Clinical outcomes of low-pressure pneumoperitoneum in minimally invasive urological surgery

Postoperative ileus-Immune mechanisms and potential therapeutic interventions

BACKGROUND

Postoperative ileus (POI) is a condition marked by a temporary suppression of gastrointestinal motility following abdominal surgery. The mechanism of POI encompasses various factors and is characterized by two phases: the early neurogenic phase involving both adrenergic and non-adrenergic neural pathways; the later immune-mediated phase is characterized by a sterile inflammatory response that lasts several days. Activation of muscularis macrophages triggers a sterile inflammatory process that results in dysfunction of the enteric nervous system (ENS) and a reversible inhibition of gastrointestinal motility.

PURPOSE

In this minireview, recent insights in the pathophysiological mechanisms underlying POI and potential new therapeutic strategies are described.

Perioperative and functional outcomes of single-port versus multi-port robotic-assisted radical cystectomy: evidence-based on controlled studies

To compare perioperative outcomes of robot-assisted radical cystectomy (RARC) using a single-port (SP) or multi-port (MP) robotic platform. We conducted a comprehensive search of the PubMed, Web of Science, Scopus, and Google Scholar databases until June 2024. For a combined analysis of the data using random effects, Review Manager 5.4 was employed. To compare continuous and categorical variables, the weighted mean difference (WMD) and odds ratio (OR) were employed, respectively. Three original studies were included, comprising a total of 170 patients (SP-RARC: 73 versus MP-RARC: 93).Recovery of bowel function was faster in SP-RARC (WMD -1.02 days, 95% CI - 1.33 to - 0.17; p < 0.001), and lymph-node yield was lower than in MP-RARC patients (WMD - 6.32, 95% CI - 8.90 to - 3.75; p < 0.00001).There were no significant differences between the SP-RARC and MP-RARC groups in terms of other perioperative outcomes such as surgery duration, length of hospital stay, estimated blood loss, major complication rate, positive surgical margin rate, readmission rate, and recurrence rate. The SP robot offers a safe alternative surgical approach to RARC, providing similar postoperative outcomes compared to the MP robot. The SP system remains an attractive option that will require longer follow-up and cohort validation in the future.

Robot-assisted Partial Nephrectomy Using Intra-arterial Renal Hypothermia for Highly Complex Endophytic or Hilar Tumors: Case Series and Description of Surgical Technique

Background

In partial nephrectomy for highly complex tumors with expected long ischemia time, renal hypothermia can be used to minimize ischemic parenchymal damage.

Objective

To describe our case series, surgical technique, and early outcomes for robot-assisted partial nephrectomy (RAPN) using intra-arterial cold perfusion through arteriotomy.

Design setting and participants

A retrospective analysis was conducted of ten patients with renal tumors (PADUA score 9-13) undergoing RAPN between March 2020 and March 2023 with intra-arterial cooling because of expected arterial clamping times longer than 25 min.

Surgical procedure

Multiport transperitoneal RAPN with full renal mobilization and arterial, venous, and ureteral clamping was performed. After arteriotomy and venotomy, 4°C heparinized saline is administered intravascular through a Fogarty catheter to maintain renal hypothermia while performing RAPN.

Measurements

Demographic data, renal function, console and ischemia times, surgical margin status, hospital stay, estimated blood loss, and complications were analyzed.

Results and limitations

The median warm and cold ischemia times were 4 min (interquartile range [IQR] 3-7 min) and 60 min (IQR 33-75 min), respectively. The median rewarming ischemia time was 10.5 min (IQR 6.5-23.75 min). The median pre- and postoperative estimated glomerular filtration rate values at least 1 mo after surgery were 90 ml/min (IQR 78.35-90 ml/min) and 86.9 ml/min (IQR 62.08-90 ml/min), respectively. Limitations include small cohort size and short median follow-up (13 [IQR 9.1-32.4] mo).

Conclusions

We demonstrate the feasibility and first case series for RAPN using intra-arterial renal hypothermia through arteriotomy. This approach broadens the scope for minimal invasive nephron-sparing surgery in highly complex renal masses.

Patient summary

We demonstrate a minimally invasive surgical technique that reduces kidney infarction during complex kidney tumor removal where surrounding healthy kidney tissue is spared. The technique entails arterial cold fluid irrigation, which temporarily decreases renal metabolism and allows more kidneys to be salvaged.

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.

Perioperative and oncologic outcomes of transperitoneal versus retroperitoneal laparoscopic nephroureterectomy for upper urinary tract urothelial carcinoma: a systematic review and pooled analysis of comparative outcomes

BACKGROUND

The debate on whether to choose a transperitoneal (TP) or retroperitoneal (RP) approach for treating upper urinary tract urothelial carcinoma (UTUC) with laparoscopic surgery has been drawing attention. This study aimed to systematically review and meta-analyze the existing evidence regarding oncologic and perioperative outcomes of transperitoneal laparoscopic radical nephroureterectomy (TLNU) and retroperitoneal laparoscopic radical nephroureterectomy (RLNU) in managing UTUC.

METHODS

A comprehensive literature search was conducted using PubMed, Scopus, Embase, and Google Scholar for identifying randomized controlled trials (RCTs) and observational studies that evaluated the outcomes of TLNU and RLNU for UTUC. Continuous variables were represented by weighted mean difference (WMD) and standard mean difference (SMD), while binary variables were represented by odds ratio (OR), with 95% confidence intervals (CIs). The quality was assessed using the Newcastle-Ottawa scale. A sensitivity analysis was performed to evaluate the robustness of the estimates.

RESULT

Six observational studies were incorporated into this meta-analysis. The overall TLNU was associated with significantly shorter operating time (WMD - 19.85; 95% CI - 38.03 to - 1.68; P = 0.03); longer recovery time of intestinal function (SMD 0.46; 95% CI 0.08 to 0.84; P = 0.02). However, the terms of estimated blood loss (WMD - 5.72; 95% CI - 19.6 to - 8.15; P = 0.42); length of stay (WMD - 0.35; 95% CI - 1.61 to 0.91; P = 0.59), visual analog pain scale (WMD - 0.38; 95% CI - 0.99 to 0.84; P = 0.22); drainage duration (WMD - 0.22; 95% CI - 0.61 to 0.17; P = 0.26); overall complication rates (OR 1.24; 95% CI 0.58 to 2.63; P = 0.58); local recurrence rate (OR 0.6; 95% CI 0.3 to 1.21; P = 0.16); distant metastasis (OR 0.94; 95% CI 0.04 to 20.77; P = 0.97); 1-year overall survival (OS) (OR 0.45; 95% CI 0.1 to 2.01; P = 0.3) showed no difference between TLNU and RLUN.

CONCLUSION

TLNU provides similar surgical outcomes and oncologic results compared to RLUN; however, TLNU has a shorter procedure time and prolonged intestinal function recovery time. Due to the heterogeneity among the studies, randomized clinical trials with follow-ups in the long term are required to obtain more definite results.

TRIAL REGISTRATION

www.crd.york.ac.uk/prospero/ , identifier CRD42023388554.

The impact of low-pressure pneumoperitoneum on robotic-assisted radical cystectomy and intracorporeal ileal conduit urinary diversion: a case-control study

Purpose

To evaluate the role of low intra-abdominal pressure (IAP) in improving postoperative recovery in Robotic-assisted radical cystectomy (RARC) and intracorporeal ileal conduit urinary diversion (ICUD).

Methods

A retrospective case–control study of 49 bladder cancer patients offered RARC/ICUD with standard (12 mmHg, n = 24) or low IAP (8 mmHg, n = 25). Outcomes of interest included length of procedure (LoP), estimated blood loss (EBL), blood transfusion, margin positivity rates, time to first flatus (TtFF), time to first bowel movement (TtFBM), ileus and small bowel obstruction (SBO) rates, time to safe discharge (TtSD), postoperative hospital stay (PHS) and pain levels on a postoperative day (POD) 1 and 3. Perioperative complications were recorded using the Clavien-Dindo system.

Results

Demographic and baseline clinical characteristics, LoP, EBL and margin positivity rates were similar between groups. No transfusions were recorded. Median (IQR) TtFF, TtFBM and TtSD were significantly longer in Group 1 vs Group 2 (4 (1) vs 2 (1), 7 (3) vs 6 (2) and 8.5 (5.75) vs 5.0 (1), respectively). PHS and rates of postoperative ileus and SBO were lower in Group 2, however not statistically significant. Severe pain was uncommon in both groups but moderate/severe pain was significantly higher in Group 1 (95.8% vs 48% on POD1 and 62.5% vs 16% on POD3). No significant intraoperative complications were recorded and ≥ Grade 3 postoperative complications at 30 and 90 days were similar.

Conclusion

With limitations, Low-IAP RARC can be safely offered to RARC/ICUD patients and leads to faster bowel recovery, and shorter time to safe discharge compared to standard pneumoperitoneum.