00a95e53_The_Winning_Weaning_Parameters__3
[0] TI / TTOT Respiratory Time Fraction [1] .3-.4 [2] Increase of >.1* [3] 
Respiratory Time Fraction (TI / TTOT) indicates endurance and is defined as the ratio of the inspired time to the total time of the respiratory cycle. This value is a ratio and there is no unit of measure. As the respiratory muscles fatigue, the fraction of the breathing cycle spent in inspiration tends to increase. When there is respiratory muscle fatigue and impending respiratory failure the ratio between inspiratory time and total time available for the breath may incrementally increase to a point in which the respiratory pump can no longer maintain itself and the (TI / TTOT) may decrease dramatically. Excessive work of breathing is the common cause of elevated (TI / TTOT)
The Winning Weaning Parameters
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