What to do when blinds get big and small stacks to your left?

[Mr.Poker]

My question is a fairly simple one, but one i'm never too sure how to adjust to.

Say you are a medium sized stack and the blinds are increasing, you want to increase your aggressiveness to accumulate. However, when there are smallish stacks in the blinds when you are in LP, what is your move?

Should you be loosening your range or tightening it, given that if you raise and they push, you are committed to calling.

My instincts say that you should tighten your range for the smaller stacks and target the medium stacks, however while the small stacks remain behind you, the threat of them pushing over you constantly remains.

How does your strategy change with these small stacks and increasing blinds?