Submental surface electromyographic measurement and pharyngeal pressures during normal and effortful swallowing

OBJECTIVE: To evaluate the influence of 2 swallowing maneuvers on anterior suprahyoid surface electromyographic measurement and pharyngeal manometric pressure. DESIGN: Correlational analysis of biomechanic measures of swallowing. SETTING: Research laboratory in a community hospital. PARTICIPANTS: A consecutive volunteer sample of 22 healthy subjects (mean, 29.7y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Peak amplitude of submental surface electromyographic and pharyngeal manometric pressure at 3 locations. RESULTS: Effortful swallow generated greater pharyngeal pressure than normal swallow at the 2 proximal pharyngeal sensors (sensor 1: P=.017; sensor 2: P=.009) and lower pressure at the distal sensor (upper esophageal sphincter) (P<.001). Pressure in the upper pharynx was lower than that in the lower pharynx (P=.027). Effortful swallow generated greater surface electromyographic amplitudes than normal swallowing (P<.001). A statistically significant but weak negative correlation was identified between surface electromyographic and mid-pharyngeal pressure for normal swallowing condition (r=-.21, P<.01). For the effortful swallowing condition, statistically significant but weak negative correlations were identified between surface electromyographic and pressure measurements at all sensors (sensor 1: r=-.16, P=.02; sensor 2: r=-.30, P<.01; sensor 3: r=-.18, P<.01). CONCLUSIONS: There is a significant change in both suprahyoid surface electromyographic and pharyngeal pressures during effortful swallow compared with normal swallow.