Like everyone said, it depends on a few things:
1) Ability - If you are more of an advanced skier, you will be able to handle a burlier ski.
2) Weight - At 145 lbs, you are pretty light.
3) SKI - You haven't told us what ski it is. If it is a stiff 181, that might be too much ski for you. If it is a softer 181, you might be OK.
4) Mounting Point - If it is a park ski, and you center mount them, it is much different than an all-mountain ski where you are going to mount -3 or -4