Complications from sling surgery are under-reported

"In a span of a couple of years, we saw and treated a significant number of patients with complications after this so-called 'minimally invasive' therapy," Larissa V. Rodríguez, MD, assistant professor of urology at UCLA, reported at the AUA annual meeting here.

"The number we had seen was almost as high as all of the cases presented in the literature combined. Therefore, either we were seeing all of the complications, which seemed highly unlikely, or there was a major discrepancy between the reported rates and true rates of complications after these procedures."

They queried the MAUDE database for all complications involving tension-free vaginal tape (TVT, Gynecare/Ethicon, Somerville, NJ), transobturator tape (TOT, Mentor Corp., Santa Barbara, CA), and the SPARC sling system (American Medical Systems, Inc., Minnetonka, MN) between 1999 and July 2005.

Complication rates likely higher

The investigators found that published studies on sling procedures consistently reported major complication rates to be <1%. But of the 869 slings reported in MAUDE, there were 33 "major vascular injuries" that led to two deaths, along with 38 bowel injuries leading to six deaths.

MAUDE also yielded 46 unrecognized bladder injuries, 26 unrecognized urethral injuries, 10 nerve entrapments, and two cases of necrotizing fasciitis.

What's more, UCLA itself had 26 patients referred to its medical center for treatment of major complications following sling placement (13 TVT, nine SPARC, four TOT). Twenty of those required removal of mesh from the urethra along with urethral reconstruction, while seven others underwent partial cystectomy to remove mesh from the bladder. Three others experienced urethrovaginal fistula, requiring repair with Martius flap.

"No sling is minimally invasive," Dr. Rodríguez told Urology Times. "Slings placed blindly with trocars can lead to devastating complications. Complication rates are likely much higher than those reported by companies or in the academic literature."

Because no national registry exists to track sling complications, the authors acknowledged there are no "true denominators in determining the [overall] complication rate."

Still, the investigators found 180 major complications in their search, compared with 51 from published series, many of which were published outside the United States. Large U.S. studies examined by the UCLA team contained only 11 major complications.

Dr. Rodríguez and her group attribute the discrepancy between reported and actual sling complication rates to "referral patterns and under-reporting, as well as surgeon experience."

Indeed, Dr. Rodríguez suggested that published studies on slings may come largely from major academic medical centers. Those centers, in turn, often have surgeons who perform a large number of the procedures. In their hands, complication rates may truly be low.

"But that doesn't seem to reflect what's happening in the community," Dr. Rodríguez said.