The impact of intra-abdominal pressure on perioperative outcomes in laparoscopic cholecystectomy: a systematic review and network meta-analysis of randomized controlled trials

Underneath Images and Robots, Looking Deeper into the Pneumoperitoneum: A Narrative Review

Laparoscopy offers numerous advantages over open procedures, minimizing trauma, reducing pain, accelerating recovery, and shortening hospital stays. Despite other technical advancements, pneumoperitoneum insufflation has received little attention, barely evolving since its inception. We explore the impact of pneumoperitoneum on patient outcomes and advocate for a minimally invasive approach that prioritizes peritoneal homeostasis. The nonlinear relationship between intra-abdominal pressure (IAP) and intra-abdominal volume (IAV) is discussed, emphasizing IAP titration to balance physiological effects and surgical workspace. Maintaining IAP below 10 mmHg is generally recommended, but factors such as patient positioning and surgical complexity must be considered. The depth of neuromuscular blockade (NMB) is explored as another variable affecting laparoscopic conditions. While deep NMB appears favorable for surgical stillness, achieving a balance between IAP and NMB depth is crucial. Temperature and humidity management during pneumoperitoneum are crucial for patient safety and optical field quality. Despite the debate over the significance of temperature drop, humidification and the warming of insufflated gas offer benefits in peritoneal homeostasis and visual clarity. In conclusion, there is potential for a paradigm shift in pneumoperitoneum management, with dynamic IAP adjustments and careful control of insufflated gas temperature and humidity to preserve peritoneal homeostasis and improve patient outcomes in minimally invasive surgery.

Best Evidence for Each Surgical Step in Minimally Invasive Right Hemicolectomy: A Systematic Review

Objective

The aim of this study was to systematically review the literature for each surgical step of the minimally invasive right hemicolectomy (MIRH) for non-locally advanced colon cancer, to define the most optimal procedure with the highest level of evidence.

Background

High variability exists in the way MIRH is performed between surgeons and hospitals, which could affect patients' postoperative and oncological outcomes.

Methods

A systematic search using PubMed was performed to first identify systematic reviews and meta-analyses, and if there were none then landmark papers and consensus statements were systematically searched for each key step of MIRH. Systematic reviews were assessed using the AMSTAR-2 tool, and selection was based on highest quality followed by year of publication.

Results

Low (less than 12 mmHg) intra-abdominal pressure (IAP) gives higher mean quality of recovery compared to standard IAP. Complete mesocolic excision (CME) is associated with lowest recurrence and highest 5-year overall survival rates, without worsening short-term outcomes. Routine D3 versus D2 lymphadenectomy showed higher LN yield, but more vascular injuries, and no difference in overall and disease-free survival. Intracorporeal anastomosis is associated with better intra- and postoperative outcomes. The Pfannenstiel incision gives the lowest chance of incisional hernias compared to all other extraction sites.

Conclusion

According to the best available evidence, the most optimal MIRH for colon cancer without clinically involved D3 nodes entails at least low IAP, CME with D2 lymphadenectomy, an intracorporeal anastomosis and specimen extraction through a Pfannenstiel incision.

Abdominal compartment syndrome in critically ill patients

Intra-abdominal hypertension can have severe consequences, including abdominal compartment syndrome, which can contribute to multi-organ failure. An increase in intra-abdominal hypertension is influenced by factors such as diminished abdominal wall compliance, increased intraluminal content, and certain systemic conditions. Regular measurement of intra-abdominal pressure is essential, and particular attention must be paid to patient positioning. Nonsurgical treatments, such as decompression of intraluminal content using a nasogastric tube, percutaneous drainage, and fluid balance optimization, play crucial roles. Additionally, point-of-care ultrasonography aids in the diagnosis and treatment of intra-abdominal hypertension. Emphasizing the importance of regular measurements, timely decompressive laparotomy is a definitive, but complex, treatment option. Balancing the urgency of surgical intervention against potential postoperative complications is challenging.

Low-Impact Laparoscopy vs Conventional Laparoscopy for Appendectomy: A Prospective Randomized Trial

BACKGROUND

Low-impact laparoscopy (LIL), combining low-pressure insufflation and microlaparoscopy, is a surgical technique that is still not widely used and that has never been evaluated for the management of acute appendicitis. The aim of this study is to assess the feasibility of an LIL protocol, to compare postoperative pain, average length of stay, and in-hospital use of analgesics by patients who underwent appendectomy according to a conventional laparoscopy or an LIL protocol.

STUDY DESIGN

Patients presenting with acute uncomplicated appendicitis who were operated on between January 1, 2021, and July 10, 2022, were included in this double-blind, single-center, prospective study. They were preoperatively randomly assigned to a group undergoing conventional laparoscopy, ie with an insufflation pressure of 12 mmHg and conventional instrumentation, and an LIL group, with an insufflation pressure of 7 mmHg and microlaparoscopic instrumentation.

RESULTS

Fifty patients were included in this study, 24 in the LIL group and 26 in the conventional group. There were no statistically significant differences between the 2 patient groups, including weight and surgical history. The postoperative complication rate was comparable between the 2 groups (p = 0.81). Pain was reported as significantly lower according to the visual analog scale 2 hours after surgery among the LIL group (p = 0.019). For patients who underwent surgery according to the LIL protocol, the study confirms a statistically significant difference for theoretical and actual length of stay, ie -0.77 days and -0.59 days, respectively (p < 0.001 and p = 0.03). In-hospital use of analgesics was comparable between both groups.

CONCLUSIONS

In uncomplicated acute appendicitis, the LIL protocol could reduce postoperative pain and average length of stay compared to conventional laparoscopic appendectomy.

Low intra-abdominal pressure in laparoscopic surgery: a systematic review and meta-analysis

BACKGROUND

Guidelines do not provide clear recommendations with regard to the use of low intra-abdominal pressure (IAP) during laparoscopic surgery. The aim of this meta-analysis is to assess the influence of low versus standard IAP during laparoscopic surgery on the key-outcomes in perioperative medicine as defined by the StEP-COMPAC consensus group.

MATERIALS AND METHODS

We searched the Cochrane Library, PubMed, and EMBASE for randomized controlled trials comparing low IAP (<10 mmHg) with standard IAP (10 mmHg or higher) during laparoscopic surgery without time, language, or blinding restrictions. According to the PRISMA guidelines, two review authors independently identified trials and extracted data. Risk ratio (RR), and mean difference (MD), with 95% CIs were calculated using random-effects models with RevMan5. Main outcomes were based on StEP-COMPAC recommendations, and included postoperative complications, postoperative pain, postoperative nausea and vomiting (PONV) scores, and length of hospital stay.

RESULTS

Eighty-five studies in a wide range of laparoscopic procedures (7349 patients) were included in this meta-analysis. The available evidence indicates that the use of low IAP (<10 mmHg) leads to a lower incidence of mild (Clavien-Dindo grade 1-2) postoperative complications (RR=0.68, 95% CI: 0.53-0.86), lower pain scores (MD=-0.68, 95% CI: -0.82 to 0.54) and PONV incidence (RR=0.67, 95% CI: 0.51-0.88), and a reduced length of hospital stay (MD=-0.29, 95% CI: -0.46 to 0.11). Low IAP did not increase the risk of intraoperative complications (RR=1.15, 95% CI: 0.77-1.73).

CONCLUSIONS

Given the established safety and the reduced incidence of mild postoperative complications, lower pain scores, reduced incidence of PONV, and shorter length of stay, the available evidence supports a moderate to strong recommendation (1a level of evidence) in favor of low IAP during laparoscopic surgery.

Relationship between ANI and qNOX and between MAC and qCON during outpatient laparoscopic cholecystectomy using remifentanil and desflurane without muscle relaxants: a prospective observational preliminary study

This study was designed to investigate qCON and qNOX variations during outpatient laparoscopic cholecystectomy using remifentanil and desflurane without muscle relaxants and compare these indices with ANI and MAC. Adult patients undergoing outpatient laparoscopic cholecystectomy were included in this prospective observational study. Maintenance of anesthesia was performed using remifentanil targeted to ANI 50-80 and desflurane targeted to MAC 0.8-1.2 without muscle relaxants. The ANI, qCON and qNOX and desflurane MAC values were collected at different time-points and analyzed using repeated measures ANOVA. The relationship between ANI and qNOX and between qCON and MAC were analyzed by linear regression. The ANI was comprised between 50 and 80 during maintenance of anesthesia. Higher values of qNOX and qCON were observed at induction and extubation than during all other time-points where they were comprised between 40 and 60. A poor but significant negative linear relationship (r² = 0.07, p < 0.001) was observed between ANI and qNOX. There also was a negative linear relationship between qCON and MAC (r² = 0.48, p < 0.001) and between qNOX and remifentanil infusion rate (r² = 0.13, p < 0.001). The linear mixed-effect regression correlation (r²) was 0.65 for ANI-qNOX and 0.96 for qCON-MAC. The qCON and qNOX monitoring seems informative during general anesthesia using desflurane and remifentanil without muscle relaxants in patients undergoing ambulatory laparoscopic cholecystectomy. While qCON correlated with MAC, the correlation of overall qCON and ANI was poor but significant. Additionally, the qNOX weakly correlated with the remifentanil infusion rate. This observational study suggests that the proposed ranges of 40-60 for both indexes may correspond to adequate levels of hypnosis and analgesia during general anesthesia, although this should be confirmed by further research.

Robotic single-site cholecystectomy is better in reducing postoperative pain than single-incision and conventional multiport laparoscopic cholecystectomy

BACKGROUND

To compare the short-term outcomes of robotic single-site cholecystectomy (RSSC) with single-incision laparoscopic cholecystectomy (SILC) and conventional multiport laparoscopic cholecystectomy (CMLC), focusing on postoperative pain outcomes.

METHODS

This single-center retrospective study included consecutive patients with benign gallbladder disease who underwent cholecystectomy by a single surgeon between June 2019 and December 2021. Exclusion criteria were acute cholecystitis (AC) and other combined surgeries. One-to-one propensity score matching was performed between the RSSC and SILC or CMLC.

RESULTS

Of the 157 patients included, 39 (24.8%) underwent RSSC, 32 (20.4%) underwent SILC, and 86 (54.8%) underwent CMLC. In a propensity score-matched cohort between RSSC and SILC (32 patients in each group), the number of additional analgesic injections was significantly lower in the RSSC group than in the SILC group (0.7 vs. 1.3, p = 0.002), and postoperative pain scores were also significantly lower at 6 h (2.8 vs. 3.6, p = 0.004) and 24 h (2.6 vs. 3.3, p = 0.021) after surgery in the RSSC group than in the SILC group. In a propensity score-matched cohort between RSSC and CMLC (23 patients in each group), the number of additional analgesic injections was significantly lower in the RSSC group than in the CMLC group (0.7 vs. 1.3, p = 0.005), and postoperative pain scores were also significantly lower at 6 h after surgery (2.9 vs. 3.7, p = 0.025) in the RSSC group than in the CMLC group.

CONCLUSION

This study demonstrated that RSSC is helpful in reducing postoperative pain and the use of additional analgesics compared to both SILC and CMLC.

Low Intra-Abdominal Pressure with Complete Neuromuscular Blockage Reduces Post-Operative Complications in Major Laparoscopic Urologic Surgery: A before-after Study

Most urological interventions are now performed with minimally invasive surgery techniques such as laparoscopic surgery. Combining ERAS protocols with minimally invasive surgery techniques may be the best option to reduce hospital length-of-stay and post-operative complications. We designed this study to test the hypothesis that using low intra-abdominal pressures (IAP) during laparoscopy may reduce post-operative complications, especially those related to reduced intra-operative splanchnic perfusion or increased splanchnic congestion. We applied a complete neuromuscular blockade (NMB) to maintain an optimal space and surgical view. We compared 115 patients treated with standard IAP and moderate NMB with 148 patients treated with low IAP and complete NMB undergoing major urologic surgery. Low IAP in combination with complete NMB was associated with fewer total post-operative complications than standard IAP with moderate NMB (22.3% vs. 41.2%, p < 0.001), with a reduction in all medical post-operative complications (17 vs. 34, p < 0.001). The post-operative complications mostly reduced were acute kidney injury (15.5% vs. 30.4%, p = 0.004), anemia (6.8% vs. 16.5%, p = 0.049) and reoperation (2% vs. 7.8%, p = 0.035). The intra-operative management of laparoscopic interventions for major urologic surgeries with low IAP and complete NMB is feasible without hindering surgical conditions and might reduce most medical post-operative complications.

Ultrasound-guided quadratus lumborum block provided more effective analgesia for children undergoing lower abdominal laparoscopic surgery: a randomized clinical trial

BACKGROUND

Postoperative pain treatment for pediatrics is often inadequate and the evidence of pediatric postoperative analgesia is scarce. To our knowledge, no report regarding the comparison among caudal block, transversus abdominis plane (TAP) block and quadratus lumborum (QL) block for children undergoing lower abdominal laparoscopic surgery was found at present. Thus this trial aimed to compare the efficacies of them for children undergoing lower abdominal laparoscopic surgery.

METHODS

One hundred and eighty children aged from 1 to 12 years undergoing lower abdominal laparoscopic surgery were included and randomized to receive caudal block, TAP block or QL block. The primary outcome was the Face, Legs, Activity, Cry, and Consolability (FLACC) score at 30 min, 1 h, 4 h, 8 h, 12 h, and 24 h and tramadol consumption during first 24 h postoperatively. Secondary outcomes included the number of children received tramadol, time to first tramadol request, parents' satisfaction and postoperative adverse reactions.

RESULTS

The QLB group had lower postoperative FLACC scores at 8 h (median difference - 0.43, P = 0.03) than the Caudal group and at 4 h (median difference - 0.6, P = 0.001) and 8 h (median difference - 0.43, P = 0.03) than the TAPB group. The tramadol consumption was lower in the QLB group (28.43 ± 6.55) than the TAPB group (37.17 ± 6.12, P = 0.023). Although the number of children received tramadol did not differ among the three groups, the time to first tramadol request was longer in the QLB group (7.20 ± 0.79) than the caudal group (8.42 ± 0.61, P = 0.008). No statistical difference was observed concerning other secondary outcomes.

CONCLUSIONS

QLB produced more effective postoperative analgesia for children undergoing laparoscopic abdominal surgery compared with the TAPB and caudal block.

The Impact of intra-abdominal Pressure on Perioperative Outcomes in Robotic-Assisted Radical Prostatectomy: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

Objective. The aim of the study is to analyze the impact of intra-abdominal pressure (IAP) on perioperative outcomes in robotic-assisted radical prostatectomy (RARP). Methods. We searched the PubMed, Cochrane Library, Science, Embase, and CNKI databases systematically, and the retrieval date was from the inception of the databases to April 2022. Randomized controlled trials on high intraabdominal pressure (HIAP) and low intraabdominal pressure (LIAP) in RARP were included. The meta-analysis was performed using Review Manager software (version 5.3). Results. Six studies involving 2,271 patients were included in the meta-analysis. Compared with patients who experienced HIAP, those who experienced LIAP had a lower incidence of postoperative ileus (POI) (risk ratio (RR): 0.42; 95% confidence interval (CI): 0.24 to 0.72; $p=0.002$ ). However, there were no significant differences in hematoma (RR 2.22; 95% CI, 0.61 to 8.15; $p=0.23$ ), positive margin rate (RR, 1.06; 95% CI, 0.84 to 1.32; $p=0.64$ ), urinary retention (RR, 0.99; 95% CI, 0.51 to 1.94; $p=0.98$ ), operative time (mean difference (MD), −0.36; 95% CI, −12.24 to 6.12; $p=0.51$ ), or intraoperative blood loss (MD, −21.80; 95% CI, −55.28 to 11.68; $p=0.20$ ) among patients undergoing LIAP and HIAP. Conclusion. Our study of published trials indicates that using LIAP during RARP may reduce the incidence of POI, and there were no differences in terms of hematoma, positive margin rate, urinary retention, operative time, or intraoperative blood loss.

The first international Delphi consensus statement on Laparoscopic Gastrointestinal surgery

BACKGROUND

Laparoscopic surgery has almost replaced open surgery in many areas of Gastro-Intestinal (GI) surgery. There is currently no published expert consensus statement on the principles of laparoscopic GI surgery. This may have affected the training of new surgeons. This exercise aimed to achieve an expert consensus on important principles of laparoscopic GI surgery.

METHODS

A committee of 38 international experts in laparoscopic GI surgery proposed and voted on 149 statements in two rounds following a strict modified Delphi protocol.

RESULTS

A consensus was achieved on 133 statements after two rounds of voting. All experts agreed on tailoring the first port site to the patient, whereas 84.2% advised avoiding the umbilical area for pneumoperitoneum in patients who had a prior midline laparotomy. Moreover, 86.8% agreed on closing all 15 mm ports irrespective of the patient's body mass index. There was a 100% consensus on using cartridges of appropriate height for stapling, checking the doughnuts after using circular staplers, and keeping the vibrating blade of the ultrasonic energy device in view and away from vascular structures. An 84.2% advised avoiding drain insertion through a ≥10 mm port site as it increases the risk of port-site hernia. There was 94.7% consensus on adding laparoscopic retrieval bags to the operating count and ensuring any surgical specimen left inside for later removal is added to the operating count.

CONCLUSION

Thirty-eight experts achieved a consensus on 133 statements concerning various aspects of laparoscopic GI Surgery. Increased awareness of these could facilitate training and improve patient outcomes.

Postprocedural Gastrointestinal Emergencies

Postprocedural complications encompass a wide array of conditions that vary in acuity, symptoms, index procedure, and treatment. Continued advancements in diagnostic and therapeutic procedures have led to a significant shift of procedures to the ambulatory setting. This trend is of particular interest to the emergency physician, as patients who develop complications often present to an emergency department for evaluation and treatment. Here the authors examine a high-yield collection of procedures, both ambulatory and inpatient, notable for their frequent utilization and unique complication profiles including common laparoscopic surgical procedures, bariatric surgery, endoscopic procedures, interventional radiology procedures, and hernia repairs with implantable mesh.

The Impact of Incentive Spirometry on Shoulder Tip Pain in Laparoscopic Cholecystectomy: A Randomized Clinical Trial

BACKGROUND

Shoulder pain is among the early postlaparoscopic symptoms related to carbon dioxide used for pneumoperitoneum, which remains in the abdominal cavity. Therefore, incentive spirometry (IS) is a novel technique to alleviate this pain following laparoscopic cholecystectomy (LC). The present study was designed to investigate if the use of IS after LC would relieve shoulder tip pain, and determine the amount of postoperative opioid analgesics utilized.

MATERIALS AND METHODS

This randomized clinical trial was conducted on patients who were clinically diagnosed with cholecystitis, and underwent LC. Accordingly, group I patients (n=42) received IS (including 10 deep breaths with a spirometer in sitting or semisitting positions) in full consciousness every 2 hours starting at 2 hours after surgery, but group II patients (n=42) did not have respiratory physiotherapy. The postoperative shoulder pain after the surgery was further evaluated by a numerical rating scale (NRS).

RESULTS

At 4, 8, 12, 24, and 48 hours following LC, the NRS pain scores significantly reduced in group I compared with group II. In addition, the results of the repeated measures analysis of variance indicated significantly lower NRS pain scores within the first 48 hours after LC in group I compared with group II. Consequently, the study findings showed a significantly higher percentage of cases in group II, requiring postoperative analgesics, in comparison with group I.

CONCLUSIONS

IS decreased the severity of shoulder tip pain after LC with no complications. Thus, IS may be considered as a viable alternative to other laparoscopic interventions. However, still further studies are necessary to evaluate its efficacy compared with other techniques.

Intraoperative Measures to Reduce the Risk of COVID-19 Transmission During Minimally Invasive Procedures: A Systematic Review and Critical Appraisal of Societies' Recommendations

BACKGROUND

The coronavirus 2019 pandemic and the hypothetical risk of virus transmission through aerosolized CO2 or surgical smoke produced during minimally invasive surgery (MIS) procedures have prompted societies to issue recommendations on measures to reduce this risk. The aim of this systematic review is to identify, summarize and critically appraise recommendations from surgical societies on intraoperative measures to reduce the risk of severe acute respiratory syndrome coronavirus 2 transmission to the operative room (OR) staff during MIS.

METHODS

Medline, Embase, and Google Scholar databases were searched using a search strategy or free terms. The search was supplemented with searches of additional relevant records on coronavirus 2019 resource websites from Surgical Associations and Societies. Recommendations published by surgical societies that reported on the intraoperative methods to reduce the risk of severe acute respiratory syndrome coronavirus 2 transmission to the OR staff during MIS were also reviewed for inclusion. Expert opinion articles were excluded. A preliminary synthesis was performed of the extracted data to categorize and itemize the different types of recommendations. The results were then summarized in a narrative synthesis.

RESULTS

Thirty-three recommendation were included in the study. Most recommendations were targeted to general surgery (13) and gynecology (8). Areas covered by the documents were recommendations on performance of laparoscopic/robotic surgery versus open approach (28 documents), selection of surgical staff (13), management of pneumoperitoneum (33), use of energy devices (20), and management of surgical smoke and pneumoperitoneum desufflation (33) with varying degree of consensus on the specific recommendations among the documents.

CONCLUSIONS

While some of the early recommendations advised against the use of MIS, they were not strictly based on the available scientific evidence. After further consideration of the literature and of the well-known benefits of laparoscopy to the patient, later recommendations shifted to encouraging the use of MIS as long as adequate precautions could be taken to protect the safety of the OR staff. The release and implementation of recommendations should be based on evidence-based practices that allows health care systems to provide safe surgical and medical assistance.

Can We Routinely Employ the Use of Low-Pressure Gynaecological Laparoscopy? A Systematic Review

Clinicians have learnt valuable lessons throughout the COV-SARS-2 pandemic, many of which have produced solutions that we aim to continue to implement within the foreseeable future. Optimising patients’ surgical pathways to reduce the length of stay and complications is an area of particular importance, both for maximal utilisation of available resources and for reduction of the exposure of inpatient and elective patients to an increased risk of infection within healthcare facilities.

The aim of this review was to investigate the possible implications of using low-pressure laparoscopic gynaecological surgery versus standard- or high-pressure pneumoperitoneum surgeries. The primary outcome was postoperative pain, with secondary outcomes including duration of surgery, length of inpatient stay and rate of complications.

MEDLINE, Embase and Cochrane CENTRAL were searched from inception to December 2020. We searched for published randomised control trials comparing low-pressure laparoscopic surgery (≤8 mmHg) to at least one additional standardised pneumoperitoneum pressure (≥12 mmHg and/or ≥15 mmHg). A total of 203 studies were reviewed, five of which were included in this analysis. Studies comparing low-pressure laparoscopic surgery against gasless abdominal cavities were excluded.

The meta-analysis of the results was pooled and calculated within RevMan 5.0 software (Cochrane, London, England). Studies using a visual analogue scale (1-10) to compare low versus standard pneumoperitoneum pressures did not display a significant diminution of postoperative pain at ≤ 6 or 24 hours: -0.30 [95% CI -0.63, 0.03] and -0.66 [95% CI -1.35, 0.02], respectively. Studies additionally demonstrated worse visualisation of the surgical field within the low-pressure group (risk ratio 10.31; 95% CI, 1.29-82.38 I² = 0%). Studies measuring postoperative pain using a numerical rating scale displayed significant pain reduction at all hours measured (p ≤ 0.01). The rate of intraoperative complications was 1% for all groups measured. Cumulative analysis of the duration of surgery did not differ significantly between groups (p = 0.99).

The pandemic has revealed new issues that must be addressed by clinicians to promote the safety of patients and the efficiency of inpatient stay. This review has paved the way for new possibilities and innovative approaches to address the issue of optimising patient surgical pathways; however, at present, we cannot give a firm justification for the use of low-pressure gynaecological laparoscopy. Reasons for this include the minimal reduction in pain scores between low, standard and high pneumoperitoneum pressures, leading to a mixture of statistically significant results, as well as a reduction in the visualisation of the surgical field and the small population sizes in the reviewed papers. Additional research is required to further explore the potential clinical benefits of gynaecological laparoscopy to ensure its effective ambulatory use within mainstream surgical operations.

The "Dark Side" of Pneumoperitoneum and Laparoscopy

Laparoscopic surgery has been one of the most common procedures for abdominal surgery at pediatric age during the last few decades as it has several advantages compared to laparotomy, such as shorter hospital stays, less pain, and better cosmetic results. However, it is associated with both local and systemic modifications. Recent evidence demonstrated that carbon dioxide pneumoperitoneum might be modulated in terms of pressure, duration, temperature, and humidity to mitigate and modulate these changes. The aim of this study is to review the current knowledge about animal and human models investigating pneumoperitoneum-related biological and histological impairment. In particular, pneumoperitoneum is associated with local and systemic inflammation, acidosis, oxidative stress, mesothelium lining abnormalities, and adhesion development. Animal studies reported that an increase in pressure and time and a decrease in humidity and temperature might enhance the rate of comorbidities. However, to date, few studies were conducted on humans; therefore, this research field should be further investigated to confirm in experimental models and humans how to improve laparoscopic procedures in the spirit of minimally invasive surgeries.

Comparison of the Safety and Efficacy of Valveless and Standard Insufflation During Robotic Partial Nephrectomy: A Prospective, Randomized, Multi-institutional Trial

OBJECTIVE

To use a randomized, prospective, multi-institutional study to compare the safety and efficacy of conventional insufflation (CIS) and valveless insufflation (AirSeal Insufflation - AIS) at the conventional pressure of 15 mm Hg in robot-assisted partial nephrectomy - a surgery where AIS has gained popularity for maintaining visualization despite suction. This study was also powered to evaluate the effect of decreasing pneumoperitoneum by 20% in the valveless system.

MATERIALS AND METHODS

Three high-volume institutions randomized subjects into CIS 15, AIS 15, and AIS 12 mm Hg cohorts. Endpoints included rates of subcutaneous emphysema (SCE), pneumothorax (PTX), pneumomediastinum (PMS), intraoperative end-tidal carbon dioxide (ET CO₂), and peak airway pressure (PAP), as well as hospital stay, post-operative pain, and complications. Given the substantial proportion of retroperitoneal surgery, a secondary analysis evaluated the effect of surgical approach.

RESULTS

Two hundred and two patients were accrued. SCE was decreased in the AIS 12 mm Hg group (p=0.003). PTX and PMS rates were not statistically significantly different across the 3 insufflation groups. Higher rates of SCE and PMS, although not PTX, were noted in all retroperitoneal surgery groups - with lower SCE rates for AIS 12 mm Hg regardless of surgical approach.

CONCLUSION

AIS is often preferred for complex procedures including retroperitoneal and transperitoneal robotic-assisted partial nephrectomy, for its maintenance of pneumoperitoneum despite continuous suction necessary for visualization. This study shows that AIS is safe when compared to CIS at 15 mm Hg, and shows improvement in outcomes when pneumoperitoneum pressure is reduced by 20% to 12 mmHg.

Analgesic efficacy of pre-emptive local wound infiltration plus laparoscopic-assisted transversus abdominis plane block versus wound infiltration in patients undergoing laparoscopic colorectal resection: results from a randomized, multicenter, single-blind, non-inferiority trial

BACKGROUND

Transversus abdominis plane (TAP) block is considered a reliable locoregional technique for pain control after laparoscopic colorectal surgery. However, no clear benefit of TAP block over wound infiltration has been demonstrated by the current literature. This multicenter randomized clinical trial tested the non-inferiority of wound infiltration (WI) compared to WI plus laparoscopic-assisted TAP block (L-TAP).

METHODS

All patients with colorectal cancer and diverticular disease scheduled for laparoscopic resection at the Division of General and Hepatobiliary Surgery, University of Verona Hospital Trust, Verona, Italy and at the Colorectal Cancer Center, Kyungpook National University Medical Center, Kyungpook National University, Daegu, Korea, between April 2018 and March 2019 were considered for the trial. Patients were randomly allocated to either the WI group or the WI plus L-TAP group in a 1:1 allocation ratio. In total, 108 patients entered the study and 102 patients were analyzed; 50 patients received WI plus L-TAP and 52 patients received WI. The primary end point was the efficacy in pain control at 6 h measured according to Numeric Rating Scale (NRS). Secondary aims evaluated pain control at 12, 24, 48 and 72 h and other short-term results related to pain management.

RESULTS

Estimation of pain intensity at 6 h was comparable between the two groups (p = 0.16) with a mean (95% CI) difference in pain scores of 0.94 (- 0.13 to 2.02). No differences in pain scores were observed at other interval times or considering analgesic consumption, return of bowel function, postoperative complications and length of hospital stay.

CONCLUSION

This study suggests that adding TAP block to WI does not affect pain control, amount of analgesics and other short-term outcomes.

TRIAL REGISTRATION

NCT03376048 ( https://www.clinicaltrials.gov ).

Efficacy and Safety of a Surgeon-Performed Laparoscopic-Guided, 4-point Transversus Abdominis Plane Block: A retrospective review

We performed a retrospective chart review from October 2017 to March 2019 to demonstrate the safety and efficacy of a surgeon-performed, laparoscopically guided, transversus abdominis plane (TAP) blocks for robot-assisted gynecologic procedures. A total of 116 patients who underwent robot-assisted gynecologic surgery, at 1 academic hospital, with administration of a 4-point TAP block were included. A 4-point TAP block was performed under laparoscopic visualization, by the same surgeon, after induction of anesthesia and immediately after placement of the laparoscope. Liposomal bupivacaine (20 mL) and 0.5% bupivacaine (20 mL) mixed with saline were used as the injectant. All information from the surgical admission and the postoperative follow-up were reviewed. Data were presented in our descriptive study. A total of 116 patients were included with a mean age of 40.6 years (19-80 years) and a mean body mass index of 30.6 kg/m² (17.2-53.3 kg/m²). Of the patients, 70.7% were discharged to home on the day of surgery. Of the 29.3% of patients who were admitted, 20.6% were admitted because of pain control. Those who were admitted for pain control comprised 6.0% of the total of all study participants. There were no adverse events in our cohort and no readmissions because of pain control. A surgeon-performed TAP block, under laparoscopic visualization, is a safe and efficacious intervention to reduce postoperative pain and may add to a multimodal approach for enhanced recovery protocols.