International assessment and validation of the prognostic role of lymph node ratio in patients with resected pancreatic head ductal adenocarcinoma.

Background: Lymph node ratio (LNR; positive/harvested lymph nodes) was identified as overall survival predictor in several cancers, including pancreatic adenocarcinoma. It remains unclear if LNR is predictive of overall survival in pancreatic adenocarcinoma patients staged pN2. This study assessed the prognostic overall survival role of LNR in pancreatic adenocarcinoma patients in relation with lymph node involvement. Methods: A retrospective international study in six different centers (Europe and United States) was performed. Pancreatic adenocarcinoma patients who underwent pancreatoduodenectomy from 2000 to 2017 were included. Patients with neoadjuvant treatment, metastases, R2 resections, or missing data regarding nodal status were excluded. Survival curves were calculated using Kaplan-Meier method and compared using log-rank test. Multivariable Cox regressions were performed to find independent overall survival predictors adjusted for potential confounders. Results: A total of 1,327 patients were included. Lymph node involvement (pN+) was found in 1,026 patients (77%), 561 pN1 (55%) and 465 pN2 (45%). Median LNR in pN+ patients was 0.214 [interquartile range (IQR): 0.105-0.364]. On multivariable analysis, LNR was the strongest overall survival predictor in the entire cohort [hazard ratio (HR) =5.5; 95% confidence interval (CI): 3.1-9.9; P<0.001] and pN+ patients (HR =3.8; 95% CI: 2.2-6.6; P<0.001). Median overall survival was better in patients with LNR <0.225 compared to patients with LNR ≥0.225 in the entire cohort and pN+ patients. Similar results were found in pN2 patients (worse overall survival when LNR ≥0.225). Conclusions: LNR appeared as an important prognostic factor in patients undergoing surgery for pancreatic adenocarcinoma and permitted to stratify overall survival in pN2 patients. LNR should be routinely used in complement to tumor-node-metastasis (TNM) stage to better predict patient prognosis.

Comparison of surgical outcomes for colostomy closure performed by acute care surgeons versus a dedicated colorectal surgery service.

BACKGROUND: Despite colostomy closure being a common procedure, it remains highly morbid. Previous literature suggests that complication rates, including surgical site infections, intra-abdominal abscess, and anastomotic failures, reach as high as 50%. With the creation of a dedicated colorectal service, colostomy reversals have been largely migrated from the acute care surgery services. This study analyzes the differences in outcomes in colostomy closures performed between colorectal surgeons and acute care surgeons. METHODS: We retrospectively analyzed our experience with 127 colostomy closures performed in our hospital system by acute care surgeons and colorectal surgeons from 2016 through 2020. Demographic data, operative data, and outcomes such as abscess formation, anastomotic leak, and readmission were analyzed. Multivariate regression analysis was performed for intraabdominal abscesses and anastomotic leaks. RESULTS: In total, 71 colostomy closures were performed by colorectal surgeons (56%) and 56 by acute care surgeons (43%). The majority of colostomy reversals were after Hartmann's procedure for perforated diverticulitis. No differences in demographics were identified, except for a shorter interval to closure in the acute care surgeons group (10.0 vs 7.2 months; P = .049). Two (3.6%) acute care surgeon patients required colorectal surgeon consultation during the definitive repair. Regression analysis identified body mass index (odds ratio 2.43; P = .001), male gender (odds ratio -2.39; P = .18), and colorectal surgeons (odds ratio -2.28; P = .025) as significant risk factors for anastomotic leak. CONCLUSION: Analysis of the current series identified female gender and increased body mass index as higher risk, while procedures performed by colorectal surgeons were at decreased risk for anastomotic leak. Our study identified colostomy reversals performed by a dedicated colorectal service decreased the rate of anastomotic leak.

Long-Term Clinical Outcomes of an Antibiotic-Coated Non-Cross-linked Porcine Acellular Dermal Graft for Abdominal Wall Reconstruction for High-Risk and Contaminated Wounds.

BACKGROUND: Abdominal wall reconstruction in high-risk and contaminated cases remains a challenging surgical dilemma. We report long-term clinical outcomes for a rifampin-/minocycline-coated acellular dermal graft (XenMatrix™ AB) in complex abdominal wall reconstruction for patients with a prior open abdomen or contaminated wounds. METHODS: Patients undergoing abdominal wall reconstruction at our institution at high risk for surgical site occurrence and reconstructed with XenMatrix™ AB with intent-to-treat between 2014 and 2017 were included. Demographics, operative characteristics, and outcomes were collected. The primary outcome was hernia recurrence. The secondary outcomes included length of stay, surgical site occurrence, readmission, morbidity, and mortality. RESULTS: Twenty-two patients underwent abdominal wall reconstruction using XenMatrix™ AB during the study period. Two patients died while inpatient from progression of their comorbid diseases and were excluded. Sixty percent of patients had an open abdomen at the time of repair. All patients were from modified Ventral Hernia Working Group class 2 or 3. There were a total of four 30-day infectious complications including superficial cellulitis/fat necrosis (15%) and one intraperitoneal abscess (5%). No patients required reoperation or graft excision. Median clinical follow-up was 38.2 months with a mean of 35.2 +/- 18.5 months. Two asymptomatic recurrences and one symptomatic recurrence were noted during this period with one planning for elective repair of an eventration. Follow-up was extended by phone interview which identified no additional recurrences at a median of 45.5 and mean of 50.5 +/-12.7 months. CONCLUSION: We present long-term outcomes for patients with high-risk and contaminated wounds who underwent abdominal wall reconstruction reinforced with XenMatrix™ AB to achieve early, permanent abdominal closure. Acceptable outcomes were noted.

Effect of Margin Status on Survival After Resection of Hilar Cholangiocarcinoma in the Modern Era of Adjuvant Therapies.

INTRODUCTION: Studies have shown that for patients with hilar cholangiocarcinoma (HC), survival is associated with negative resection margins (R0). This requires increasingly proximal resection, putting patients at higher risk for complications, which may delay chemotherapy. For patients with microscopically positive resection margins (R1), the use of modern adjuvant therapies may offset the effect of R1 resection. METHODS: Patients at our institution with HC undergoing curative-intent resection between January 2008 and July 2019 were identified by retrospective record review. Demographic data, operative details, tumor characteristics, postoperative outcomes, recurrence, survival, and follow-up were recorded. Patients with R0 margin were compared to those with R1 margin. Patients with R2 resection were excluded. RESULTS: Seventy-five patients underwent attempted resection with 34 (45.3%) cases aborted due to metastatic disease or locally advanced disease. Forty-one (54.7%) patients underwent curative-intent resection with R1 rate of 43.9%. Both groups had similar rates of adjuvant therapy (56.5% vs. 61.1%, P = .7672). Complication rates and 30 mortality were similar between groups (all P > .05). Both groups had similar median recurrence-free survival (R0 29.2 months vs. R1 27.8 months, P = .540) and median overall survival (R0 31.2 months vs. R1 38.8 months, P = .736) with similar median follow-up time (R0 29.9 months vs. R1 28.5 months, P = .8864). CONCLUSIONS: At our institution, patients undergoing hepatic resection for HC with R1 margins have similar recurrence-free and overall survival to those with R0 margins. Complications and short-term mortality were similar. This may indicate that with use of modern adjuvant therapies obtaining an R0 resection is not an absolute mandate.

Prognostic value of positive histological margins in patients with pancreatic head ductal adenocarcinoma and lymph node involvement: an international multicentric study.

BACKGROUND: Resection margin status and lymph node (LN) involvement are known prognostic factors for patients who undergo pancreatoduodenectomy for pancreatic ductal adenocarcinoma (PDAC). This study aimed to compare overall survival (OS) and disease-free survival (DFS) by resection margin status in patients with PDAC and LN involvement. METHODS: A retrospective international multicentric study was performed including four Western centers. Multivariable Cox analysis was performed to identify prognostic factors of OS and DFS. Median OS and DFS were calculated using Kaplan-Meier curves and compared using log-rank tests. RESULTS: A cohort of 814 PDAC patients with pancreatoduodenectomy were analyzed. A total of 651 patients had LN involvement (80%). On multivariable analysis R1 resection was not an independent factor of worse OS and DFS in patients with LN involvement (HR 1.1, p = 0.565; HR 1.2, p = 0.174). Only tumor size, grade, and adjuvant chemotherapy were associated with OS and DFS. Median OS and DFS were similar between patients with R0 and R1 resections (23 vs. 20 months, p = 0.196; 15 vs. 14 months, p = 0.080). CONCLUSION: Resection status was not identified as predictor of OS or DFS in PDAC patients with LN involvement. Extensive surgery to achieve R0 resection in such patients might not influence the disease course.

Faster Return to Intended Oncologic Treatment (RIOT) After Trisectionectomy Does Not Translate to Better Outcomes.

BACKGROUND: Resection with trisectionectomy may necessitate liver molding for adequate future liver remnant (FLR), and subsequent complications can impact return to intended oncologic therapy (RIOT). This study evaluated whether a difference in RIOT exists with the use of molding and between liver molding techniques (associating liver partition and portal vein ligation for staged hepatectomy [ALPPS] and portal vein embolization [PVE]) with trisectionectomy. METHODS: A retrospective review evaluated trisectionectomies for malignancy. Outcomes were compared with and without molding, and RIOT was determined. RESULTS: Fifty-one patients underwent trisectionectomy: 11 ALPPS, 14 PVE, 26 without molding. 73% of ALPPS, 64% of PVE, and 58% without molding achieved RIOT (P = .971). There were no differences found in baseline characteristics, R0 rate, length of stay, readmission, complications, or mortality. Time to RIOT was significantly different (ALPPS: 3.3 months; PVE: 5.2 months; none: 2.4 months, P = .0203). There were no differences in recurrence or survival. CONCLUSIONS: Liver molding should not cause apprehension as there are no differences in achieving RIOT. Although technique alters time to RIOT, this does not translate into improved outcomes, implicating disease biology, and regeneration stimulus.

Operative Microwave Ablation for the Multimodal Treatment of Neuroendocrine Liver Metastases.

Background and Purpose: Operative microwave ablation (MWA) is a safe modality for treating hepatic tumors. The aim of this study is to present our 10-year, single-center experience of operative MWA for neuroendocrine liver metastases (NLM). Methods: A single-institution retrospective review of patients who underwent operative MWA for NLM was performed (2008-2018). Demographics, primary tumor site, operative approach, combined surgical operations, and carcinoid symptoms were recorded. Clinical outcomes for major complications, readmission, and mortality were analyzed 30 days postoperatively. Postablation imaging was evaluated for incomplete ablation/missed lesions, and surveillance imaging reviewed for local, regional, and metastatic recurrence. Results: Of the 50 patients (166 targeted lesions) who received MWA for NLM, 41 (82%) were treated with a minimally invasive approach, and 22 (44%) underwent MWA concomitant with hepatectomy and/or primary tumor resection. Within the study cohort 70% of patients were treated with curative intent with a 77% (27/35) success rate. Carcinoid symptoms were reported in 40% (20/50) of patients preoperatively, and MWA treatment improved symptoms in 19/20 patients. Incomplete ablation occurred in 1/166 treated lesions. Recurrence-free survival at 1 and 5 years was 86% and 28%, respectively. Overall survival at 1 and 5 years was 94% and 70%, respectively (median follow-up 32 months, range 0-116 months). Conclusion: Operative MWA is a versatile modality, which can be safe and effectively performed alone or combined with hepatectomy for NLM, preferably using a minimally invasive approach, to achieve symptom control and possibly improve survival.

Current trends in vena cava reconstructive techniques with major liver resection: a systematic review.

PURPOSE: Historically, invasion of the inferior vena cava (IVC) represented advanced and often unresectable hepatic disease. With surgical and anesthetic innovations, IVC resection and reconstruction have become feasible in selected patients. This review assesses technical variations in reconstructive techniques and post-operative management. METHODS: A comprehensive literature search was performed according to PRISMA. Inclusion criteria were (i) peer-reviewed articles in English; (ii) at least three cases; (iii) hepatic IVC resection and reconstruction (January 2015-March 2020). Primary outcomes were reconstructive technique, anti-thrombotic regimen, post-operative IVC patency, and infection. Secondary outcomes included post-operative complications and malignant disease survival. RESULTS: Fourteen articles were included allowing for investigation of 351 individual patients. Analysis demonstrated significant heterogeneity in surgical reconstructive technique, anti-thrombotic management, and post-operative monitoring of patency. There was increased utilization of ex vivo approaches and decreased use of venovenous bypass compared with previously published reviews. CONCLUSION: This review of literature published between 2015 and 2020 reveals persistent heterogeneity of hepatic IVC reconstructive techniques and peri-operative management. Increased utilization of ex vivo approaches and decreased use of venovenous bypass point towards improved operative techniques, peri-operative management, and anesthesia. In order to gain evidence for consensus on management, a registry would be beneficial.

Pathologic response translates to improved patient survival after locoregional treatment for hepatocellular carcinoma: the importance of minimally invasive microwave ablation.

BACKGROUND: Hepatectomy or transplantation can serve as curative treatment for early-stage hepatocellular carcinoma (HCC). Unfortunately, as progression remains a reality, locoregional therapies (LRT) for curative or bridging intent have become common. Efficacy on viability, outcomes, and accuracy of imaging should be defined to guide treatment. METHODS: Patients with HCC who underwent minimally invasive (MIS) microwave ablation (MWA), transarterial chemoembolization (TACE), or both (MIS-MWA-TACE) prior to hepatectomy or transplantation were identified. Tumor response and preoperative computed tomography (CT) accuracy were assessed and compared to pathology. Clinical and oncologic outcomes were compared between MIS-MWA, TACE, and MIS-MWA-TACE. RESULTS: Ninety-one patients, with tumors from all stages of the Barcelona Clinic Liver Cancer (BCLC) staging, were identified who underwent LRT prior to resection or transplant. Fourteen patients underwent MIS-MWA, 46 underwent TACE, and 31 underwent both neoadjuvantly. TACE population was older; otherwise, there were no differences in demographics. Fifty-seven percent of MIS-MWA patients had no viable tumor on pathology whereas only 13% of TACE patients and 29% of MIS-MWA-TACE patients had complete destruction (p = 0.004). The amount of remaining viable tumor in the explant was also significantly different between groups (MIS-MWA: 17.2%, TACE: 48.7%, MIS-MWA-TACE: 18.6%; p ≤ 0.0001). Compared with TACE, the MIS-MWA and MIS-MWA-TACE groups had significantly improved overall survival (MIS-MWA: 99.94 months, TACE: 75.35 months, MIS-MWA-TACE: 140 months; p = 0.017). This survival remained significant with stratification by tumor size. CT accuracy was found to be 50% sensitive and 86% specific for MIS-MWA. For TACE, CT had an 82% sensitivity and 33% specificity and for MIS-MWA-TACE, there was a 42% sensitivity and 78% specificity. CONCLUSION: The impact of locoregional treatments on tumor viability is distinct and superior with MIS-MWA alone and MIS-MWA-TACE offering significant advantage over TACE alone. The extent of this effect may be implicated in the improved overall survival.

Advances in borderline resectable pancreatic adenocarcinoma.

Pancreatic adenocarcinoma is one of the most lethal cancers in oncology. Pancreatic cancer is the third most common cause of cancer-related mortality in the United States. As the years have progressed, the importance of a multidisciplinary and multimodal approach to pancreatic cancer care has been recognized and is now recommended in all major society guidelines. A subset of pancreatic cancer, borderline resectable pancreatic cancer (BRPC), has emerged as a distinct clinical entity for which specialized treatment plans are now being developed. The medical oncologist, surgical oncologist, and radiation oncologist must work jointly to help deliver the best clinical outcome for the patient with pancreatic cancer. In this discussion, we describe the current state of surgical, locoregional therapies and systemic therapy in BRPC.

Prognostic impact of the Bismuth-Corlette classification: Higher rates of local unresectability in stage IIIb hilar cholangiocarcinoma.

BACKGROUND: The Bismuth-Corlette (BC) classification is used to categorize hilar cholangiocarcinoma by proximal extension along the biliary tree. As the right hepatic artery crosses just behind the left bile duct, we hypothesized that BC IIIb tumors would have a higher likelihood of local unresectability due to involvement of the contralateral artery. METHODS: A retrospective review of a prospectively maintained database identified patients with hilar cholangiocarcinoma taken to the operating room for intended curative resection between April 2008 and September 2016. Cases were assigned BC stages based on preoperative imaging. RESULTS: Sixty-eight patients were included in the study. All underwent staging laparoscopy after which 16 cases were aborted for metastatic disease. Of the remaining 52 cases, 14 cases were explored and aborted for locally advanced disease. Thirty-eight underwent attempt at curative resection. After excluding cases aborted for metastatic disease, the chance of proceeding with resection was 55.6% for BC IIIb staged lesions compared to 80.0% of BC IIIa lesions and to 82.4% for BC I-IIIa staged lesions (P < 0.05). About 44.4% of BC IIIb lesions were aborted for locally advanced disease versus 17.6% of remaining BC stages. CONCLUSIONS: When hilar cholangiocarcinoma is preoperatively staged as BC IIIb, surgeons should anticipate higher rates of locally unresectable disease, likely involving the right hepatic artery.

Modifying Interhospital Hepatopancreatobiliary Transfers Based on Predictive Analytics: Moving from a Center of Excellence to a Health-Care System of Excellence.

Regionalization of complex surgical care has increased interhospital transfers to quaternary centers within large health-care systems. Risk-based patient selection is imperative to improve resource allocation without compromising care. This study aimed to develop predictive models for identifying low-risk patients for transfer to a fully integrated satellite hepatopancreatobiliary (HPB) service in the northeast region of the health-care system. HPB transfers to the quaternary center over 15 months from hospitals in proximity to the satellite HPB center. A predictive tool was developed based on simple pretransfer variables and outcomes for 30-day major complications (Clavien grade ≥ 3), readmission, and mortality. Thresholds for "low risk" were set at different SDs below mean for each model. Predictive models were developed from 51 eligible northeast region patient transfers for major complications (Brier score 0.1948, receiver operator characteristic (ROC) 0.7123, P = 0.0009), readmission (Brier score 0.0615, ROC 0.7368, P = 0.0020), and mortality (Brier score 0.0943, ROC 0.7989, P = 0.0023). Thresholds set from 2 SD below the mean for all models identified 2 as "low risk." Adjusting the threshold for the serious complication model to only 1 SD below the mean increased the "low-risk" cohort to five patients. These models demonstrate an easy-to-use tool to assist surgeons in identifying low-risk patients for diversion to a fully integrated satellite center. Improved interhospital transfers within a region could begin a transition from centers of excellence toward health-care systems of excellence.

Minimally Invasive Surgical Management as Effective First-Line Treatment of Large Pyogenic Hepatic Abscesses.

Management of pyogenic hepatic abscesses (PHA) varies among surgeons and institutions. Recent studies have advocated for first-line percutaneous drainage (PD) of all accessible hepatic abscesses, with surgery reserved as rescue only. Our study aimed to internally validate an established multimodal algorithm for PHA at a high-volume hepatopancreatobiliary center. Patients treated by the hepatopancreatobiliary service for PHA were retrospectively reviewed from 2008 through 2018. The algorithm defined intended first-line treatment as antibiotics for type I abscesses (<3 cm), PD for type II (≥3, unilocular), and surgical intervention (minimally invasive drainage or resection, when possible) for type III (≥3 cm, multilocular). Outcomes were compared between patients who received first-line treatment following the algorithm versus alternate therapy. Of 330 patients with PHA, 201 met inclusion criteria. Type III abscesses had significantly lower failure following algorithmic approach with surgery compared with PD (4% vs 28%, P = 0.018). Type II abscesses failed first-line PD in 27 per cent (13/48) with 11 patients requiring surgical rescue, whereas first-line surgery failed in only 13 per cent (2/15). No deaths occurred after any surgical intervention, and there was no statistical difference in major complications between first-line surgical intervention and PD for type II or III abscesses. These results support the algorithmic approach and demonstrate that minimally invasive surgical intervention is a safe and effective modality for large PHA. We recommend that select patients with large, complex abscesses should be considered for a first-line minimally invasive surgical approach depending on surgical experience and available resources.

Clinically Meaningful Laboratory Protocols Reduce Hospital Charges Based on Institutional and ACS-NSQIP® Risk Calculators in Hepatopancreatobiliary Surgery.

Postoperative laboratory testing is an underrecognized but substantial contributor to health-care costs. We aimed to develop and validate a clinically meaningful laboratory (CML) protocol with individual risk stratification using generalizable and institution-specific predictive analytics to reduce laboratory testing and maximize cost savings for low-risk patients. An institutionally based risk model was developed for pancreaticoduodenectomy and hepatectomy, and an ACS-NSQIP®-based model was developed for distal pancreatectomy. Patients were stratified in each model to the CML by individual risk of major complications, readmission, or death. Clinical outcomes and estimated cost savings were compared with those of a historical cohort with standard of care. Over 34 months, 394 patients stratified to the CML for pancreaticoduodenectomy or hepatectomy saved an estimated $803,391 (44.4%). Over 13 months, 52 patients stratified to the CML for distal pancreatectomy saved an estimated $81,259 (30.5%). Clinical outcomes for 30-day major complications, readmission, and mortality were unchanged after implementation of either model. Predictive analytics can target low-risk patients to reduce laboratory testing and improve cost savings, regardless of whether an institutional or a generalized risk model is implemented. Broader application is important in patient-centered health care and should transition from predictive to prescriptive analytics to guide individual care in real time.

Efficacy of a Laparoscopic Saline-Coupled Bipolar Sealer in Minimally Invasive Hepatobiliary Surgery.

Hepatic resection presents unique surgical challenges to reduce blood loss during parenchymal division. The development of saline-coupled bipolar devices, in which hemostasis is achieved at lower temperatures than electrocautery or other bipolar sealing devices, have been employed for open hepatic resection. Saline-coupled bipolar devices have now become available for minimally invasive use. The goals of this study were to evaluate the feasibility and safety of a laparoscopic saline-coupled bipolar device for minimally invasive hepatectomy. Seventeen patients (median age 66 years, range 36-81) were consented for inclusion and enrolled. Patient demographics, intraoperative data, and surgeon feedback were collected. Seven robot-assisted partial hepatectomies, 9 laparoscopic partial hepatectomies, and 1 laparoscopic cholecystectomy with liver abscess resection were performed. Average operating time was 222 ± 33 minutes (median 188 minutes; range 61-564 minutes) with no difference between robotic versus laparoscopic time. Successful seals were achieved in all cases following application of 150 to 200 J energy (average 179 ± 3 J, average time to achieve a successful seal 9.3 ± 2.7 minutes). Estimated blood loss was 362 ± 74 mL (median 300 mL, range 5-1200 mL) and 3/17 patients received intraoperative blood transfusion. No bile leaks were detected in any of the patients. Median length of stay was 5 days (range 1-20 days), and there were no readmissions within 30 days. Postoperative morbidity occurred in 5/17 patients, all of which were Clavien Grade 1. There was no mortality within 90 days or complications requiring a return to the operating room, and there were no liver-specific morbidities. These data suggest the laparoscopic Aquamantys device represents a useful device for use in minimally invasive liver resection.

Experimental High-Frequency Irreversible Electroporation Using a Single-Needle Delivery Approach for Nonthermal Pancreatic Ablation In Vivo.

PURPOSE: To investigate the feasibility of single-needle high-frequency irreversible electroporation (SN-HFIRE) to create reproducible tissue ablations in an in vivo pancreatic swine model. MATERIALS AND METHODS: SN-HFIRE was performed in swine pancreas in vivo in the absence of intraoperative paralytics or cardiac synchronization using 3 different voltage waveforms (1-5-1, 2-5-2, and 5-5-5 [on-off-on times (µs)], n = 6/setting) with a total energized time of 100 µs per burst. At necropsy, ablation size/shape was determined. Immunohistochemistry was performed to quantify apoptosis using an anticleaved caspase-3 antibody. A numerical model was developed to determine lethal thresholds for each waveform in pancreas. RESULTS: Mean tissue ablation time was 5.0 ± 0.2 minutes, and no cardiac abnormalities or muscle twitch was detected. Mean ablation area significantly increased with increasing pulse width (41.0 ± 5.1 mm2 [range 32-66 mm2] vs 44 ± 2.1 mm2 [range 38-56 mm2] vs 85.0 ± 7.0 mm2 [range 63-155 mm2]; 1-5-1, 2-5-2, 5-5-5, respectively; p < 0.0002 5-5-5 vs 1-5-1 and 2-5-2). The majority of the ablation zone did not stain positive for cleaved caspase-3 (6.1 ± 2.8% [range 1.8-9.1%], 8.8 ± 1.3% [range 5.5-14.0%], and 11.0 ± 1.4% [range 7.1-14.2%] cleaved caspase-3 positive 1-5-1, 2-5-2, 5-5-5, respectively), with significantly more positive staining at the 5-5-5 pulse setting compared with 1-5-1 (p < 0.03). Numerical modeling determined a lethal threshold of 1114 ± 123 V/cm (1-5-1 waveform), 1039 ± 103 V/cm (2-5-2 waveform), and 693 ± 81 V/cm (5-5-5 waveform). CONCLUSIONS: SN-HFIRE induces rapid, predictable ablations in pancreatic tissue in vivo without the need for intraoperative paralytics or cardiac synchronization.

Cholangitis: Causes, Diagnosis, and Management.

Acute cholangitis remains a potentially lethal disease if not appropriately diagnosed in a timely fashion. Modern diagnostic and therapeutic modalities have greatly decreased mortality from acute cholangitis. This article aims to provide an up-to-date synopsis of empirically tested diagnostic criteria as well as an overview of the expanding interventions available.

Retrospective Validation of an Algorithmic Treatment Pathway for Necrotizing Pancreatitis.

The role of surgical intervention for necrotizing pancreatitis has evolved; however, no widely accepted algorithm has been established to guide timing and optimal modality in the minimally invasive era. This study aimed to retrospectively validate an established institutional timing- and physiologic-based algorithm constructed from evidence-based guidelines in a high-volume hepatopancreatobiliary center. Patients with necrotizing pancreatitis requiring early (≤six weeks from symptom onset) or delayed (>six weeks) surgical intervention were reviewed over a four-year period (n = 100). Early intervention was provided through laparoscopic drain-guided retroperitoneal debridement (n = 15) after failed percutaneous drainage unless they required an emergent laparotomy (due to abdominal compartment syndrome, bowel necrosis/perforation, or hemorrhage) after which conservative, sequential open necrosectomy was performed (n = 47). Robot-assisted (n = 16) versus laparoscopic (n = 22) transgastric cystgastrostomy for the delayed management of walled-off pancreatic necrosis was compared, including patient factors, operative characteristics, and 90-day clinical outcomes. Major complications after early debridement were similarly high (open 25% and drain-guided 27%), yet 90-day mortality was low (open 8.5% and drain-guided 7.1%). Patient and operative characteristics and 90-day outcomes were statistically similar for robotic versus laparoscopic transgastric cystogastrostomy. Our evidence-based algorithm provides a stepwise approach for the management of necrotizing pancreatitis, emphasizing minimally invasive early and late interventions when feasible with low morbidity and mortality. Robot-assisted transgastric cystogastrostomy is an acceptable alternative to a laparoscopic approach for the delayed treatment of walled-off pancreatic necrosis.

The impact of intraoperative goal-directed fluid therapy on complications after pancreaticoduodenectomy.

INTRODUCTION: Optimal fluid balance is critical to minimize anastomotic edema in patients undergoing pancreaticoduodenectomy. We examined the effects of decreased fluid administration on rates of postoperative pancreatic leak and delayed gastric emptying. METHODS: Retrospective study of 105 patients undergoing pancreaticoduodenectomy at a single institution from January 2015 through July 2016. Stroke volume variation (SVV) was tracked and titrated during the procedure. A comparative analysis of postoperative complications was performed between patients with a median SVV < 12 during the extirpative and reconstructive phases of the procedure compared with patients with an SVV ≥ 12. RESULTS: Of 64 patients who met selection criteria, 42 (65.6%) had a SVV < 12 and 22 (34.4%) had a SVV ≥ 12. Patients with an SVV ≥ 12 during the extirpative phase of the procedure had lower rates of postoperative pancreatic leaks compared to patients with an SVV < 12 (5.9% vs 21.3%)). Patients with an SVV ≥ 12 during the extirpative phase had lower rates of postoperative delayed gastric emptying compared to patients with an SVV < 12 (41.2% vs 46.8%). CONCLUSION: Goal-directed fluid restriction before the reconstructive phase of pancreaticoduodenectomy may contribute to lower postoperative rates of pancreatic leak and delayed gastric emptying.