline, acute epiglottitis is now more common in adults, and not only is it more common in adults; recent reports indicate that the incidence is rising.[7,8] The current annual incidence of epiglottitis in adults ranges from 1.0 to 3.1 per 100,000 persons per year.[7,8] The average age at presentation ranges from 42 to 50 years, with the peak incidence occurring from ages 35 to 39.[3,9] Depending on the study, there is a slight male predominance that ranges from 2:1 to 4:1.[2,10,11]

The most common cause of acute epiglottitis is infection. A variety of bacteria have been implicated in the disease. The most common bacteria identified include H influenzae, beta-hemolytic Streptococcus, Staphylococcus aureus, and Streptococcus pneumoniae.[3] Although viruses are considered by many to be a common cause, only herpes simplex has been positively identified on histologic specimens.[2,12] Patients with immunosuppressive conditions, such as those with HIV, are at risk for infection from atypical organisms. Atypical organisms linked to epiglottitis in the immunocompromised population include Aspergillus, Candida, and Klebsiella.[2,13] In many cases, a causative organism is not isolated.

In addition to infection, there are a number of noninfectious etiologies of epiglottitis. Perhaps most important is the development of epiglottitis from thermal inhalation injury. Recent reports have illustrated the inhalation of crack cocaine as an etiology of noninfectious epiglottitis.[14,15] Additional noninfectious etiologies include neck trauma and caustic ingestions.[3,16]

The clinical presentation of epiglottitis in adults is different from that in children. In contrast to children, adults are less likely to present with dyspnea, drooling, stridor, or fever. Adults are more likely to report severe sore throat, odynophagia, and hoarseness. In fact, the combination of severe sore throat and odynophagia is present in over 90% of adults with epiglottitis.[3] Delays in presentation are common. Typically, adults present an average of 2 days after the onset of symptoms.[3] Carefully exam the neck in adults with severe sore throat. Up to 80% of adults with epiglottitis have marked anterior neck tenderness on physical examination.[8,17,18] Suspect epiglottitis in any adult with severe sore throat, odynophagia, and tenderness of the larynx.

The gold standard for diagnosis is direct visualization of the epiglottis and surrounding structures. Direct visualization is accomplished through laryngoscopy. In contrast to children, indirect laryngoscopy is considered a safe procedure in adults with suspected epiglottitis.[2] Fiber-optic nasopharyngeal laryngoscopy (NPL) can also be used to visualize the posterior elements of the hypopharynx, including the epiglottis. It is important to recognize that radiographs are of limited value. Depending on the study, the overall sensitivity of plain films for epiglottitis can be as low as 75%.[3] The classic radiographic finding is swelling of the epiglottis on lateral soft-tissue neck x-ray, commonly referred to as the "thumb sign". This sign is absent in 14% to 27% of cases.[3] In a recent study, Ducic and colleagues[19] described the "vallecula sign". The vallecula sign is characterized by a decrease in the vallecular air space as the epiglottis swells.[9] With appropriate training, the investigators were able to diagnose epiglottitis with plain films with 98.8% accuracy.[19] Although promising, the initial study involved only a small number of positive plain films, and further study is needed before widespread clinical application. Arterial blood gas analysis and the white blood cell count are nonspecific and of no diagnostic or prognostic value in epiglottitis.

Once the diagnosis is confirmed, treatment centers on airway management and prompt antibiotic administration. Up to one third of patients with epiglottitis eventually require endotracheal intubation.[9] Any patient with respiratory distress should be immediately intubated. Recognize that intubation is often difficult due to significant swelling of the epiglottis and surrounding structures, and any attempts at blind intubation must be avoided. Up to 15% of patients in whom blind intubation is attempted require emergent tracheotomy.[9,17] For patients without respiratory distress, the literature is less clear. A number of retrospective reviews have attempted to identify clinical features that predict airway deterioration. Unfortunately, there is no particular sign or combination of signs that has been shown to consistently identify patients who will require airway support.[3] For patients who are being observed, always have equipment for intubation and cricothyroidotomy available at the bedside.

The majority of adults with epiglottitis will respond to medical management with antibiotics and close observation. Current recommendations are that patients receive a second- or third-generation cephalosporin with activity against H influenzae.[2,3] At present, there are no controlled trials that demonstrate the benefit of aerosolized racemic epinephrine, corticosteroids, or humidified air. Given the potential for airway compromise, all patients with epiglottitis require admission to an intensive care unit (ICU).

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