ABSTRACT
Paranasal sinusitis is an important potential cause of fever in the intensive care unit (ICU) (1). The pathophysiology of sinusitis in the ICU setting is similar to that of outpatient sinusitis and is related to obstruction of the osteomeatal complex (OMC), or to disruption of normal mucociliary transport. This is true for the critically ill trauma patient who often has additional risk factors beyond simple inflammatory sinus obstruction, for example, structural injury and disruption of the sinus drainage system. Patients in the ICU often have complicating debilitating medical issues such as nosocomial colonization and immune suppression. Paranasal sinusitis in this setting may lead to severe complications including pneumonia, meningitis, and sepsis (2-5). Thus, when there is clinical concern of sinusitis in the ICU setting, it is evaluated and treated aggressively. This chapter will review the anatomy, pathophysiology, microbiology, diagnosis, and treatment of sinusitis in the critically ill patient. A typical case will be presented to illustrate the key points of diagnosis and treatment.
The paranasal sinuses consist of four paired pneumatized cavities of the skull and facial bones with ostia that drain into the nose (Fig. 1). These are named from top-medial to bottom-lateral as the frontal, ethmoid, sphenoid, and maxillary sinuses. The ethmoid sinuses are unique in that they are composed of 18 to 20 small air cells (like a honeycomb) rather than a single large cavity. The ethmoids are divided into anterior cells, which drain into the middle meatus, and the posterior cells, which drain into the superior meatus. The sphenoid sinus drains via the superior meatus. The frontal, maxillary, and anterior ethmoids all drain via the middle meatus. All of the paranasal sinuses are lined with ciliated pseudostratified columnar epithelial cells (6). The cilia of the sinus mucosa propel a mucus blanket of secretions, bacteria, and purulence toward the ostia. In normal adults, approximately 1500 cc of fluid is produced each day from the epithelium of the nose and paranasal sinuses. Mucociliary transport is estimated to be at a speed of 0.5 cm/min in normal conditions (7). The combination of a large fluid production and a healthy active
