PROJECT SUMMARY/ABSTRACT
Each year more than 700,000 patients survive an episode of acute respiratory failure (ARF) that required
endotracheal intubation with mechanical ventilation. Occurring in as many as 44% of these ARF survivors,
post-extubation aspiration is associated with deleterious consequences including pneumonia, percutaneous
feeding tube placement, long term care facility admission, and increased hospital mortality. Nevertheless, the
complications of aspiration must be weighed against the consequences of inappropriately delaying the
resumption of oral feeding. Delayed resumption of oral nutrition is associated with prolonged enteral tube
feeding, increased caregiver burden, patient dissatisfaction, and increased health-related costs. With the
support of an NINR R21 award, our multidisciplinary and multicenter team discovered three novel findings: 1)
we developed a 5-item screening decision tree algorithm that detects patients at high risk for post-extubation
aspiration; 2) we identified certain unique upper airway abnormalities that are associated with post-extubation
aspiration and dysphagia; and 3) the size of the endotracheal tube (ETT) is independently associated with
post-extubation aspiration. This proposal will continue to utilize our robust and established multi-center
research group at Colorado, Boston University, Stanford, and Yale; all of whom have long-standing dysphagia
and aspiration research groups focused on ARF. We will conduct a multi-center cohort study with three
complementary aims that are interrelated and use the same patients; but are not dependent upon the results of
each other. Aim #1 will determine whether our 5-item decision tree algorithm is a more effective screening tool
to identify patients at high risk for post-extubation aspiration compared to the three-ounce water swallow test
(3-WST) and the Toronto Bedside Swallowing Screening Test (TOR-BSST). These results will establish the
optimal screening test for post-extubation aspiration and identify those patients who require further invasive
diagnostic testing such as a FEES examination. Aim #2 will identify unique subphenotypes of patients with
post-extubation aspiration based upon FEES-related measures of upper airway structure and function. Using a
novel latent class analysis, we will determine whether these subphenotypes are associated with different
trajectories of recovery and identify unique patients who benefit from different personalized and targeted
therapies. Aim #3 will determine the association between ultrasound determined ETT size/tracheal diameter
ratio and post-extubation aspiration while accounting for other confounding variables. This aim will identify the
most effective method to select the ETT size that optimizes ventilatory management and decreases post-
extubation aspiration. The results of this aim will pave the wave for dramatic improvements in the intubation
process for all ARF patients who require mechanical ventilation. With an innovative and protocolized approach,
the results of this proposal will demonstrate novel methods to minimize post-extubation aspiration, transform
the multidisciplinary care of ARF survivors, and improve patient outcomes and quality of life.