The new manager has moved swiftly in a bid to bring in reinforcements, reaching an agreement with Sao Paulo for striker Henrique subject to a work permit, in addition to making approaches for defenders Nedum Onuoha and Christopher Samba.
But Hughes highlighted the importance of knowing when to give up the ghost, and said: "We've made bids - not just for Chris Samba - and we'll see where that takes us. Obviously there comes a point where you need to draw a line under some deals because you don't think they are going to progress."
He added: "We'll have to look at each deal in isolation and make judgements on them as and when we feel need to walk away from things.
"At the moment, that is not the case with a number of situations but there is not much of the window left and we have to be mindful of that. If we want to do that, we have to do it very quickly."
One man on the west Londoners' radar is Manchester City's Onuoha.
Hughes managed the 25-year-old during the time at the Etihad Stadium and Press Association Sport understands a fee of between ?2.5million and ?2.75million has been agreed.
"We've obviously expressed an interest and I think it is progressing," he said. "I don't think we are at a point where we can confirm or really say it will definitely happen.
"We're hopeful but it has not been confirmed yet. I would like to think [we are closer to agreeing a deal].
"There has been conversations between both clubs and if we can make it happen we will be delighted."
Source: PA
Source: PA