Post-Operative Voiding Dysfunctions
By Kristin Jenkins

 QUEBEC CITY, Que. — As incontinence surgery moves towards more mesh surgery with minimally invasive slings, there is a significant trend in improved post-operative voiding dysfunction when compared to abdominal colposuspension techniques.

That’s the good news. The bad news is that patients undergoing synthetic sling placement can still develop obstructive voiding dysfunction right after surgery for a variety of reasons. What’s more, these patients require immediate attention – either for sling adjustment or intermittent catheterization— to avoid permanent bladder changes.

“The key is to counsel patients on the risks of potential post-operative voiding dysfunction and if it occurs, to support them through this period until it resolves,” Dr. Vincent Lucente told those attending Gynecology Quebec 2007.

Dr. Lucente is medical director, Institute for Female Pelvic Medicine & Reconstructive Surgery, New Orleans, LA.

Particular attention should be given to pre-operative voiding patterns, urodynamics and patient age as potential risk factors for dysfunction. “Set realistic expectations, both for the initial pelvic surgeries and management of post-operative voiding dysfunction,” advised Dr. Lucente.

Counselling on the risks of potential post-operative voiding is particularly crucial for the patient who has voiding dysfunction going into surgery. “This patient may have a risk for recurrent surgery,” noted Dr. Lucente.

Can post-operative voiding dysfunction be predicted? The risk is dependant on the type of surgical procedure as well as individual patient characteristics including:

* past history of urinary retention

* preoperative urodynamic pdetQmax‹15

* strains to void or completely void

* sphincter detrusor dysynergia

* PVR›100ml

* older than 70 years of age

Not only is post-operative voiding dysfunction a common concern following pelvic surgery for incontinence and prolapse, but the risk of voiding dysfunction significantly increases with concomitant prolapse surgery. Cleveland Clinic Outcome data ( 2006) show that when incontinence surgery is performed with prolapse surgery, the risk of post-operative voiding dysfunction is twice that seen with incontinence surgery alone.

Urodynamics is not a good predictor of what’s going on in voiding dysfunction but sometimes fluoroscopy can be helpful, said Dr. Lucente. It’s important to listen to the patient’s story and to use your gut feeling about what course of action is best.  “Ask the patient if the symptoms occurred around the time of surgery,” he said.

Clues to the cause of post-op voiding dysfunction can be taken from type of surgery and patient symptoms. Some patients experience urinary retention while others suffer from post-operative hesitancy and an intermittent, slower urine flow than before surgery. Obstruction, contractile dysfunction or both can cause all these symptoms.

“The challenge is to figure out how to manage it when you think it’s both,” noted Dr. Lucente, adding that most post-operative voiding dysfunction is a combination of obstruction and contractile dysfunction.

Obstruction usually presents as a sensation of bladder fullness, a normal urge to void and an inability to void. This is most often seen following pubovaginal sling surgery and is most commonly caused by excessive tension placed at the time the sling is secured, said Dr. Lucente. “Part of the ‘art’ to performing successful incontinence surgery is finding the balance between efficacy and voiding dysfunction,” he said. “You want the patient to stop leaking when she runs, jumps, coughs or sneezes but you don’t want to increase the risk of retention. You have to individualize the tape setting.”

Contractile dysfunction, on the other hand, usually presents as decreased sensation of bladder fullness with little or no urge and an inability to void. This is most commonly seen following prolapse surgery or surgeries involving more extensive dissection around the bladder. “If the sensory element is disrupted,” said Dr. Lucente, “chances are, so is the motor element. It’s important to put the whole picture together.”

Findings and symptoms of post-operative voiding dysfunction may include:

* elevated PVR

* decreased sense of bladder filling

* overflow incontinence (“classically seen post-partum in the ob/gyn world,” noted Dr. Lucente)

* interrupted or prolonged stream

* valsalva voiding

* positional voiding (“..when the patient pees like a bird dog by shifting forward on the toilet seat and tilting the pelvis to the side…”)

* de novo OAB

Following incontinence and prolapse surgery, all patients should receive a voiding trial, said Dr. Lucente. To pass, patients must empty more than half the bladder contents with a VR‹200ml.

Importantly, he added, “never let a weekend go down on a sling patient who has significant voiding dysfunction.” Voiding dysfunction due to outlet obstruction should be recognized within the immediate post-op period and treated accordingly.

Similarly, surgery release after synthetic slings should occur as soon as obstruction is identified.

“The clock is ticking,” said Dr. Lucente. “You get improved long-term outcomes in recurrent SUI if the sling can be released intact by pulling it down, within the first 7-10 days post-operatively. I would rather pull it than transect it later.” The longer the bladder is working under an obstructive scenario, he added, “the more likely you are to have bladder changes.” 

To prevent recurrent stress urinary incontinence (SUI), slings with biologic grafts should be released only after post-operative healing is complete, noted Dr. Lucente.

When to release? In the patient who has undergone an isolated TVT surgery or prolapse surgery with a concomitant TVT, consider release if voiding dysfunction does not resolve after 48 hours postoperatively and if the patient has “seemingly normal” sensation and/or urge with inability to void. “The longer you wait on patients who have voiding issues, the more the tissues are going to grow right into the fibres of the sling. It’s not going to loosen up over time,” said Dr. Lucente.

To release the sling, the patient is mildly sedated and local anesthesia is injected “at 3 and 9” to avoid edema. “Pull the sling slightly,” said Dr. Lucente. “If you pull it too far, you cannot push it back in. It’s about millimeters.” Ask the patient to cough. If nothing happens, pull the mesh a tiny bit more and ask patient to cough again. If you perceive “slight action…stop it right there,” said Dr. Lucente. “It’s not science but it is robust.”

Results of TVT release in a series of 1,175 women (Rardin et al. Ob Gynecol, 100(5)m 898-902, Nov 2002) show that of the 23 who developed persistent voiding dysfunction, 20 experienced complete relief of impaired bladder emptying. In addition:

* 4 reported complete relief of urge incontinence or urgency/frequency at 2 weeks (this decreased to 3 patients at 6 weeks); and

* 6 reported partial relief at 2 weeks and this increased to 7 patients at 6 weeks.

In the same review, looking at continence status compared with pre-TVT baselines:

* 14 women were considered cured at 2 weeks and remained cured at 6 weeks;

* 7 reported improvement at 2 weeks, down to 6 at 6 weeks; and

* 2 patients felt surgery had failed to improve their continence status at 2 weeks; this increased to 3 patients at 6 weeks.

The patient may judge success of a surgical procedure quite differently than it is judged by the surgeon, pointed out Dr. Lucente. “Patients may not be as wet as before surgery but they’re not exactly happy campers, either. They will go into the ‘failed’ category and wait for more surgery. Prospective longitudinal studies would be very helpful for this group, noted Dr. Lucente.

Contractile dysfunction —in which patients have little or no sensation to void despite a full bladder at the time of their voiding trial—occurs a few days post-operatively and can be treated with indwelling catheterization. This should be maintained until “normal” sensation of bladder filling occurs and the patient is able to pass an office voiding trial, said Dr. Lucente.

A review of 349 patients who underwent transvaginal mesh prolapse surgery at the Institute for Female Pelvic Medicine and Reconstructive Surgery showed that:

* 12 (3.4%) had post-operative voiding dysfunction

* 14 (4%) had de novo OAB

* 8 (2.3%) had de novo SUI