The 1998 Paper
Leder, Cohn and Moller investigated the incidence of aspiration following extubation in critically ill trauma patients.
The study looked at 20 patients who required oropharyngeal intubation for at least 48 hours. All FEES were completed around 24 hours following extubation.
Remember, aspiration is when the bolus enters the airway, below the level of the true vocal cords (as defined in this study). Silent aspiration is when there is no accompanying behavior such as a cough or throat clear with aspiration.
During this study, 9/20 (45%) of patients were found to aspirate and 4/9 (44%) were silent aspirators. Silent aspiration was seen in 20% of this population. 8/9 of the patients that aspirated were able to resume an oral diet within 10 days of their initial FEES.
Findings during this study:
- A nasogastric tube was not associated with aspiration.
- Traumatic intubation was noted in 5/20 patients and 4/5 of these patients aspirated.
- Only the Glasgow Coma Scale rating on admission exhibited a significant difference regarding aspiration status. (Low ratings had a higher incidence of aspiration).
- Trauma patients have an increased incidence of aspiration.
The authors suggest that early identification of aspiration following trauma and intubation is indicated to reduce the risk of pulmonary compromise.
There are still many questions following this study, including patients intubated for shorter than 48 hours and which variables impacted aspiration (brain injury, age, traumatic intubation, sedatives, neuromuscular blockers, respiratory status).
Some newer studies indicate:
“Patients aged >55 yrs and those with vallecular stasis on FEES examination were at significantly higher risk of postextubation aspiration. All patients with pneumonia had an associated aspiration episode.”
With prolonged orotracheal intubation, patients are at risk of aspiration following extubation. (Barquist, Brown, Cohn, Lundy and Jackowski)
The incidence of aspiration determined by FEES was 56% and 25% of patients were silent aspirators. The patients found to aspirate were intubated for a mean duration of 8 days, 7.7 days for non-aspirators. 70% of the patients who aspirated thin liquids while 30% aspirated puree. 63% of the patients that aspirated showed improved swallowing and tolerated an oral diet by the time of discharge. (Ajemian, Nirmul, Anderson, Zirlen and Kwasnik)
Instrumental assessments are critical for patients, particularly after intubation 48 hours or longer.
Leder, S. B., Cohn, S. M., & Moller, B. A. (1998). Fiberoptic endoscopic documentation of the high incidence of aspiration following extubation in critically ill trauma patients. Dysphagia, 13(4), 208-212.
Barquist, E., Brown, M., Cohn, S., Lundy, D., & Jackowski, J. (2001). Postextubation fiberoptic endoscopic evaluation of swallowing after prolonged endotracheal intubation: a randomized, prospective trial. Critical care medicine, 29(9), 1710-1713.
Ajemian, M. S., Nirmul, G. B., Anderson, M. T., Zirlen, D. M., & Kwasnik, E. M. (2001). Routine fiberoptic endoscopic evaluation of swallowing following prolonged intubation: implications for management. Archives of surgery, 136(4), 434-437.