A randomized controlled study of neuromuscular electrical stimulation in oropharyngeal dysphagia secondary to acquired brain injury.

Background and purpose To evaluate the effectiveness of neuromuscular electrical stimulation (NMES) treatment in patients with oropharyngeal dysphagia secondary to acquired brain injury. Methods Twenty patients with neurological oropharyngeal dysphagia (14 stroke and six severe traumatic brain injury) were enrolled in a prospective randomized study, with patients and assessors blinded (to group allocation): 10 patients underwent NMES and conventional swallowing therapy and 10 patients underwent sham electrical stimulation (SES) and conventional swallowing therapy. Both groups completed 20 sessions. At baseline, at the end of treatment (1 month) and at 3-month follow-up, clinical, videofluoroscopic and esophageal manometric analyses were done. Feeding swallowing capacity was evaluated using the functional oral intake scale (FOIS). Results Mean FOIS score before treatment was 1.9 for the NMES group and 2.1 for the SES group. After treatment, the NMES group increased by 2.6 points (4.5 points) compared with only 1 point (3.1 points) for the SES group (P = 0.005). At 3 months of follow-up, mean scores were 5.3 and 4.6 respectively; thus, both groups improved similarly. At that time point (3 months), tracheal aspiration persisted in six patients in each group. However, a significant improvement in relation to the bolus viscosity at which aspiration appeared was found in the NMES group versus the SES group (P = 0.015). Also, a significant increase (P = 0.04) in pharyngeal amplitude contraction was observed at the end of treatment (1 month) in the NMES group compared with the SES group. Conclusion Neuromuscular electrical stimulation significantly accelerated swallowing function improvement in patients with oropharyngeal dysphagia secondary to acquired brain injury.