Final answer:
Before undergoing a paracentesis, a patient with ascites should be instructed to empty their bladder to reduce the risk of bladder injury.
Step-by-step explanation:
The subject of this question is related to the preparation of a patient for a medical procedure called paracentesis, often performed to remove excess fluid from the abdominal cavity, a condition known as ascites. The correct instruction that should be given to the client before a paracentesis is that he or she needs to empty the bladder before the procedure. This is crucial to reduce the risk of bladder injury during the procedure.
Patients do not need to lay flat during the procedure, and they are typically awake, although they may be given a local anesthetic to numb the area where the needle will be inserted. No medication is usually injected into the body during a paracentesis except for a possible local anesthetic at the needle insertion site.