CO2 Insufflation Research Articles

S175 Water Exchange Increased Advanced Adenoma Detection in the Ascending and Proximal Colon As Compared to Air Insufflation

Introduction: Randomized control trials (RCT) showed significant increase in adenoma detection rate (ADR) with water exchange (WE) compared with usual air or CO2 insufflation colonoscopy. Advanced adenoma detection rate (AADR) is a validated surrogate marker for colorectal cancer risk (GI Endosc Clin N Am 2002;12:1). There was limited data of the impact of WE on AADR, probably due to the small sample sizes of RCT. Pooled analysis of 6 published RCT suggested that WE significantly increased overall ADR and overall AADR of the entire colon (JCG 2020;54:212). The impact of WE on ADR and AADR in the ascending colon, where interval cancers tend to cluster (AJG 2014;109:1375), is unknown. We test the hypothesis that WE increased AADR by aggregating the data of 4 RCTs conducted by our group in Chiayi and Hualien, Taiwan. Methods: Data from 4 RCTs (NCT01894191, NCT02737514, NCT01535326, and NCT01699399) comparing WE and air insufflation were aggregated. The demographic characteristics, procedure related outcomes, ADR and AADR were tabulated. Results: Both the WE and air insufflation group included 503 patients. Table 1 shows that the demographic characteristics were similar between the two groups. WE had significantly shorter withdrawal time [mean (SD), 13.0 (6.8) vs 12.6 (8.5), P=0.017], and higher Boston Bowel Preparation Scale scores than the air insufflation group. The ratio of aspirate water volume to infused water volume at cecum (107%) indicated proper implementation of WE (Table 1). The WE group had significantly higher overall ADR (46.4% vs 54.9%, P=0.008), with the difference mainly occurring in the ascending colon (23.0% vs 30.9%, P=0.005) than the air insufflation group. The WE group had significantly higher AADR in the ascending (4.6% vs 7.8%, P=0.048) and proximal (6.4% vs 10.5%, P=0.023) colon. The overall AADR (16.3% vs 19.7%) was numerically higher in the WE group (P=0.189, possibly a type II error) (Table 1). Conclusion: Interval cancers tend to occur in the right and proximal colon. The beneficial effect for WE to increase right and proximal colon AADR (a validated surrogate marker for colorectal cancer risk) might hold the potential to reduce the occurrence of interval cancers. The aggregated data of 4 RCTs showed WE had significantly higher AADR in the right colon and proximal colon as compared to air insufflation. Future studies to evaluate the impact of WE on the occurrence of interval cancers are justified.Table 1.: †Chi-square test; ††Fisher’s exact test; *Mann-Whitney test; ADR, adenoma detection rate; AADR, advanced adenoma detection rate; BBPS, Boston Bowel Preparation Scale. Advanced adenoma was defined as an adenoma with a diameter of ≥ 10 mm, significant villous features (> 25%), or high-grade dysplasia. The ascending colon included the cecum, ascending colon and hepatic flexure. The proximal colon included the cecum, ascending and transverse colon.

Retroperitoneoscopic debridement and internal fixation for the treatment of lumbar tuberculosis.

To describe the retroperitoneoscopic debridement technique and evaluate the clinical outcome of internal fixation for the treatment of lumbar tuberculosis.Twenty-eight patients were performed conventional laparoendoscopic technique (n = 17) or laparoendoscopic single-site technique (n = 11). Antituberculosis chemotherapy and thoracolumbosacral orthosis were given to all patients. The clinical outcomes were evaluated with preoperative and postoperative Visual Analog Scale, and radiographs with respect to sagittal angle and fusion status.Average time of the 28 procedures was 220.6 ± 50.9 min (180–365 min). The average intraoperative blood loss was 108.6 ± 95.3 mL (50–400 mL). All patients showed significant improvement of their Visual Analog Scale back pain score at follow-up and were classified as having a radiographic fusion in this study. The mean sagittal angle was 11.2 ± 3.6° before operation, significantly improved to 3.7 ± 2.4° after operation. There were no recurrent infections during the follow-up period. Complications included loosening of anterior fixation and temporary deficit of the sympathetic nerve.Retroperitoneal laparoscopic approach with CO2 insufflation technique is a challenging but safe and effective procedure for lumbar spine tuberculosis. Retroperitoneal laparoendoscopic single-site can be used for anterior lumbar spine surgery, offer exposure for L1 through L5.

V08-11 SINGLE PORT SIMPLE PROSTATECTOMY

You have accessJournal of UrologyNOTES/LESS (V08)1 Sep 2021V08-11 SINGLE PORT SIMPLE PROSTATECTOMY Susan Talamini, and Simone Crivellaro Susan TalaminiSusan Talamini More articles by this author , and Simone CrivellaroSimone Crivellaro More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002041.11AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: The open simple prostatectomy has been utilized in the surgical management of benign prostatic hyperplasia (BPH) in exceedingly large glands. More recently, laparoscopic and robotic approaches have been adapted. We aim to present our approach to the transvesical robotic assisted simple prostatectomy (RASP) utilizing the daVinci Single Port robotic platform. METHODS: Our patient is an 85yo male with a long history of urinary retention, and was catheter dependent. He failed medicotherapy and was interested in definitive surgical management. The transvesical approach was facilitated using cystoscopic guidance with CO2 insufflation. A suprapubic incision, three finger breadths above the pubic bone was carried down until the bladder was encountered, and a mucosal diverticulum was created. The light from the cystoscope guides dissection. The gland was enucleated in an avascular plane, and the prostatic fossa, urethra, and bladder neck are reapproximated. RESULTS: Our experience with the first 16 cases performed at our institution reveals a significant decrease in mean postoperative IPSS (25.5 vs 6.4, p-value<0.01), post void residual(PVR) (200 vs 44.6, p-value 0.048), PSA (11 vs 0.6, p-value 0.5), and no patients developed stress urinary incontinence. One patient developed de novo urge urinary incontinence. The patient highlighted in this video was discharged on postoperative day(POD) 0, his catheter removed POD 5, and his PVR was 45ml on follow up. CONCLUSIONS: The Single Port RASP is an innovative approach to the treatment of BPH. We have found excellent functional outcomes postoperatively, with significant decrease in PVRs, and no patients developing stress urinary incontinence postoperatively, potentially owing to the minimal traction on the rhabdosphincter, judicious use of energy application, and the bladder neck reconstruction. The Single Port RASP is a viable approach to the surgical management of large gland BPH. Source of Funding: No sources of funding to declare © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e604-e604 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Susan Talamini More articles by this author Simone Crivellaro More articles by this author Expand All Advertisement Loading ...

MP22-20 QUANTIFICATION OF RESIDUAL PNEUMOPERITONEUM AFTER ROBOT-ASSISTED LAPAROSCOPIC RADICAL PROSTATECTOMY

INTRODUCTION AND OBJECTIVE:Robot-assisted laparoscopic surgery relies on CO2 insufflation to establish the operative field. Most residual CO2 is expelled prior to port and incision closure. While s...

Stapling of an endobronchial suction tube with the bronchus during robot-assisted right lower lobectomy: a case report

BackgroundTroubleshooting intraoperative complications requires careful management, and the safest technique should be chosen. We recently experienced a unique intraoperative bronchial complication during pulmonary lobectomy in robot-assisted thoracic surgery (RATS). There is no consensus on whether to continue RATS or convert to a more familiar technique, such as video-assisted thoracic surgery (VATS) or thoracotomy, for intraoperative complications that occur during RATS, and the decision should be determined individually.Case presentationA 74-year-old woman with primary lung adenocarcinoma (clinical stage IA2) underwent robot-assisted right lower lobectomy under one-lung ventilation and CO2 insufflation. Intraoperatively, the anesthesiologist placed the endobronchial suction tube in the right bronchus with intention of maintaining the right lung collapse, which was simultaneously stapled with the right lower bronchus during the right lower lobe bronchial closure using a robotic stapler. During robot-assisted manipulation, we removed the staples involved with the suction tube, one by one, using robotic-arm forceps and sutured the partially opened stump. Subsequently, the bronchial stump was covered with a pedicled pericardial fat pad. The postoperative course was uneventful, and the patient developed no complications when followed up 8 months after discharge. Hence, we could rectify this intraoperative bronchial complication using a robot-assisted technique and avoid conversion to VATS or thoracotomy.ConclusionThe precise manipulation techniques in RATS contributed to facilitate the successful execution of surgical procedures, such as staple removal and re-suturing of the bronchial stump and may be a useful as a method for such troubleshooting such intraoperative complications.

Robotic-assisted left lower-lobe pulmonary lobectomy: Eleven steps.

Robotic-assisted left lower-lobe pulmonary lobectomy: Eleven steps.

Comparison of the effects of volume-controlled ventilation and pressure-controlled ventilation modes on hemodynamics, respiratory mechanics and blood gas parameters in patients undergoing laparoscopic cholecystectomy

Background: This study aimed to compare the changes induced by VCV and PCV modes in hemodynamics, respiration (airway pressures, gas exchange parameters) and metabolism (acid-base balance) in patients undergoing laparoscopic cholecystectomy.Methods: Patients were divided into two randomised groups as volume-controlled ventilation (VCV) group (VC) and pressure-controlled ventilation (PCV) group (PC). The following parameters were recorded at 3 different time points: T1: in supine position 10 minutes after induction of anaesthesia, T2: 15 minutes after CO2 insufflation in inverted Trendelenburg position (head 30 degrees up), T3: 10 minutes after CO2 desufflation. HR, SpO2, SAP (systolic arterial pressure), DAP (diastolic arterial pressure), MAP (mean arterial pressure), PetCO2 (end-tidal carbon dioxide pressure), Ppeak, Pplateau, Pmean, Vt (tidal volume) and compliance with the available data, the cases in both groups Vd, Vd/Vt ratios and P(A-a)O2 were calculated. Arterial blood gas parameters (pH, PaO2, PaCO2, SaO2, P(a-et)CO2) values were recorded.Results: It was found that Ppeak and Pplateau values were significantly higher in the VC group (p&lt;0.05). It was found that compliance was significantly higher in the PC group (p&lt;0.05) (p&lt;0.01). In the postoperative period, it was found that PaO2 values were significantly higher in the PC group compared to the VC group (p&lt;0.05). It was found that the P(A-a)O2 values of the PC group were significantly higher than those of the VC group during the desufflation phase (p&lt;0.05).Conclusions: We think that PCV mode can be a good alternative for the prevention and correction of physiopathological changes due to laparoscopic surgery.

Anesthetic management of thoracoscopic procedures in neonates: a retrospective analysis of 45 cases.

BackgroundAdvances in medical techniques and equipment have enabled the thoracoscopic repair of certain congenital abnormalities in neonates including congenital esophageal atresia/tracheoesophageal fistula (EA/TEF) and congenital diaphragmatic hernia (CDH). A retrospective analysis was conducted to examine the anesthetic management of neonates (7 days or younger) undergoing thoracoscopic surgery in our hospital department, and to determine the efficacy of anesthetic management in neonates.MethodsClinical data from 45 neonates who underwent thoracoscopic surgery in our hospital from December 2015 to March 2020 were retrospectively analyzed. A total of 25 patients underwent repair of CDH and 20 underwent repair of an EA/TEF.ResultsAll patients received general anesthesia with endotracheal intubation, standard ASA monitoring, and arterial blood gas (ABG) analysis. All patients survived the surgery. A total of 14 patients experienced decreases in SpO2, pH, PaO2, and increases in PETCO2 and PaCO2 30 minutes after CO2 insufflation. Our anesthetic management protocols are outline and analyzed.ConclusionsThorough preoperative preparation is critical for a desirable outcome in neonates undergoing a thoracoscopic repair of CDH or EA/TEF. In our cohort, intraoperative ventilation strategies included pressure control ventilation with peak airway pressure maintained at 15–25 cmH2O, a respiratory rate of 35–55 breaths/minute, a fraction of inspired oxygen (FiO2) of 60–80%, an inspiratory/expiratory ratio (I:E) of 1:1–1.5, and careful airway suctioning to clear secretions. Postoperatively, maintaining normovolemia and hemodynamic stability are critical for successful weaning of ventilatory support and extubation.

The Usefulness of Endoscopic Harvesting of the Latissimus Dorsi Flap for Breast Reconstruction Using a Single-Port and CO2 Gas Insufflation Technique.

In the recent trend toward less aggressive approaches to breast reconstruction, minimally invasive harvesting of the latissimus dorsi (LD) flaps has long been a desirable goal. Endoscopically-assisted LD flap harvesting was reported as a method for minimizing scar formation and reducing donor-site morbidity. This study investigates the surgical outcomes of endoscopically-assisted immediate breast reconstruction with LD muscle flaps. This prospective study included 21 patients who underwent endoscopically-assisted breast reconstruction with LD muscle flap and 20 patients who underwent breast reconstruction with conventional harvesting LD musculocutaneous flap. In patients with nonexcised skin or possible primary closure, the reconstruction was performed with endoscopically-assisted LD muscle flaps using the single-port and CO2 gas insufflation technique. The patients were classified into groups according to the location of the defect and mastectomy type. Moreover, patient satisfaction was investigated 6months after surgery. In patients who underwent endoscopically-assisted breast reconstruction with LD muscle flaps, the scar of the donor-site was vertical, and the size was 4 cm to be obscured when lowering the arms. In comparison with patients who underwent breast reconstruction with conventional LD flaps, those who underwent endoscopically-assisted breast reconstruction with LD muscle flaps showed shorter hospital stay and no difference in patient satisfaction. Endoscopically-assisted breast reconstruction with LD flaps showed no difference in patient satisfaction with good esthetic results compared with conventional LD flaps. The endoscopic LD muscle flap harvest technique using a single-port and CO2 insufflation technique can be very useful in breast reconstruction that does not require a skin paddle. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Challenges in Anesthesia Management for Peroral Endoscopic Myotomy: A Retrospective Analysis.

Peroral endoscopic myotomy (POEM) is used to treat achalasia with efficacy and reliability. However, during the procedure potential complications require attention in terms of anesthesia. This study aimed to investigate complications of the POEM procedure and its effects on arterial blood gas (ABG) parameters, peak airway pressures (PIP), hemodynamics, and postoperative analgesia requirements. Data from 220 patients who underwent POEM between 2014 and 2017 were retrospectively assessed. During the procedure, ABG samples, PIP, mean arterial pressure, and heart rate were recorded. The effects of the procedure and paracentesis on ABG, PIP, mean arterial pressure, heart rate, perioperative complications, and postoperative analgesia requirements were assessed. Data from 220 POEM patients were analyzed. During the procedure, the mean PaCO2 was 48.27±6.34 mm Hg, which was significantly higher than the PaCO2 values before and after the procedure. The mean increase in maximum PIP was 5.90±3.49 cmH2O during the procedure. However, there was a significant decrease in PaCO2 and PIP values in cases with paracentesis compared with those without paracentesis. With regards to complications, subcutaneous emphysema (48, 21.8%), pneumoperitoneum requiring decompression (66, 30%), pneumothorax (1, 0.5%), aspiration pneumonia (1, 0.5%), and bronchospasm (5, 2.2%) were observed during the procedure. In the postoperative period, 58 patients (26%) had additional analgesia requirements because of visual analog scale values >3. Periprocedural abdominal decompression with veress needle led to a reduction in arterial PaCO2 and PIP, and improved postoperative analgesia. Serious complications because of perioperative aspiration and CO2 insufflation were observed during the POEM procedure.

The Effect of Transoral Endoscopic Thyroidectomy Vestibular Approach on Regional Cerebral Oxygen Saturation: A Prospective Observational Study.

Decreased regional cerebral oxygen saturation (rSO2) is associated with neurological events. We aimed to investigate the effects of carbon dioxide (CO2) insufflation applied to the neck during transoral endoscopic thyroidectomy vestibular approach (TOETVA) surgery on the rSO2. Patients scheduled for TOETVA and open thyroidectomy (OT) were enrolled between October 2019 and November 2020. Alongside hemodynamic parameters, the rSO2 values of the patients were recorded at 5 different times. These were; before anesthesia induction (T0), 10 minutes after anesthesia induction (T1), 5 minutes after the patient was placed in the operation position (T2), 10 minutes after the CO2 insufflation in the TOETVA group, 10 minutes after the platysma incision in the OT group (T3), 10 minutes after the CO2 desufflation in the TOETVA group, 10 minutes after platysma closure in the OT group (T4), at the end of the surgery (T5). A total of 40 patients, 20 in each group, were included in the study. The surgery duration was 113±26.9 minutes in the OT group, while it was 274.1±78.1 minutes in the TOETVA group (P=0.000). The EtCO2 values during the T3 time interval; group OT 31±2.2, group TOETVA 33.9±2.1 (P=0.000). The rSO2 values of the patients were similar, except for the T3 time interval. While the right rSO2 value we obtained during the T3 time interval in the TOETVA and OT groups were 66.9±9.1 and 73.9±7.8 (P=0.013), the left rSO2 value in the TOETVA and OT groups were 66.3±9.9 and 74.8±6.8 (P=0.003), respectively. As long as the patients stay within the limits of normocapnia, the CO2 insufflation applied during TOETVA surgery has no negative effects on rSO2.

The assessment of the effect of different intraabdominal pressures used for laparoscopic cholecystectomy surgery on optic nerve sheath diameter: a prospective observational cohort study

Background/aimDuring laparoscopic cholecystectomy operations, increases in intraabdominal, intrathoracic, and intracranial pressures (ICP) can be seen after pneumoperitoneum created for surgical imaging. Orbital ultrasonography (USG), which has been developed in recent years, is a method that can evaluate the ICP by measuring the optic nerve sheath diameter (ONSD) from the eyeball.In our study, we aimed to evaluate whether different intraabdominal pressure values created during laparoscopic cholecystectomy operations correlate with ICP by measuring ONSD.Materials and methodsThe study included a total of 90 patients with American Society of Anesthesiologists (ASA) physical status classification I (ASA I) and II (ASA II) and ages from 18 to 65 years with laparoscopic cholecystectomy planned.After the patients were intubated, at the 5th min, bilateral ONSD measurements were performed. The same measurements were performed at the 15th and 30th min after CO2 insufflation and additionally 10 min after CO2 was released at the end of the operation. During intrabdominal CO2 insufflation, patients with 10 mmHg pressure applied comprised Group 1, patients with 12 mmHg pressure applied comprised Group 2, and patients with 14 mmHg pressure applied comprised Group 3.Results The study was completed with 89 patients, 51 female and 38 males. One patient was excluded from the study due to erroneous values. The variations in ONSD measured in the right-left eye before pneumoperitoneum and at the 15th and 30th min after abdominal CO2 insufflation were observed to be statistically significant (p < 0.01). In all three groups, the right and left eye ONSD values were not identified to be statistically significantly different (p > 0.01).A significant increase was observed in ONSD values in direct proportion to the increase in intraabdominal pressure in patients undergoing laparoscopic cholecystectomy surgery.Conclusion USG-guided ONSD measurements appear be a guide to ensure optimization of intraabdominal pressures and safe anesthesia administration for patients, especially those at risk of ICP increase, during laparoscopic surgery.

Minimally Invasive Plication of the Diaphragm: A Single-Center Prospective Study.

Plication of the diaphragm is a life-changing procedure for patients affected by diaphragm paralysis. Traditionally, this procedure is performed through a thoracotomy. Access to the diaphragm via this incision is poor and the indications for surgery are limited to patients who can actually sustain such an invasive approach and associated morbidities. A minimally invasive approach was developed to improve the surgical management of diaphragm paralysis. Patients underwent minimally invasive diaphragm plication either by video-assisted or robotic surgery through a 3-port technique with CO2 insufflation. Patients were followed at the routine 6-week clinic and also by telephone consultation 6 to 12 months postoperatively. Data were collected on postoperative complications, postoperative pain or numbness, symptomatic improvement, and change to quality of life following surgery. Forty-eight patients underwent 49 minimally invasive diaphragm plication. Median postoperative length of hospital stay was 4 days (range: 2 to 34 days) and there were no cases of mortality. Mean reduction in Medical Research Council dyspnea score per patient was 2.2 points (mode: 3 points). Twenty-eight patients (77.8%) reported a significant symptomatic improvement enabling improvements in quality of life, and 97.2% (n = 35) were satisfied with the surgical outcome. Minimally invasive diaphragm plication is a safe procedure associated with prompt postoperative recovery. It is effective at reducing debilitating dyspnea and improving quality of life.

How to Perform a High-Quality Endoscopic Submucosal Dissection

How to Perform a High-Quality Endoscopic Submucosal Dissection

How to choose a suitable intraabdominal pressure level during single-incision laparoscopic surgery in children

Laparoscopic surgery has become a common procedure in pediatric patients. However, adverse hemodynamic changes such as the increase of intraabdominal pressure (IAP) may occur laparoscopic surgery. The aim of this study is find a method to set a suitable IAP level in children before laparoscopic surgery. From Jan 2012 to Dec 2014, data were collected from a total of 1776 children needing laparoscopic high ligation of hernia sac. A retrospective data analysis was performed using a new defined variant Index A which had information of age, body mass index (BMI) and duration of pneumoperitoneum. The blood pressures (SBP and DBP) and the PaCO2 were increased but SV showed no changes in patients after CO2 insufflation. The complications were found in 32 cases including 2 cases with subcutaneous emphysemarelated to the CO2 insufflation directly, 3 cases of respiratory infection, 5 cases of incision infection and 2 cases of urinary tract infection) and technique related. Furthermore, the risks of complications were negatively associated with the Index A. An IAP can be optimal set up in laparoscopic high ligation of hernia sac by using the Index A.

Fetal blood gases after in utero carbon dioxide insufflation for percutaneous fetoscopic spina bifida repair

Prenatal repair of open spina bifida via the percutaneous fetoscopic approach does not require maternal laparotomy, hysterotomy, or exteriorization of the uterus. This technique requires intrauterine partial CO2 insufflation. Limited data exist on the physiological effects of CO2 insufflation on human fetuses, with no data on open spina bifida repair performed using the entirely percutaneous fetoscopic surgical technique. Our aim was to examine the effects of intrauterine partial CO2 insufflation on fetal blood gases after percutaneous fetoscopic open spina bifida repair. This was a prospective study of patients who underwent percutaneous fetoscopic open spina bifida repair from February 2019 to July 2020. Fetal cordocentesis of the umbilical vein was performed in cases with favorable access to the umbilical cord. The umbilical vein cord blood samples were obtained under ultrasound guidance immediately at the conclusion of the open spina bifida repair. Simultaneous maternal arterial blood gas samples were also obtained. The results are reported as median (range). Of the 20 patients who underwent percutaneous fetoscopic open spina bifida repair during the study period, 7 patients (35%) underwent fetal blood sampling. The gestational age at the time of surgery was 27.4 (24.0-27.9) weeks and the operative time was 183 (156-251) minutes. The CO2 exposure time was 122 (57-146) minutes with maximum pressure of 13.5 (12.0-15.0) mm Hg. Fetal umbilical vein results were as follows: pH 7.35 (7.30-7.39), partial pressure of O2 56.2 (47.1-99.9) mm Hg, partial pressure of CO2 43.8 (36.2-53.0) mm Hg, HCO3 23.9 (20.1-25.6) mmol/L, and base excess -2.2 (-4.5 to -0.4) mmol/L. Simultaneous maternal arterial blood gas results were as follows: pH 7.37 (7.28-7.42), partial pressure of O2 187.5 (124.4-405.2) mm Hg, partial pressure of CO2 36.6 (30.7-46.0) mm Hg, HCO3 21.3 (18.0-22.8) mmol/L and base excess -3.2 (-5.9 to -1.8) mmol/L. Despite prolonged CO2insufflation of the uterus, fetal umbilical vein pH and base excess values did not approach those associated with potentially pathologic fetal acidemia.

Quantification of residual pneumoperitoneum after robotic-assisted laparoscopic surgery

Abstract Objective Laparoscopic surgery improves the postoperative recovery process and relies on CO2 insufflation to establish the operative field. Most residual CO2 is expelled prior to port and incision closure. Computed tomography (CT) is often used to assess an acute abdomen and is highly sensitive in detecting free intra-abdominal air – the hallmark sign of a bowel injury. Yet, the clinical significance of free air in the early postoperative period is confounded by residual CO2 and is not usually due to a visceral injury. The aim of this prospective study was to systematically quantify the residual pneumoperitoneum (RPP) at varying timepoints after robotic-assisted laparoscopic surgery. Methods Patients undergoing robot-assisted laparoscopic intervention, both radical prostatectomies and left hemicolectomies, were prospectively enrolled in the study. At the conclusion of each operation, manual abdominal pressure was applied to aid in exsufflation of residual CO2. Very-low-dose CT scans were performed on postoperative days (POD) 3, 5, and 7, with subsequent volumetric quantification of RPP. To investigate potential factors influencing the quantity of RPP, correlation plots were made against BMI, age, operative time, total insufflation volume, intra-abdominal pressure, time to flatus and first bowel movement, pain score, and postoperative analgesic requirement. Results Thirty-one patients undergoing robotic assisted laparoscopic prostatectomy were untill now enrolled in the study, of which only one experienced a Clavien-Dindo 2 complication; all others were free of any complications during post-operative assessment period. On POD3, 5, and 7, 97%, 94%, and 68% of patients, respectively, demonstrated RPP. The RPP volumes were noted to be 9.6 mL (IQR = 3.9-31.8; maximum = 247 mL) on POD3, 1.0 mL (0.1-5.1; maximum = 221 mL) on POD5, and 0.08 mL (1-1.2; maximum = 112 mL) on POD7. A significant correlation was only appreciated between RPP volume and BMI; those with higher BMIs had lower initial volumes of RPP on POD3 and exhibited a more rapid decrease in RPP over one week. Conclusion One week after robot-assisted laparoscopic operations, a majority of patients will exhibit clinically insignificant RPP, even with volumes as high as 250 mL. Larger patients tend to have smaller residuals of CO2. Our data provide new basic knowledge regarding RPP and may help to interpret postoperative CT-scans.

Dynamic Indices Fail to Predict Fluid Responsiveness in Patients Undergoing One-Lung Ventilation for Thoracoscopic Surgery.

Thoracic surgery using CO2 insufflation maintains closed-chest one-lung ventilation (OLV) that may provide the necessary heart–lung interaction for the dynamic indices to predict fluid responsiveness. We studied whether pulse pressure variation (PPV) and stroke volume variation (SVV) can predict fluid responsiveness during thoracoscopic surgery. Forty patients were enrolled in the study. OLV was performed with a tidal volume of 6 mL/kg at a positive end-expiratory pressure of 5 cm H2O, while CO2 was insufflated to the contralateral side at 8 mm Hg. Patients whose stroke volume index (SVI) increased ≥15% after fluid challenge (7 mL/kg) were defined as fluid responders. The predictive ability of PPV and SVV on fluid responsiveness was investigated using the area under the receiver-operator characteristic curve (AUROC), which was also assessed according to the right or left lateral decubitus position considering the intrathoracic location of the right-sided superior vena cava. AUROCs of PPV and SVV for predicting fluid responsiveness were 0.65 (95% confidence interval 0.47–0.83, p = 0.113) and 0.64 (95% confidence interval 0.45–0.82, p = 0.147), respectively. The AUROCs of indices did not exhibit any statistical significance according to position. Dynamic indices of preload cannot predict fluid responsiveness during one-lung ventilation with CO2 gas insufflation.

ID: 3520197 INTERIM ANALYSIS OF A MULTICENTER RANDOMIZED CONTROLLED TRIAL COMPARING THE RIGHT COLON ADENOMA AND SERRATED POLYP MISS RATES WITH COLONOSCOPY USING WATER EXCHANGE AND CARBON DIOXIDE INSUFFLATION

Missed lesions contribute to post-colonoscopy colorectal cancer (PCCRC). Single-center randomized controlled trials (RCTs) (JCG 2020 [in press]; GIE 2020;91:AB108) showed a significant reduction in right colon adenoma miss rate (rAMR) using water exchange (WE) compared to carbon dioxide (CO2) or air insufflation. Generalizability of these results awaits confirmation by a multicenter trial. We are conducting a prospective multicenter RCT to test the hypothesis that WE produces a significantly lower rAMR and right colon serrated polyp miss rate (rSPMR) than CO2 insufflation. We report a preplanned interim analysis at 50% enrollment approved by the institution review board.

Intraoperative evaluation of colorectal anastomotic integrity: a comparison of air leak and dye leak tests.

Air leak tests (ALTs) and dye leak tests (DLTs) are the most common techniques for Intraoperative colorectal anastomosis assessment. The aim of our study was to compare the sensitivity of ALT with DLT in intraoperative evaluation of colorectal anastomotic integrity and to quantify the pressures routinely used in these tests. A prospective clinical trial was conducted on patients who had elective colorectal resection and primary anastomosis from November 2017 until July 2019 in a single academic referral center. Each patient underwent both tests. The ALT was a transanal insufflation of CO2 and inspection of escaping bubbles around the anastomosis immersed in saline. The DLT was a transanal infusion of diluted methylene blue and inspection of dye stains on surgical gauze wrapping the anastomosis. Peak pressures were measured. Primary endpoints were the sensitivity of ALT and DLT in detecting intraoperative leaks, quantification of intraluminal pressure routinely used in these settings and assessment of postoperative complications such as a clinical leak. Forty patients underwent elective colorectal resection and anastomosis for malignant (67%) or benign n (33%) etiology. Height of anastomoses ranged from 1 to 25cm (mean ± SD 12 ± 6cm). Mean pressures measured were 26.5 ± 6.6mmHg for the DLT and 22 ± 4mmHg for the ALT (p < 0.01). Twenty percent of the DLTs were positive (8 patients) compared to 2.5% (1 patient) of the ALTs (RR 1.97, CI 1.2-2.7; p = 0.03). All patients who had positive tests had a suture reinforcement of the anastomosis. Only 1 patient, who had a positive DLT and ALT, developed a clinical leak CONCLUSIONS: DLT is more sensitive in detecting anastomotic leak intraoperatively. This is the first study measuring anastomotic tests' pressures used in-vivo in humans demonstrating a range of 20-30 mmHg. Based on our data we believe that a positive DLT with a negative ALT may be treated with suture reinforcement alone. NCT03316677-10/17/2017.