Consistency of environment is a key part of immersion in a scenario.

If the heroes have cleverly circumvented a spiked pit trap on their way into the dungeon by taking their time and being very careful, it's almost imperative on you to make sure that when they return through the same corridor they are running for their lives.

Transcript

[SFX]: Pow!
R2-D2: ... and, door totally chowned!
[SFX]: < boodit-ting-pow bleep-buzz >
C-3PO: Badly done, Artoo!
R2-D2: Uh oh, Nute's trying to regain control. I'll reroute him to—
[SFX]: < oowoo ooyoo-bippity doing ding boppy whiree zizang doop bleep ziku-ting doing >
[SFX]: Psssshh!!
{They run out onto the platform, troopers shoot at them}
[SFX]: Pow!
GM: Everyone with lungs: save versus poison at -4.
Chewbacca: What for? Oh... the alcoholic atmosphere. Last time you gave us a few minutes' grace.
GM: Last time you weren't running for your lives.
[SFX]: Pow!
Chewbacca: 15. Take that, noxious airs!
Leia: 1.
Leia: I'll drive! I'm ferpectly shober!
[SFX]: Pow! Pow! {Leia fires wildly with eyes half closed}
Chewbacca: But you've never piloted before.
Leia: Zigackly!