Wound Vac!

I have a question about the famous wound vac. I've been told people put opsite over the wound, then the foam, then another opsite. I've also been told you can put the foam directly on the wound bed without the opsite first, but I know it will stick to the wound and might cause the PT to need a debreeding to remove the black specks. My question is, what do you do personally and what are your experiences with wound vacs? They're really cool to apply and I've seen them work wonders. Also, if there is a tendon showing in the wound, would that make the wound vac contradictory?
I first apply Hydrogel or water-soluble lubricant to the wound bed to keep the foam from sticking, then I place foam on top of the wound, then I cover everything with the transparent opsite drape.

So basically you can use the opsite under the foam if you choose to?

No, you really should not use an op site directly against the wound, then sponge. The sponge is what is "soaking" up the fluid part of the wound. If you were to put an op site against the wound, it would be air/fluid tight, hence discounting what you are trying to accomplish by having a wound vac on. It impedes the suction aspect.If you are finding black specs in the wound (and make sure when you are cutting the sponge, it is with sharp scissors to try and not have that happen) a water based gel can help with that. But make sure that is part of your order.Sponge to fit, the op site over with a small slit in it, the machine, then a larger op site to keep it all in place.You do not want a water/air proof barrier between the wound and the sponge.And there's a lot of education/videos that manufacturers have on their models. Some on you tube.

Everyone is telling me different things and I just want to know the clear cut way it is done by the book. I've seen it done both ways. I thought the op over the wouND would defeat the purpose of the filtering of that wound... I don't know I'm just confused and can anyone answer my tendon question?