Pediatric Epiglottitis Workup

Securing an airway is the overriding priority. An expert in pediatric airway management should always perform an endotracheal intubation on any child with suspected epiglottitis before radiography or blood work is performed.

Laryngoscopy is the best way to confirm the diagnosis, but it is not advised to attempt any procedures without securing the airway. Simply depressing the child's tongue with a tongue blade may visualize the epiglottitis in some situations. Some concern exists regarding the safety of such procedures, which can provoke anxiety and increased respiratory effort during examination leading to airway obstruction.

Laboratory evaluation is nonspecific in patients with epiglottitis and should be performed once the airway is secured. The white blood cell (WBC) count may be elevated from 15,000-45,000 cells/µL with a predominance of bands. Histologic examination reveals massive infiltration with polymorphonuclear leukocytes and inflammatory edema.

Classic cases of epiglottitis require no radiographic evaluation; however, radiography may be needed in some cases to confirm the diagnosis and to exclude other potential causes of acute airway obstruction. When radiography is required to exclude other diagnoses, perform portable radiography at the patient's bedside.

Recommendations for computed tomography (CT) scanning of the neck in early or unusual cases have been suggested, ^[15] although great care should be used because of the positioning of the patient.

If epiglottitis is in the differential diagnosis, the child should never be left alone even if imaging studies are being obtained. The child should always be accompanied by personnel who are able to achieve rapid airway access if needed.

Blood cultures and culture of the epiglottis should be performed only after the airway is secured.

Blood cultures may show Haemophilus influenzae type b (Hib) between 12-15% and 90% of cases.

Cultures of the surface of the epiglottis obtained during endotracheal intubation are positive in 50-75% of cases. ^[16]

If epiglottitis is seriously considered, no imaging studies are required. In less-clear cases, imaging studies are occasionally helpful in establishing the diagnosis or excluding epiglottitis.

Lateral neck radiography

Never obtain a lateral neck radiograph before achieving definitive airway control. If radiography is required, the safest procedure is to perform portable radiography at the bedside.

In classic epiglottitis, a lateral soft-tissue radiograph of the neck reveals a swollen epiglottis protruding from the anterior wall of the hypopharynx (ie, thumbprint sign), ^[17] thickened aryepiglottic folds, obliteration of the vallecula, and dilation of the hypopharynx (see the following images). Note that negative findings on lateral radiographs do not exclude the diagnosis, especially in the early stages of presentation.

Swollen epiglottis with characteristic thumbprint sign.

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Radiograph of a child with acute epiglottitis; note the hypopharyngeal dilatation, obliteration of the vallecula, and thickened aryepiglottic folds—a positive thumb sign.

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Chest radiography

Chest radiography may reveal concomitant pneumonia in as many as 15% of patients. Postintubation chest radiographs occasionally show pulmonary edema.

Laryngoscopy can help exclude other diagnoses in an older child who is cooperative. However, do not perform a laryngoscopy if the procedure might increase anxiety, which can exacerbate the airway obstruction.

The naris can be anesthetized with lidocaine jelly before inserting the fiberoptic laryngoscope. Insert the laryngoscope through the naris, advancing it slowly into the supraglottic region. The epiglottis should be easily visualized to determine the presence of swelling.

A study performed in Germany recommended laryngoscopy to aid in the diagnosis in patients with atypical presentations or with crouplike coughs. This study also showed that fiberoptic endoscopy is especially useful in cooperative older children with moderate respiratory distress.

Also termed needle cricothyrotomy or translaryngeal ventilation, percutaneous transtracheal ventilation is a temporizing method used to treat cases of severe epiglottitis when the patient cannot be intubated before a formal tracheostomy.

Percutaneous transtracheal ventilation involves inserting a needle through the cricothyroid membrane, which lies inferior to the thyroid cartilage and superior to the cricoid cartilage. The cricothyroid arteries typically course through the superior portion of the membrane.

The procedure is performed as follows:

• Begin by localizing the cricothyroid membrane. This can be accomplished by finding the thyroid cartilage prominence (ie, Adam's apple) and running a finger down until the depression of the cricothyroid membrane is felt. Another method is to find the trachea and run the fingers up along the tracheal rings until a more prominent bulge representing the cricoid ring is felt; the cricothyroid membrane is above this bulge. The latter technique has been shown to be more useful in small infants.

• Prepare the membrane area with antiseptic solution. If the patient is awake, use lidocaine to anesthetize the skin overlying the membrane.

• Use the thumb and middle finger of the nondominant hand to hold the trachea in place. In the dominant hand, hold a 3-mL or 5-mL syringe containing 2 mL of saline or lidocaine, which is attached to the needle and 16-gauge or 18-gauge catheter.

• Place the needle through the inferior portion of the cricothyroid membrane at the midline, caudally directing the needle at a 45° angle, and puncture the skin and subcutaneous tissue. A small incision with a No. 11 scalpel facilitates needle and catheter insertion.

• Apply continuous negative pressure while advancing the needle. The needle should be inside the trachea when bubbles become visible in the syringe.

• Advance the catheter off the needle until its hub rests against the skin surface. Remove the needle and syringe.

• Connect high-pressure tubing to the catheter and administer 100% oxygen at 25-35 pounds per square inch for small children.

Perform ventilations at a rate of 1 second of inhalation to 4-5 seconds of exhalation. Exhalation is easily accommodated by cutting a small hole in the distal end of the high-pressure tubing to create a side hole. Inhalation occurs when the hole is covered with a finger, exhalation when the hole is left open.