Neuromuscular Electrical Stimulation (NMES) Preserves Muscle Mass in Intensive Care Unit (ICU)
Condition: Critical Illness; Physical Disability; Muscle Atrophy
MeSH terms: Muscular Atrophy; Atrophy; Critical Illness
Study type: Interventional

Summary: 
      Background: Low-frequency neuromuscular electrical stimulation (NMES) attenuates the loss of
      muscle mass of Intensive Care Unit (ICU) patients. However, it has been shown that
      medium-frequency NMES may be better than low-frequency for the maintenance of skeletal muscle
      mass in healthy subjects.

      Objective: to compare the effects of low-frequency and medium-frequency NMES, along with a
      standard physical therapy (SPT) programme, on the attenuation of skeletal muscle atrophy in
      critically ill patients.

      Methods: Fifty-four critically ill patients admitted into intensive care unit (ICU) and on
      mechanical ventilation (MV) participated in this randomized, single-blinded, experimental
      study. Participants were allocated to one of the following groups: Control Group (CG),
      received a standard lower limb physical therapy (SPT) programme, 2x/day; Low-frequency NMES
      Group (LFG), received lower limb SPT+NMES at 100 Hz, 2x/day; and Medium-frequency NMES Group
      (MFG), received lower limb SPT+NMES at 100 Hz and carrier frequency of 2500 Hz, 2x/day. The
      primary outcome was the thickness and quality of the quadriceps muscle, evaluated with
      ultrasonography while patients were in ICU. Secondary outcomes, assessed at various stages of
      recovery, were strength, functionality, independence for activities of daily living, quality
      of life, and total days hospitalized.
    

Detailed description: 
      Background: Low-frequency neuromuscular electrical stimulation (NMES) attenuates the loss of
      muscle mass of Intensive Care Unit (ICU) patients. However, it has been shown that
      medium-frequency NMES may be better than low-frequency for the maintenance of skeletal muscle
      mass in healthy subjects.

      Research question: The research question was is medium-frequency neuromuscular electrical
      stimulation (NMES) more effective than low-frequency NMES for the attenuation of skeletal
      muscle atrophy in critically ill patients?

      Objective: To compare the effects of low-frequency and medium-frequency NMES, along with a
      standard physical therapy (SPT) programme, on the attenuation of skeletal muscle atrophy in
      critically ill patients.

      Methods: Fifty-four critically ill patients admitted into intensive care unit (ICU) and on
      mechanical ventilation (MV) participated in this randomized, single-blinded, experimental
      study. Participants were allocated to one of the following groups: Control Group (CG),
      received a standard lower limb physical therapy (SPT) programme, 2x/day; Low-frequency NMES
      Group (LFG), received lower limb SPT+NMES at 100 Hz, 2x/day; and Medium-frequency NMES Group
      (MFG), received lower limb SPT+NMES at 100 Hz and carrier frequency of 2500 Hz, 2x/day. The
      primary outcome was the thickness and quality of the quadriceps muscle, evaluated with
      ultrasonography while patients were in ICU. Secondary outcomes, assessed at various stages of
      recovery, were muscle strength (MRC-SS), handgrip strength (dynamometry), functional status
      (FSS-ICU), degree of independence for activities of daily living (Barthel Index), functional
      mobility and dynamic balance (Timed Up and Go Test), quality of life (SF-36), and total days
      hospitalized.
    

Intervention name(s): Patients received the standard physical therapy (SPT) programme (passive mobilization) twice a day.; Patients received the low-frequency neuromuscular electrical stimulation (NMES); Patients received the medium-frequency neuromuscular electrical stimulation (NMES)
Intervention type(s): Other; Other; Other
Intervention description(s): All participants have received standard physical therapy (SPT) sessions based on a passive range of motion mobilization protocol for the lower limbs. It consisted of a bilateral series of 10 repetitions of hip flexion, knee flexion and extension, and ankle flexion and extension. The procedure was performed twice a day: a morning (between 8am - 12pm) and an afternoon session (between 2pm - 6pm).; Electrical stimulation was performed twice a day after SPT. Two electrodes were attached to each thigh at the motor points of the quadriceps muscle. The point halfway between the anterior superior iliac spine and the base of the patella was used as reference and electrodes were placed 15 cm apart each other, 5 cm proximal and 10 cm distal from the reference point. After the first measurement, semi-permanent markers were used to indicate the position of electrodes. Electrical stimulation was performed using a 4-channels device (Sonopuls 492, series 4, Enraf-Nonius®, Rotterdam, Netherlands). The low-frequency protocol consisted of 100 Hz and 400 ms width pulses, delivered in trains of 5 s ON (ramp-up time: 1 s, plateau: 3 s, ramp-down time: 1 s) and 10 s OFF. Sessions had 20 min of duration (total of 40 min/day) and the current amplitude (mA) was adjusted to the identification of visible and palpable contractions and was rectified every 3 min to sustain the initial level of contraction.; Electrical stimulation was performed twice a day after SPT. Two electrodes were attached to each thigh at the motor points of the quadriceps muscle. The point halfway between the anterior superior iliac spine and the base of the patella was used as reference and electrodes were placed 15 cm apart each other, 5 cm proximal and 10 cm distal from the reference point. After the first measurement, semi-permanent markers were used to indicate the position of electrodes. Electrical stimulation was performed using a 4-channels device (Sonopuls 492, series 4, Enraf-Nonius®, Rotterdam, Netherlands).The medium-frequency protocol had similar parameters, but a carrier frequency of 2500 Hz and burst frequency of 100 Hz. Sessions had 20 min of duration (total of 40 min/day) and the current amplitude (mA) was adjusted to the identification of visible and palpable contractions and was rectified every 3 min to sustain the initial level of contraction.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: electrical stimulation therapy; skeletal muscle atrophy; critically ill patient; physical therapy; intensive care unit