Neuromuscular Electrical Stimulation (NMES) Preserves Muscle Mass in Intensive Care Unit (ICU)

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.

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.

Eligibility Criteria:
Inclusion Criteria:

- patients between 18-80 years old admitted in ICU with requirement of mechanical ventilation (MV) for longer than 72 h.

Exclusion Criteria:

* non-sedated patients;
* spinal cord injury;
* cerebrovascular accident;
* patients with pacemakers;
* history of deep vein thrombosis;
* pregnancy;
* cardiac complications (history of myocardial infarction or congenital diseases);
* use of neuromuscular blockers;
* polytraumatized patients requiring tutor support.