Inspiratory Muscle Training in Weaning
Condition: Weaning
MeSH terms: Respiratory Aspiration
Study type: Interventional
Phase: Phase 4

Summary: 
      Background: the objective of the present inquiry was to evaluate the weaning process in
      intubated older people subjected to inspiratory muscle training and to correlate the
      predictors of ventilatory interruption with its success.

      Methods: the patients were divided randomly into an experimental group (EG, n=14; age=82±4
      years) that received conventional physiotherapy plus inspiratory muscle training (IMT) with
      threshold IMT® and a control group (CG, n=14; age=81±6 years) that received only conventional
      physiotherapy. The predictors evaluates were the maximum inspiratory pressure (MIP) and the
      index of Tobin (IT). The protocol for muscle training consisted of an initial load of 30%
      MIP, which was increased by 10% daily; training was administered for five minutes, twice a
      day, seven times a week with supplemental oxygen for the entire period from the decision to
      wean up to extubation.
    

Detailed description: 
      The sample for this investigation was selected in a randomized way in the period between
      December 2007 and November 2008. The individuals were successively entered in the research as
      they were admitted to the ICU, in respect of the criteria of inclusion and exclusion. From
      the total number of admitted patients in the period (n=67), many were excluded because they
      had been tracheostomized (n=25), were dead (n=13) or were transferred out of the hospital
      (n=1). Those that remained intubated (n=28) and went to the spontaneous mode were chosen
      randomly and in alternating fashion were divided into the experimental group (EG) or the
      control group (CG). The EG (n=14; age=82±4 years-old) underwent conventional physiotherapy
      plus inspiratory muscular training with threshold IMT® (Respironics/EUA - 2004), and the CG
      (n=14; age=81±6 years-old) received only conventional physiotherapy with no intervention that
      favored the inspiratory muscle strengthening.

      As inclusion criteria, the individuals of the sample were required to have undergone MV for
      at least 48 hours in a controlled way13, as intubation is diagnostic for acute respiratory
      injury type 1 and has a maximum value of MIP of -20 cmH2O16.

      Exclusion criteria included any type of acute condition (cardiac arrhythmia) or chronic
      condition, such as insufficient congestive heart failure or unstable ischemic cardiac
      disease17, that could compromise weaning or could impede the accomplishment of inspiratory
      muscle training (neuropathy and myopathy). Tracheostomized patients (in the pre-test), those
      with neurological problems (cerebral vascular accident, cerebrospinal trauma or spinal
      medullar trauma), those with morbid obesity or those taking medicine that could cause a
      disorder of attention, as well as cases of auto-extubation, were also excluded.

      The criteria of inclusion and exclusion were evaluated via examination of the patients'
      medical records and physical examination daily and in each session. The daily adherence of
      the patients to the necessary parameters for the study was noted for each patient.
    

Intervention name(s): inspiratory muscle training
Intervention type(s): Other
Intervention description(s): Protocol of inspiratory muscle training using threshold IMT®: After the MIP was measured, inspiratory muscle training was initiated. The Threshold-IMT® device of a linear pressure load produces a resistance to inspiration through the use of a flow-independent one-way valve. During expiration there is no resistance because the unidirectional valve opens, while during inspiration the valve closes, becoming "hard" due to the resistance of the spring. The suggested protocol was: initial load of 30% of the M24, increasing daily by 10%, with training for five minutes, twice a day, seven times a week in the period from the beginning of the weaning from the MV until the extubation of the patient.
An essential factor was the use of supplemental oxygen (O2) as needed by the patient. The patients were in DD with fowler 45º.
Allocation: Randomized
Intervention model: Parallel Assignment
Keywords: weaning; inspiratory muscle training; maximum inspiratory pressure (MIP); index of Tobin (IT); intubated; intensive care unit; elderly