With airway obstruction, trauma, or elective surgery, control of the airway is the first priority that must be accomplished before any other intervention can proceed. In cases of a rapidly decompensating airway, particularly in pediatric patients or patients with airways that are difficult to manage, the otolaryngologist is frequently consulted to assist in patient airway management.
Successful airway management must begin with a careful, thorough, and rapid evaluation of the airway. Healthy patients presenting with normal head and neck anatomy who undergo elective surgery represent relatively straightforward cases in which standard endotracheal intubation can provide an easy and secure airway. Patients presenting with upper airway obstruction must be evaluated quickly, efficiently, and accurately.
Physical examination is a key element in diagnosing upper airway obstruction. Stridor, or noisy respiration, is a hallmark symptom of upper airway obstruction. The timing of the stridor with respiration can frequently indicate where the obstruction lies. Inspiratory stridor normally results when the obstruction is at the larynx or above. Expiratory stridor usually indicates a more distal obstruction (eg, a tracheal obstruction). Biphasic stridor (ie, noise on both inspiration and expiration) may indicate a subglottic obstruction. The quality of the voice is also important. A muffled voice may reflect supraglottic obstruction, such as from the epiglottitis. A hoarse voice may indicate laryngeal involvement (eg, papillomas or tumors). A breathy or weak voice or cry may suggest vocal cord paralysis. Other signs of upper airway obstruction include suprasternal or substernal retractions, tachypnea, and cyanosis.
An accurate history is also critical in evaluating the airway and formulating the best plan to manage it. The physician should determine whether the obstruction occurred acutely or chronically. The age of the patient also helps in distinguishing the cause of the obstruction. Congenital airway anomalies (eg, laryngomalacia, choanal atresia, hemangioma, and tracheomalacia) and acute inflammatory causes (eg, croup and epiglottitis) are more common in children. In adults, tumors are a more common cause of obstruction. Trauma can cause airway obstruction, and this circumstance is usually easy to diagnose. However, it is important to carefully ascertain the mechanism and type of injury. Suspicion of laryngeal trauma may make conventional endotracheal intubation perilous because it can potentially result in a more compromised airway due to laryngotracheal separation. In these circumstances, the physician should consider performing a tracheotomy while the patient is awake. Similarly, massive maxillofacial trauma may preclude normal translaryngeal intubation; a flexible fiberoptic intubation or a tracheotomy while the patient is awake should be considered in these situations.
Patients with difficult airways should be identified before the induction of anesthesia and intubation so that proper planning and communication between the anesthesiologist and the surgeon can be coordinated. A difficult airway is defined as a situation in which a conventionally trained anesthesiologist experiences difficulty with mask ventilation, endotracheal intubation, or both. In addition, the physician should be prepared for a potentially difficult airway or ...