Coordination Between Respiration and Swallowing in Patients With Dysphagia After Cervical Spinal Cord Injury: An Observational Case-Control Study.

PURPOSE: The purpose of the present study was to characterize the differences between respiration and swallowing in patients with dysphagia after cervical spinal cord injury (CSCI) and to explore the underlying physiological changes. METHOD: A total of 95 participants were recruited for bedside swallowing evaluation followed by a flexible endoscopic evaluation of swallowing and surface electromyography with a thermocouple nasal airflow sensor examination: 32 with dysphagia, 33 without dysphagia, and 30 healthy controls. The differences in respiratory patterns, swallowing apnea duration (SAD), inspiratory-expiratory ratio, and swallowing efficiency were observed among healthy adults, CSCI patients with and without dysphagia after CSCI. RESULTS: Compared with those of healthy controls and patients without dysphagia after CSCI, the postswallow respiratory pattern of patients with dysphagia after CSCI was an inspiratory pattern, and the SAD was significantly shorter in patients with dysphagia after CSCI (p < .001). Additionally, the expiratory time in patients with dysphagia was significantly shorter than the inspiratory time, and the swallowing efficiency was reduced, requiring multiple swallows. Moreover, the index of SAD was statistically significant for predicting the development of dysphagia in patients with CSCI (p < .001). CONCLUSION: Patients with CSCI have an inspiratory pattern after swallowing, and the SAD is significantly reduced; SAD can be used as the predictor of dysphagia in patients after CSCI; the pattern of coordination between respiration and swallowing in patients with dysphagia after CSCI is different from that of healthy controls and patients without dysphagia after CSCI. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.26524717.

Glycine and N-Acetylcysteine (GlyNAC) Combined with Body Weight Support Treadmill Training Improved Spinal Cord and Skeletal Muscle Structure and Function in Rats with Spinal Cord Injury.

Skeletal muscle atrophy is a frequent complication after spinal cord injury (SCI) and can influence the recovery of motor function and metabolism in affected patients. Delaying skeletal muscle atrophy can promote functional recovery in SCI rats. In the present study, we investigated whether a combination of body weight support treadmill training (BWSTT) and glycine and N-acetylcysteine (GlyNAC) could exert neuroprotective effects, promote motor function recovery, and delay skeletal muscle atrophy in rats with SCI, and we assessed the therapeutic effects of the double intervention from both a structural and functional viewpoint. We found that, after SCI, rats given GlyNAC alone showed an improvement in Basso-Beattie-Bresnahan (BBB) scores, gait symmetry, and results in the open field test, indicative of improved motor function, while GlyNAC combined with BWSTT was more effective than either treatment alone at ameliorating voluntary motor function in injured rats. Meanwhile, the results of the skeletal muscle myofiber cross-sectional area (CSA), hindlimb grip strength, and acetylcholinesterase (AChE) immunostaining analysis demonstrated that GlyNAC improved the structure and function of the skeletal muscle in rats with SCI and delayed the atrophication of skeletal muscle.