Objectives:

  • Describe the physiology of oxygenation and ventilation

  • Discuss the diagnosis and treatment of ARDS

  • Apply one’s knowledge of basic ventilation mechanics in simulated ventilator cases

Theory:

Additional Lung Physiology Resources:

Life in the Fast Lane has a wonderful series on the basics of ventilators. To the left is the first video, please go to their post to watch how to use a ventilator.

Life in The Fast Lane: Ventilators

While you watch them, try to connect the topics from the breathing physiology power point to the mechanics of a ventilator.

  • PEEP/EPAP = Increasing surface area = better oxygenation

  • IPAP = increased tidal volumes and MV = better ventilation

  • FiO2 = increased partial pressure of O2 = more O2 diffusion

  • Respiratory Rate = increased MV = better ventilation

Ventilation Simulator Cases:

 Download the Hamilton C6 Ventilator Simulator

Above is a link for a Hamilton C6 Ventilator Sim. This is a very powerful tool to practice making changes and seeing how a patient would respond. (There is also an iPad App which you can use).

Normal Patient

Normal Patient

How to practice:

  • Start the simulator with a normal patient on PCV+ and look at the parameters. Familiarize yourself with the things you can see and change.

  • By clicking on the dials on the right, you can change the IPAP (Pcontrol), PEEP, FiO2, and respiratory rate.

    • Predict what you happen if you increase the IPAP, change it and see if you were right

    • Senior - ask your interns what a normal minute ventilation is, what is a normal tidal volume?

    • Once you have familiarized yourself, and have the patient on good settings, check an ABG (click the blue button in the bottom right corner of the screen -> syringe)

  • Next. Keep the settings as it and change the patient to ARDS 2.

    • Don’t change any of the settings yet, but watch the changes on the vent.

      • Check an ABG

      • What happened to the SpO2? why?

      • What happened to the TV and Minute Volumes? why?

      • What would you change to improve the SpO2 and Ventilation?

        Try it out, check an ABG, see if it helps.

While you are using the simulated patients in the program keep in mind what your goals are for ARDS vent management:

  • Tidal Volume: 4-6ml/kg of Ideal Body Weight

  • Plateau Pressure <30

  • Permissive Hypercapnia pH > 7.25

  • Oxygenation Goals: PaO2 55-80, SpO2 88-92%

    • FiO2 < 70% if able, increase PEEP to manage

Additional ARDS Reading:

Discuss Your Questions Here:

Related MKSAP 18 Questions:

Pulm 10
Pulm 58
Pulm 53
Pulm 70
Pulm 80