<prompt> Shifting patient from assisted ventilation to voluntary ventilation which of the following shows failure?O2 saturation 80PEEP 5cmsRR 35 minsTidal volume 5 mlkg  <response>: Ans is a i.e. O2 saturation 80 O2 saturation of 90 is one of the criteria for successful weaning from mechanical ventilation.Numerical indices used to predict successful weaningIndicesValueMinute ventilation10L minuteVital capacitybody weight10ml kgRespiratory frequency35bpmTidal volume body weight5ml kgPEEP5cm H2ORespiratory rate tidal volume 100litreSpO290Heart rate 140bpm or change by 20Systolic BP180 or 90 mmHg 