Fred Govier, MD
Virginia Mason Medical Center (Seattle, WA)

Overactive bladder (OAB) is a prevalent problem affecting an estimated 33 million patients in the United States. It is defined as urinary urgency with or without urge incontinence, usually with frequency and nocturia, in the absence of pathologic factors. It occurs in both males and females and the incidence increases with advancing age. There are multiple etiologies for OAB but in most patients the symptoms are caused by an abnormal contraction of the bladder that the patient interprets as urgency. If the contraction is strong enough, the patient suffers urge incontinence.

After taking a medical history and performing a physical examination, the clinician needs to rule out confounding factors such as urinary tract infections, incomplete bladder emptying, or hematuria that may indicate bladder pathology. When these studies are negative, the symptoms can often be managed by a combination of medications and behavioral modification involving limitations of fluid intake, avoidance of alcohol and caffeinated beverages and pelvic floor exercises (Kegels) to inhibit these abnormal contractions.

Patients refractory to the above measures, require referral to a specialist. In the past, pharmacologic refractory patients were managed with an abdominal sacrocolpopexy. This is an invasive surgical procedure in which a segment of bowel is harvested and attached to the bladder to increase capacity and eliminate these abnormal bladder contractions. While very successful, the procedure is invasive and the vast majority of patients are unable to void, requiring life-long intermittent catheterization. Even though we can now perform this procedure laparoscopically with much less morbidity, the surgery is still performed as one of our last options because of this inability to void.

Sacral Neuromodulation is a relatively new procedure that involves placement of a small electrode that stimulates the sacral nerves responsible for bladder sensory and motor function. The electrode is placed percutaneously under fluoroscopic control in a one hour operation. The patient tests the device at home with an external stimulator for approximately one week. If the device successful controls the overactive bladder symptoms, a small battery powered permanent stimulator is placed under the skin much like a cardiac pacemaker. The device is successful in 60 to 70% of the patients and the battery typically lasts five to seven years. Downsides of the procedure are mainly the high cost associated with the device itself and the fact that the electrode may migrate such that the stimulation is no longer successful. Several smaller simpler stimulators targeted to the tibial and pudendal nerves are currently in clinical trials.

Botulinum Toxin A or Botox® is recognized for its ability to selectively inhibit neural transmission to skeletal muscle and is widely used in the fields of dermatology and plastic surgery. Botox will also inhibit abnormal bladder contractions and prevent symptoms of overactive bladder and urge incontinence. The injections are performed in an office procedure with local anesthesia and the effects are immediate. Most investigators inject between 100 and 300 units in multiple injection sites over the floor of the bladder. The treatment appears effective in 60 to 70% of patients and lasts approximately four to six months. Downsides include the need for repeat injections, a small percent of patients who require temporary catheterizations and the fact that the drug is not FDA approved this indication so the patient must pay out-of-pocket.

The symptoms of overactive bladder and/or urge incontinence can range from being a mere nuisance to that of a devastating problem affecting all aspects of a patient’s life. With a brief history and physical examination, a few basic laboratory studies along with some medications and behavioral modification we can help the vast majority of patients. For those few refractory patients, we now have an ever increasing number of very successful minimally invasive treatment options.

Comments are closed.