Use of a New Isokinetic Device for Inspiratory Muscle Training
Condition: Respiration, Artificial
MeSH terms: Respiratory Aspiration
Study type: Interventional

Summary: 
      Introduction:

      It is well established that physical fitness improves muscle performance either in sedentary
      people or in athletes. In this regard, specific exercises for respiratory muscles can result
      in better functional performance in hospitalized individuals, especially in critically ill
      patients in prolonged weaning.

      Objectives:

      To compare the following variables between intervention and control patients: success in
      weaning, free time off ventilator on ICU after weaning, and gain of muscle strength with the
      use of the inspiratory muscle training (IMT).

      Patients and methods:

      Prospective randomized controlled clinical trial. Only individuals on prolonged weaning will
      be enrolled. They will undergo IMT or will be managed in a conventional manner. The primary
      endpoint will be successful weaning. In addition, other variables such as free time off
      ventilator on ICU after weaning and muscle strength will be measured. In addition, mortality
      in the ICU, inside the hospital and after discharge will be followed for one year after study
      entrance.

      Expected results:

      According to the working hypothesis, it is expected that the performance of patients
      undergoing IMT will be superior to the conventional treatment. Also, their time to mortality
      is expected to be longer.
    

Detailed description: 
      The control group only performed inspiratory muscle training (IMT) with the use of the
      T-piece. From the first day of prolonged weaning, patients would remain in spontaneous
      breathing progressing their stay time each day, respecting the criteria already mentioned for
      interruption and return to mechanical ventilation in support pressure mode.

      The intervention group, in addition to the protocol described above, would undergo
      inspiratory muscle training with the POWER breathe K-5 (UK) device. POWER breathe K-5 will be
      employed once a day, with an initial loading of 40% of maximal inspiratory strength in a
      schedule of 30 repetitions. This number of repetitions could be reached in one to 6 sessions
      depending on the respiratory muscle force of the patient. Most of the times more than one
      session were required. Typically, subjects performed two to six sessions of 5 to 15 breaths
      per day, with two minutes rest in ventilation pressure support mode. When the patient was
      unable to comply with the schedule, the training session was interrupted at a total of 3
      minutes. The load was planned to be adjusted weekly with a 5 to 10% increase until 60% of the
      maximal inspiratory strength was reached with a total time of 10 minutes or 100 breaths.
      After training with POWER breathe K-5 (UK), the patient would return to mechanical
      ventilation in support pressure mode for 30-60 minutes, and then follow the conventional
      T-piece protocol. The IMT was conducted normally between 08h and 10h, Monday through Friday.

      All study subjects would be under continuous surveillance through the multi-parameter DX 2010
      monitor (Dixtal, São Paulo, SP, Brazil), which records the electrocardiogram, heart rate,
      peripheral oxygen saturation and systemic arterial pressure. At any sign of instability, the
      IMT was interrupted and the patient returned to the ventilatory support and/or supplemental
      oxygen therapy for recovery.

      The trial was stopped if at least one of the following intolerance criteria was present:
      SaO2<90% or PaO2 <60 mm Hg with FIO2 >0.4; PaCO2 > 50 mm Hg or increased by > 8 mm Hg;
      arterial pH < 7.33 or decreased by 0.07 or more; breathing frequency > 35 breaths/min or
      increased by 50% for 5 min or longer; heart rate > 140 beats/min or a sustained increase or
      decrease of > 20%; mean blood pressure > 130 or < 70 mm Hg; or presence of agitation,
      diaphoresis, disorientation, or depressed mental status.
    

Intervention name(s): Inspiratory muscle training
Intervention type(s): Device
Intervention description(s): For the inspiratory muscle training, an isokinetic device (K5 Power Breath, United Kingdom) will be attached to the artificial airway.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Supportive Care
Keywords: Mechanical Ventilator Weaning; Respiratory Muscle Training; Mortality Rate