Because of his full recovery, the patient refused a control panendoscopy 6 weeks later.
We report an extreme case of hypopharyngeal injury. To our knowledge, no studies have evaluated patient-related risk factors for hypopharyngeal injury associated with the use of SGAs. However, we suggest the duration of anesthesia and anatomical variations as contributing factors to hypopharyngeal injury. Cuff pressure has been shown to directly correlate with mucosal pressure being greatest in the hypopharynx,3,4 especially opposite the cervical vertebrae.5 Mucosal pressure from the i-gel has been demonstrated to be generally low (5–9.3 cm H2O).4 Historically, the recommended size of SGAs is based on weight. In this case, despite the patient’s moderate weight of 71 kg (size 171 cm), a size #5 i-gel was used, which was larger than recommended. Recent evidence suggests that the correct size of an SGA depends not only on weight, but also on height, age, and gender.1 However, in the case of the i-gel, perhaps a more prudent approach to achieving a proper size would be to choose the smallest size providing an effective seal.
DISH is a degenerative disease of unknown origin, more common in men than women. Even though often asymptomatic and therefore not detected, dysphagia, airway obstruction, and dysphonia can be found in patients having DISH. However, symptoms are rarely severe or even life threatening.6,7 Studies suggest that the prevalence of DISH ranges from 10% to 35% among patients aged >50 years.8 The prevalence of airway complications from DISH, however, is unknown. Anterior displacement of the larynx with subglottic stenosis and bulging of the pharyngeal wall is reported to cause difficult tracheal intubation associated with DISH.9–12 In these case reports, the distortion of the pharyngeal anatomy creating the difficulties in airway management during the anesthesia intervention was caused by ventral cervical osteophytes compressing the pharyngeal wall and secondary tissue inflammation.
Among the many predictors for difficult intubation, little attention is directed toward the anatomy of the patient’s cervical spine.13 If tracheal intubation fails, difficult airway management guidelines include the use of SGAs.14,15 Unfortunately, recently published risk factors for difficult SGA ventilation overlap with risk factors for difficult mask ventilation and difficult laryngoscopy, such as impaired mandibular subluxation and old age.1,16 Published evidence does demonstrate limited mouth opening, oropharyngeal pathology, and restricted atlanto-occipital joint extension (oropharyngeal angle <90°) to be important factors that make laryngeal mask airway (and most likely other SGAs as well) placement difficult.17 Additionally, a reduced range of motion may suggest otherwise undiagnosed pathologies such as DISH. Considering the frequent prevalence for DISH and other rheumatologic diseases in older patients, high suspicion for potential adverse events caused by spondylophytes that may not be diagnosed through standard diagnostic tests may be warranted. If cervical spine imaging is available, reviewing those images should be considered as part of the airway work-up. Our case demonstrates that cervical anatomy influences the performance of SGAs not only because of reduced range of motion of the neck that may lead to difficult placement, but also because of spondylophytes leading to serious adverse outcomes.
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