Incidence and type of aspiration in acute care patients requiring mechanical ventilation via a new tracheotomy

Study objectives: To investigate the incidence of aspiration and type of aspiration (overt or silent) in patients requiring mechanical ventilation via a new tracheotomy, ie, within the previous 2 months. Design: Prospective, consecutive. Setting: Urban, tertiary, acute care hospital. Patients: Fifty-two adult inpatients referred for a swallow evaluation between March 1999 and December 2001. Measurements and results: Fiberoptic endoscopic evaluation of swallowing was used to determine incidence and type of aspiration. Aspiration was defined as evidence of food material in the airway below the level of the true vocal folds, with silent aspiration defined as no overt symptoms of aspiration (eg, coughing or choking). Thirty-five of 52 patients (67%) did not aspirate, and 17 of 52 patients aspirated (33%). Fourteen of the 17 patients (82%) who aspirated were silent aspirators. Patients who aspirated were significantly older (mean age, 73 years; range, 48 to 87 years) than those who did not aspirate (mean age, 59 years; range, 20 to 83 years; p < 0.05). Patients who aspirated were posttracheotomy for significantly less time (mean, 14 days; range, 3 to 48 days) than those who did not aspirate (mean, 23 days; range, 1 to 62 days) [p < 0.05]. No significant difference was observed regarding the duration of translaryngeal intubation for aspirators (mean, 14 days; range, 0 to 31 days) vs nonaspirators (mean, 14 days; range, 0 to 29 days; p > 0.05). Conclusions: Two thirds of patients requiring short-term mechanical ventilation via a new tracheotomy swallowed successfully. When aspiration occurred, it was predominantly silent aspiration. It is important to consider age, number of days posttracheotomy, functional reserve, and clinical judgment of recovery rate before performing a swallow evaluation in this population. Specifically, swallowing success will occur most frequently in patients < 70 years old, with optimal timing for a successful swallow outcome at approximately 3 weeks posttracheotoiny in patients > 70 years old and 1 week in patients < 70 years old, and in conjunction with improving medical and respiratory status.