Hypothermic nerve-sparing radical prostatectomy: rationale, feasibility, and effect on early continence

To report the first application of preemptive local hypothermia during robotic-assisted laparoscopic prostatectomy (hRLP) to attenuate inflammation. Surgical excision of the prostate during radical prostatectomy causes inflammatory damage to the surrounding neuromuscular tissues that could affect urinary continence.

Of 50 consecutive patients undergoing nerve-sparing hRLP (case numbers 668-717; 3 were excluded--2 underwent radiotherapy and 1 was withdrawn because of balloon failure), 47 were prospectively compared with a standard RLP cohort (case numbers 1-667). Pelvic cooling was achieved using cold irrigation and an endorectal cooling balloon cycled with 4 degrees C saline. The intracorporeal temperatures were measured. Continence was defined as 0 urinary pads. The Kaplan-Meier analysis of the time to 0 pads and multivariate Cox proportional hazards regression analysis was used to examine the group differences in continence after adjusting for the baseline characteristics.

The median temperature was 29.0 degrees C (endorectal cooling balloon only, range 24.4 degrees-35.9 degrees C) and 25.5 degrees C (endorectal cooling balloon plus irrigation, range 19.4 degrees-34.0 degrees C). The time to 0-pad status was determined in 590 of 667 controls (88%). The 3-month hRLP 0-pad rate was 86.8% +/- 5.8% and was 68.6% +/- 2.0% for the controls. The return to continence was faster for hRLP vs controls: median 39 days (range 0-110) vs 59 days (range 1-720), respectively (P = .002, log-rank test). A multivariate analysis adjusting for factors, including age, American Urological Association symptom score, abbreviated International Index of Erectile Function-5, body mass index, prostate weight, stage, nerve-sparing, and learning curve demonstrated a faster return to continence for the hRLP group relative to the control group (hazard ratio 1.66, 95% confidence interval 1.11-2.49, P = .014).

This study represents the initial application of local hypothermia to reduce the traumatic inflammatory sequela of RLP. Hypothermia was easily induced and safe and resulted in a statistically significant improvement in early postoperative continence.