Upper Respiratory Tract Infections in the Critically I11

Abstract

that present in the critically ill (supraglottitis [epiglottitis], deep neck infections, and sinusitis) is presented with attention to pathogenesis, pathophysiology, diagnosis, differential diagnosis, and treatment. Supraglottitis is increasingly diagnosed in adults and, as with children, early recognition is crucial to limit mortality. To aid in diagnosis and treatment, a management algorithm is used. Deep cervical infections, usually extensions of upper airway infections, can spread along fascial planes with fatal results. Knowledge of the interconnections between anatomical spaces is a prerequisite to diagnosis and treatment. Sinusitis will present in the critically ill as orbital or intracranial complications or as a nosocomial infection. Discussions of acute and chronic community-acquired sinusitis in general, nosocomial sinusitis, and sphenoid sinusitis as a separate entity highlight differences in clinical presentation and bacteriology that are important to diagnosis and treatment.The upper respiratory tract consists of the nose, mouth, nasopharynx and oropharynx, hypopharynx. and the paranasal sinuses. While minor infections in these areas are common outpatient entities, they may infrequently become severe and life threatening. It is this class of disease that requires intensive observation and aggressive treatment, and is the focus of this review. Supraglottitis (Epiglottitis). Acute supraglottitis is an uncommon infection of the epiglottis and other supralaryngeal structures, which may progress to abrupt and fatal airway obstruction. The condition is well recognized in children, in whom the presentation and course are usually fulminant. In pediatric age groups, increased awareness and prophylactic airway control have reduced the overall mortality to less than 1% [1]. In adults, however, the course is often more indolent and the mortality approximates 7%, largely due to misdiagnosis and unexpected airway obstruction [2]. Pathogenesis and Pathophysiology. Supraglottitis, the term more recently preferred, since it is more anatomically correct, is an acute, usually bacterial inflammation of the supraglottic structures including the epiglottis, aryepiglottic folds, and arytenoids. The true vocal cords are seldom involved in the process. Since the lingual aspect of the epiglottis in children has a more loose mucosa than in adults, providing an easy space for edema to collect [3], swelling in this area tends to curl the epiglottis posteriorly and inferiorly, accentuating the juvenile &dquo;omega&dquo; shape characteristically seen in children. This swelling reduces the airway aperture [4]. The obstruction increases and respiratory distress occurs when edema spreads and involves the aryepiglottic folds [5]. Inspiration draws these swollen structures downward, thus exacerbating the obstruction and producing stridor [6]. Since the larynx is larger and the epiglottis is shaped less like an omega and more like a &dquo;spatula&dquo; in adults [7], these