Introduction: The Mechanical Ventilation (MV), a support method used in Intensive Care Units (ICU), reaches approximately 90% of critical patients whose withdrawal process represents 40% of the total time of their use. For this purpose Transcutaneous electrical diaphragmatic stimulation (TEDS), which by means of electrodes placed in motor action points on the phrenic nerve tend to provide improvement of the diaphragm muscle function. Objective: To analyze the effect of two protocols of transcutaneous electrical diaphragmatic stimulation on the ventilatory and cardiorespiratory parameters of critically ill patients. Method: Clinical, longitudinal, prospective, quantitative, single center trial will be performed with 30 (thirty) participants in invasive mechanical ventilatory support, randomly divided into three groups: Experimental Group 1 (GE-1; n = 10) where they will be submitted to the TEDS protocol; Experimental Group 2 (GE-2; n = 10), where they will be submitted to the TEDS protocol based on the studies of Cancelliero et al. (2012); Control Group (GC; n = 10) where they will not be submitted to TEDS. All groups will receive physiotherapeutic care from the staff of the adult ICU of the FHCGV. The interventions will consist of ten sessions of Physical Therapy in each participant in the afternoon shift, for ten consecutive days, 1 time a day. For the TEDS procedure, the Orion TENS II (Orion-SP-Brazil) model will be used, the Wright analogue respirometer (Spire-SP-Brazil) will be used for the minute volume evaluation (V'). The variables of systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and peripheral oxygen saturation (SpO2) will also be monitored in order to verify if the TEDS application interferes with the hemodynamic variables of these patients. The data collected will be linked to Microsoft Office Excel® 2010 software and later transformed into tables and graphs. The information collected will be submitted to statistical analysis through the statistical package SPSS 22.0, applying the descriptive statistics for the characterization of the sample and then selecting the specific tests for the respective variances, adopting a level of significance of p≤0.05 for statistical inferences.

Inclusion Criteria:

• Individuals of both sexes aged 60 years and older up to 80 years,
• in invasive MV for more than 48 hours,
• with respiratory drive,
• using MV in the mode of intermittent mandatory synchronized ventilation (VMIS) or (VPS),
• connected to the orotracheal tube or via tracheostomy,
• hemodynamically stable,
• neuromuscular junction of the entire diaphragm,
• absence of sedatives.

Exclusion Criteria:

• presence of pacemaker, hyperthermia (temperature> 38 ° C),
• use of neuromuscular blockers,
• use of thoracic drains, generalized edema,
• cutaneous lesion in the area of intervention with TEDS.

Individuals aged 60 years and older up to 80 years