It is important to get to know how much intrathoracic pressure you can stand so that if need be you can release a little pressure at just the right moment before you quickly top-up your breath again.
I find that it is particularly important for me to keep a decent amount of pressure in my lungs when benching. I can manage a max of two or three reps when I am heavy benching (around 5RM) without taking a breath in between and I find that this enables me to keep my form really consistent. After the first two reps with no breath I take a small top-up breath right at the end of the concentric part of each subsequent rep until I am done. If I take a big breath between reps, I invariably find that my scapulae move from their adducted position (not all the way but at least a bit) which then changes the forces on my AC joints and eventually leads to AC joint pain (in my case).
If I am back squatting, I don't have a problem with form if I take a good breath between reps but I tend to hold my breath, again, until I am close to the end of the concentric part of each rep. If I am really struggling with a load, I will allow some air to escape as part of the fight to get the weight up.
Front squats with heavy loads are more like benching for me in that, if I release the pressure too much in my lungs, I find it hard to take a decent breath again between reps and will have more of a tendency to lean forward out of the hole.
Deadlifts and cleans allow for a decent breath between reps due to the reset when the bar is back on the floor. Same thing for Pendlay rows. RDLs do not have a reset between reps but, as the loads will probably be lighter than for regular deads, taking a breath at the top is not so much of an issue anyway.