Ventilator Flow Rates

  • Wednesday, October 19, 2016 6:58 AM
    Message # 4313041
    Deleted user

    I'm helping a small facility out that wants to add some medical air outlets to use a ventilator.  They only have a 3 x 3 manifold.  The ventilator is a GE Engstrom CS.  It says on the back it needs 160 lpm of oxygen and air.  This seems like a lot of air to me.  I know the sizing charts use 100 lpm.  Does this seem right to you?  

  • Thursday, January 05, 2017 1:40 PM
    Reply # 4509955 on 4313041

    Yes Chris, the Engstrom CS (Carestation) like most ventilators, does require at least 160 L/M for each gas and has a peak inspiratory flow rate of 180 L/M. That does not mean the gas consumption would be that high as inspiratory flow is approximately 1/3 of the respiratory cycle and depending upon the settings, the flow may vary during inspiration. There can be a huge difference between vent flow rates and actual volume of gas consumed. It would be rare for the vent to be used at the 21% 02 setting, which would require the inspiratory flow entirely from the med air source. That said, wall outlet flow must meet the vent (and NFPA 99 critical care) requirements. What I call “pneumatic capacitance” (another discussion altogether) would also play a part in the wall outlet flowrate.

    The best and most cost-effective solution for this facility would be to order the Engstrom CS with the optional on-board air compressor or if already purchased have the optional compressor installed in their existing vent(s). Then use the 3 x 3 manifold for emergency backup, with a good supply of med air cylinders in storage.

    A worst-case scenario, with one vent set at 21% 02 and with high patient minute volume, each side of the 3 x 3 air manifold could last a day or less, therefore in my view is not a good option. 


    Last modified: Thursday, January 05, 2017 1:46 PM | George Scott
  • Friday, January 06, 2017 6:08 AM
    Reply # 4512685 on 4313041

     George is right again as usual. It will suck up the air and the manifold is not large enough. 

  • Friday, January 06, 2017 3:29 PM
    Reply # 4513606 on 4313041
    Deleted user

    Just curious, is the GE Engstrom CS a specialty ventilator?

  • Saturday, January 07, 2017 8:55 AM
    Reply # 4514650 on 4313041

     Some are worse than others but they all consume gas.  Most of them you can buy within auxiliary air compressor.  The Philips unit will suck down a tank of oxygen in no time flat. 

  • Saturday, January 07, 2017 12:16 PM
    Reply # 4514877 on 4313041

     We had a country hospital with the same problem and they used ventilators from time to time and their source of supply was remote and not large enough.  We ended up putting in an oxygen generator that could produce oxygen continuously and that resolved the problem. 

  • Wednesday, January 11, 2017 4:09 PM
    Reply # 4542754 on 4313041

    Luke, not sure what is meant by specially ventilator. But, the Engstrom CS has many of the features found in other modern ventilators such as – requires high 02 and med air flow sources, optional on-board air compressor, programmable ventilation parameters, ventilation display screen, can administer aerosolized medications and provides continuous mechanical ventilation to a variety of patients. The Engstrom offers a neonatal ventilation option. Hope this helps.

    Link to User’s Manual here:


    Last modified: Wednesday, January 11, 2017 4:12 PM | George Scott

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