Fewer surgical-site infections seen with robotic radical prostatectomy

Chicago-Robot-assisted laparoscopic prostatectomy may be associated with significantly lower rates of surgical-site infection (SSI) than open radical retropubic prostatectomy, according to a large retrospective analysis of nearly 6,000 consecutive prostatectomies.

"Patients undergoing robotic prostatectomy are less likely to develop SSI than those undergoing open radical prostatectomy," said presenting author Matthew Tollefson, MD, a urologic oncology fellow at the Mayo Clinic, Rochester, MN. "Although the reasons for this improvement remain unclear, this is a provocative finding given the size of our database and the difference we found."

The research, presented at the 2010 World Congress of Endourology and SWL in Chicago, evaluated the rate of SSI in 4,908 open and 1,084 robotic prostatectomy patients. A total of 264 patients developed SSI, with a rate of 0.6% in the robotic group, compared to 4.3% in the open group. Development of bacteremia or sepsis from SSI, however, was the same at 0.1% in each group. Rates of urinary tract infection were also similar in the two groups.

Open prostatectomy involves a larger incision, with more tissue exposed to the air than the robotic approach. The open approach also requires the use of retractors, which can devitalize skin tissue, leading to poorer wound healing, noted Dr. Tollefson, who worked on the study with Matthew T. Gettman, MD, and colleagues.

Longer granulation period a cause?

Additionally, when an SSI necessitates the opening of the surgical wound, the granulation period is longer in the larger incision used in open surgery, resulting in a longer time to wound healing. However, further investigation into these and other possible causes of the difference in SSI rates are needed to further decrease the morbidity from prostatectomy.

The authors defined SSI as wound erythema or cellulitis requiring antibiotics or opening of the surgical wound within 30 days of surgery. Although many patients who had surgery at the Mayo Clinic did not return for follow-up, all patients were contacted after surgery for a health assessment. Patients were specifically asked about SSI during this follow-up.

Dr. Tollefson acknowledged that this method of determining rates of infection was less than ideal and represents a limitation of the study.

"We did not have wound culture results on many of our patients, and it is possible that some did not have true wound infections," Dr. Tollefson said. "It is also possible that some patients who did have infections may have been missed. However, these biases apply equally to both the open and robotic patients, so they should not affect the overall outcome that we found."