Effects of neuromuscular electrical stimulation therapy on physical function in patients with COVID-19 associated pneumonia: Study protocol of a randomized controlled trial

Purpose: Neuromuscular electrical stimulation (NMES) has been considered as a promising approach for the early rehabilitation of patients during and/or after intensive care unit (ICU) stay. The overall objective of this study is to evaluate the NMES effectiveness to counteract the post-ICU impairment in physical function of COVID-19 patients. The specific aim of this manuscript is to describe the study design, protocol, content of interventions, primary and secondary outcomes and to discuss the clinical rehabilitation impact of the expected experimental results. Methods: This prospective, randomized, controlled, parallel-group, single-blind trial will include 80 patients who had undergone mechanical or non-invasive ventilation following pneumonia-induced respiratory failure. Patients are randomized to a control group (routine physical therapy for 3 weeks) or a NMES group (routine physical therapy plus NMES of quadriceps and gastrocnemius muscles for 3 weeks). The primary outcome is physical performance assessed through the Short Physical Performance Battery (SPPB). Secondary outcomes include independence level, perceived fatigue, muscle strength, rectus femoris thickness, and walking performance. The SPBB and walking performance are assessed once (after the intervention), while all other outcomes are assessed twice (before and after the intervention). Conclusion: NMES is a simple and non-invasive technique for muscle strengthening that is usually well tolerated, does not produce adverse effects, requires no or little cooperation from patients and is quite inexpensive. Therefore, proving the effectiveness of NMES therapy for physical and muscle function in COVID-19 patients could support its systematic incorporation in post-ICU rehabilitation protocols of patients presenting with post-intensive care syndrome.