Prolonged warm ischemia, increased blood loss, and solitary kidney status predict post-surgical complications.
Orlando, FL-In what may be the largest study of its kind, a Cleveland Clinic team has looked at 507 laparoscopic partial nephrectomies (LPNs) conducted between 1999 and 2006 to identify factors that increase the risk of postoperative complications.
The factors found are similar to those related to complications appearing in the standard open procedure for partial nephrectomy: prolonged warm ischemia, increased intraoperative blood loss, and conducting the procedure in patients with solitary kidneys.
"There have been no significant studies of the risk factors associated with postoperative complications, at least none of this size," said Rodrigo Frota, MD, formerly a Cleveland Clinic fellow working with Inderbir S. Gill, MD, Burak Turna, MD, and colleagues.
Of 507 LPN procedures, 93 patients (19.7%) presented with 107 postoperative complications, Dr. Frota, who is now a urologist at General Hospital of Bonsucesso, Rio de Janeiro, Brazil, reported at the AUA annual meeting. Forty-nine (9.7%) of these were urologic, and 58 (11.4%) were non-urologic. In terms of severity, 20.6% were grade I complications, 45% were grade II, 30% were grade III, and 4.7% were grade IV. There were no grade V complications.
Dr. Frota explained that patients with a single kidney might be considered at greater risk for complications because LPN is conducted with greater deliberation in these patients, and the slower, more considered pace of the procedure might actually increase risk.
This study spanned nearly 7 years of procedures. Researchers broke the study into two 3.5-year periods to determine whether complications were more frequent in the earlier, or learning years, or in later years when more challenging presentations were being treated. Surprisingly, there was little difference in complication incidence between the two periods. Indeed, the researchers reported that the incidence of complications actually decreased as the team tackled the more challenging presentations.
"The warm ischemia time actually decreased despite the increased complexity," Dr. Frota told Urology Times.
The time span of this study reflected the growing use of LPN. A total of 130 procedures were conducted between 1999 and 2002, compared to 387 procedures conducted between 2003 and 2006: almost a 300% increase in the overall number of procedures between the two periods. The authors also reported a 132% increase in the number of complex tumors treated in the latter period.
Results, experience correlated
A moderator of this podium presentation cautioned the audience about translating the results of the study too literally to all practices. He observed that all procedures reported in this study had been performed by Dr. Gill, who is considered a leader in the field of laparoscopic surgery. The moderator suggested that individuals with less experience might see different results.
"About 5 years ago, laparoscopic partial nephrectomy was conducted only by surgeons with substantial experience, those who practiced at larger institutions. Today, an increasing number of surgeons have adopted the procedure and are conducting increasingly complicated surgeries, but there is still a learning curve," Dr. Frota agreed.
"Surgeons who are just starting must select patients carefully. They should perhaps begin with small, peripheral tumors. But for those with experience, there may be no limits.
"Still, the goals continue to be to continue to reduce warm ischemia times and blood loss," he said.