ACUTE epiglottitis is a serious infection of the supraglottic structures, which carrier the potential for lethal, total airway obstruction necessitating urgent airway management. In epiglottitis, a protocol that involved tracheal intubation after administration of general anesthesia induced by inhalation anesthetic has been recommended. [1]However, the airway obstruction may worsen or become complete as the patient becomes anesthesized or when the airways are manipulated. Sevoflurane has been reported to have a minimal effect on respiratory mechanics, with little airway irritation when used for anesthesia induction. [2]We described three case of epiglottitis necessitating urgent airway management in which tracheal intubation was performed successfully during administration of sevoflurane inhalation anesthesia.

Case 1

A previously healthy, 15-yr-old boy was first admitted to a local hospital for hoarseness and difficulty in swallowing with no respiratory symptoms. With rapidly progressing symptoms, he was transferred to our institution. At admission he was distressed, unable to speak, had difficulty swallowing, and had moderate difficulty breathing while in the sitting position and while leaning forward. His temperature was elevated (38 [degree sign]C), but his erythrocyte count was normal. Indirect laryngoscopy revealed a large, swollen epiglottis. Glycopyrrolate (0.2 mg) was administered intravenously, and the patient was transferred to the operating room. He was placed in a semisitting position. Anesthesia was induced by mask inhalation of high concentration of sevoflurane (up to 5%) in 100% oxygen through a Bain circuit. Spontaneous breathing was sustained. When relaxation for intubation was adequate, a size-6 endotracheal tube was passed through an extremely swollen arytenoid region and edematous epiglottis oratracheally. After taking blood and throat culture samples, intravenous cefuroxime (1.5 g x 3) was administered. Subsequent to intubation, he was transferred to the intensive care unit.

Case 2

A 40-yr-old, otherwise healthy man was admitted to the emergency room. He had a sore throat, fever, and progressive difficulty breathing for 3 days. At admission his temperature was elevated (39 [degree sign]C), he was unable to swallow, and he used his accessory muscles for breathing. During indirect laryngoscopy, his epiglottis was extensively swollen. After glycopyrrolate (0.2 mg) was administered intravenously, anesthesia was induced while the patient was in the sitting position using a high concentration of sevoflurane (up to 7%) and 100% oxygen. The patient was slowly assisted to a supine position and a size-6.5 endotracheal tube was introduced through the swollen and edematous arytenoids and epiglottis oratracheally. The patient was transferred to the intensive care unit.

Case 3

An obese, 54-yr-old woman with a history of hypothyroidism was admitted with a sore throat, a high fever, and progressive difficulty breathing. She was sitting, leaning forward, using all her accessory respiratory muscles, was drooling, was unable to swallow, had inspiratory stridor, and her speech was hoarse. After a sevoflurane induction performed in a fashion similar to the previous cases, a size-7 endotracheal tube was inserted uneventfully using direct vision through the swollen arytenoids and epiglottis. The patient was transferred subsequently to the intensive care unit.

Halothane previously has been recommended as the inhalation anesthetic of choice in the airway management of epiglottitis patients. [1]Similar to enflurane, isoflurane, and desflurane, however, its major disadvantage is a strong odor that frequently is associated with coughing and laryngospasm. [3,4]It has been shown that induction with sevoflurane is smoother and is associated with less coughing and holding of breath than that with halothane. [5]It is also less arrhythmogenic than halothane, which could be advantageous in cases of respiratory distress with elevated cathecolamines. [6]In these patients, sevoflurane provided a smooth induction without airway irritation while maintaining spontaneous respiration and providing good relaxation for tracheal intubation.

The airway management for adult patients with mild or no respiratory symptoms is controversial. [7,8]A recent retrospective review suggests that routine prophylactic intubation appears to be unnecessary for adult patients with acute epiglottitis without severe respiratory distress. [8]In the first patient, conservative treatment was judged to be inadequate because his respiratory symptoms rapidly progrediated during observation in another institution. Patients 2 and 3 had severe respiratory distress when admitted, and urgent establishment of a patient airway was indicated because total obstruction was imminent. Meticulous planning of the airway management should be performed before manipulation. Routine elective intubation in patients with acute epiglottitis carries a high risk for complete airway obstruction. If conservative management is chosen, it must be accompanied by careful monitoring for possible respiratory compromise and by personnel skilled in airway management.

Patients with potentially difficult airway may benefit from the maintenance of spontaneous breathing and airway patency until laryngoscopy and tracheal intubation are accomplished successfully. The avoidance of apnea with the use of sevoflurane, often induced with intravenous anesthetics, will ensure unblocked airways. [9]Conversely, as with other inhaled anesthetics, sevoflurane is a ventilatory depressant for which effects have been observed to be more pronounced than that with halothane. [10]It has been suggested that very induction with sevoflurane consequent to low blood/gas solubility may result in significant hypoventilation, leading to apnea rapidly deteriorating a compromised airway. [11]By limiting the concentration of sevoflurane to 5-7% in 100% oxygen in these patients, induction was gradual (approximately 2-3 min), which ensured that sudden ventilatory depression was avoided. Conversely, sevoflurane is redistributed slowly from the blood to the tissues because of its low tissue/blood solubility. [11]Therefore, anesthesia induction will be prolonged in cases of severe hypoventilation or apnea that could cause problems if ventilation is not possible. Spontaneous ventilation was preserved in all the patients, and they were intubated rapidly by experienced laryngoscopists with no major difficulties. Induction and intubation were accomplished in all three patients within 5 min.

The major advantages of sevoflurane compared to halothane or other agents in cases of epiglottitis are that there is significantly less airway irritation in a situation in which the patient is very agitated and prone to coughing and laryngospasm. If not recognized, however, the low solubility of sevoflurane may pose a serious disadvantage in managing these cases because it may lead rapidly to deep anesthesia, hypoventilation, apnea, and sudden loss of airway patency.

Warner JA, Finaly WE: Fulminating epiglottitis in adults, Anaesthesia 1985; 40:348-52.
Green WBJ: The ventilatory effects of sevoflurane. Anesth Analg 1995; 81:S23-6
Smith I, Nathanson M, While P: The role of sevoflurane in outpatient anesthesia. Anesth Analg 1995; 81:S67-72.
Patel S, Goa K. Sevoflurane: A review of its pharmacodynamic and pharmacokinetic properties and its clinical use in general anesthesia. Drugs 1996; 51:658-700
Doi M, Ikeda K: Airway irritation produced by volatile anaesthetics during brief inhalation: Comparison of halothane, enflurane, isoflurane and sevoflurane. Can J Anaesth 1993; 40:122-6.
Paris ST, Cafferkey M, Tarling M, Hancock P, Yate PM, Flynn PJ: Comparison of sevoflurane and halothane for outpatient dental anaesthesia in children. Br J Anaesth 1997; 79:280-4
Crosby E, Reid D: Acute epiglottis in the adult: Is intubation mandatory? Can J Anaesth 1991; 7:914-8
Park KW, Darvish A, Lowenstein E: Airway management for adult patients with acute epiglottitis. A 12-year experience at an academic medical center (1984 - 1995). Anesthesiology 1998; 88:254-61
Thwaites A, Edmends S, Smith I: Inhalation induction with sevoflurane: A double blind comparison with propofol. Br J Anaesth 1997; 78:356-61
Doi M, Ikeda K: Respiratory effects of sevoflurane. Anesth Analg 1987; 66:241-4
Fenlon S, Pearce A: Sevoflurane induction and difficult airway management (letter). Anaesthesia 1997; 52:285-6