CRITICAL CARE

More documents

Recommendations

Info

Central Sydney Health Service Royal Prince Alfred Hospital � Set respiratory rate to maintain the minute ventilation (MV) that was recorded prior to changing the ventilator settings (set f = old MV divided by new VT in litres). This may not be possible as the maximum set respiratory rate (f) is 35 � Ensure that Autoflow is turned on. � The airway pressure alarm must be set at 35 cm H2O. This will limit the maximal airway pressure to 30 cm H2O. � Turn the Flow Trigger “On” and set it to 2 L/min � Adjust the Inspiratory time to start with an I:E ratio of 1:3. I:E ratio is displayed in the bottom left corner of the “Ventilator settings” screen when Tinsp is selected. � Adjust the FiO2 and PEEP as outlined in the section arterial oxygenation goal (see below). SUBSEQUENT VENTILATOR ADJUSTMENTS TIDAL VOLUME AND INSPIRATORY TIME ADJUSTMENTS � These may be necessary if the alarm “pressure limited, volume not constant” occurs. This alarm indicates that the ventilator cannot deliver the programmed volume in the time allowed whilst keeping the pressure under the alarm limit of 35 cm H2O (actual airway pressure of 30 cm H2O). In this case the ventilator will deliver a lower tidal volume, rather than exceed the pressure limit. There are two solutions to this problem. 1) Increasing the inspiratory time allows more time for the set tidal volume to be delivered without exceeding the pressure limit. Initially, the Tinsp should change I:E ratio from 1:3 to 1:2. If this does not help an I:E ratio of 1:1 should be used. 2) If the above does not resolve the alarm reduce the tidal volume in one ml/kg IBW increments. This may be repeated every few minutes to a minimal tidal volume of 4 ml/kg IBW. The tidal volume should not be reduced below this. If a tidal volume of 4 ml/kg is necessary, medical staff should be made aware. � If the patient’s tidal volume is less than 6 ml/kg IBW, regular attempts should be made to increase it, in 1 ml/kg IBW increments, back towards 6 ml/kg. The ability to do this will be limited by the alarm “pressure limited, volume not constant” as described above. A tidal volume of 8 ml/kg may be used after discussion with the ICU consultant and documentation in the notes. � If the patient is receiving 6 ml/kg IBW, attempts should be made to reduce the inspiratory time to give an I:E ratio of 1:3.
Central Sydney Health Service Royal Prince Alfred Hospital ARTERIAL OXYGENATION GOAL Goal: SpO2 = 88 to 95 % or PaO2 = 55 to 80 mm Hg if ABG available � Adjust the FiO2 and PEEP according to the combinations outlined below. This can be performed every 5-10 minutes. � Adjustment to oxygenation can be made on SpO2 alone. It is not necessary to do blood gases to change FiO2. Blood gases should be performed as indicated. However, if a PaO2 is available adjustments are made based on it, rather than SpO2. Fi02 Peep 0.3 5 0.4 5 0.4 8 0.5 8 0.5 10 0.6 10 ARTERIAL pH and PaCO2 / EtCO2 Goal: pH = 7.30 – 7.45 0.7 � Leave the respiratory rate at the current settings Acidosis management: pH 7.10 – 7.30 � Increase the ventilator rate until pH > 7.30 or PaCO2 < 35 � PaCO2 is related to minute ventilation (MV = Vt x f) � Increasing f increases MV and “blows off” CO2 increasing pH � Maximum set ventilator rate is 35 bpm Acidosis Management: pH < 7.10 � Increase the set ventilator rate to 35 bpm 10 � If pH remains < 7.10, tidal volume may be increased in 1ml/kg IBW steps until pH > 7.10 Inform the senior register or duty consultant of an increase in tidal volume above 8 ml/kg IBW Alkalosis Management � Decrease the ventilator rate if possible 0.7 12 0.7 14 0.8 14 0.9 14 0.9 16 0.9 18 1.0 20- 24
Page 1: Central Sydney Health Service Royal
Page 5 and 6: Central Sydney Health Service Royal

CRITICAL CARE

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?