Table 1

Ventilatory management protocol

Volume controlledTime cycled, pressure limited
Initial modePTV (Assist/Control)PTV (Assist/Control)
Tidal volumeAdjust volume to deliver 5–8 mL/kgAdjust PIP to deliver 5–8 mL/kg
Time limitUse flow to adjust inspiratory time of 0.3–0.5 secInspiratory time 0.3–0.5 sec, use expiratory trigger to achieve full synchronisation
Maintain target ABGpH 7.27–7.40pH 7.27–7.40
PCO2 4.5–6 KPAPCO2 4.5–6 KPA
PO28–11KPAPO2 8–11 KPA
WeaningWean by reducing rate but continue to deliver tidal volume of 5–8 mls/kg. When rate ⩽40 bpm, switch to SIMV with PSV (minimum 10–12 cm H2O)Wean by reducing PIP as tolerated but continue in PTV with control rate of 20–40 bpm and tidal volume delivery at 5–8 mls/kg.
“Success” criteria outcomeA-aDO2 <13 kpa1-150 >12 hA-aDO2 <13 kpa >12 h
MAP<8.0 cm HsO >12 hMAP <8.0 cm H2O >12 h
Extubation (>12 hrs) before predetermined end pointsExtubation (>12 hrs) before predetermined end points
  • 1-150 100 torr (1 KPA=7.5 torr). PTV=patient triggered ventilation; SIMV=synchronised intermittent mandatory ventilation; PSV=pressure support ventilation; ABG=arterial blood gas; MAP=mean artery pressure; PIP=pulmonary inspiratory pressure.