Prevention of muscle atrophy in ICU patients without nerve injury by neuromuscular electrical stimulation: a randomized controlled study

Abstract

Background: Extensive muscle atrophy is a common occurrence in orthopaedics patients who are bedridden or immobilized. The incidence is higher in intensive care unit (ICU) inpatients. There is still controversy about how to use neuromuscular electrical stimulation (NMES) in ICU patients. We aim to compare the effectiveness and safety of NMES to prevent muscle atrophy in intensive care unit (ICU) patients without nerve injury.

Methods: ICU patients without central and peripheral nerve injury were randomized into experimental group I (Exp I: active and passive activity training (APAT) + NMES treatment on the gastrocnemius and tibialis anterior muscle), experimental group II (Exp II: APAT + NMES treatment on gastrocnemius alone), and control group (Ctl: APAT alone). Changes in the strength of gastrocnemius, the ankle range of motion, and the muscle cross-section area of the lower leg were evaluated before and after the intervention. Also, changes in prothrombin time, lactic acid, and C-reactive protein were monitored during the treatment.

Results: The gastrocnemius muscle strength, ankle joint range of motion, and cross-sectional muscle area of the lower leg in the three groups showed a downward trend, indicating that the overall trend of muscle atrophy in ICU patients was irreversible. The decrease in gastrocnemius muscle strength in Exp I and Exp II was smaller than that in the control group (P < 0.05), but there was no difference between Exp I and Exp II. The decrease in active ankle range of motion and cross-sectional area of the lower leg Exp I and Exp II was smaller than that in the control group (P < 0.05), and the decrease in Exp I was smaller than that of Exp II (all P < 0.05). The curative effect in Exp I was better than in Exp II. There were no significant differences in the dynamic changes of prothrombin time, lactic acid, and C-reactive protein during the three groups (P > 0.05).

Conclusion: In addition to early exercise training, NMES should be applied to prevent muscle atrophy for patients without nerve injury in ICU. Also, simultaneous NMES treatment on agonist/antagonist muscle can enhance the effect of preventing muscle atrophy.

Trial registration: This study was prospectively registered in China Clinical Trial Registry ( www.chictr.org.cn ) on 16/05/2020 as ChiCTR2000032950.

Keywords: Efficacy; ICU; Muscular atrophy; NMES; Prevention; Safety; Strategy.

Fig. 1

Flow diagram of the study

Fig. 2

Neuromuscular electrical stimulation treatment. a NMES on the gastrocnemius and tibialis anterior muscles in experimental group I . b NMES on gastrocnemius alone in experimental group II

Fig. 3

Measure the strength of gastrocnemius muscle (a) and Active joint range of motion of ankle joint (b)

Fig. 4

Lower leg CT plain scan and muscle area marking. a CT cross-section image of the lower leg (10 cm below the tibial tubercle). b Muscle boundary was marked with ImageJ; the cross-sectional area of the muscle was automatically calculated

Fig. 5

Comparison of gastrocnemius muscle strength before and after treatment. a Decrease of gastrocnemius muscle strength before and after treatment in the three groups. b Gastrocnemius muscle strength gap before and after treatment among the three groups. Exp I: experimental group I, Exp II: experimental group II, Ctl: control group; Bef: before treatment, Aft: after treatment; * P < 0.05 between each group before and after treatment; ^# P < 0.05 vs. control group

Fig. 6

Comparison of AROM of ankle joint before and after treatment. a AROM of ankle joint before and after treatment among three groups. b Comparison of ankle AROM gap before and after treatment in three groups. Exp I: experimental group I, Exp II: experimental group II, Ctl: control group; Bef: before treatment, Aft: after treatment; * P < 0.05 between each group before and after treatment; ^# P < 0.05 vs. control group; ^& P < 0.05 between the Exp I and the Exp II

Fig. 7

Comparison of muscle CSA of the lower leg before and after treatment. a Decrease of muscle CSA of the lower leg before and after treatment among three groups. b Comparison of muscle CSA gap before and after treatment in three groups. Exp I: experimental group I, Exp II: experimental group II, Ctl: control group; Bef: before treatment, Aft: after treatment; CSA: cross-sectional area; * P < 0.05 between each group before and after treatment; ^# P < 0.05 vs. Ctl; ^& P < 0.05 between Exp I and the Exp II

Fig. 8

Comparison of the changes of CRP (a), lactic acid (b), and PT (c) in the three groups during treatment. Exp I: experimental group I, Exp II: experimental group II, Ctl: control group