Initial Screening Tests to Predict Prognosis of Dysphagia

Abstract

[Purpose]　This study examined whether initial screening tests for dysphagic patients in an acute care hospital can predict the recovery of oral intake. We also analyzed risk factors associated with silent aspiration (SA) that bedside screening tests sometimes fail to detect due to absent outward signs such as coughing or choking.

[Subjects and Methods]　We retrospectively analyzed 314 dysphagic patients (average age 67.1 years) who were treated by speech-language-hearing therapists during 2007 and 2008. The initial examinations used to test swallowing function were the Repetitive Saliva Swallowing Test (RSST) and the Modified Water Swallowing Test (MWST). We divided the patients into two groups based on their dietary status at discharge: 1) good outcome patients who regained full oral intake and 2) poor outcome patients who required tube feeding. We compared the good outcome group to the poor outcome group using the initial examination results of RSST and MWST together with consciousness levels at the start of training, the Dysphagia Severity Scale, presence/absence of tracheotomy, videofluoroscopy (VF) findings, videoendoscopy (VE) findings and aspiration/SA.

[Results]　One hundred eighty-seven patients (59.6%) had good outcomes, whereas 127 patients (40.4%) had poor outcomes. The good outcome patients had a younger average age and clearer consciousness. Of patients with RSST ≥ 3 times/30 seconds and MWST score ≥ 3, 87.9% regained full oral intake. On the other hand, 7.5% of those with MWST score of 4 and 6.8% of those with MWST score of 5 were overestimated despite having SA. Diagnoses among the SA group include pseudobulbar palsy, post-thoracotomy, head and neck cancer treated with chemoradiation, brainstem lesions, degenerative neurologic disease, and dermatomyositis. Other SA risk factors were associated with pneumonia before training (n＝25), vocal fold paralysis (n＝14), and tracheotomy (n＝16).

[Conclusion]　This study found that RSST and MWST were useful screenings for swallowing disorders and also could predict the recovery to oral intake within acute care hospitalization days. Screening tests for dysphagia require attention to the risk factors of SA; and patients with suspected SA should be examined with VF or VE before the start of oral intake.