Final answer:
Distilled water is not used for irrigation during a TURP procedure because it can cause electrolyte imbalance.
Step-by-step explanation:
The use of distilled water during a highly invasive genitourinary procedure such as a transurethral resection of the prostate (TURP) is prohibited for irrigation because of the potential for electrolyte imbalance. Distilled water lacks minerals and electrolytes that are essential for maintaining the balance of fluids and electrolytes in the body. Using distilled water for irrigation can disrupt the electrolyte balance, which can have serious consequences on the patient's health.