Background and purpose: We instituted a low-repetition, high-intensity inspiratory muscle strength training (IMST) program and progressively longer spontaneous breathing periods (SBPs) in a group of medically complex patients who were dependent on mechanical ventilation (MV) and had failed to wean.
Case descriptions: IMST was provided to 10 consecutive patients (four men, six women; mean [+/- SD] age, 59 +/- 15 years) who had failed to wean from MV by conventional methods for >or= 7 days. Prior to initiating IMST, patients had received MV support for a mean of 34 +/- 31 days. Daily IMST consisted of four sets of six breaths through a threshold inspiratory muscle trainer that had been set at an intensity to yield an exertion rating of 6 to 8 of a maximal value of 10. At the start of IMST, patients were tolerating 2.1 +/- 3.4 consecutive hours of SBPs. The duration of the SBPs was increased daily, as tolerated. Patients were considered to have been weaned from MV when they were able to breathe without MV support for 24 consecutive hours.
Outcomes: After 44 +/- 43 days of IMST, 9 of 10 patients were weaned from MV. The initial IMST pressure was 7 +/- 3 cm H(2)O, and it was increased to 18 +/- 7 cm H(2)O (p < 0.05).
Discussion: These results indicate that an IMST protocol that produces significant increases in threshold training pressure, in combination with progressive SBPs, aids in weaning patients from MV. Although promising, these preliminary observations must be tested in a controlled trial.