Effects of liquid type, delivery method, and bolus volume on penetration-aspiration scores in healthy older adults during flexible endoscopic evaluation of swallowing

Ann Otol Rhinol Laryngol. 2011 May;120(5):288-95. doi: 10.1177/000348941112000502.


Objectives: The type of liquid (eg, water or milk) that should be used during flexible endoscopic evaluation of swallowing (FEES) has received little investigation. Aspiration may vary as a function of the thin liquid type used during FEES.

Methods: We measured the effects of liquid type (water, skim milk, 2% milk, and whole milk; all dyed with green food coloring), delivery method (cup and straw), and bolus volume (5, 10, 15, and 20 mL) on Penetration-Aspiration Scale (PAS) scores in 14 healthy older adults (mean, 75 years; range, 69 to 85 years). Each participant generated 32 swallows.

Results: The PAS scores differed significantly by liquid type (p = 0.003) and by bolus volume (p = 0.017), but not by delivery method (p = 0.442). The PAS scores were significantly greater for 2% milk and whole milk than for skim milk and water (p < 0.05), and for 20 mL versus smaller volumes. Penetration and aspiration were observed on 113 (25%) and 15 (3%) of 448 swallows, respectively.

Conclusions: These findings suggest that both milk and water should be used during FEES for an accurate assessment of aspiration status.

Publication types

  • Comparative Study

MeSH terms

  • Age Factors
  • Aged
  • Aged, 80 and over
  • Deglutition / physiology*
  • Endoscopy, Gastrointestinal / methods*
  • Follow-Up Studies
  • Humans
  • Incidence
  • Manometry
  • Reference Values
  • Respiratory Aspiration / diagnosis*
  • Respiratory Aspiration / epidemiology
  • Risk Factors
  • United States / epidemiology
  • Viscosity