Early neuromuscular electrical stimulation reduces the loss of muscle mass in critically ill patients ? A within subject randomized controlled trial

Purpose: To investigate the effect of Neuromuscular Electrical Stimulation (NMES) on muscle thickness, strength and morphological and molecular markers of the quadriceps. Materials and methods: Adult critically ill patients with an expected prolonged stay received unilateral quadriceps NMES sessions for 7 consecutive days. Before and after the intervention period, quadriceps thickness was measured with ultrasound. After the intervention period, strength was assessed in cooperative patients and muscle biopsies were taken. Multivariable regression was performed to identify factors affecting muscle thickness loss. Results: Muscle thickness decreased less in the stimulated leg (& minus;6 +/- 16% versus & minus;12 +/- 15%, p = 0.014, n = 47). Strength was comparable. Opioid administration, minimal muscle contraction and more muscle thickness loss in the non-stimulated muscle were independently associated with better muscle thickness preservation. Stimulated muscles showed a shift towards larger myofibers and higher MyHC-I gene expression. NMES did not affect gene expression of other myofibrillary proteins, MuRF-1 or atrogin-1. Signs of myofiber necrosis and inflamma-tion were comparable for both muscles. Conclusions: NMES attenuated the loss of muscle mass, but not of strength, in critically ill patients. Preservation of muscle mass was more likely in patients receiving opioids, patients with a minimal muscle contraction during NMES and patients more prone to lose muscle mass. Trial registration: clinicaltrials.gov NCT02133300 (c) 2020 Elsevier Inc. All rights reserved.

Automated summary

Neuromuscular Electrical Stimulation (NMES) attenuated muscle mass loss but did not improve strength in critically ill patients. Patients receiving opioids, experiencing minimal muscle contraction during NMES, and being more prone to muscle mass loss were more likely to preserve muscle mass.