Swallow respiration patterns in dysphagic patients following acute stroke

The aim of this study was to examine swallow respiratory characteristics using a notebook computer system. A relatively simple system assessing easily identifiable features is more likely to be incorporated into everyday clinical practice. Eighteen patients (age range = 51-82 years) with dysphagia poststroke and 50 healthy volunteers (age range = 20-78 years) were recruited. The patient group was less likely to always breathe out post-swallow on water (9/15 of 46/49), and some did not breathe out immediately postswallow at all (3/15 of 0/49, p < 0.01). The pattern was similar with yogurt. Multiple swallowing was identified in the patient group and surprisingly with a large number of the volunteers for all bolus types but was more common in the patient group (p < 0.01). This trait is usually attributed to impaired swallows; that it is prevalent in the normal population has implications for using it as a dysphagia marker in clinical assessments. Yogurt has intrinsic features that increase multiple swallowing and caution should be used when identifying an impairment based on multiple swallowing with such a test substance. In the control group there was a high correlation of swallow apnea on 5 mL of water compared with 20 mL of water (r = 0.759, p < 0.01) and 5 mL of yogurt (r = 0.871, p < 0.01), indicating a possible individual swallow respiration pattern. This was also evident in the patient group. No significant difference in length of swallow apnea was found between the two groups. No evidence was found to link swallow respiration characteristics with aspiration as identified on simultaneous videofluoroscopy. The patient group had a wide range of impairments which suggests that stroke severity is not the sole determinant of swallow respiratory changes.