Epiglottitis is one of the diseases whose epidemiology has been drastically changed by immunizations. Anyone practicing emergency medicine for more than five years probably remembers learning the scenario in which a young child is brought to the ED with a fever, drooling, and stridor. Although even then a rare occurrence, it is viewed as one of those pulse-elevating events in the ED.
Although I personally have never managed a child with epiglottitis, I can recite the management scenario in my head. I have, however, managed more than a few adults with epiglottitis, a patient much less pulse-elevating but more common these days.
Epiglottitis is defined as any inflammation of the epiglottitic and supraglottic area, which also may include the aryepiglottic folds, arytenoids, pharynx, and uvula. Although infectious agents are the most common etiology, mechanical injury such as inhalation of hot or caustic materials also has been reported. (J Emerg Med 1997;15:483.)
In children, epiglottitis is fairly obvious, but adults generally look less ill
Haemophilus influenzae type b is known as the predominant infectious cause, but Streptococcus species, Staphylococcus aureus, and H. parainfluenzae are also known agents. (Acad Emerg Med 2004;11:1358.) Children have an incidence of bacteremia of approximately 90 percent to 100 percent, but adults have a much lower positive blood culture rate (20%-30%). (Chest 1997;112:1419; Laryngoscope 1998;108:64; Am J Emerg Med 1996;14:421.)
Since the Hib vaccine was released in 1985, the incidence of epiglottitis in children has drastically decreased from 3.5 cases per 100,000 to 0.6 cases per 100,000. The most recent epidemiological studies are all showing trends toward a lower incidence of pediatric cases and rising incidence of adult cases. (Am J Otolaryngol 2003;24:374; Pediatrics 1995;96:424.) There also are many documented cases of vaccine failure with the now-discontinued purified polysaccharide vaccine; these will generally be the pediatric cases one may currently encounter.
The diagnosis of epiglottitis begins with clinical suspicion. In children, it is often fairly obvious, but in adults, who generally look less ill, one must count on a combination of clinical suspicion and studies to confirm the diagnosis. The most predominant symptoms in adults and children are sore throat and odynophagia.
Other symptoms, all which present much less universally, are respiratory distress, muffled voice, and drooling. It has been noted that the presence of stridor, dyspnea, and a short duration of symptoms trend toward airway loss in adults. (Am J Emerg Med 1996;14:421; Laryngoscope 1998;108:64.)
If the patient (adult or child) is clinically stable, the work-up should begin with a soft tissue lateral neck radiograph. Traditionally, a thickened epiglottis, resulting in the “thumbprint” sign, is used as the radiographic sign for epiglottitis. More recently, however, the “vallecula sign,” reported by Ducic, et al (Ann Emerg Med 1997;30:1) was shown to increase accuracy of the soft tissue neck radiograph. This finding, in which there is no obliteration of the vallecula (the air pocket just anterior to the epiglottis), was found to be 98.2% sensitive (rules out epiglottitis). It was found to be easily taught and reproducible in their study.
The next step in diagnosis is usually direct visualization, either by indirect laryngoscopy or NPL. Certainly most would agree that if available, NPL is an easier method of visualization. A swollen, bright red epiglottis confirms the diagnosis. CT and MRI also have been used to confirm the diagnosis, and interestingly, a study (Acad Emerg Med 2004;11:1358) showed that ultrasound can reliably visualize and measure the epiglottis. This report from Pittsburgh did not include patients with epiglottitis; it only considered whether the modality is feasible to visualize the structure.
The management continues with airway considerations, and here is where the disease differs. In children, the ED course should consist of calls to anesthesia and ENT, leaving the child in his most comfortable position. I also suggest having a surgical airway setup nearby. In adults, the literature and experience relating to airway compromise is conflicting.
Three case reports (all adults) describe airway loss in all three patients (Brit J Anaesthesia 2000;85:795), but a larger sample (129 patients) reported only a 15 percent intubation rate. The recommendation from the latter paper is that unless the adult patient is exhibiting signs of upper airway compromise, ICU admission without intubation is reasonable. (JAMA 1994;272:1358.)
The mainstay of treatment is antibiotics. A third-generation cephalosporin is the agent of choice with TMP/SMX as the alternative, although many use ampicillin-sulbactam. Steroids and inhaled epinephrine have not been proven to provide any benefit, but there is at least one European case report in which a single patient improved after inhaled epinephrine and intravenous steroids. (Ann Fr Anesth Reanim 2004;23:1003.)
Reviewing the European literature, it seems that they feel inhaled steroids and epinephrine are reasonable treatment options, in contrast to here in North America, where it does not seem to be. There is also the recommendation that all children under 4 in the household of the patient be prophylaxed with rifampin. (Brit J Anaesthesia 2000;85:795.)