During a transurethral resection of the prostate (TURP) procedure, the surgeon uses a specialized instrument known as a resectoscope, which is inserted through the urethra, allowing for a minimally invasive approach. The resectoscope contains a camera, a light source, and a loop of wire that carries electrical current for cutting and coagulating prostatic tissue. This allows the surgeon to excise the obstructive parts of the prostate that are causing the blockage. The removed tissue is then flushed out using an irrigation fluid, and the procedure continues until the obstructive tissue has been adequately removed.
The electrical design of the loop decides which irrigant can be used. A monopolar loop sends current from the loop through the patient to a return pad, so the irrigant must not conduct electricity: glycine 1.5%, a sorbitol 2.7% with mannitol 0.54% mixture, or mannitol 5%. Glycine and the sorbitol-mannitol mixture are clearly hypotonic to plasma (glycine 1.5% has an osmolality of about 200 mOsm/kg), and mannitol 5% is nearly iso-osmotic but still electrolyte free, so all three dilute serum sodium when absorbed. A bipolar loop returns current through the instrument itself, so the field can be irrigated with 0.9% saline. Absorbed saline still expands the circulation and can cause fluid overload, but it does not dilute sodium or lower plasma osmolality, and the classic hyponatremic TURP syndrome is essentially eliminated. Laser procedures such as holmium laser enucleation (HoLEP) and photoselective vaporization (PVP) also run in saline.
TURP is typically performed under regional (spinal or epidural) anesthesia, though general anesthesia can also be used depending on the patient's condition and preferences. The procedure generally takes about 60 to 90 minutes, though this can vary depending on the size of the prostate and the complexity of the resection. The prostate tissue is resected in small chips, which are carried out through the resectoscope, leaving the remaining portion of the prostate in place while clearing the urethral passage. Patients often experience immediate relief of symptoms after the procedure, though full recovery may take several weeks.
