Suprapubic catheterization refers to the placement of a drainage tube into the urinary bladder just above the pubic symphysis. This is typically performed for individuals who are unable to drain their bladder via the urethra. Suprapubic catheterization offers an alternative means to drain the urinary bladder when other methods are not clinically feasible, undesirable or impossible. Alternatives to suprapubic catheterization include urethral catheterization, intermittent catheterization, urinary diversion and percutaneous nephrostomy drainage. These specialized drainage catheters are typically placed either percutaneously or openly. Percutaneous access commonly employs visualization using cystoscopy.
The urinary bladder is a hollow organ made of muscle designed to store and evacuate urine from the human body. A typical urinary bladder holds between 300 and 500 ml. The bladder is divided into the fundus, body, apex, and neck. The urinary bladder is located behind the pubic bone in the extraperitoneal space. The extraperitoneal space anterior to the bladder is referred to as the prevesical space or space of Retzius. The space is named after Anders Retzius (1796-1860) the Swedish anatomist who first described this area.
The abdominal wall just above the pubis is comprised of the rectus muscle bellies lateral and the linea alba in the midline. Below the arcuate line, the aponeuroses of the external oblique, internal oblique and transversals muscles run anterior to the rectus muscle. It is through this area by which open access to the dome of the bladder is obtained. The dome or cephalad most portion of the bladder is covered with perineum. The urinary bladder is supported below by the pelvic diaphragm. Suprapubic drainage tubes commonly exit via a midline site, but off center (through the rectus) is also acceptable depending on the patient’s body habitus.
The most common indication for suprapubic tube placement is for urinary retention when urethral catheterization is not feasible. This can include severe BPH, false urethral passages, morbid obesity, urethral strictures, bladder neck contracture and genital malignancy. Urogenital trauma causing urethral disruption and severe damage are common indications. Suprapubic tube placement for the long-term diversion of urine in cases of neurogenic bladder is also sometimes indicated.
Contraindications to suprapubic cystotomy are relatively few, and they depend on the approach being utilized. Percutaneous approaches are contraindicated in a non-distended bladder, and in the setting of bladder malignancy. The former places the patient at substantial risk of inadvertent bowel or vascular injury. Relative contraindications for suprapubic cystotomy include whether open or percutaneous include active skin infection, coagulopathy, osteomyelitis of the pubis, and orthopedic hardware of the pubic symphysis.
Equipment utilized for the placement of a suprapubic catheter varies by technique. Typically, standard Foley catheters are used for drainage catheters. The open technique utilizes standard surgical instrumentation including a small self-retaining retractor such as a Weitlander retractor and dissolvable suture for closure of the cystotomy. Percutaneous (Seldinger) technique requires the use of a large-bore needle, a guide wire and peel away catheter insertion sheath. These are commercially available as an all-in-one kit. Percutaneous approaches are often performed under vision with a rigid or flexible cystoscope. Finally, a specialized retractor called a Lousley prostatic retractor can be used to assist in an open tube placement. Portable ultrasound devices are also helpful to confirm tube location.
Suprapubic catheterization is performed by a urologist, a surgeon who specializes in the genitourinary system. Other practitioners that may perform this procedure include general surgeons, gynecologists, urogynecologists, as well as emergency providers such as emergency room physicians and trauma surgeons.
Suprapubic catheterization can be performed with local or general anesthetic depending on the situation. The lower abdomen is shaved and prepped with standard surgical prep. If the technique will involve entrance via the urethra, the genitals are prepped and draped accordingly. If rigid cystoscopy is required, the patient should be positioned in dorsal lithotomy. Flexible cystoscopy can easily be performed supine in most cases. The patient should always be placed in Trendelenburg position is help minimize the risk of bowel injury.
Several techniques are well described for the placement of a suprapubic catheter. Two categories exist; these are open technique and percutaneous technique. Variations of each of these exist, and many are hybrid techniques.
Open cystotomy involves a small, typically transverse incision roughly 2 fingerbreadths above the pubic symphysis. The bladder ideally is filled prior, this aids in the identification of the bladder. The rectus fascia is opened allowing access into the preperitoneal space. The bladder is identified, and dissolvable stay stitches are placed on either side of the intended cystotomy. A small cystotomy is then made, and the drainage tube is placed. The tube is secured to the bladder with a dissolvable purse-string stitch. The facial layers and skin are then closed around the tube which is finally secured to the skin with a temporary stitch.
Percutaneous Seldinger technique is also fairly common. Distention of the urinary bladder is imperative for this approach. This can be done physiologically (urinary retention) or with the aid of a cystoscope. Cystoscopic examination allows direct visualization of the puncture needle but is not required. In an area, roughly 2 fingerbreadths above the pubis, a large bore needle is inserted until urine returns. A guide wire is then advanced into the urinary bladder. This tract is then dilated to accommodate a pull away sheath. The suprapubic catheter is then passed into the bladder via the access sheath which is later removed. The catheter is then secured similarly.
The Lousley prostatic retractor can be utilized for a modified open approach. This specialized instrument is passed per the urethra into the urinary bladder. Upward pressure is then applied bringing the instrument and bladder dome taught to the abdominal wall. Suprapubic cut down is then performed exposing the retractor tip. The urinary catheter is then attached to the Lousley prostatic retractor which is retracted back into the bladder and removed.
Trocar kits are also available for direct puncture into the urinary bladder. These are used less frequently as they can have an increased risk of injury to adjacent organs. Several commercially available kits are available for the percutaneous technique which tends to be the most common approach.
Early complications of the operation include inadvertent bowel injury, bleeding, vascular injury, obstruction of the tube, and failure to enter the bladder during the initial procedure. Bowel injury can be limited with the use of preoperative imaging as well as intra-operative ultrasound. Other late complications include refractory hematuria, urosepsis, wound infection, bladder stones, tube calcification or malfunction, and loss of the cystotomy tract. In patients with a chronic obstruction such as BPH, decompression of the bladder can result in post-obstructive diuresis. This is defined as urine output greater than 200 mL per hour. This brisk diuresis is a physiologic response to the volume expansion that takes place with chronic obstruction. Another late complication is chronic irritation of the bladder secondary to the tube. This is considered a risk factor for squamous cell carcinoma of the bladder. Finally, while not a surgical complication in the true sense of the term body image alteration can later become a patient concern.
Suprapubic catheters provide an alternate method to drain the urinary bladder. These are commonly utilized to manage bladder dysfunction and urinary retention not amenable to urethral catheterization. Like all urinary catheters, they have risks and benefits. Current literature is mixed concerning the risk of urinary tract infection. Some studies have suggested that limiting genital contact with the catheter may decrease symptomatic infection rates. However, other series have not supported this conclusion. Urethral catheters have obvious limitations on a patients sexual function, making suprapubic tubes potentially more appealing to those sexually active. Access for catheter exchange is a common consideration when choosing bladder drainage. Suprapubic tubes allow for more convenient tube exchanges based on their location. Furthermore, chronic urethral catheters carry the risk of urethral erosion over time, particularly in males. Urinary incontinence is often a consideration when considering bladder catheterization. It is important to note that urinary incontinence by the way to the urethra can occur despite suprapubic drainage. This is of particular concern when skin breakdown from bladder incontinence is present. Leakage around the suprapubic tube can also occur.
Suprapubic catheters can be placed for certain surgical procedures. These can provide stable bladder drainage before and after complex urethral reconstructions. Additionally, they can be combined with a urethral catheter to provide a means for continuous irrigation. Irrigation inflow can be instilled through a suprapubic catheter and outflow by way of the urethral catheter, or vice versa. In patients undergoing bladder, prostate or urethral surgery these tubes can be a valuable tool to maintain adequate urinary drainage.
A multidisciplinary approach to suprapubic catheters
Suprapubic catheterization is sometimes needed when drainage via the urethra is not possible. While the procedure is usually performed by a urologist, the nurse is usually in charge of monitoring the catheter and the urine output. Nurses need to know the potential complications of this procedure such as bowel injury and must regularly examine the abdomen. In addition, the patient needs to be monitored for signs and symptoms of a urinary tract infection. Finally, a common problem with suprapubic catheterization is leakage at the skin site and hence the nurse should monitor the skin site for incontinence.