What causes acute urinary retention postop?

Many reasons: It may be related to anesthesia, medications, or the type of surgery you had. If the surgery was done near the bladder, you are more likely to have this problem. However, it is mostly temporary and will resolve. Occasionally, medication is used to help with this. You may also need to use the cathether until the problem resolves, either by intermittent self-catheterization or indwelling cath.