Evaluation of modified Integrative Weaning Index to predict the weaning outcome in mechanically ventilated patients.

Weaning is the process of gradually withdrawing mechanical ventilatory support and transferring the work of breathing from the ventilator to the patient.

A weaning index or predictive parameter for weaning is a criterion that evaluates a given physiological aspect of respiratory function, with the objective of distinguishing between patients who might tolerate the SBT and those who might not.Spontaneous Breathing Trial (SBT) is a part of weaning process which evaluates the patient spontaneous efforts without any ventilatory support.Weaning Indexes are the parameters which are use to evaluate the patient’s rediness for extubation or liberation of ventilatory support.Weaning Indexes that evaluate one single function have generally presented poor accuracy in comparison with the integrative parameters.

Hence  having the Integrated weaning Index or Integrative parameters that evaluate more than one physiological aspect of respiratory function may predict the SBT tolerance  (weaning success) or SBT intoerance (weaning failure).One such integrative weaning index has introduced and stated as IWI = (Cst,rs × SaO2) ÷ RR/V T  and concluded that IWI is the best predictive performance index of weaning outcome.However the study has limitation that calculating Static compliance during the weaning phase by taking the patient back on Volume control mode. Hence we presented the Modified Integrative Weaning Index by substitute Static compliance with Dynamic compliance and stated as Modified IWI=(Cdyn,rs × SaO2) ÷ RR/V T.