Transurethral Resection and Transurethral Incision of the Prostate

Indications

Transurethral resection of the prostate (TURP) has played a storied role in American urology. Many of the same individuals who were crucial players in establishing the specialty of urology also played important roles in the development of and widespread training of residents to perform TURP. Although the number of procedures performed has decreased in recent years, TURP was probably the most important urologic surgical procedure in the 20th century. Medical therapy, improved understanding of the indications for intervention, and office-based therapy options have decreased the frequency of TURP treatment of benign prostatic hyperplasia (BPH). Nevertheless, TURP remains the gold standard treatment for bladder outlet obstruction caused by BPH. This is the technique to which all other therapies are compared. Indeed, TURP produces the largest decrease in urinary symptoms, the largest increase in urinary flow rate, and the largest decrease in urodynamically measured voiding pressure of any therapy.

Transurethral incision of the prostate (TUIP) is another endoscopic treatment alternative for patients with bladder outlet obstruction but who do not have substantial BPH. This procedure has been discussed for more than 100 years; however, the first modern series of patients was published by Orandi in 1973. In TUIP, no tissue is actually removed, but one or more incisions are made from inside the bladder neck to the prostatic verumontanum. This allows the bladder neck and prostate tissue to separate, functionally widening the channel through the prostatic urethra. TUIP is a technique ideally suited for younger individuals without significant prostatic hyperplasia but with urodynamically proved primary bladder neck obstruction. These individuals often have cystoscopic findings of a high bladder neck without significant lateral lobe hyperplasia. TUIP also is useful as a lesser invasive technique for those with bladder outlet obstruction from BPH. General belief among resectionists is that TUIP may be considered when the prostatic gland size is less than 30 g. Although this cutoff in prostatic size seems reasonable, no clinical series has demonstrated 30 g to be the upper limit of size. TUIP is probably not the best choice when the patient demonstrates an enlarged median lobe of the prostate. The obstructive median lobe remains after TUIP and often also prevents the bladder neck from springing apart adequately. TUIP is an effective therapy in appropriately selected patients but has not earned the moniker of a gold standard therapy. Questions remain about optimal technique, appropriate prostate size, and long-term durability.

Preoperative Management of TURP and TUIP

The patient is given a single dose of perioperative intravenous antibiotics before beginning the resection. Consideration should be given to broader and longer antibiotic coverage for the patient in total urinary retention whose urinary tract is likely colonized because of prolonged urethral catheter drainage. Several clinicians have advocated the use of a 5α-reductase inhibitor for at least 1 month before therapy. This has been examined in a few clinical studies and not found to be significantly helpful. Most resectionists do not routinely use a 5α-reductase inhibitor before TURP.

TURP and TUIP can be performed with either general or spinal anesthesia. As recently as 1989, 79% of procedures were performed under spinal or epidural anesthesia. Regional anesthesia was the preferred method in the past because an awake patient facilitated earlier diagnosis of dilutional hyponatremia. Evolution in operative technique and equipment has made dilutional hyponatremia less of a problem. Bipolar electroresection eliminates the possibility of hyponatremia in that the technique uses normal saline irrigant during the procedure. Also, many surgeons now use less aggressive tissue resection. Less aggressive resection leading to less irrigant absorption also lowers the possibility of dilutional hyponatremia. Given either of these methods, general anesthesia can be a good anesthetic choice and is most commonly used today.

Patient Positioning

The patient is placed on the edge of the operative table in the dorsal lithotomy position. Locating the perineum at the bottom edge of the operative table is important to allow the resectoscope to be angled upward for access to anterior prostatic tissue. An O’Connor drape can be placed to facilitate prostatic elevation by transrectal compression if one believes this helpful. It is not useful for TUIP. Skin preparation and placement of surgical drapes is routine.

TURP Surgical Procedure

Careful cystourethroscopy to visualize the entire prostatic and bladder urothelium should be performed before cutting is begun. The presence of other lesions such as bladder tumor, lithiasis, or stricture must be excluded. After the entirety of the bladder has been visualized, the resectoscope sheath can be passed into the bladder using either the blunt tip or visualizing obturator. Passage of a resectoscope sheath without an obturator should not be attempted. Some patients require gentle dilation of the meatus and fossa navicularis with well-lubricated Van Buren sounds before the resectoscope can be passed smoothly. In the absence of overt stricture disease, sequential dilation from 18 Fr to a size 2 Fr larger than the chosen resectoscope sheath is sufficient. Adequate urethral dilation and periodic lubrication of the resectoscope sheath are necessary to minimize development of postoperative urethral stricture disease.

Several devices are available for removing prostatic tissue. These range from traditional cutting loops to rollers, roller balls, and buttons. Cutting loop options are available for either monopolar or bipolar electrosurgical cutting and coagulation. These can be subdivided into the traditional “thin loops,” which are firm wires, and “thick loops,” which can be up to several times the diameter of the thin loops. Thin loops have higher current density and cut more cleanly but do not coagulate blood vessels as well as thick loops. Increasing the electrosurgical generator output can compensate somewhat for the increased tissue drag experienced when using a thick loop. One typically can begin resection on power settings of 70 cut and 70 coagulation when cutting with a thin loop. Power output can be increased as needed when using a thicker loop.

Rollers, roller balls, and buttons remove prostatic tissue by desiccation. The device is passed over tissue with a light pressure extended into the prostate. Higher power settings are necessary when using these devices. Prostatic tissue is desiccated and carbonized, leaving only a small volume of residual tissue. These devices require longer treatment sessions for larger glands but generally offer better coagulation than loop electroresection. Choice of device is largely based on personal preference rather than clinical data.

TURP Technique

Some patients with bladder outlet obstruction due to BPH have substantial median lobe enlargement ( Figs. 67.1 and 67.2 ). If this is the case, the median lobe requires early resection to permit irrigation of prostatic chips out of the operative field ( Fig. 67.3 ). Typically, the median lobe is resected down to the point where circular bladder neck fibers are encountered. At this point, the bladder neck and prostatic fossa are flat with the bladder floor that extends from the trigone ( Fig. 67.4 ). Overresection of this area may undermine the bladder neck and should be avoided. After the median lobe has been resected appropriately, the resection continues in the floor of the prostate to the proximal aspect (bladder side) of the verumontanum. The verumontanum is the key landmark used during resection of the prostate and should not be resected ( Fig. 67.5 ).

After the bladder neck and prostatic floor have been resected, then attention can be turned to the anterior prostate. Many individuals have only a small amount of anterior tissue. Resection begins just inside the bladder neck and continues to a point near the verumontanum. The scope is positioned at the verumontanum, rotated 180 degrees without any in or out movement, and anterior tissue is resected. Accidental movement of the scope distal (outward) can lead removal of tissue distal to the verumontanum. One is best served by waiting until the end of the procedure to complete the most distal (apical) resection. Often only one or two loop depths are required in the anterior portion of the prostate.

After the prostate has been opened by the initial resection at the 6 and 12 o’clock positions, one can begin taking down the lateral lobes. The resectionist should perform the procedure the same way every time in order to develop a style that is thorough and repetitive. One typically begins at the 6 or 12 o’clock position and resects from the bladder neck for one loop length. An experienced resectionist will rotate the scope slightly to position for the next loop pass without advancing or withdrawing the scope after each pass ( Fig. 67.6 ). On small prostates, this may be the entirety of the prostate. Larger prostates, however, may require multiple loop lengths ( Fig. 67.7 ). In that case, one should resect the first loop length all the way around 360 degrees. After this is done to near the appropriate depth, one can progress more distally. It should be noted that if the prostate is extremely large, care should be given not to resect too deeply and to open venous sinuses early in the case ( Fig. 67.8 ). These can, under the pressure of the irrigating fluid, lead to absorption of large amounts of irrigant fluid. If one is using saline as the irrigant, this leads only to volume dilution, but if one is using glycine or sterile water as the irrigant, profound dilutional hyponatremia may result. Venous sinuses are usually encountered when the resection extends down to near the surgical capsule. The character of the prostate tissue usually changes when the surgical capsule is encountered. The foamy prostate tissue becomes more stromal and fibrous ( Fig. 67.9 ). One then progresses distally until the distal aspect of the loop length reaches the proximal verumontanum. Short scalloping resection “bites” are to be avoided. Long loop lengths of appropriate depth leave a smooth prostatic fossa. Avoid coagulating small bleeding vessels in tissue that will be soon resected. At this point, one should complete the resection of the lateral lobe tissue and develop thorough hemostasis.