Clinical validation of the international study group of pancreatic surgery (ISGPS) definition for post-pancreatectomy acute pancreatitis.

BACKGROUND: The diagnosis of postoperative or post-pancreatectomy acute pancreatitis (PPAP) is controversial. In 2021, the International Study Group of Pancreatic Surgery (ISGPS) published the first unifying definition and grading system for PPAP. This study sought to validate recent consensus criteria, using a cohort of patients undergoing pancreaticoduodenectomy (PD) in a high-volume pancreaticobiliary specialty unit. METHODS: All consecutive patients undergoing PD at a tertiary referral centre between January 2016 and December 2021 were retrospectively reviewed. Patients with serum amylase recorded within 48h from surgery were included for analysis. Postoperative data were extracted and evaluated against the ISGPS criteria, including the presence of postoperative hyperamylasaemia, radiologic features consistent with acute pancreatitis, and clinical deterioration. RESULTS: A total of 82 patients were evaluated. The overall incidence of PPAP was 32% (26/82) in this cohort, of which 3/26 demonstrated postoperative hyperamylasaemia and 23/26 had clinically relevant PPAP (Grade B or C) when correlated radiologic and clinical criteria. CONCLUSIONS: This study is among the first to apply the recently published consensus criteria for PPAP diagnosis and grading to clinical data. While the results support their utility in establishing PPAP as a distinct post-pancreatectomy complication, there remains a need for future large-scale validation studies.

The Role of Targeted Versus Standard Antibiotic Prophylaxis in Pancreatoduodenectomy in Reducing Postoperative Infectious Complications: A Systematic Review and Meta-analysis.

INTRODUCTION: Infectious complications are common after pancreatoduodenectomy, which in turn are associated with preoperative biliary drainage. Current guidelines recommend a first-generation cephalosporin as perioperative antibiotic prophylaxis. However, some studies support the use of targeted antibiotics. The aim of this systematic review and meta-analysis is to evaluate the role of prophylactic targeted antibiotics compared to standard antibiotics in reducing postoperative infections after pancreatoduodenectomy. METHODS: A search from MEDLINE, EMBASE, and Cochrane library from 1946 to July 2020 was conducted. Studies were included if they compared targeted antibiotics with standard perioperative antibiotics while including outcome data on surgical site infections (SSI). Targeted therapy was defined as perioperative antibiotics targeting organisms prevalent in bile instrumentation or by culture data obtained from the patient or institution. Outcomes assessed were the rate of SSIs and their microbiology profile. Analyses included demographic data, perioperative antibiotics, postoperative outcomes including microbiology data, and meta-analysis was performed where applicable. RESULTS: Seven studies were included, with a total of 849 patients undergoing pancreatoduodenectomy. Targeted antibiotics were associated with a significantly lower rate of postoperative SSI compared to standard antibiotic therapy [21.1% vs 41.9%; risk ratios (RR) 0.55, 95% confidence interval 0.37-0.81]. Wound/incisional site infections and organ space infections were lower in patients receiving targeted antibiotic prophylaxis (RR 0.33, P = 0.0002 and RR 0.54, P = 0.0004, respectively). Enterococcus species were the most common bacteria reported. CONCLUSION: There was a significant reduction in overall SSI rates when targeted antibiotics was used. Current standard antibiotic prophylaxis is inadequate in covering microbes prevalent in postoperative infections developing after pancreatoduodenectomy.

The role of staging laparoscopy in pancreatic adenocarcinoma and its effect on patients' survival.

BACKGROUND: Prompt and accurate staging of pancreatic cancer is essential to distinguish patients to benefit from resection with curative intent and those with unresectable disease. A staging laparoscopy is used preoperatively to identify macroscopic or occult metastases not identified on imaging. This single-institution study aims to evaluate the role of staging laparoscopy in patients with pancreatic adenocarcinoma and its effect on overall survival. METHOD: Clinicopathologic data were evaluated for all patients undergoing staging laparoscopy for pancreatic adenocarcinoma from July 2014 to December 2019. The study identified 155 patients eligible for analysis. All patients were followed for at least 2 years. Clinical backgrounds, survival curves and prognostic factors were investigated. RESULTS: Resectability status among the cohort was 62 (40%) upfront resectable, 53 (34%) borderline resectable and 40 (26%) locally advanced disease. The median age was 69, with 44% male patients. Median CA19-9 value was 125 kU/L, and median CA125 value was 22 kU/L. Staging laparoscopy resulted in upstaging nine (15%) upfront resectable patients, five (9%) borderline resectable patients and ten (25%) locally advanced patients. There was positive cytology in 19 (12%), peritoneal deposits in six (4%) and peritoneal liver deposits in seven (5%) patients. Overall, the number needed to treat (NNT) to avoid an unnecessary laparotomy was eight patients. CONCLUSION: Staging laparoscopy continues to be a valuable investigation of pancreatic adenocarcinoma. In this institution, one in every eight patients undergoing a staging laparoscopy was upstaged to metastatic disease, thus avoiding an unnecessary laparotomy or a non-curative resection.

A multi-center post-market clinical study to confirm safety and performance of PuraStat® in the management of bleeding during open liver resection.

BACKGROUND: PuraStat® is a non-bioactive haemostatic agent that has demonstrated efficacy in a number of different surgical procedures. We performed a prospective multi-centre post-market study to evaluate the efficacy and safety of PuraStat® in liver resections performed for metastatic tumors. METHODS: This was a prospective cohort study. Patients undergoing liver resection for metastatic tumor were screened for eligibility, and included if they were ≥18 years old, undergoing open liver resection, had normal liver function, and required application of PuraStat® for haemostasis where standard haemostatic techniques were either insufficient or impractical. The primary endpoint was "time to haemostasis" (TTH). Secondary endpoints included blood loss, total postoperative drainage volume, transfusion of blood products, and ease of use. RESULTS: Eighty patients were included for analysis in the intention to treat population. 207 bleeding sites were treated with PuraStat. Of these, 190 (91.7%) bleeding sites reached haemostasis after PuraStat® application. Mean TTH (mm:ss) was 1:01 (SD 1:06, range 0:09-6:55). Ease of use of the product was described as either "excellent" or "good" in 78 (98.8%) patients. No serious adverse events were identified. CONCLUSION: This study confirms the safety, efficacy and ease of use of PuraStat® in the management of bleeding in liver surgery.

A unique urinary metabolomic signature for the detection of pancreatic ductal adenocarcinoma.

Our study aimed to identify a urinary metabolite panel for the detection/diagnosis of pancreatic ductal adenocarcinoma (PDAC). PDAC continues to have poor survival outcomes. One of the major reasons for poor prognosis is the advanced stage of the disease at diagnosis. Hence, identification of a novel and cost-effective biomarker signature for early detection/diagnosis of PDAC could lead to better survival outcomes. Untargeted metabolomics was employed to identify a novel metabolite-based biomarker signature for PDAC diagnosis. Urinary metabolites from 92 PDAC patients (56 discovery cohort and 36 validation cohort) were compared with 56 healthy volunteers using 1 H nuclear magnetic resonance spectroscopy. Multivariate (partial-least squares discriminate analysis) and univariate (Mann-Whitney's U-test) analyses were performed to identify a metabolite panel which can be used to detect PDAC. The selected metabolites were further validated for their diagnostic potential using the area under the receiver operating characteristic (AUROC) curve. Statistical analysis identified a six-metabolite panel (trigonelline, glycolate, hippurate, creatine, myoinositol and hydroxyacetone), which demonstrated high potential to diagnose PDAC, with AUROC of 0.933 and 0.864 in the discovery and validation cohort, respectively. Notably, the identified panel also demonstrated very high potential to diagnose early-stage (I and II) PDAC patients with AUROC of 0.897. These results demonstrate that the selected metabolite signature could be used to detect PDAC and will pave the way for the development of a urinary test for detection/diagnosis of PDAC.

RAF1 rearrangements are common in pancreatic acinar cell carcinomas.

There is now evidence that gene fusions activating the MAPK pathway are relatively common in pancreatic acinar cell carcinoma with potentially actionable BRAF or RET fusions being found in ~30%. We sought to investigate the incidence of RAF1 fusions in pancreatic malignancies with acinar cell differentiation. FISH testing for RAF1 was undertaken on 30 tumors comprising 25 'pure' acinar cell carcinomas, 2 mixed pancreatic acinar-neuroendocrine carcinomas, 1 mixed acinar cell-low grade neuroendocrine tumor and 2 pancreatoblastomas. RAF1 rearrangements were identified in 5 cases and confirmed by DNA and RNA sequencing to represent oncogenic fusions (GATM-RAF1, GOLGA4-RAF1, PDZRN3-RAF1, HERPUD1-RAF1 and TRIM33-RAF1) and to be mutually exclusive with BRAF and RET fusions, as well as KRAS mutations. Large genome-wide copy number changes were common and included 1q gain and/or 1p loss in all five RAF1 FISH-positive acinar cell carcinomas. RAF1 expression by immunohistochemistry was found in 3 of 5 (60%) of fusion-positive cases and no FISH-negative cases. Phospho-ERK1/2 expression was found in 4 of 5 RAF1-fusion-positive cases. Expression of both RAF1 and phospho-ERK1/2 was heterogeneous and often only detected at the tumor-stroma interface, thus limiting their clinical utility. We conclude that RAF1 gene rearrangements are relatively common in pancreatic acinar cell carcinomas (14.3% to 18.5% of cases) and can be effectively identified by FISH with follow up molecular testing. The combined results of several studies now indicate that BRAF, RET or RAF1 fusions occur in between one third and one-half of these tumors but are extremely rare in other pancreatic malignancies. As these fusions are potentially actionable with currently available therapies, a strong argument can be made to perform FISH or molecular testing on all pancreatic acinar cell carcinomas.

Risk factors for development of diabetes mellitus (Type 3c) after partial pancreatectomy: A systematic review.

OBJECTIVES: Type 3c diabetes mellitus (T3cDM) occurring post pancreatectomy can be challenging to treat due to the frequent combination of decreased circulating levels of insulin and glucagon and concurrent exocrine insufficiency. Relatively, little is known regarding the risk factors for development of T3cDM post pancreatectomy. Our aim was to review the literature and assess what is known of the risk factors for the development of new-onset DM following partial pancreatic resection and where possible determines the incidence, time of onset and the management approach to hyperglycaemia in this context. DESIGN: Medline and Embase databases were reviewed using specific keyword criteria. Original manuscripts published in 1990 or later included. Articles with study population <20, lacking information on new-onset DM, follow-up duration or specifically targeting rare procedures/pathology were excluded. The Newcastle Ottawa Quality Assessment form was applied. Results reported according to PRISMA guidelines. Pooled effect size calculated using random effects model. PATIENTS: Thirty six articles were identified that described a total of 5636 patients undergoing pancreaticoduodenectomy, 3922 patients having distal pancreatectomy and 315 with central pancreatectomy. RESULTS: The incidence of new-onset DM was significantly different between different types of resection from 9% to 24% after pancreaticoduodenectomy (pooled estimate 16%; 95% CI: 14%-17%), 3%-40% after distal pancreatectomy (pooled estimate 21%; 95% CI: 16%-25%) and 0%-14% after central pancreatectomy (pooled estimate 6%; 95% CI: 3%-9%). Surgical site, higher preoperative HbA1c, fasting plasma glucose and lower remnant pancreatic volume had strongest associations with new-onset DM. CONCLUSIONS: This systematic review supports that risk of development of T3cDM is associated with type of pancreatic resection, lower remnant pancreatic volume and higher preoperative HbA1c.

Neoadjuvant therapy for pancreatic cancer changes the composition of the pancreatic parenchyma.

BACKGROUND: Postoperative pancreatic fistula (POPF) remains a prominent complication following pancreatic cancer resections. The primary aim of this study was to evaluate the histological changes that occur in the pancreas due to neoadjuvant therapy (NAT) by comparing the acinar, collagen and fat scores in resected PDAC specimens of patients who did and did not receive NAT. Secondary aims included (1) the difference in rates of POPF in PDAC patients who received NAT versus upfront resection; and (2) the association between acinar/collagen/fat scores and the development of POPF. METHODS: Consecutive patients who underwent pancreaticoduodenectomy for PDAC, with and without NAT were included for analysis. Acinar, collagen and fat scores were determined from histology slides of the pancreatic resection margin. RESULTS: One hundred and thirty-four patients were included. There was a significant decrease in the median acinar score (48 vs 23, p = 0.003) and increase in the collagen score (28 vs 50, p = 0.011) for patients who received NAT and a significant correlation with the number of cycles of NAT. This study found no statistical difference between NAT and the development of POPF. CONCLUSION: The use of NAT in the treatment of PDAC changes the composition of the pancreas.

SELDI-TOF MS Analysis of Hepatocellular Carcinoma in an Australian Cohort.

BACKGROUND: Hepatocellular carcinoma (HCC) is a common cause of cancer death worldwide. Resection offers the best chance of long-term survival, but a consistent adverse prognostic factor is the presence of microvascular invasion (MVI). In this study, surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS), a high throughput method of analyzing complex samples, was used to explore differentially expressed proteins between HCC and adjacent nontumour liver tissue (ANLT). These findings were correlated with clinical outcomes. MATERIALS AND METHODS: From 2002 to 2011, tumor and ANLT were collected from patients who underwent liver resection and these samples were later prepared for SELDI-TOF MS. Output data were then used to identify proteins capable of discriminating HCC from ANLT. Proteins from the multivariate analysis were then analyzed to determine prognostic factors and the m/z ratios of these proteins were entered into the ExPASy database to infer potential candidates. RESULTS: During the study period, 30 patients had SELDI-TOF MS performed on their HCC and ANLT samples. On multivariate analysis, a panel of four proteins-m/z 5840, m/z 8921, m/z 9961, and m/z 25,872-discriminated HCC from ANLT with an area under the ROC curve of 0.954 (P < 0.001). On prognostic factor assessment, decreased m/z 9961 was significantly associated with the presence of MVI (P = 0.025) and shorter disease-free survival (P = 0.045) in our patients. A potential candidate for this protein was coxsackievirus and adenovirus receptor, isoform 3 (CAR 3/7), which helps maintain tight junction integrity. CONCLUSIONS: Using SELDI TOF-MS, we identified a panel of four proteins with excellent discriminative capacity between HCC and ANLT. Of these, m/z 9961 was the only protein significantly associated with a known poor prognostic factor (presence of MVI) and survival (shorter disease-free survival). While loss of CAR 3/7 could lead to MVI, further research is warranted to validate the identity of protein m/z 9961.

Management of post-pancreatectomy haemorrhage using resuscitative endovascular balloon occlusion of the aorta.

BACKGROUND: Delayed massive post-pancreatectomy haemorrhage (PPH) is a highly lethal complication after pancreatectomy. Angiographic procedures have led to improved outcomes in the management of these patients. In the setting of an acute haemorrhage, laparotomy and packing are often required to help stablise the patient. However, re-operative surgery in the post-pancreatectomy setting is technically challenging. METHODS: A novel strategy of incorporating the resuscitative endovascular balloon occlusion of the aorta (REBOA) is described. RESULTS: Two patients where the specific application of this technique uses the REBOA were described. CONCLUSION: The REBOA serves as a useful adjunct in haemorrhage control and haemodynamic stablisation to allow successful management of delayed massive PPH.

Density and enhancement of the pancreatic tail on computer tomography predicts acinar score and pancreatic fistula after pancreatoduodenectomy.

BACKGROUND: Acinar score calculated at the pancreatic resection margin is associated with postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD). The present study evaluates the association between (i) computed tomography (CT) density of the pancreas and the acinar score of the pancreatic resection margin, and (ii) CT density of the pancreas and POPF after PD. METHODS: Consecutive patients who underwent PD were included for analysis. CT densities of the pancreatic head, neck, body and tail were measured in non-contrast (NC), arterial (ART) and portal venous (PV) phases. Histologic slides of the pancreatic resection margin were scored for acinar cell density. RESULTS: Ninety patients were included for analysis. Non-contrast density of the pancreatic tail was a good predictor of POPF (AUROC 0.704, p = 0.036), and a cut-off value of >40 Hounsfield units predicted POPF with 70.0% sensitivity and 73.4% specificity. The ratio of densities between PV and NC phases in the pancreatic tail was also a good predictor of POPF (AUROC 0.712, p = 0.030), and a cut-off value of <2.29 predicted POPF with 70.9% sensitivity and 80% specificity. CONCLUSION: Non-contrast CT density of the pancreatic tail correlates with acinar cell density of the pancreatic resection margin and predicts the development of POPF after PD.

Acinar cell density at the pancreatic resection margin is associated with post-pancreatectomy pancreatitis and the development of postoperative pancreatic fistula.

BACKGROUND: There has been recent evidence supporting post-pancreatectomy pancreatitis as a factor in the development of postoperative pancreatic fistula (POPF). The aims of this study were to evaluate: (i) the correlation of the acinar cell density at the pancreatic resection margin with the intra-operative amylase concentration (IOAC) of peri-pancreatic fluid, postoperative pancreatitis, and POPF; and (ii) the association between postoperative pancreatitis on the first postoperative day and POPF. METHODS: Consecutive patients who underwent pancreatic resection between June 2016 and July 2017 were included for analysis. Fluid for IOAC was collected, and amylase concentration was determined in drain fluid on postoperative days 1, 3, and 5. Serum amylase and lipase and urinary trypsinogen-2 concentrations were determined on the first postoperative day. Histology slides of the pancreatic resection margin were scored for acinar cell density. RESULTS: Sixty-one patients were included in the analysis. Acinar cell density significantly correlated with IOAC (r = 0.566, p < 0.001), and was significantly associated with postoperative pancreatitis (p < 0.001), and POPF (p = 0.003). Postoperative pancreatitis was significantly associated with the development of POPF (OR 17.81, 95%CI 2.17-145.9, p = 0.001). DISCUSSION: The development of POPF may involve a complex interaction between acinar cell density, immediate leakage of pancreatic fluid, and postoperative pancreatitis.

Lipase-to-Amylase Ratio for the Prediction of Clinically Relevant Postoperative Pancreatic Fistula Following Pancreaticoduodenectomy.

OBJECTIVE: Postoperative pancreatic fistula (POPF) represents a leading cause of morbidity and mortality following major pancreatic resections. This study aimed to evaluate the use of postoperative drain fluid lipase-to-amylase ratio (LAR) for the prediction of clinically relevant fistulae (CR-POPF). METHODS: Consecutive patients undergoing pancreaticoduodenectomy between 2017 and 2021 at a tertiary centre were retrospectively reviewed. Univariable and multivariable analyses were performed to identify predictors for CR-POPF (ISGPS grade B/C). Receiver operating characteristic (ROC) curve analyses were conducted to evaluate the performance of LAR and determine optimum prediction thresholds. RESULTS: Among 130 patients, 28 (21.5%) developed CR-POPF. Variables positively associated with CR-POPF included soft gland texture, acinar cell density, diagnosis other than PDAC or chronic pancreatitis, resection without neoadjuvant therapy, and postoperative drain fluid lipase, amylase, and LAR (all P <0.05). Multivariable regression analysis identified LAR as an independent predictor of CR-POPF ( P <0.05). ROC curve analysis showed that LAR had moderate ability to predict CR-POPF on POD1 (AUC,0.64; 95%CI,0.54-0.74) and excellent ability on POD3 (AUC,0.85; 95%CI,0.78-0.92) and POD 5 (AUC,0.86; 95%CI,0.79-0.92). Optimum thresholds were consistent over PODs 1 to 5 (ratio>2.6) and associated with 92% sensitivity and 46% to 71% specificity. CONCLUSIONS: Postoperative drain fluid LAR represents a reliable predictor for the development of CR-POPF. With early prognostication, the postoperative care of patients at risk of developing high-grade fistulas may be optimized.

Systematic Review of Preoperative Prognostic Biomarkers in Perihilar Cholangiocarcinoma.

Perihilar cholangiocarcinoma (pCCA) is an uncommon malignancy with generally poor prognosis. Surgery is the primary curative treatment; however, the perioperative mortality and morbidity rates are high, with a low 5-year survival rate. Use of preoperative prognostic biomarkers to predict survival outcomes after surgery for pCCA are not well-established currently. This systematic review aimed to identify and summarise preoperative biomarkers associated with survival in pCCA, thereby potentially improving treatment decision-making. The Embase, Medline, and Cochrane databases were searched, and a systematic review was performed using the PRISMA guidelines. English-language studies examining the association between serum and/or tissue-derived biomarkers in pCCA and overall and/or disease-free survival were included. Our systematic review identified 64 biomarkers across 48 relevant studies. Raised serum CA19-9, bilirubin, CEA, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and tumour MMP9, and low serum albumin were most associated with poorer survival; however, the cutoff values used widely varied. Several promising molecular markers with prognostic significance were also identified, including tumour HMGA2, MUC5AC/6, IDH1, PIWIL2, and DNA index. In conclusion, several biomarkers have been identified in serum and tumour specimens that prognosticate overall and disease-free survival after pCCA resection. These, however, require external validation in large cohort studies and/or in preoperatively obtained specimens, especially tissue biopsy, to recommend their use.

Kidney Transplantation Outcomes From Uncontrolled Donation After Circulatory Death: A Systematic Review and Meta-analysis.

BACKGROUND: Uncontrolled donation after circulatory death (uDCD) is a potential additional source of donor kidneys. This study reviewed uDCD kidney transplant outcomes to determine if these are comparable to controlled donation after circulatory death (cDCD). METHODS: MEDLINE, Cochrane, and Embase databases were searched. Data on demographic information and transplant outcomes were extracted from included studies. Meta-analyses were performed, and risk ratios (RR) were estimated to compare transplant outcomes from uDCD to cDCD. RESULTS: Nine cohort studies were included, from 2178 uDCD kidney transplants. There was a moderate degree of bias, as 4 studies did not account for potential confounding factors. The median incidence of primary nonfunction in uDCD was 12.3% versus 5.7% for cDCD (RR, 1.85; 95% confidence intervals, 1.06-3.23; P = 0.03, I 2 = 75). The median rate of delayed graft function was 65.1% for uDCD and 52.0% for cDCD. The median 1-y graft survival for uDCD was 82.7% compared with 87.5% for cDCD (RR, 1.43; 95% confidence intervals, 1.02-2.01; P = 0.04; I 2 = 71%). The median 5-y graft survival for uDCD and cDCD was 70% each. Notably, the use of normothermic regional perfusion improved primary nonfunction rates in uDCD grafts. CONCLUSIONS: Although uDCD outcomes may be inferior in the short-term, the long-term outcomes are comparable to cDCD.

Suction test to demonstrate the peritoneal edge during laparoscopic extraperitoneal inguinal hernia repair.

INTRODUCTION: Inadequate peritoneal dissection from retroperitoneal structures may account for a large number of hernia recurrences amongst surgeons and trainees who are new to totally extraperitoneal (TEP) laparoscopic inguinal hernia repair. In this paper, we describe a simple dynamic test that allows surgeons to better appreciate the peritoneal edge during the initial dissection phase of TEP inguinal hernia repair, allowing for more adequate dissection of the peritoneum from retroperitoneal structures before placement of mesh. METHODS: Data from a single surgeon was collected on 113 consecutive patients who underwent laparoscopic TEP inguinal hernia repair at the Royal North Shore Hospital in Sydney. The data was retrospectively reviewed to determine the number of cases in which the suction test led to further peritoneal dissection prior to mesh placement. OPERATIVE TECHNIQUE: After balloon dissection of the pre-peritoneal space and initial dissection of peritoneum and sac from retroperitoneal structures, a laparoscopic suction device is used to aspirate the insufflated gas from the pre-peritoneal space to cause the peritoneum to bulge anteriorly, thus demonstrating the edge of the peritoneal reflection. Further dissection is performed if deemed necessary at this point, and the mesh is placed over the hernia defect. RESULTS: 136 TEP hernia repairs were performed in 113 patients. In 26 (23 %) of patients, the abovementioned technique was of particular value resulting in further dissection of peritoneum prior to mesh placement. There were no complications as a direct result of the test. CONCLUSION: This dynamic suction test is a risk-free and useful operative tool for surgeons and trainees who are new to TEP inguinal hernia repair, and provides a definitive way of identifying the peritoneal reflection to ensure the peritoneum has been dissected adequately prior to mesh placement.

Reducing unplanned general surgical readmissions: a review of the Australian and New Zealand National Surgical Quality Improvement Program Database.

BACKGROUND: Unplanned surgical readmissions are an important indicator of quality care and are a key focus of improvement programs. The aims of this study were to evaluate the factors that lead to unplanned hospital readmissions in patients undergoing general surgical procedures and to identify preventable readmissions. METHODS: A retrospective review of the American College of Surgeons National Surgical Quality Improvement Program database from 2016 to 2020 at a tertiary hospital was conducted to identify patients undergoing a general surgical procedure. Various perioperative parameters were studied to identify risk factors and reasons for unplanned readmission. Preventable readmissions were identified. RESULTS: A total of 3069 patients underwent a general surgical procedure. Of these, the overall unplanned readmission rate was 8.8% (n = 247). The most common reason for readmission was associated with surgical site infections (n = 112, 44.3%) followed by pain (n = 50, 20.2%), with over 45% deemed as preventable readmissions. Factors associated with increased risk of readmission included older age, longer index length of stay, prolonged operative time, elective procedures, higher ASA score and contaminated procedures. CONCLUSION: Unplanned readmissions are more likely to occur in patients who develop postoperative complications. Understanding factors associated with readmissions may facilitate targeted quality improvement projects that reduce hospital readmission after surgery.

Evolution of laparoscopic pancreaticoduodenectomy at Westmead Hospital.

BACKGROUND: Despite its proposed benefits, laparoscopic pancreaticoduodenectomy (LPD) has not been widely adopted due to its technical complexity and steep learning curve. The aim of this study was to report a single surgeon's experience in the stepwise implementation of LPD and evolution of technique over a nine-year period in a moderate-high volume unit. METHODS: Carefully selected patients underwent LPD initially by hybrid approach (laparoscopic resection and open reconstruction), which evolved into a total LPD (laparoscopic resection and reconstruction). Data was prospectively collected to include patient characteristics, intraoperative data, evolution of technique and postoperative outcomes. RESULTS: A total of 25 patients underwent hybrid LPD (HLPD) and 20 patients underwent total LPD (TLPD). There was no 90-day mortality. Three patients developed a postoperative pancreatic fistula (POPF), all of which occurred in patients undergoing HLPD. There was no POPF in 20 consecutive TLPD. There was no evidence of anastomotic strictures in the hepaticojejunostomy in patients undergoing TLPD at long term follow up. CONCLUSION: A gradual and cautious progression from HLPD to TLPD is essential to ensure safe implementation into a unit. LPD should only be considered in carefully selected patients, with outcomes subjected to regular and rigorous independent audit.

Gene expression profiling of pancreatic ductal adenocarcinomas in response to neoadjuvant chemotherapy.

AIM: Pancreatic ductal adenocarcinoma (PDAC) has the lowest survival rate of all major cancers. Chemotherapy is the mainstay systemic therapy for PDAC, and chemoresistance is a major clinical problem leading to therapeutic failure. This study aimed to identify key differences in gene expression profile in tumors from chemoresponsive and chemoresistant patients. METHODS: Archived formalin-fixed paraffin-embedded tumor tissue samples from patients treated with neoadjuvant chemotherapy were obtained during surgical resection. Specimens were macrodissected and gene expression analysis was performed. Multi- and univariate statistical analysis was performed to identify differential gene expression profile of tumors from good (0%-30% residual viable tumor [RVT]) and poor (>30% RVT) chemotherapy-responders. RESULTS: Initially, unsupervised multivariate modeling was performed by principal component analysis, which demonstrated a distinct gene expression profile between good- and poor-chemotherapy responders. There were 396 genes that were significantly (p < 0.05) downregulated (200 genes) or upregulated (196 genes) in tumors from good responders compared to poor responders. Further supervised multivariate analysis of significant genes by partial least square (PLS) demonstrated a highly distinct gene expression profile between good- and poor responders. A gene biomarker of panel (IL18, SPA17, CD58, PTTG1, MTBP, ABL1, SFRP1, CHRDL1, IGF1, and CFD) was selected based on PLS model, and univariate regression analysis of individual genes was performed. The identified biomarker panel demonstrated a very high ability to diagnose good-responding PDAC patients (AUROC: 0.977, sensitivity: 82.4%; specificity: 87.0%). CONCLUSION: A distinct tumor biological profile between PDAC patients who either respond or not respond to chemotherapy was identified.

Neutrophil-lymphocyte ratio and platelet-lymphocyte ratio use in detecting bowel ischaemia in adhesional small bowel obstruction.

BACKGROUND: Bowel ischaemia significantly increases morbidity and mortality from adhesional small bowel obstruction. Current biomarkers and clinical parameters have poor predictive value for ischaemia. Our study investigated whether neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) could be used to predict bowel ischaemia in adhesional small bowel obstruction. METHODS: This single-centre retrospective study collected clinical, biochemical and radiological data from patients with adhesional small bowel obstruction between 2017 and 2020 who underwent operative management. The presence or absence of bowel ischaemia/infarction was used to distinguish two populations. Biochemical markers on admission and immediately prior to operation were collected to give platelet-lymphocyte ratio (PLR0 and PLRPRE-OP , respectively) and neutrophil-lymphocyte ratio (NLR0 and NLRPRE-OP , respectively). SAS 9.4 (SAS Institute Inc., Cary, NC) software was used for data analysis with Mann-Whitney U testing for continuous variables and Pearson Chi-square test for categorical variables. Sensitivity and specificity for PLR and NLR were calculated by means of receiver operating characteristic (ROC) curve analysis. RESULTS: Twenty-seven patients had intra-operative bowel ischaemia whilst the remaining 73 had no evidence of bowel ischaemia. Both median PLRPRE-OP and NLRPRE-OP were significantly higher in patients with bowel ischaemia compared to those without (PLRPRE-OP 272 [IQR 224-433] and 231 [IQR 146-295] respectively, P = 0.027; NLRPRE-OP 12.5 [IQR 8.6-21.3] v. 5.5 [IQR 3.5-10.2] respectively, P ≤ 0.001). Area under the receiver operator characteristic curve (AUC) was 0.762 for NLRPRE-OP , with a sensitivity of 85.1% and specificity of 63% for NLR 7.4. CONCLUSION: Raised NLR is predictive of bowel ischaemia in patients with adhesional small bowel obstruction.