Comparing different pneumoperitoneum (12 vs. 15 mmHg) pressures with cytokine analysis to evaluate clinical outcomes in patients undergoing robotic-assisted laparoscopic radical cystectomy and intracorporeal robotic urinary diversion.

Background: Robotic cystectomy is the mainstay surgical intervention for treatment-refractory nonmuscle-invasive and muscle-invasive bladder cancer. However, paralytic ileus may complicate the postoperative recovery and may be a consequence of an inflammatory response associated with transient gut ischaemia. We have therefore investigated clinical, operative and inflammatory biomarker associations between paralytic ileus in the context of robotic cystectomy and intracorporeal ileal conduit urinary diversion. Methods: Prospective consective patients referred for robotic cystectomy were consented and included in the study, while patients >75 years old and converted to open procedure were excluded. The pneumoperitoneum pressure (PP) for carbon dioxide insufflation required to perform the procedure efficiently and safely was recorded (12 or 15 mmHg). We also recorded the postoperative days patients passed flatus and stools, whether they developed ileus, as well as other standard clinical and demographic data. The expression of select proinflammatory and anti-inflammatory cytokines was determined by multiplex analysis using a cytometric bead array with changes in profiles correlated with the pressures applied and with the existence of an ileus. Results: Twenty-seven patients were recruited, but only 20 were used in the study with 10 patients in each PP group. Seven patients were excluded all of whom had an extracorporeal ileal conduit formation. There were differences in the 40-min shorter operative time and 1 day shorter length of stay, as well as passing flatus 1 day and stools 1.5 days earlier in the 12 mmHg compared with the 15 mmHg group. More patients had ileus in the 15 mmHg group vs 12 mmHg group (30% vs. 10.0%). These were not statistically significant. Similarly, there were no statistical differences in the expression of proinflammatory cytokines at the two different pressures or between patient groups, but there were outliers, with the median indicating nonsymmetrical distribution. By comparison, anti-inflammatory cytokines showed some significant differences between groups, with IL-6 and IL-10 showing elevated levels postsurgery. No statistical difference was observed between pressures or the existence of an ileus, but the maximum levels of IL-6 and IL-10 detected in some patients reflect a pressure difference. Conclusions: The initial findings of this novel scientific study indicated a higher risk of paralytic ileus postrobotic cystectomy and robotic intracorporeal urinary diversion when a higher pressure of 15 mmHg is used compared with 12 mmHg. Although further studies are required to establish the linkage between cytokine profile expression, pressure and ileus, our initial data reinforces the advantages of lower pressure robotic cystectomy and intracorporeal urinary diversion in patient outcomes.

Serum cytokine levels as markers of paralytic ileus following robotic radical prostatectomy at different pneumoperitoneum pressures.

BACKGROUND: To evaluate intraoperative and postoperative cytokines in patients who underwent robotic prostatectomy (RP) at a pressure of 12 or 15 mm Hg, and the risk of postoperative ileus. MATERIALS AND METHODS: We presented the first series evaluating intraoperative and postoperative cytokines in patients undergoing RP at a pressure of 12 or 15 mm Hg by a single surgeon. Changes in cytokine concentrations were shown to correlate with surgical outcomes and pathological states. The study investigated the changes in cytokine concentrations (interferon-γ, tumor necrosis factor-α, interleukin-1ß [IL-1ß], IL-2, IL-4, IL-6, IL-12, and IL-17) at different pneumoperitoneum pressures and their potential role in the development of postoperative ileus. RESULTS: The data on 10 consecutive patients confirmed that a lower pneumoperitoneum pressure was associated with lower cytokine levels and a lower risk of ileus. There were increased levels of postoperative interferon-γ, tumor necrosis factor-α, IL-12p70, IL-1ß, IL-2, IL-4, and IL-17a at 15 mm Hg when compared to 12 mm Hg. CONCLUSIONS: The data indicated that lower pressure RP reduced intra-/postoperative cytokine levels confirming our hypothesis. Larger patient numbers are required to further validate this but the implications of this data will benefit not only urological patients but also other speciality patients undergoing minimally invasive surgery.