Safety and Efficacy of Electrical Stimulation for Lower-extremity Muscle Weakness in Intensive Care Unit 2019 Novel Coronavirus Patients: A Phase I Double-blinded Randomized Controlled Trial

Background: Intensive care unit (ICU) prolonged immobilization may lead to lower-extremity muscle deconditioning among critically ill patients, particularly more accentuated in those with 2019 Novel Coronavirus (COVID-19) infection. Electrical stimulation (E-Stim) is known to improve musculoskeletal outcomes. This phase I double-blinded randomized controlled trial examined the safety and efficacy of lower-extremity E-Stim to prevent muscle deconditioning.

Methods: Critically ill COVID-19 patients admitted to the ICU were randomly assigned to control (CG) or intervention (IG) groups. Both groups received daily E-Stim (1 h) for up to 14 days on both gastrocnemius muscles (GNMs). The device was functional in the IG and non-functional in the CG. Primary outcomes included ankle strength (Ankle) measured by an ankle-dynamometer, and GNM endurance (GNM) in response to E-Stim assessed with surface electromyography (sEMG). Outcomes were measured at baseline, 3 and 9 days.

Results: Thirty-two (IG = 16, CG = 16) lower extremities in 16 patients were independently assessed. The mean time between ICU admission and E-Stim therapy delivery was 1.8 ± 1.9 days ( = 0.29). At 3 days, the IG showed an improvement compared to the CG with medium effect sizes for Ankle ( = 0.06, Cohen's = 0.77) and GNM ( = 0.06, = 0.69). At 9 days, the IG GNM was significantly higher than the CG ( = 0.04, = 0.97) with a 6.3% improvement from baseline ( = 0.029). E-Stim did not alter vital signs (i.e., heart/respiratory rate, blood saturation of oxygen), showed no adverse events (i.e., pain, skin damage, discomfort), nor interfere with ICU standard of care procedures (i.e., mechanical ventilation, prone rotation).

Conclusion: This study supports the safety and efficacy of early E-Stim therapy to potentially prevent deterioration of lower-extremity muscle conditions in critically ill COVID-19 patients recently admitted to the ICU. If confirmed in a larger sample, E-Stim may be used as a practical adjunctive therapy.

Clinical Trial Registration: [https://clinicaltrials.gov/], identifier [NCT04685213].