The feasibility of assessing swallowing physiology following prolonged intubation after cardiovascular surgery

Stacey A. Skoretz, Terrence M. Yau, John T. Granton, Rosemary Martino

Dysphagia following prolonged intubation after cardiovascular (CV) surgery is common occurring in 67% of patients; however, this population's swallowing physiology has never been prospectively evaluated using standardized methods. Hence, prior to conducting a larger study, our primary objective was to determine the feasibility of assessing swallowing physiology using instrumentation and validated interpretation methods in cardiovascular surgical patients following prolonged intubation. From July to October 2011, we approached adults undergoing CV surgery at our institution who were intubated > 48 h. Those with a tracheostomy were excluded. Videofluoroscopic swallowing study (VFS) and nasendoscopy were completed within 48 h after extubation. Feasibility measurements included recruitment rate, patient participation, task completion durations, and the inter-rater reliability of VFS measures using the intraclass correlation coefficient (ICC). VFSs were interpreted using perceptual rating tools (Modified Barium Swallow Measurement Tool for Swallow Impairment™© and Penetration Aspiration Scale) and objective displacement measurements (hyoid displacement and pharyngeal constriction ratio). Of the 39 patients intubated > 48 h, 16 met inclusion criteria with three enrolled and completing the VFS. All refused nasendoscopy. Across all VFSs, rating completion time ranged from 14.6 to 51.7 min per patient with ICCs for VFS scales ranging from 0.25 (95% CI - 0.10 to 0.59) to 0.99 (95% CI 0.98 to 0.99). This study design was not feasible as recruitment was slow, few patients participated, and no patient agreed to all procedures. We discuss necessary methodological changes and lessons learned that would generalize to future research.