A/C vs. SIMV

[poppy07]

I'd like to hear your thoughts on ventilator modes. Which is best A/C vs. SIMV and in what cases. Trauma/Surg employs SIMV more often; MICU uses A/C almost always! I asked the fellow, and he said "you just make them work harder on SIMV." Let's see...

[joeyzstj, LPN]

What do you guys (US) call what I know as Pressure Control Ventilation plus Assist? It's a Draeger mode on the Evita models. It delivers breaths at a set rate, with a pressure limit. The breath is delivered until the pressure limit is reached, therefore the tidal volumes can change from breath to breath. The 'assist' part of it allows the patient to spontaenously trigger breaths, which are then delivered according to the pressure limit set. You can control the Tinsp on this mode as well which I understand you can't on SIMV on the Draeger ventilators.

So what is it called in the US?

Its referred to as Pressure Control or Pressure control plus assist here as well. If you understand ventilator marketing you know that with the exception of APRV, the companies essentially take the same 4 or 5 modes and tweak something small and give it a new name claiming that they have invented a new mode, when in reality its fundementally the same. Most pressure control modes allow you to manipulate Tinsp due to the fact that sometimes we need to flip the ventilation I:E ratio to an inverse ratio. You cant do this without prolonging I time and shortening E time.