Scope and Impact of the Problem
Critically ill patients are at increased risk of aspirating oropharyngeal secretions and regurgitated gastric contents. For those who are tube-fed, aspiration of gastric contents is of greater concern. Diagnosis of aspiration is difficult without the use of costly procedures; thus, the incidence of this condition is unclear. However, aspiration is clearly a common problem in acutely ill patients. For example, videofluoroscopically documented aspiration was reported in 42.6% of 1100 hospitalized adults (25% of the patients were aspirating silently).1 In a laboratory study (using pepsin as a marker for aspiration of gastric contents), frequent microaspirations were identified in approximately half of 360 critically ill patients undergoing mechanical ventilation who were receiving tube feedings.2 In the same study, risk for pneumonia was about 4 times greater in patients identified as frequent aspirators. Reportedly, aspiration pneumonia represents 5% to 15% of pneumonias in the hospitalized population.3 Because no bedside tests are currently available to detect microaspirations, efforts to prevent or minimize aspiration take on added importance.