Overview
This clinical study aims to compare the effects of conventional physical therapy alone versus conventional physical therapy combined with neuromuscular electrical stimulation (NMES) in patients admitted to the ICU and undergoing invasive mechanical ventilation. Participants will be randomly assigned to receive either conventional physical therapy or the same therapy plus NMES applied to the lower limbs. The protocol includes muscle-specific stimulation parameters and safety criteria to postpone sessions in cases of clinical instability. The primary goal is to assess whether NMES improves muscle function and recovery in critically ill patients.
Description
This randomized clinical trial will investigate the effects of neuromuscular electrical stimulation (NMES) in critically ill patients undergoing invasive mechanical ventilation. Participants will be randomly assigned to two groups: a control group receiving conventional physical therapy alone and an intervention group receiving conventional physical therapy combined with NMES.
The control group will receive individualized conventional physical therapy, adjusted daily based on each patient's physiological status and following protocols supported by current literature. Interventions may include progressive mobility, such as bed exercises, rolling, sitting at the edge of the bed, standing, chair transfers, and ambulation, as well as respiratory physiotherapy techniques including bronchial hygiene, pulmonary re-expansion, and management of mechanical ventilation. Sessions will last approximately 20 minutes and continue throughout hospitalization, except in cases of clinical contraindications or refusal by the patient/family.
The NMES group will receive the same conventional physical therapy described above, plus NMES applied once or twice daily to both lower limbs for up to 20 consecutive days or until hospital discharge, whichever comes first.
Rectangular electrodes (90 × 50 mm) will be placed bilaterally on the vastus lateralis, vastus medialis, tibialis anterior, hamstrings, and gastrocnemius muscles. If hair interferes with electrode adhesion, the area will be shaved.
NMES will be delivered using the ReCARE® device (Visuri, MG, Brazil) with the following parameters:
Frequency: 60 Hz
Pulse duration: 500 µs
Intensity: adjusted to produce visible muscle contractions during the first two days and, from day three onward, contractions sufficient to generate movement against gravity.
Contraction (on) and relaxation (off) times and the number of contractions will be progressively adjusted according to the 20-day protocol:
Days 1-2: On = 9s, Off = 27s, 16 contractions, 2x/day
Days 3-6: On = 9s, Off = 25s, 26 contractions, 2x/day
Days 6-9: On = 9s, Off = 22s, 60 contractions, 1x/day
Days 10-15: On = 9s, Off = 20s, 70 contractions, 1x/day
Days 16-20: On = 12s, Off = 15s, 70 contractions, 1x/day
NMES sessions will be postponed if the participant exhibits any of the following clinical findings within three hours prior to the session:
Acidosis (arterial pH < 7.25 or venous pH < 7.20)
Hypotension or hypertension (mean arterial pressure < 60 mmHg or > 140 mmHg)
Use of a single vasopressor at >50% of the ICU maximum dose (e.g., dopamine >12.5 µg/kg/min, phenylephrine >2 µg/kg/min, vasopressin ≥0.02 U/min, norepinephrine >1 µg/kg/min)
Use of two vasopressors at ≥40% of the ICU maximum dose
New diagnosis of pulmonary embolism or deep vein thrombosis without anticoagulation for more than 48 hours
Other signs of physiological instability, including temperature <34°C or >41°C, lactate >3.0 mmol/L, creatine kinase >400 U/L, platelet count <20,000/mm³, or suspected muscle inflammation (e.g., rhabdomyolysis, myositis, neuroleptic malignant syndrome, or serotonin syndrome).
This study aims to determine whether NMES, as an early adjunct therapy, can improve recovery and clinical outcomes in critically ill mechanically ventilated patients when combined with conventional physical therapy.
Eligibility
Inclusion Criteria:
- Patients will be eligible if they are 18 years or older, are under invasive mechanical ventilation (IMV), and are expected to require IMV for more than 48 hours.
Exclusion Criteria:
- Body mass index (BMI) greater than or equal to 35 kg/m²;
- Length of ICU stay longer than 7 ICU-free days or more than 3 continuous days of invasive mechanical ventilation (IMV) before enrollment;
- Known intracranial process (e.g., stroke, intracranial hypertension);
- Neuromuscular disease (e.g., Guillain-Barré syndrome, myasthenia gravis) at ICU admission;
- Inability to speak Portuguese or pre-existing cognitive impairment prior to ICU admission;
- Any condition that prevents neuromuscular electrical stimulation (NMES) treatment or assessment of the primary outcome in both legs (e.g., skin lesions, fractures, or amputation);
- Inability to transfer independently from bed to chair before ICU admission;
- Cardiac arrest as the cause of ICU admission or cardiac arrest before screening;
- Deep vein thrombosis (DVT) or pulmonary embolism (PE) treated for less than 48 hours;
- Pregnant patients;
- Known or suspected malignancy in the legs;
- Any care limitation including a do-not-resuscitate order.