INTRODUCTION:

Dysphagia is the perception that there is an impediment to the normal passage of swallowed material which can manifest as a difficulty in the initial phases of a swallow which is usually described as “oropharyngeal dysphagia” whereas, the sensation that food or liquids are somehow being obstructed in the passage from mouth to stomach is described as esophageal dysphagia.¹ Normal control of swallowing requires appropriate function of the brain stem, the basal ganglia, the thalamus, the limbic system, the cerebellum, the motor and sensory cortices.

These systems control afferent and efferent, anticipatory and preparatory, voluntary and automatic processes. Over 30 muscles are involved in swallowing and are coordinated by a complex neural network that is not completely understood.² Literature shows that more than 50 % of stroke survivors are affected from dysphagia³. Mortality rate for dysphagic stroke patients being 27% and 37%.⁴ This Mortality rate was more than 30 % in stroke survivors with Dysphagia compared to stroke subjects without dysphagia. Dysphagic stroke patients recover swallowing function within 7 days and approximately 11–13 % remain dysphagic even after 6 months.^5,6 In 80 % of patients with prolonged dysphagia there is a requirement of alternative means of enteral feeding as per the studies conducted.⁷It is proved that Dysphagia is an independent predictor for respiratory morbidity and mortality in stroke.⁸ Neuromuscular electrical stimulation (NMES), which induces the functional recovery of swallowing using electrical stimulation on paralyzed muscles, is frequently used in swallowing treatment. Being a non-invasive treatment, NMES has the advantage of being easier to apply than traditional treatment techniques such as compensatory approach and can be effectively used for patients with damaged cognitive function for whom compensatory treatment is difficult to apply.⁹ When electrical stimulation is applied to the skin or oral mucosa at low current levels, it activates the sensory nerve endings in the surface layers providing sensory feedback to the central nervous system. With increased current amplitude, the electric field may depolarize nerve endings in muscles lying beneath the skin surface¹⁰and may spread with diminishing density to produce muscle contraction.

Swallowing difficulties can be a symptom of many different disease processes, and are associated with adverse health outcomes; malnutrition, dehydration, pneumonia and death. The use of feeding tubes directly into the stomach as in these patients with more and more being care taken by the family members. Living with a gastrostomy tube brings physical and emotional impacts and direct consequences for quality of life. Impaired swallowing can cause increased anxiety and fear. Many patients avoid oral intake leading to malnutrition, isolation and depression and this a complex and challenging area of health care.¹¹

METHODOLOGY:

Subjects who are willing to participate in this study were screened for Inclusion and Exclusion criteria. They were explained about the safety and simplicity of the procedure and informed consent were obtained. A total 30 Post stroke Patients were screened for Functional oral Intake Scale, and Quality of Life Questionnaire as a pre test measurement. All 30 Patients received Pharyngeal Electrical stimulation. For that Patient position was supine lying Pillow supported under the head of the subject. Electrode Placement- Inactive electrode placed under the Neck region, Active electrode over the pharyngeal area of either side of the Hyoid Bone. Electrical stimulation was given with the frequency of 30 Hz, duration of 100ms, intensity was increased till minimal palpable observable contraction interrupted direct current is used. This treatment technique was followed 2 weeks duration for single session per day for 6 days/ week. End of the second week Post test Measurement was taken Functional Oral Intake scale and quality of life questionnaire. And values were tabulated statistically analysed.

RESULTS:

Results from this study in post stroke dysphagic patient’s Functional oral intake scale pre test measurement values were 1.87 and Standard deviation 0.82 and post test measurement mean-4.83, standard deviation -1.05, between pre and post test t value-15.24, p value was P value 0.0001.(Table 1), Quality of life pre test measurement mean 62.77 standard deviation 4.95 and post test measurement mean 47.27 and standard deviation 7.35 between pre and post measurement t value -11.30 and P value 0.0001.(Table 2)

DISCUSSION:

Swallowing tends to occur during the expiration phase of respiration. Expiration occurs after 80–100 percent of healthy swallows. This is likely to be a protective mechanism: material left in the laryngeal vestibule post swallow was moved to the pharynx rather than sucked into the lungs. Post-swallow inspiration is more common in populations with impaired swallowing. There does not seem to be an effect of bolus volume or gender on the exhale–swallow–exhale pattern.

Our purpose was to determine the swallowing function and quality of life in subjects with post stroke dysphagia. The major effect of stimulation at rest was to pull the Hyo-laryngeal complex downwards using each of the combined electrode placements and all of the inferior placements. Philip M. Bath et al in his study in healthy volunteers suggested that PES should be delivered at 5 Hz for 10 minutes with an electric current of threshold plus 75% of the difference between threshold and tolerance levels, a paradigm that produced the largest effect on brain excitability.¹² In this study the Inactive electrode placed under the Neck region, Active electrode over the pharyngeal area of either side of the Hyoid Bone. Electrical stimulation was given with the frequency of 30 Hz, duration of 100ms, intensity was increased till minimal palpable observable contraction and interrupted direct current was used. This treatment technique was followed 2 weeks duration for single session per day for 6 days/ week by using this approach in patients with post-stroke dysphagia, the ability of swallowing and quality of life was being significantly improved which was documented by using two outcome measures i.e., functional oral intake scale and quality of life.

Lee KW in his study concluded that application of NMES showed a positive effect in acute/sub acute ischemic stroke patients with dysphagia. In their results indicated that the early application of NMES could be used as a supplementary treatment to help rehabilitate acute/sub acute dysphagic stroke patients by improving their swallowing coordination¹³. Similarly in our study the results which was obtained after the Pre and Post test using functional oral intake scale and quality of life questionnaire was found to be statically significant which emphasis the use of electrical stimulation in post stroke dysphigia has a good effects in swallowing as well as in improving quality of life.

Pharyngeal stimulation improving the swallowing during the pharyngeal phase which includes the bolus to moved back by the tongue to enter the pharynx and a sequence of events is initiated that ensures that the airways are protected during bolus transport Firstly, diaphragmatic contraction is inhibited making simultaneous breathing and swallowing impossible under normal circumstances. At the same time, the soft palate is elevated to ensure a sphincter closure of the nasopharynx. Finally, the vocal cords start to close to protect the airways where the ‘trigger point’ may be the ‘summation of afferent signals for the entire oropharyngeal sensory field where the bolus enters the oropharynx touches key trigger points a reflex is initiated in which the constrictors relax to dilate the pharynx The pharynx and larynx are raised by the longitudinal muscles The bolus is propelled over the epiglottis by the action of the constrictors contracting in sequence. The larynx is then closed by contraction of the muscles of the laryngeal inlet however this normal physiological function get impaired with the post stroke patient with dysphigia therefore can be activate by using Neuro muscular electrical stimulation.

CONCLUSION:

This study showed that Neuro Muscular Electrical stimulation is effective in improving swallowing function in and Quality of life in patients with Post stroke dysphagia

Table-1-Pre and Post test Values of FOIS on Post stroke dysphagic Patients

Post Stroke Dysphagic Patients		Mean	Standard Dev iation	t-value	p-value
FOIS	Pre	1.87	0.82	15.2402	0.0001
FOIS	Post	4.83	1.05	15.2402	0.0001

Table-2- Pre and Post test Values of Quality of life on Post stroke dysphagic Patients

Post Stroke Dysphagic Patients		Mean	Standard Dev iation	t-value	p-value
QOL	Pre	62.77	4.95	11.3049	0.0001
QOL	Post	47.27	7.35	11.3049	0.0001

Graph-1-Graphical Representation for Pre and Post test Values

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Received on 09.08.2018 Modified on 27.09.2018

Research J. Pharm. and Tech 2018; 11(12): 813-821.

DOI: 10.5958/0974-360X.2018.01011.9