Effects of Sensory Neuromuscular Electrical Stimulation on Swallowing in the Elderly Affected by Stroke

Abstract

Background: Few studies show the effectiveness of neuromuscular electrical stimulation (NMES) in the rehabilitation of neurogenic dysphagia. Objective: To evaluate the effect of sensory NMES on swallowing in elderly patients with stroke sequelae. Methods: Ten poststroke elderly patients were submitted to swallowing video fluoroscopy, from which the degree of oropharyngeal dysphagia was ranked through the Dysphagia Outcome and Severity Scale, measured from the oral and pharyngeal transit times and classified in residue scale, including the application of the swallowing-related quality-of-life protocol, SWAL-QOL, before, immediately, and after 3 months of rehabilitation. The treatment sessions were performed thrice a week, for 4 weeks. Results: After therapy, improvement was seen in swallowing classification by Dysphagia Outcome and Severity Scale (P = .023) and a significant difference in the sum of points of SWAL-QOL questionnaire (P = .008) between periods, before, and after 3 months of therapy with NMES. No differences were found between rehabilitation periods, as to waste in the pharynx and times of oral and pharyngeal transit (P > .005). Conclusions: The application of NMES, at the sensory level, in elderly patients affected by stroke resulted in decreased dysphagia and in improved quality of life related to swallowing.

Effectiveness of Different Application Parameters of Neuromuscular Electrical Stimulation for the Treatment of Dysphagia after a Stroke: A Systematic Review

“…A total of 21 articles were found, of which eleven were focused on experimental researchs [ 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 ] and nine were randomized-controlled trials [ 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 ]. The methodological characteristics of the analysed studies are shown in Table 2 and, in Table 3 , the characteristics of the interventions applied in them are presented.…”

“…The application of NMES was not conducted using the same parameters in the analysed investigations. Regarding the application frequency, the choice of 80 Hz was the most widely used [ 27 , 28 , 29 , 30 , 31 , 32 , 33 , 35 , 36 , 37 , 39 , 40 , 41 , 42 , 45 ], although, in several cases, this parameter was not mentioned [ 34 , 38 , 44 , 46 ] and in another two studies the authors selected lower frequencies (60 [ 47 ] and 30 Hz [ 43 ]). In all cases, the results were statistically significant; even those studies which used lower frequencies obtained significant reductions in oral and pharyngeal transit time [ 47 ], significant decreases in the severity of penetration and aspiration [ 43 ] and significant increases in the level of oral intake and quality of life [ 43 ].…”

“…The impulse time was also a parameter that varied depending on the study analysed. The most frequent duration was 700 μs [ 28 , 29 , 30 , 32 , 33 , 35 ], although there were studies that used shorter (300 μs [ 31 , 40 , 41 ]) and longer durations (300 [ 27 , 36 , 37 ], 700 [ 39 ] and 800 [ 44 ] ms). In all the analysed cases, the results were significantly positive; even the studies that used shorter impulse times detected improvements in the quality of sleep, level of oral intake, presence and severity of penetration and aspiration, and capacity to communicate and swallow (higher elevation of the pharynx, closing of the epiglottis and coaptation of the pharyngeal wall), although more notably in those cases in which NMES was combined with Mendelsohn maneuvers (and other conventional DP treatment techniques) compared to its use as a single treatment technique [ 31 , 40 , 41 ].…”

“…The electrodes were preferentially placed in the anterior side of the neck: suprahyoid [ 27 , 31 , 32 , 33 , 36 , 37 , 38 , 39 , 42 , 43 , 44 , 45 , 46 , 47 ] or infrahyoid area [ 35 ], thyroid muscles [ 28 , 41 , 44 ], and lateral regions of the pharynx [ 40 ], although some authors also applied NMES in the cranium: in the paretic facial area [ 29 ], orbicularis orbis muscle [ 30 ] and masseters [ 37 ]. Two of the analysed articles were focused on comparing the effects of different application areas.…”

“…The duration of the treatment sessions ranged between 20 [ 27 , 33 , 37 , 44 , 47 ] and 60 min [ 34 , 38 , 46 ], although the most frequent duration was 30 min [ 28 , 29 , 30 , 31 , 32 , 35 , 36 , 41 , 42 , 43 ]. In all cases, the results were significantly positive; however, it is important to highlight that those interventions with longer sessions did not obtain improvements in pharyngeal closure [ 47 ] or in the Brunnstrom’s motor stages [ 43 ] and, although the analysed patients did improve in the intensity of perceived pain, level of oral intake, swallowing, aspiration and penetration events and oral and pharyngeal transit times, such improvements were greater in the groups of patients who received traditional DP therapy [ 47 ] or McNeill’s therapy [ 46 ] with respect to those who received NMES.…”