opiates and large Vts

hmmm,

The only thing that is coming to my mind is with CABG pt's. These pt's might have a lower tidal volume and pain is the limiting factor with them. So, by giving them an opiate and relieving the pain, they're able to breathe deeper.

Other than that, Im not aware of anything.

hmmm,

The only thing that is coming to my mind is with CABG pt's. These pt's might have a lower tidal volume and pain is the limiting factor with them. So, by giving them an opiate and relieving the pain, they're able to breathe deeper.

Other than that, Im not aware of anything.

Thank you for replying but no sorry, I meant pts who are sedated and ventilated without a pain factor. I've been told several times that the opiates are causing the large tidal volumes (volumes of 900 1000mls for a 65kg person) but have failed to get a decent explanation why this might be the case.

I thought opiates/narcotics can cause hypoventilation by decreasing respiratory drive (rate) and shallower breaths (thereby lowering the Vt)?

a one liter Vt is no bueno on a 65kg vent pt.....:uhoh21:

In the spontaneously breathing patient, opiates cause a decrease in respiratory rate with an increase in tidal volume. Unless your patients that are intubated are on SIMV or PSV and breathing on their own, opiates shouldn't alter their respiratory pattern. Now, if they are breathing on their own with just ventilatory support, yes, they will take larger volumes at a slower rate.