Evaluation of the International Study Group of Pancreatic Surgery definition of delayed gastric emptying after pancreatoduodenectomy in a high-volume centre

Intraoperative Endoluminal Pyloromyotomy Versus Stretching of the Pylorus for the Reduction of Delayed Gastric Emptying After Pylorus-Preserving Partial Pancreatoduodenectomy: A Blinded Randomized Controlled Trial (PORRIDGE Study; DRKS00013503)

BACKGROUND

Pylorus-preserving partial pancreatoduodenectomy (ppPD) is a treatment for tumors of the pancreatic head. Delayed gastric emptying (DGE) is one of the most common complications following ppPD. In a retrospective analysis, intraoperative endoluminal pyloromyotomy (PM) was shown to be associated with a reduction in DGE rates.

OBJECTIVE

The aim of this randomized controlled trial was to investigate the effect of intraoperative endoluminal PM on DGE after ppPD.

METHODS

Patients undergoing ppPD were randomized intraoperatively to receive either PM or atraumatic stretching of the pylorus prior to creation of the duodenojejunostomy. The primary endpoint was the rate of DGE within 30 days after surgery.

RESULTS

Sixty-four patients were randomly assigned to the PM group and 64 patients were assigned to the control group. There were no differences between the two groups regarding baseline characteristics. The DGE rate was 59.4% (76/126). In two patients (1.6%) DGE was not assessable. The most common DGE grade was A (51/126, 40.5%), followed by B (20/126, 15.9%) and C (5/126, 4.0%). The rate of DGE was 62.5% in the PM group versus 56.3% in the control group (odds ratio 1.41, 95% confidence interval 0.69-2.90; p = 0.34). The complication rate did not differ between both groups (p = 0.79) and there were no differences in quality of life on postoperative day 30.

CONCLUSIONS

Intraoperative endoluminal PM did not reduce the rate or severity of DGE after ppPD compared with atraumatic stretching of the pylorus.

Perioperative nutritional practices and associations with delayed gastric emptying in patients undergoing a pancreaticoduodenectomy: A retrospective observational study

AIMS

Delayed gastric emptying is a common complication of a pancreaticoduodenectomy and can adversely impact nutritional status, and potentially clinical outcomes due to delays in nutrition initiation post-operatively. The aim of this study was to explore associations between delayed gastric emptying and patient baseline characteristics, early post-operative nutritional status, post-operative nutritional practices and clinical outcomes in a tertiary Australian hospital.

METHODS

This was a retrospective, observational study of 80 consecutive patients who underwent a pancreaticoduodenectomy between January 2019 and June 2022. Delayed gastric emptying was classified according to the International Study Group of Pancreatic Surgery definition. Continuous variables were compared using the independent t test, and categorical variables were compared using chi-squared or Fisher's exact test. Significant variables were included in a multivariable model.

RESULTS

The incidence of delayed gastric emptying within this cohort was 45% (36/80) and was higher in males compared to females (p = 0.025). Early post-operative nutritional status was not significantly associated with delayed gastric emptying (p = 0.124). Patients with delayed gastric emptying had a higher incidence of post-operative pancreatic fistula (p = 0.03) and Clavien-Dindo complications ≥3 (p = 0.011). Delayed gastric emptying was associated with greater usage of enteral (p < 0.001) and parenteral nutrition (p < 0.001), a longer length of stay (p < 0.001) and increased re-admissions (p = 0.014). Male sex remained significantly associated with delayed gastric emptying following regression analysis.

CONCLUSIONS

Delayed gastric emptying rates were high, associated with greater use of artificial nutrition and worse outcomes in our patient population post-operatively. Early post-operative malnutrition was not significantly associated with delayed gastric emptying.

Primary delayed gastric emptying after pylorus-resecting pancreatoduodenectomy: A matched-pair comparison of Roux-en-Y vs. Billroth-II reconstruction

Background

After pylorus-resecting pancreatoduodenectomy (PrPD), delayed gastric emptying (DGE) might partially be attributed to biliary reflux. We investigated whether the incidence of primary DGE is reduced after Roux-en-Y instead of Billroth-II reconstruction.

Methods

Patients undergoing PrPD from 2016 to 2019 at a high-volume center were identified. Excluding causes of secondary DGE, we matched patients with Roux-en-Y and Billroth-II reconstruction in a 1:2 ratio and compared primary DGE.

Results

In 24 vs. 48 (Roux-en-Y vs. Billroth-II) patients, DGE (grade B/C) incidence (20.8 % vs. 18.8 %; P = 1.000), nasogastric tube requirement (median 2 vs. 2 days; P = 0.844) and time to solid food intake (7 vs. 7 days; P = 0.933) were comparable. Univariable logistic regression showed no association between DGE and Roux-en-Y reconstruction (OR 1.47; P = 0.524), in contrast to age (1.08; P = 0.030) and pancreatic biochemical leak (4.98; P = 0.007).

Conclusions

Primary DGE did not differ between Roux-en-Y and Billroth-II reconstruction after PrPD. Instead, age and postoperative pancreatic biochemical leak were associated with higher DGE risk.

How to Reduce Delayed Gastric Emptying After Pancreatoduodenectomy: A Systematic Literature Review and Meta-Analysis

Introduction

The occurrence of delayed gastric emptying (DGE) following pancreatoduodenectomy is of high clinical relevance. Despite the pivotal nature of this topic, the existing evidence is limited and often conflicting. This meta-analysis aims to assess the impact of various interventions, such as the type of surgical reconstruction (specifically pylorus resection or preservation), enhanced recovery after surgery (ERAS), epidural anesthesia (EA), as well as strategies involving nasogastric decompression on DGE.

Methods

Following the PRISMA guidelines, a systematic search was conducted. Studies that compared patients undergoing pancreatoduodenectomy regarding one of the following interventions were included: pylorus-preserving pancreaticoduodenectomy (ppPD) versus pylorus-resecting pancreaticoduodenectomy (prPD), ERAS versus no ERAS, epidural anesthesia EA versus no EA, nasogastric decompression versus no nasogastric decompression and jejunostomy/nasojejunal feeding tube placement (J/NJF) versus no J/NJF.

Results

The analysis included 5930 patients from 29 studies. Patients undergoing ppPD exhibited a higher incidence of DGE compared with those undergoing prPD (logOR, -0.95; 95% CI = -1.57 to -0.34; P = 0.002). Additionally, patients in the ERAS group showed reduced rates of DGE (logOR, -0.712; 95% CI = -1.242 to -0.183; P = 0.008). Lower rates of DGE were observed in patients without a J/NJF (logOR, -0.618; 95% CI, 0.39-0.84; P < 0.001).

Conclusion

In summary, our meta-analysis reveals that pylorus resection, adherence to ERAS protocols, and the absence of a J/NJF are associated with lower rates of DGE after pancreatoduodenectomy. Although these results are partially based on observational studies, they contribute valuable insights to the current understanding of interventions impacting DGE in these complex procedures.

Predictive Factors for Delayed Gastric Emptying After Pancreatoduodenectomy: A Swedish National Registry-Based Study

BACKGROUND

Delayed gastric emptying (DGE) is a common complication after pancreatoduodenectomy (PD). DGE causes prolonged hospital stay and a decrease in quality of life. This study analyzes predictive factors for development of DGE after PD, also in the absence of surgical complications.

METHOD

Data from the Swedish National Pancreatic Cancer Registry for patients undergoing standard and pylorus preserving open PD from January 2010 until June 30, 2018, were collected. Data were analyzed in two groups, no DGE and DGE. A subgroup of patients with DGE but without surgical complications was compared to patients without DGE or any other surgical complication.

RESULTS

In total, 2503 patients were included, of which 470 (19%) had DGE. In the DGE group, 238 had other coexisting surgical complications and 232 had not. Postoperative pancreatic fistula (OR = 4.22, p < 0.001), surgical infection (OR = 1.44, p = 0.013), heart disease (OR = 1.32, p = 0.023) and medical complications (OR = 1.35, p = 0.025) increased the risk for DGE. A standard PD compared with pylorus preserving resection (OR = 1.69, p = 0.001) and a reconstruction with a pancreaticojejunostomy compared with a pancreaticogastrostomy (OR = 1.83, p < 0.001) increased the risk. For patients without surgical complications, a standard PD and reconstruction with pancreaticojejunostomy still increased the risk for DGE.

CONCLUSION

DGE is more common after standard PD compared to pylorus preserving PD and after reconstruction with PJ compared to PG in this national cohort, both in the presence of other surgical complications as well as in the absence of other complications.

Functional sequelae after pancreatic resection for cancer

The morbidity and mortality of pancreatic cancer surgery has seen substantial improvement due to the standardization of surgical techniques, the optimization of perioperative multidisciplinary management and the organization of specialized care systems. The identification and treatment of postoperative functional and nutritional sequelae have thereby become major issues in patients who undergo pancreatic surgery. This review addresses the functional sequelae of pancreatic resection for cancerous and pre-cancerous lesions (excluding chronic pancreatitis). Its aim is to specify the prevalence and severity of sequelae according to the type of pancreatic resection and to document, where appropriate, the therapeutic management. Exocrine pancreatic insufficiency (ExPI) is observed in nearly one out of three patients at one year after surgery, and endocrine pancreatic insufficiency (EnPI) is present in one out of five patients after pancreatoduodenectomy (PD) and one out of three patients after distal pancreatectomy (DP). In addition, digestive functional disorders may appear, such as delayed gastric emptying (DGE), which affects 10 to 45% of patients after PD and nearly 8% after DP. Beyond these functional sequelae, pancreatic surgery can also induce nutritional and vitamin deficiencies secondary to a lack of uptake for certain vitamins or to the loss of absorption site in the duodenum. In addition to the treatment of ExPI with oral pancreatic enzymes, nutritional management is based on a high-calorie, high-protein diet with normal lipid intake in frequent small feedings, combined with vitamin supplementation adapted to monitored deficiencies. Better knowledge of the functional consequences of pancreatic cancer surgery can improve the overall management of patients.

Prevention of delayed gastric emptying after right colectomy with extended lymphadenectomy: A randomized controlled trial

BACKGROUND

Delayed gastric emptying sometimes occurs after right colectomy with extended lymphadenectomy. The aim of this randomized controlled trial is to evaluate the effect on delayed gastric emptying after performing a fixation of the stomach to the retrogastric tissue to return the stomach to a physiological position after right colectomy with lymphadenectomy, including gastrocolic lymph nodes dissection for proximal transverse colon cancer.

METHODS

From January 2015 to December 2020, patients undergoing right colectomy with extensive lymphadenectomy for proximal transverse colon cancer were randomly assigned to either the gastropexy group or the conventional group. In the gastropexy group, the posterior wall of the stomach, at the level of the antrum, was sutured to the retrogastric tissue to prevent the abnormal shape that the gastric antrum acquires together with the duodeno-pancreatic complex, the shape that leads to an obstruction of the antrum region and to the delay in emptying the gastric contents.

RESULTS

Mean age, sex, comorbidities, and right colectomy procedures were similar in the 2 groups. Delayed gastric emptying developed in twelve patients in the conventional group (38.7%) versus 4 patients (12.1%) in the gastropexy group (P = .014). The total number of complications was higher in the conventional group (14 complications) than in the gastropexy group (7 complications). According to univariate analysis, gastropexy significantly lowered the risk of delayed gastric emptying (P = .014). Overall morbidity was 9.7% in the conventional group versus none in the gastropexy group. Postoperative hospitalization was longer in the conventional group (7.61 ± 3.26 days) than in the gastropexy group (6.24 ± 1.3 days; P = .006).

CONCLUSION

Gastropexy decreases the occurrence of delayed gastric emptying after right colectomy with extended lymphadenectomy for proximal transverse colon cancer.

Machine learning versus logistic regression for the prediction of complications after pancreatoduodenectomy

BACKGROUND

Machine learning is increasingly advocated to develop prediction models for postoperative complications. It is, however, unclear if machine learning is superior to logistic regression when using structured clinical data. Postoperative pancreatic fistula and delayed gastric emptying are the two most common complications with the biggest impact on patient condition and length of hospital stay after pancreatoduodenectomy. This study aimed to compare the performance of machine learning and logistic regression in predicting pancreatic fistula and delayed gastric emptying after pancreatoduodenectomy.

METHODS

This retrospective observational study used nationwide data from 16 centers in the Dutch Pancreatic Cancer Audit between January 2014 and January 2021. The area under the curve of a machine learning and logistic regression model for clinically relevant postoperative pancreatic fistula and delayed gastric emptying were compared.

RESULTS

Overall, 799 (16.3%) patients developed a postoperative pancreatic fistula, and 943 developed (19.2%) delayed gastric emptying. For postoperative pancreatic fistula, the area under the curve of the machine learning model was 0.74, and the area under the curve of the logistic regression model was 0.73. For delayed gastric emptying, the area under the curve of the machine learning model and logistic regression was 0.59.

CONCLUSION

Machine learning did not outperform logistic regression modeling in predicting postoperative complications after pancreatoduodenectomy.

A prediction nomogram for postoperative gastroparesis syndrome in right colon cancer: a retrospective study

PURPOSE

To investigate the high-risk factors for postoperative gastroparesis syndrome (PGS) in right colon cancer and to build a prediction nomogram for personalized prediction of PGS.

METHODS

Our study retrospectively analyzed 361 patients with right colon cancer who underwent right hemicolectomy at The First Hospital of Putian City in Fujian Province, China and who were hospitalized between January 2012 and July 2022. Multivariate logistic regression was used to determine the independent risk factors for PGS and to establish a nomogram model. Furthermore, discrimination, calibration, and clinical benefits were used to evaluate the model.

RESULTS

The multivariate logistic regression revealed that dissection of the subpyloric lymph nodes (No. 206 lymph node) (OR 5.242, P = 0.005), preoperative fasting blood glucose level (OR 3.708, P = 0.024), preoperative albumin level (OR 3.503, P = 0.020), and total operative time (OR 4.648, P = 0.014) were independent risk factors for PGS. Based on the above four factors, the area under the ROC curve (AUC) and C-index of the nomogram were 0.831. The prediction nomogram's calibration curve was closer to the ideal diagonal, and the Hosmer‒Lemeshow test indicated that the nomogram fit well (P = 0.399). Moreover, the decision curve analysis revealed that the model can present better clinical benefits when the threshold probability was between 1 and 28%, and the internal validation verified the dependability of the model (C-index = 0.948).

CONCLUSIONS

A risk prediction nomogram based on perioperative factors provided the physician with a simple, visual, and efficient tool for the prediction and management of PGS in right colon cancer.

Delayed gastric emptying after aggressive surgery for retroperitoneal sarcoma - Incidence, characteristics, and risk factors

Delayed gastric emptying (DGE) after aggressive resection of retroperitoneal sarcoma (RPS) has rarely been described. This study aimed to determine the incidence and characteristics of DGE after surgery for RPS and explore its potential risk factors. Patients with RPS who had undergone surgery between January 2010 and February 2021 were retrospectively analyzed. DGE was defined and graded according to the International Study Group of Pancreatic Surgery classification and classified as primary or secondary to other complications. Patients with clinically relevant DGE (crDGE, grade B+C) were compared to those with no or mild DGE (grade A). Multivariate logistic regression analysis of clinicopathological and surgical parameters was performed to identify risk factors for crDGE. Of the 239 patients studied, 69 (28.9%) had experienced DGE and 54 (22.6%) had experienced crDGE. Patients with primary and secondary DGE accounted approximately half and half. The most common concurrent complications included abdominal infection, postoperative pancreatic fistula, and abdominal bleeding. Patients with crDGE were more likely to have multifocal tumors and the liposarcoma subtype, with a larger tumor size, longer operating time, more resected organs, and a history of combined resection of the stomach, pancreas, small intestine, and/or colon. In multivariate analysis, the tumor size, operating time, and combined pancreatic resection were independent risk factors for crDGE. In conclusion, the current results indicated that approximately one-fourth of patients experienced DGE after aggressive surgery for RPS and that DGE was primary or secondary to other underlying conditions. A large tumor involving long, difficult surgery and combined pancreatic resection highly predicted the incidence of crDGE. The prevention and management of DGE remain challenging.

Impact of Early Enteral Nutrition on Delayed Gastric Emptying and Nutritional Status After Pancreaticoduodenectomy

BACKGROUND

Although early enteral nutrition (EEN) is an accepted practice after pancreaticoduodenectomy (PD), the impact of EEN on postoperative complications or nutritional status remains unclear. We aimed to investigate the impact of EEN on delayed gastric emptying (DGE) and nutritional status after PD.

METHODS

A total of 143 patients underwent PD between January 2012 and September 2020. We excluded patients who underwent a two-stage pancreatojejunostomy, in whom the enteral tube was accidentally pulled out, or with insufficient information in their medical records. The incidence of postoperative complications was compared between patients who received EEN (EEN group, n = 21) and those who did not (control group, n = 21) after propensity score matching. Univariate and multivariate analyses were performed to identify the risk factors affecting the incidence of these complications. Nutritional status was assessed at postoperative months 1, 3, and 6.

RESULTS

The incidence of grade B/C DGE in the EEN group was significantly lower than that in the control group (4.8% vs. 28.6%, p = 0.03). There was no significant difference in overall morbidity, incidence of any other postoperative complications, or all-grade DGE. In multivariate analysis, EEN was associated with a reduction in the incidence of grade B/C DGE (p < 0.01). In the analysis of nutritional status, EEN was significantly associated with better nutritional status at postoperative month 1.

CONCLUSION

EEN can lead to a lower clinically relevant DGE rate and better nutritional status in the early postoperative period in patients undergoing PD.

Delayed Gastric Emptying and Gastric Remnant Function After Pancreaticoduodenectomy: A Systematic Review of Objective Assessment Modalities

BACKGROUND

Delayed gastric emptying (DGE) is a frequent complication after pancreaticoduodenectomy (PD). The diagnosis of DGE is based on International Study Group for Pancreatic Surgery (ISGPS) clinical criteria and objective assessments of DGE are infrequently used. The present literature review aimed to identify objective measures of DGE following PD and determine whether these measures correlate with the clinical definition of DGE.

METHODS

A systematic search was performed using the MEDLINE Ovid, EMBASE, Google Scholar and CINAHL databases for studies including pancreatic surgery, delayed gastric emptying and gastric motility until June 2022. The primary outcome was modalities undertaken for the objective measurement of DGE following PD and correlation between objective measurements and clinical diagnosis of DGE. Relevant risk of bias analysis was performed.

RESULTS

The search revealed 4881 records, of which 46 studies were included in the final analysis. There were four objective modalities of DGE assessment including gastric scintigraphy (n = 28), acetaminophen/paracetamol absorption test (n = 10), fluoroscopy (n = 6) and the ¹³C-acetate breath test (n = 3). Protocols were inconsistent, and reported correlations between clinical and objective measures of DGE were variable; however, amongst these measures, at least one study directly or indirectly inferred a correlation, with the greatest evidence accumulated for gastric scintigraphy.

CONCLUSION

Several objective modalities to assess DGE following PD have been identified and evaluated, however are infrequently used. Substantial variability exists in the literature regarding indications and interpretation of these tests, and there is a need for a real-time objective modality which correlates with ISGPS DGE definition after PD.

Delayed Gastric Emptying Does Not Influence Cancer-Specific Survival after Pancreatoduodenectomy for Pancreatic Ductal Adenocarcinoma

Background: Delayed gastric emptying (DGE) remains the most frequent complication following pancreatoduodenectomy (PD). The present study investigates the influence of delayed gastric emptying on cancer-specific survival after PD. Methods: We included 267 patients who underwent PD between 2014 and 2021. They were analyzed regarding demographic factors, pre- and perioperative characteristics, surgical complications, and long-term survival. Results: Patients with a higher Charlson Comorbidity Index (CCI) or pre-existing pulmonary disease suffered significantly more from DGE. When experiencing PPH, a prolonged hospital stay, or major overall complications (Clavien-Dindo °III-V) were more common in the DGE group. Tumor size over 3 cm negatively affected survival. Conclusions: DGE has no influence on long-term survival in PDAC patients, although it prolongs hospital stay.

Obesity Does Not Influence Delayed Gastric Emptying Following Pancreatoduodenectomy

Background: The data about obesity on postoperative outcome after pancreatoduodenectomy (PD) are inconsistent, specifically in relation to gastric motility and delayed gastric emptying (DGE). Methods: Two hundred and eleven patients were included in the study and patients were retrospectively analyzed in respect to pre-existing obesity (obese patients having a body mass index (BMI) ≥ 30 kg/m2 vs. non-obese patients having a BMI < 30 kg/m2, n = 34, 16% vs. n = 177, 84%) in relation to demographic factors, comorbidities, intraoperative characteristics, mortality and postoperative complications with special emphasis on DGE. Results: Obese patients were more likely to develop clinically relevant pancreatic fistula grade B/C (p = 0.008) and intraabdominal abscess formations (p = 0.017). However, clinically relevant DGE grade B/C did not differ (p = 0.231) and, specifically, first day of solid food intake (p = 0.195), duration of intraoperative administered nasogastric tube (NGT) (p = 0.708), rate of re-insertion of NGT (0.123), total length of NGT (p = 0.471) or the need for parenteral nutrition (p = 0.815) were equally distributed. Moreover, mortality (p = 1.000) did not differ between the two groups. Conclusions: Obese patients do not show a higher mortality rate and are not at higher risk to develop DGE. We thus show that in our study, PD is feasible in the obese patient in regard to postoperative outcome with special emphasis on DGE.

Intraoperative endoluminal pyloromyotomy for reduction of delayed gastric emptying after pylorus preserving partial pancreaticoduodenectomy (PORRIDGE trial): study protocol for a randomised controlled trial

Background

Pylorus-preserving pancreaticoduodenectomy (ppPD) is a standard surgical procedure for the treatment of resectable neoplasms of the periampullary region. One of the most common postoperative complications after ppPD is delayed gastric emptying (DGE) which reduces quality of life, prevents a timely return to a solid oral diet and prolongs the length of hospital stay. In a retrospective analysis, intraoperative endoluminal pyloromyotomy was associated with a reduced rate of DGE. The aim of this study is to investigate the effect of intraoperative endoluminal pyloromyotomy on postoperative DGE after ppPD in a randomised and controlled setting.

Methods

This randomised trial features parallel group design with a 1:1 allocation ratio and a superiority hypothesis. Patients with a minimum age of 18 years and an indication for ppPD are eligible to participate in this study and will be randomised intraoperatively to receive either endoluminal pyloromyotomy or atraumatic stretching of the pylorus. The sample size calculation (n=64 per study arm) is based on retrospective data. The primary endpoint is the rate of DGE within 30 days. Secondary endpoints are quality of life, operation time, estimated blood loss, length of hospital stay, morbidity and mortality.

Discussion

DGE after ppPD is a common complication with an incomplete understood aetiology. Prevention of DGE could improve outcomes and enhance quality of life after one of the most common procedures in pancreatic surgery. This trial will expand the existing evidence on intraoperative pyloromyotomy, and the results will provide additional data on a simple surgical technique that could reduce the incidence of postoperative DGE.

Trial registration

German Clinical Trials RegisterDRKS00013503. Registered on 27 December 2017.

The PrEDICT-DGE score as a simple preoperative screening tool identifies patients at increased risk for delayed gastric emptying after pancreaticoduodenectomy

BACKGROUND

Morbidity after Pancreaticoduodenectomy (PD) has remained unchanged over the past decade. Delayed Gastric Emptying (DGE) is a major contributor with significant impact on healthcare-costs, quality of life and, for malignancies, even survival. We sought to develop a scoring system to aid in easy preoperative identification of patients at risk for DGE.

METHODS

The ACS-NSQIP dataset from 2014 to 2018 was queried for patients undergoing PD with Whipple or pylorus preserving reconstruction. 15,154 patients were analyzed using multivariable logistic regression to identify risk factors for DGE, which were incorporated into a prediction model. Subgroup analysis of patients without SSI or fistula (primary DGE) was performed.

RESULTS

We identified 9 factors independently associated with DGE to compile the PrEDICT-DGE score: Procedures (Concurrent adhesiolysis, feeding jejunostomy, vascular reconstruction with vein graft), Elderly (Age>70), Ductal stent (Lack of biliary stent), Invagination (Pancreatic reconstruction technique), COPD, Tobacco use, Disease, systemic (ASA>2), Gender (Male) and Erythrocytes (preoperative RBC-transfusion). PrEDICT-DGE scoring strongly correlated with actual DGE rates (R² = 0.95) and predicted patients at low, intermediate, and high risk. Subgroup analysis of patients with primary DGE, retained all predictive factors, except for age>70 (p = 0.07) and ASA(p = 0.30).

CONCLUSION

PrEDICT-DGE scoring accurately identifies patients at high risk for DGE and can help guide perioperative management.

Impact of routine nasogastric decompression versus no nasogastric decompression after pancreaticoduodenectomy on perioperative outcomes: meta-analysis

Background

Consensus on the use of nasogastric decompression (NGD) after pancreaticoduodenectomy (PD) is lacking. This meta-analysis reviewed current evidence on the impact of routine NGD versus no NGD after PD on perioperative outcomes.

Methods

PubMed, Medline, Scopus, Embase and Cochrane databases were searched for studies reporting on the role of NGD after PD on perioperative outcomes. Data up to January 2021were retrieved and analysed.

Results

Eight studies were included, with a total of 1301 patients enrolled, of whom 668 had routine NGD. Routine NGD was associated with a higher incidence of overall delayed gastric emptying (DGE) (odds ratio (OR) 2.51, 95 per cent c.i. 1.12 to 5.63, I² = 83 per cent; P = 0.03) and clinically relevant DGE (OR 3.64, 95 per cent c.i. 1.83 to 7.25, I² = 54 per cent; P < 0.01), a higher rate of Clavien–Dindo grade II or higher complications (OR 3.12, 95 per cent c.i. 1.05 to 9.28, I² = 88 per cent; P = 0.04) and increased length of hospital stay (mean difference 2.67, 95 per cent c.i. 0.60 to 4.75, I² = 97 per cent; P = 0.02). There were no significant differences in overall complications (OR 1.07, 95 per cent c.i. 0.79 to 1.46, I² = 0 per cent; P = 0.66) or postoperative pancreatic fistula (OR 1.21, 95 per cent c.i. 0.86 to 1.72, I² = 0 per cent; P = 0.28) between patients with or those without routine NGD.

Conclusion

Routine NGD was associated with increased rates of DGE, major complications and longer length of stay after PD.

Gastrocolic ligament lymph-node dissection may increase the incidence of delayed gastric emptying after colon cancer surgery with D3 lymphadenectomy

PURPOSE

Delayed gastric emptying (DGE) is associated with prolonged hospital stay and higher healthcare costs. This study aimed to investigate the risk factors for DGE after D3 radical resection for colon cancer and to build a nomogram for this complication.

METHODS

We analyzed, retrospectively, 1160 consecutive patients who underwent surgery with D3 lymphadenectomy for colon cancer between January, 2012 and June, 2018. A multivariate logistic regression analysis was used to identify the risk factors for DGE and to build a DGE nomogram model.

RESULTS

There were ten, six and four patients with DGE classified as grades A, B and C, respectively, representing a DGE rate of 1.7%. Multivariate analysis revealed that age (P = 0.001), dissection of the gastrocolic ligament lymph nodes (GCLNs) (P = 0.001), surgical duration (P = 0.017) and preoperative hemoglobin level (P = 0.016) were independent risk factors, and were included to build a predictive model for DGE. The therapeutic index of GCLN dissection was approximately half that of D3 lymphadenectomy (2.9 vs. 5.6).

CONCLUSIONS

DGE is more likely to develop in patients aged > 75 years, those with a preoperative hemoglobin < 90 g/L, those with a surgical duration > 210 min, and those who undergo GCLN dissection. The nomogram may facilitate the stratification of patients at risk for DGE following D3 lymphadenectomy for colon cancer. Assessing long-term outcomes will help to evaluate the survival benefit of GCLN dissection in the future, to avoid unnecessary dissection and reduce the incidence of DGE.

Impact of gastric resection and enteric anastomotic configuration on delayed gastric emptying after pancreaticoduodenectomy: a network meta-analysis of randomized trials

INTRODUCTION

Delayed gastric emptying (DGE) is frequent after pancreaticoduodenectomy (PD). Several RCTs have explored operative strategies to minimize DGE, however, the optimal combination of gastric resection approach, anastomotic route, configuration and the use of enteroenterostomy remains unclear.

METHODS

MEDLINE, Embase and CENTRAL databases were systematically searched for RCTs comparing gastric resection (classic Whipple, pylorus-resecting, pylorus-preserving), anastomotic route (antecolic, retrocolic), configuration (loop gastroenterostomy/Billroth II, Roux-en-Y), and use of enteroenterostomy (Braun). A random-effects, Bayesian network meta-analysis with non-informative priors was conducted to determine the optimal combination of approaches to PD for minimizing DGE.

RESULTS

Twenty-four RCTs, including 2526 patients and 14 approaches were included. There was some heterogeneity, although inconsistency was low. The overall incidence of DGE was 25.6 per cent (647 patients). Pylorus-resecting, antecolic, Billroth II with Braun enteroenterostomy was associated with the lowest rates of DGE and ranked the best in 35 per cent of comparisons. Classic Whipple, retrocolic, Billroth II with Braun ranked the worst for DGE in 32 per cent of comparisons. Pairwise meta-analysis of retrocolic versus antecolic route for gastrojejunostomy found increased risk of DGE with the retrocolic route (odds ratio 2.10, 95 per cent credibility interval (cr.i.) 0.92 to 4.70). Pairwise meta-analysis of enteroenterostomy found a trend towards lower DGE rates when this was used (odds ratio 1.90, 95 per cent cr.i. 0.92 to 3.90). Having a Braun enteroenterostomy ranked the best in 96 per cent of comparisons.

CONCLUSION

Based on existing RCT evidence, a pylorus-resecting, antecolic, Billroth II with Braun enteroenterostomy seems to be associated with the lowest rates of DGE.

PREREGISTRATION

PROSPERO submitted 23 December 2020. CRD42021227637.

Previous upper abdominal surgery is a risk factor for nasogastric tube reinsertion after pancreaticoduodenectomy

BACKGROUND

Pancreaticoduodenectomy without subsequent nasogastric tube management has not been widely adopted due to delayed gastric emptying, the specific and frequent morbidity associated with this surgical procedure. We assessed the feasibility of pancreaticoduodenectomy without use of nasogastric tubes and the risk factors for subsequent nasogastric tube reinsertion.

METHODS

We retrospectively reviewed 465 patients who underwent pancreaticoduodenectomy at a single institution between 2010 and 2019. Primary endpoint was the rate of nasogastric tube reinsertion. Logistic regression analysis was used to determine independent risk factors of nasogastric tube reinsertion and delayed gastric emptying.

RESULTS

The rate of nasogastric tube reinsertion was 10.1% (47/465). The rate of delayed gastric emptying was 9.5% (44/465). Logistic regression analysis identified 4 independent risk factors for nasogastric tube reinsertion: male sex (odds ratio = 4.42; 95% confidence interval 1.50-13.0, P = .007), comorbidity of cardiac ischemia (odds ratio = 3.04; 95% confidence interval 1.05-8.79, P = .041), preoperative cholangitis or cholecystitis (odds ratio = 2.21; 95% confidence interval 1.02-4.76, P = .044), and previous upper abdominal surgery (odds ratio = 8.34; 95% confidence interval 3.07-22.7, P < .001). Independent risk factors for delayed gastric emptying were male sex (odds ratio = 3.20; 95% confidence interval 1.11-9.21, P = .031), comorbidity of cardiac ischemia (odds ratio = 3.81; 95% confidence interval 1.34-10.8, P = .012), concomitant organ resection (odds ratio = 3.99; 95% confidence interval 1.10-14.4, P = .035), and previous upper abdominal surgery (odds ratio = 7.21; 95% confidence interval 2.68-19.4, P < .001).

CONCLUSION

Pancreaticoduodenectomy without use of nasogastric tubes is feasible, but patients with previous upper abdominal surgery require careful postoperative nasogastric tube management.

Early Nasojejunal Nutrition Versus Early Oral Feeding in Patients After Pancreaticoduodenectomy: A Randomized Controlled Trial

Objective

The aim of this study was to test the hypothesis that early oral feeding (EOF) is superior to early nasojejunal nutrition (ENN) after pylorus-preserving pancreaticoduodenectomy (PPPD) in terms of delayed gastric emptying (DGE).

Background

DGE is a common complication after PPPD. Although EOF after PPPD is recommended by several international guidelines, there is no randomized trial to support this recommendation.

Methods

From September 2016 to December 2017, a total of 120 patients undergoing PPPD were randomized into the ENN, EOF, or saline groups at a 1:1:1 ratio (40 patients in each group). The primary endpoint was the rate of clinically relevant DGE. Secondary endpoints included overall morbidity, postoperative pancreatic fistula, post-pancreatectomy hemorrhage, abdominal infection, length of hospital stay, reoperation rate, and in-hospital mortality.

Results

The baseline characteristics and operative parameters were comparable between the groups. The incidence of clinically relevant DGE varied significantly among the three groups (ENN, 17.5%; EOF, 10.0%; saline, 32.5%; p =0.038). The saline group had a higher clinically relevant DGE rate than the EOF group (p = 0.014). The saline group also had greater overall morbidities than the ENN and EOF groups (p = 0.041 and p = 0.006, respectively). There were no significant differences in other surgical complication rates or postoperative hospital stay. No mortality was observed in any of the groups.

Conclusions

Nutritional support methods were not related to DGE after PPPD. EOF was feasible and safe after PPPD, and additional ENN should not be routinely administered to patients after PPPD.

Clinical Trial Registration

ClinicalTrials.gov, identifier NCT03150615.

Roux-en-Y versus single loop reconstruction in pancreaticoduodenectomy: A systematic review and meta-analysis

BACKGROUND

Post-operative pancreatic fistula (POPF) and delayed gastric emptying (DGE) both remain problematic complications following pancreaticoduodenectomy. This systematic review and meta-analysis evaluates whether Roux-en-Y compared to a single loop reconstruction in pancreaticoduodenectomy significantly reduces rates of these complications.

METHODS

A systematic review and meta-analysis was conducted according to the PRISMA guidelines by screening EMBASE, MEDLINE/PubMed, CENTRAL and bibliographic reference lists for comparative studies meeting the predetermined inclusion criteria. Post-operative outcome measures included: POPF, DGE, bile leak, operating time, blood loss, need for transfusion, wound infection, intra-abdominal collection, post-pancreatectomy haemorrhage, overall morbidity, re-operation, overall mortality, hospital length of stay. Pooled odds ratios or mean differences with 95% confidence intervals were calculated using either fixed- or random-effects models.

RESULTS

Fourteen studies were identified including four randomised controlled trials (RCTs) and 10 observational studies reporting a total of 2,031 patients. Data synthesis showed no statistically significant difference between the two groups in any of the outcome measures except operating time, which was longer in those undergoing Roux-en-Y reconstruction.

DISCUSSION

Roux-en-Y is not superior to single loop reconstruction in pancreaticoduodenectomy but may prolong operating time. Future high-quality randomised studies with appropriate study design and sample size power calculation may be required to further validate this conclusion.

Percutaneous Gastrojejunostomy Tube Insertion in Patients with Surgical Gastrojejunal Anastomoses: Analysis of Success Rates and Durability

Patients with a gastrojejunal anastomosis pose challenging anatomy for percutaneous gastrojejunostomy (GJ)-tube placement. A retrospective review of 24 patients (mean age 67.8 years, 13 males) with GJ anastomoses who underwent attempted GJ tube placement revealed infeasible placement in 6 patients (25%) due to an inadequate window for puncture. When a gastric puncture was achieved, GJ tube insertion was technically successful in 83% (15/18) of attempts, resulting in an overall technical success rate of 63% (15/24). The most common tube-related complication was the migration of the jejunal limb into the stomach, which occurred in 40% (6/15) of successful cases. No major procedure related complications were encountered.

Intraoperative endoluminal pyloromyotomy as a novel approach to reduce delayed gastric emptying after pylorus-preserving pancreaticoduodenectomy-a retrospective study

Background

Delayed gastric emptying (DGE) is one of the most common complications after pylorus-preserving partial pancreaticoduodenectomy (ppPD). The aim of this retrospective study was to assess whether an intraoperative pyloromyotomy during ppPD prior to the creation of duodenojejunostomy reduces DGE.

Methods

Patients who underwent pylorus-preserving pancreaticoduodenectomy between January 2015 and December 2017 were divided into two groups on the basis of whether an intraoperative pyloromyotomy was performed (pyloromyotomy (PM) group) or not (no pyloromyotomy (NP) group). The primary endpoint was DGE according to the ISGPS definition. The confirmatory analysis of the primary endpoint was performed with multivariate analysis.

Results

One hundred and ten patients were included in the statistical analysis. Pyloromyotomy was performed in 44 of 110 (40%) cases. DGE of any grade was present in 62 patients (56.4%). The DGE rate was lower in the PM group (40.9%) compared with the NP group (66.7%), and pyloromyotomy was associated with a reduced risk for DGE in univariate (OR 0.35, 95% CI 0.16–0.76; P = 0.008) and multivariate analyses (OR 0.32, 95% CI 0.13–0.77; P = 0.011). The presence of an intra-abdominal complication was an independent risk factor for DGE in the multivariate analysis (OR 5.54, 95% CI 2.00–15.36; P = 0.001).

Conclusion

Intraoperative endoluminal pyloromyotomy during ppPD was associated with a reduced risk for DGE in this retrospective study. Pyloromyotomy should be considered a simple technique that can potentially reduce DGE rates after ppPD.

Is delayed gastric emptying associated with pylorus ring preservation in patients undergoing pancreaticoduodenectomy?

BACKGROUND/OBJECTIVE

A high incidence of delayed gastric emptying (DGE) is observed in patients undergoing pylorus-preserving pancreaticoduodenectomy (PpPD). However, DGE incidence after pancreaticoduodenectomy varied because of heterogeneity in surgical techniques, number of surgeons, and DGE definition. This study aimed to evaluate the difference in the incidence of DGE following PpPD and pylorus-resecting pancreaticoduodenectomy (PrPD) and to analyze the risk factor of DGE by a single surgeon to determine whether pylorus preservation was the main factor of DGE.

METHODS

This retrospective study included 115 patients who underwent PpPD (with pylorus ring preservation) and PrPD (without pylorus ring preservation) with laparotomy by a single surgeon at a tertiary center.

RESULTS

The overall incidence of DGE was 23.1%. For comparison, 20 patients (39.2%) in the PpPD group and 5 patients (8.8%) in the PrPD group had DGE, showing a significant difference (p < 0.001). On univariate analysis, hypertension, PpPD, operation time, intraoperative bleeding, packed red blood cell transfusion ≥500 mL, and clinically relevant postoperative pancreatic fistula were associated with DGE. Multivariate analysis identified pylorus preservation and clinically relevant postoperative pancreatic fistula as risk factors for DGE.

CONCLUSION

Compared with PpPD, PrPD significantly reduced the incidence of DGE.

Nasogastric Decompression vs No Decompression After Pancreaticoduodenectomy: The Randomized Clinical IPOD Trial

Importance

Although standardization of pancreaticoduodenectomy (PD) has improved postoperative outcomes, morbidity remains high. Fast-track surgery programs appear to improve morbidity, and avoiding nasogastric tube decompression (NGTD), already outdated in most major abdominal surgery, is strongly suggested after PD by fast-track surgery programs but lacks high-level evidence, especially regarding safety.

Objective

To assess in a randomized clinical trial whether the absence of systematic NGTD after PD reduces postoperative complications.

Design, Setting, and Participants

The IPOD study (Impact of the Absence of Nasogastric Decompression After Pancreaticoduodenectomy) was an open-label, prospective, single-center, randomized clinical trial conducted at a high-volume pancreatic surgery university hospital in France. In total, 155 patients who were 18 to 75 years of age and required PD for benign or malignant disease were screened for study eligibility. Key exclusion criteria were previous gastric or esophageal surgery and severe comorbidities. Patients were randomly assigned (1:1) to systematic NGTD or to no nasogastric decompression and were followed up until 90 days after surgery.

Interventions

For patients without NGTD, the NGT was removed immediately after surgery, whereas for patients with NGTD, the NGT was removed 3 to 5 days after surgery.

Main Outcomes and Measures

The primary end point was the occurrence of postoperative complications grade II or higher using the Clavien-Dindo classification. The primary end point and safety were evaluated in the intent-to-treat population.

Results

From January 2016 to August 2018, 125 screened patients were considered eligible for the study, and 111 were randomized to no NGTD (n = 52) or to NGTD (n = 59). No patient was lost to follow-up. The 2 groups had similar patient demographic and clinical characteristics at baseline. The median (interquartile range) age was 63.0 (57.0-66.5) years in the group with NGTD (38 [64.4%] were males) and 64.0 (58.0-68.0) years in the group without NGTD (31 [59.6%] were males). The postoperative complication rates grade II or higher were similar between the 2 groups (risk ratio, 0.99; 95% CI, 0.66-1.47; P > .99). Pulmonary complication rates (risk ratio, 0.59; 95% CI, 0.18-1.95; P = .44) and delayed gastric emptying rates (risk ratio, 1.07; 95% CI, 0.52-2.21; P > .99) were not significantly different between the groups. Median (interquartile) length of hospital stay for patients without NGTD was not significantly different compared with those with NGTD (10.0 [9.0-16.3] vs 12.0 [10.0-16.0] days; P = .14).

Conclusions and Relevance

The present study found no significant difference in postoperative complication occurrence of Clavien-Dindo classification grade II or higher between systematic NGTD and no NGTD after PD, suggesting that avoiding systematic nasogastric decompression is safe for this indication.

Trial Registration

ClinicalTrials.gov Identifier: NCT02594956.

Delayed gastric emptying following pancreatoduodenectomy: a Roux-en-Y gastrojejunostomy vs Billroth II gastrojejunostomy randomized study

INTRODUCTION

delayed gastric emptying (DGE) is the most common complication after pancreaticoduodenectomy (PD) and it occurs in 50% of cases.

OBJECTIVES

the endpoint was to determine if there were any differences in the incidence of DGE between Roux-en-Y gastrojejunostomy (ReY) and Billroth II gastrojejunostomy (BII) in PD with pancreaticogastrostomy (PG).

METHODS

this was a case-control prospective randomized study of all PD cases between 2013 and 2016. Sixty-four patients were included, 32 in each group. An intention-to-treat statistical analysis was performed.

RESULTS

no significant differences were found with regard to morbidity and mortality or hospital stay. DGE was present in 25% of the patients in the BII group in comparison to 15.6% in the ReY group, which was not statistically significant (p = 0.35). There was a higher percentage of patients with primary DGE in the BII group, 12.5% versus 6.2%, but this was not statistically significant (p = 0.53). No difference in DGE severity was observed. Male gender (OR 8.38 [1.1; 129]), abdominal complications (OR 15 [1.7; 396.9]), pre-operative malnutrition (OR 99.7 [3.3, 11,126]) and hemorrhage (OR 9.4 [1.37, 107.94]) were the main risk factors for DGE according to the multivariate analysis.

CONCLUSIONS

there were no significant differences in the incidence or severity of DGE between BII or ReY after PD with PG.

Use of Video Review to Investigate Technical Factors That May Be Associated With Delayed Gastric Emptying After Pancreaticoduodenectomy

Importance

Technical proficiency at robotic pancreaticoduodenectomy (RPD) and video assessment are promising tools for understanding postoperative outcomes. Delayed gastric emptying (DGE) remains a major driver of cost and morbidity after pancreaticoduodenectomy.

Objective

To determine if technical variables during RPD are associated with postoperative DGE.

Design, Setting, and Participants

A retrospective study was conducted of technical assessment performed in all available videos (n = 192) of consecutive RPDs performed at a single academic institution from October 3, 2008, through September 27, 2016.

Exposures

Video review of gastrojejunal anastomosis during RPD.

Main Outcomes and Measures

Delayed gastric emptying was classified according to International Study Group of Pancreatic Surgery criteria. Video analysis reviewed technical variables specific in the construction of the gastrojejunal anastomosis. Using multivariate analysis, DGE was correlated with known patient variables and technical variables, individually and combined.

Results

Of 410 RPDs performed, video was available for 192 RPDs (80 women and 112 men; mean [SD] age, 65.7 [11.1] years). Delayed gastric emptying occurred in 41 patients (21.4%; grade A, 15; grade B, 14; and grade C, 12). Patient variables contributing to DGE on multivariate analysis were advanced age (odds ratio [OR] 1.11; 95% CI, 1.05-1.16; P < .001), small pancreatic duct size (OR, 0.84; 95% CI, 0.72-0.98; P = .03), and postoperative pseudoaneurysm (OR, 17.29; 95% CI, 2.34-127.78; P = .005). However, technical variables contributing to decreased DGE on multivariate analysis included the flow angle (within 30° of vertical) between the stomach and efferent jejunal limb (OR, 0.25; 95% CI, 0.08-0.79; P = .02), greater length of the gastrojejunal anastomosis (OR, 0.40; 95% CI, 0.20-0.77; P = .006), and a robotic-sewn anastomosis (robotic suture vs stapler: OR, 0.30; 95% CI, 0.09-0.95; P = .04).

Conclusions and Relevance

This study examines modifiable technical factors through the use of review of video obtained at the time of operation and suggests ways by which the surgical construction of the gastrojejunal anastomosis during RPD may reduce the incidence of DGE as a framework for prospective quality improvement.

Pylorus Resection Does Not Reduce Delayed Gastric Emptying After Partial Pancreatoduodenectomy: A Blinded Randomized Controlled Trial (PROPP Study, DRKS00004191)

OBJECTIVES

The aim of this study was to investigate the effect of pylorus resection on postoperative delayed gastric emptying (DGE) after partial pancreatoduodenectomy (PD).

BACKGROUND

PD is the standard treatment for tumors of the pancreatic head. Preservation of the pylorus has been widely accepted as standard procedure. DGE is a common complication causing impaired oral intake, prolonged hospital stay, and postponed further treatment. Recently, pylorus resection has been shown to reduce DGE.

METHODS

Patients undergoing PD for any indication at the University of Heidelberg were randomized to either PD with pylorus preservation (PP) or PD with pylorus resection and complete stomach preservation (PR). The primary endpoint was DGE within 30 days according to the International Study Group of Pancreatic Surgery definition.

RESULTS

Ninety-five patients were randomized to PP and 93 patients to PR. There were no baseline imbalances between the groups. Overall, 53 of 188 patients (28.2%) developed a DGE (grade: A 15.5%; B 8.8%; C 3.3%). In the PP group 24 of 95 patients (25.3%) and in the PR group 29 of 93 patients (31.2%) developed DGE (odds ratio 1.534, 95% confidence interval 0.788 to 2.987; P = 0.208). Higher BMI, indigestion, and intraabdominal major complications were significant risk factors for DGE.

CONCLUSIONS

In this randomized controlled trial, pylorus resection during PD did not reduce the incidence or severity of DGE. The development of DGE seems to be multifactorial rather than attributable to pyloric dysfunction alone. Pylorus preservation should therefore remain the standard of care in PD.

TRIAL REGISTRATION

German Clinical Trials Register DRKS00004191.

Antecolic reconstruction is associated with a lower incidence of delayed gastric emptying compared to retrocolic technique after Whipple or pylorus-preserving pancreaticoduodenectomy

BACKGROUND

The aim of present study is to investigate the relationship between the antecolic (AC) route of gastrojejunostomy (GJ) after pancreaticoduodenectomy (PD) or duodenojejunostomy (DJ) reconstruction after pylorus-preserving pancreaticoduodenectomy (PPPD), and the incidence of delayed gastric emptying (DGE).

METHODS

An electronic search of 4 databases to identify all articles comparing AC and retrocolic (RC) reconstruction after PD or PPPD was performed.

RESULTS

Fifteen studies involving 2270 patients were included for final pooled analysis. The overall incidence of DGE was 27.2%. Meta-analysis results showed AC group had lower incidence of DGE (odds ratio, 0.29; 95% confidence interval [CI], 0.16-0.52, P < .0001) and shorter hospital length of stay (weight mean difference, -3.29; 95% CI, -5.2 to -1.39, P = .0007). Days until to liquid and solid diet in the AC group were also significantly earlier than that in the RC group (P = .0006 and P < .0001). There was no difference in operative time, incidence of pancreatic fistula and bile leakage, and mortality, respectively.

CONCLUSIONS

AC route of GJ after PD or DJ after PPPD is associated with a lower incidence of DGE. However, the preferred route for GJ or DJ reconstruction remains to be investigated in well-powered, randomized, controlled trial.

Retrocolic Gastrojejunostomy After Pancreaticoduodenectomy: A Satisfactory Delayed Gastric-Emptying Rate

OBJECTIVES

Delayed gastric emptying (DGE) is a critical complication after pancreaticoduodenectomy (PD). Antecolic gastrojejunostomy has long been adopted as standard procedure because it is thought to reduce DGE. However, we have used retrocolic gastrojejunostomy (retro-GJ) for more than 10 years and have not observed high DGE rates. We aimed to clarify whether our retro-GJ approach produced comparable outcomes in preventing DGE.

METHODS

A total of 211 patients who underwent pylorus-resecting PD with retro-GJ at our institution between 2005 and 2016 were retrospectively analyzed. The incidence rate of DGE and the length of postoperative hospital stay were assessed.

RESULTS

The overall incidence of DGE with our retro-GJ procedure was 13% (n = 28), and the rate of clinically relevant DGE (grade B or C based on the International Study Group of Pancreatic Surgery criteria) was 4% (n = 8). The median postoperative hospital stay was 17 days (interquartile range, 13-25 days). Major complications (Clavien-Dindo grade ≥III) occurred in 37% (n = 79) of patients and were not associated with the occurrence of clinically relevant DGE (P = 0.47).

CONCLUSIONS

Our retro-GJ approach after PD with gastrojejunostomy, which involves careful positioning at the left-sided inframesocolic point, satisfactorily prevents DGE.

PANCREATICODUODENECTOMY: IMPACT OF THE TECHNIQUE ON OPERATIVE OUTCOMES AND SURGICAL MORTALITY

BACKGROUND

Pancreaticoduodenectomy (PD) is a procedure associated with significant morbidity and mortality. Initially described as gastropancreaticoduodenectomy (GPD), the possibility of preservation of the gastric antrum and pylorus was described in the 1970s.

AIM

To evaluate the mortality and operative variables of PD with or without pyloric preservation and to correlate them with the adopted technique and surgical indication.

METHOD

Retrospective cohort on data analysis of medical records of individuals who underwent PD from 2012 through 2017. Demographic, anthropometric and operative variables were analyzed and correlated with the adopted technique (GPD vs. PD) and the surgical indication.

RESULTS

Of the 87 individuals evaluated, 38 (43.7%) underwent GPD and 49 (53.3%) were submitted to PD. The frequency of GPD (62.5%) was significantly higher among patients with pancreatic neoplasia (p=0.04). The hospital stay was significantly shorter among the individuals submitted to resection due to neoplasias of less aggressive behavior (p=0.04). Surgical mortality was 10.3%, with no difference between GPD and PD. Mortality was significantly higher among individuals undergoing resection for chronic pancreatitis (p=0.001).

CONCLUSION

There were no differences in mortality, surgical time, bleeding or hospitalization time between GPD and PD. Pancreas head neoplasm was associated with a higher indication of GPD. Resection of less aggressive neoplasms was associated with lower morbidity and mortality.

Monitoring gastric myoelectric activity after pancreaticoduodenectomy for diet "readiness"

Postoperative delayed gastric emptying (DGE) is a frustrating complication of pancreaticoduodenectomy (PD). We studied whether monitoring of postoperative gastric motor activity using a novel wireless patch system can identify patients at risk for DGE. Patients ( n = 81) were prospectively studied since 2016; 75 patients total were analyzed for this study. After PD, battery-operated wireless patches (G-Tech Medical) that acquire gastrointestinal myoelectrical signals are placed on the abdomen and transmit data by Bluetooth. Patients were divided into early and late groups by diet tolerance of 7 days [enhanced recovery after surgery (ERAS) goal]. Subgroup analysis was done of patients included after ERAS initiation. The early and late groups had 50 and 25 patients, respectively, with a length of stay (LOS) of 7 and 11 days ( P < 0.05). Nasogastric insertion was required in 44% of the late group. Tolerance of food was noted by 6 versus 9 days in the early versus late group ( P < 0.05) with higher cumulative gastric myoelectrical activity. Diminished gastric myoelectrical activity accurately identified delayed tolerance to regular diet in a logistical regression analysis [area under the curve (AUC): 0.81; 95% confidence interval (CI), 0.74-0.92]. The gastric myoelectrical activity also identified a delayed LOS status with an AUC of 0.75 (95% CI, 0.67-0.88). This stomach signal continued to be predictive in 90% of the ERAS cohort, despite earlier oral intake. Measurement of gastric activity after PD can distinguish patients with shorter or longer times to diet. This noninvasive technology provides data to identify patients at risk for DGE and may guide the timing of oral intake by gastric "readiness." NEW & NOTEWORTHY Limited clinical indicators exist after pancreaticoduodenectomy to allow prediction of delayed gastric emptying (DGE). This study introduces a novel, noninvasive, wireless patch system capable of accurately monitoring gastric myoelectric activity after surgery. This system can differentiate patients with longer or shorter times to a regular diet as well as provide objective data to identify patients at risk for DGE. This technology has the potential to individualize feeding regimens based on gastric activity patterns to improve outcomes.

Mortality after pancreaticoduodenectomy: assessing early and late causes of patient death

BACKGROUND

Safety of pancreaticoduodenectomy has improved significantly in the past 3 decades. Current inpatient and 30-d mortality rates are low. However, incidence and causes of 90-d and 1-y mortality are poorly defined and largely unexplored.

METHODS

All patients who had pancreaticoduodenectomy between 2007 and 2016 were included in this single institution, retrospective cohort study. Distributions of pancreaticoduodenectomy-specific morbidity and cause-specific mortality were compared between early (within 90 d) and late (91-365 d) postoperative recovery periods.

RESULTS

A total of 551 pancreaticoduodenectomies were performed during the study period. Of these, 6 (1.1%), 20 (3.6%), and 91 (16.5%) patients died within 30, 90, and 365 d after pancreaticoduodenectomy, respectively. Causes of early and late mortality varied significantly (all P ≤ 0.032). The most common cause of death within 90 d was due to multisystem organ failure from sepsis or aspiration in 9 (45%) patients, followed by post-pancreatectomy hemorrhage in 5 (25%) patients, and cardiopulmonary arrest from myocardial infarction or pulmonary embolus in 3 (15%) patients. In contrast, recurrent cancer was the most common cause of death in 46 (65%) patients during the late postoperative period between 91 and 365 d. Mortality from failure to thrive and debility was similar between early and late postoperative periods (15% versus 19.7%, P = 0.76).

CONCLUSIONS

Most quality improvement initiatives in patients selected for pancreaticoduodenectomy have focused on reduction of technical complications and improvement of early postoperative mortality. Further reduction in postoperative mortality after pancreaticoduodenectomy can be achieved by improving patient selection, mitigating postoperative malnutrition, and optimizing preoperative cancer staging and management strategies.

Health economic implications of complications associated with pancreaticoduodenectomy at a University Hospital: a retrospective cohort cost study

BACKGROUND

A cost analyses of complications following pancreaticoduodenectomy (PD) was performed in a high volume hepato-biliary-pancreatic service. We hypothesised that costs are increased with both severity and number of complications; we investigated the relationship between complications and specific cost centres.

METHODS

100 patients from 2011 to 2016 were included. Data relating to their perioperative course were collected. Complications were documented by the Clavien-Dindo classification and costs were inflated and converted to 2017 USD.

RESULTS

Mean hospital costs in complicated patients more than doubled those of uncomplicated patients ($28 330 vs. $57 150, p < 0.0001). Total hospital costs significantly increased with both severity and number of complications. This cost increase was influenced by medical consult, pathology, pharmacy, radiology, ward, intensive care, and allied health costs, but not operating theatre or anaesthesia costs. Postoperative pancreatic fistula, postoperative haemorrhage, delayed gastric emptying and infection were associated with cost differentials of $65 438, $74 079, $35 620 and $46 316 respectively over uncomplicated patients.

CONCLUSION

The development of complications following PD is common, costly and associated with increased length of stay. Costs increased with greater complication severity, and specific complications. The in-depth breakdown of hospital costs suggests specific targets for cost containment.

The cost of perioperative complications following pancreaticoduodenectomy: A systematic review

BACKGROUND/OBJECTIVES

Pancreaticoduodenectomy (PD), also known as a Whipple procedure, is commonly performed for a variety of benign and malignant tumours, including of the pancreatic head and surrounding structures. PD is associated with low mortality but high morbidity and costs. Our objective was to describe the financial burden of complications following pancreaticoduodenectomy.

METHODS

We searched for articles using the MEDLINE, EMBASE, Cochrane and EconLit databases from the year 2000. Additional studies were identified by searching bibliographies. We included studies reporting on hospital cost or charge of in-hospital complications during the index PD admission. Studies including other surgeries but specifically reporting inpatient complication costs of PD were also included. Any type of PD was included. Data was collected using a data extraction table and a narrative synthesis was performed.

RESULTS

We identified 15 eligible articles. All included articles were retrospective studies. Acceptable evidence for increased cost due to the presence and grade of complication was found. Strong evidence demonstrated the high rate of complications. Weak evidence linked complications with specific constituents of hospital cost. Complication grade was robustly linked with increased length of stay. Not enough evidence was found to demonstrate a link between PD complications and mortality or readmissions.

LIMITATIONS

Included studies were heterogeneous in setting, methodology, costing data, and grading systems.

CONCLUSIONS

The presence and grade of PD complications increase hospital cost across diverse settings. The costing methodology should be transparent and complication grading systems should be consistent in future studies.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO 2017:CRD42017058427.

Perioperative outcome of elderly versus younger patients undergoing major hepatic or pancreatic surgery

Objective

The aim of this study was to determine the safety of elderly cancer patients (≥70 years) undergoing hepatic resection (HR) or pancreaticoduodenectomy (PD) in comparison with younger adults (<70 years).

Methods

A total of 1,012 consecutive patients undergoing HR or PD were included. The incidence and severity of morbidity were documented within 30 days postoperatively and compared between elderly and younger groups. Risk factors associated with postoperative morbidity were investigated by multivariate logistic regression analysis.

Results

Elderly patients (n=111, 11.0%) had more comorbidities and worse preoperative general condition and liver function versus younger patients (n=901, 89.0%), and thus were more likely to develop infectious (eg, systemic sepsis and urinary tract infection, both p<0.01) and technical-associated complications (intraperitoneal bleeding and biliary/pancreatic fistula, p=0.029 and p=0.074, respectively). However, the incidence and severity of complications were comparable between elderly and younger patients in the whole cohort, and also in HR and PD surgery groups separately. Preoperative hemoglobin (odds ratio [OR] 1.4, p=0.007) and intraoperative blood transfusion (OR 1.9, p=0.002), rather than age, were independently associated with postoperative morbidity. Hepatitis (OR 2.9, p=0.001), preoperative hemoglobin (OR 1.6, p=0.036), and pancreatic versus hepatic surgery (OR 2.3, p=0.005) were independently associated with postoperative infectious. For elderly patients only, American Society of Anesthesiologists (ASA) score III (OR 2.1, p=0.033) and intraoperative blood transfusion (OR 3.2, p=0.030) were independently associated with postoperative morbidity.

Conclusion

HR and PD can be safely performed in selected elderly patients versus younger patients. Elderly patients with ASA score III or above should be cautiously selected for major surgeries.

Does Pancreaticogastrostomy Decrease the Occurrence of Delayed Gastric Emptying After Pancreatoduodenectomy?

OBJECTIVES

This study investigates the factors that could influence the development of delayed gastric emptying (DGE) after pancreatoduodenectomy (PD). Delayed gastric emptying is a common complication after PD. The postoperative course is affected by a lengthened hospital stay, a decrease of the patients' quality of life, and a delayed adjuvant treatment.

METHODS

From January 2000 to December 2012, 257 patients underwent PD in the same center. Forty-six variables were retrospectively extracted from medical records. Delayed gastric emptying (grades A, B, and C) was defined by the International Study Group of Pancreatic Surgery classification. Univariate and multivariate analyses were performed to identify factors associated with DGE.

RESULTS

Delayed gastric emptying occurred in 133 patients (51.8%), 89 grade A (66.9%), 27 grade B (20.3%), and 17 grade C (12.8%). Biliary fistula (odds ratio [OR], 8.87; 95% confidence interval [CI], 2.07-37.99, P = 0.003), sepsis (OR, 8.02; 95% CI, 3.22-19.99; P < 0.0001), and intra-abdominal collection (OR, 3.43; 95% CI, 1.06-11.06; P = 0.039) were identified as independent risk factors for DGE, whereas pancreaticogastrostomy (OR, 0.32; 95% CI, 0.16-0.64; P < 0.001) decreased the occurrence of DGE.

CONCLUSIONS

Delayed gastric emptying was linked to the occurrence of postoperative intra-abdominal complications, and reconstruction by pancreaticogastrostomy was beneficial by decreasing its incidence.

The International Study Group of Pancreatic Surgery definition of delayed gastric emptying and the effects of various surgical modifications on the occurrence of delayed gastric emptying after pancreatoduodenectomy

BACKGROUND

A number of definitions have been used for delayed gastric emptying (DGE) after pancreatoduodenectomy and the reported rates varied widely. The International Study Group of Pancreatic Surgery (ISGPS) definition is the current standard but it is not used universally. In this comprehensive review, we aimed to determine the acceptance rate of ISGPS definition of DGE, the incidence of DGE after pancreatoduodenectomy and the effect of various technical modifications on its incidence.

DATA SOURCE

We searched PubMed for studies regarding DGE after pancreatoduodenectomy that were published from 1 January 1980 to 1 July 2015 and extracted data on DGE definition, DGE rates and comparison of DGE rates among different technical modifications from all of the relevant articles.

RESULTS

Out of 435 search results, 178 were selected for data extraction. The ISGPS definition was used in 80% of the studies published since 2010 and the average rates of DGE and clinically relevant DGE were 27.7% (range: 0-100%; median: 18.7%) and 14.3% (range: 1.8%-58.2%; median: 13.6%), respectively. Pylorus preservation or retrocolic reconstruction were not associated with increased DGE rates. Although pyloric dilatation, Braun's entero-enterostomy and Billroth II reconstruction were associated with significantly lower DGE rates, pyloric ring resection appears to be most promising with favorable results in 7 out of 10 studies.

CONCLUSIONS

ISGPS definition of DGE has been used in majority of studies published after 2010. Clinically relevant DGE rates remain high at 14.3% despite a number of proposed surgical modifications. Pyloric ring resection seems to offer the most promising solution to reduce the occurrence of DGE.

Comparison of different feeding regimes after pancreatoduodenectomy - a retrospective cohort analysis

BACKGROUND

Delayed gastric emptying (DGE) is the most frequent pancreatic specific complication (PSC) after pancreaticoduodenectomy (PD). Several gastric decompression systems exist to manage DGE. Patients with a pancreatic tumor require prolonged nutrition; however, controversies exist concerning nutrition protocol after PD. The aim of the study was to assess the safety and efficacy of nasogastric (NG), gastrostomy (GT), and gastrojejunostomy (GJ) tubes with different feeding systems on postoperative courses.

METHODS

Between January 2013 and March 2016, 86 patients underwent PD with pancreaticogastrostomy. Patients were divided into three groups: GJ group with enteral nutrition (EN, n = 12, 14%), NG (n = 31, 36%) and GT groups (n = 43, 50%), both with total parenteral nutrition (TPN).

RESULTS

Patients in the GJ (n = 9, 75%) and GT (n = 18, 42%) groups had an American Society of Anesthesiologists (ASA) score of 3 more often than those in the NG group (n = 5, 16%, p ≤ 0.01). Multivariate analysis identified the GT tube with TPN as an independent risk factor of severe morbidity (p = 0.02) and DGE (p < 0.01). An ASA score of 3, jaundice, common pancreatic duct size ≤3 mm and soft pancreatic gland texture (p < 0.05) were found as independent risk factors of PSCs. Use of a GJ tube with EN, GT tube with TPN, jaundice, and PSCs were identified as independent risk factors for greater postoperative length of hospital stay (p < 0.01). Mean global hospitalization cost did not differ between groups.

CONCLUSION

GT tube insertion with TPN was associated with increased severe postoperative morbidity and DGE and should not be recommended. EN through a GJ tube after PD is feasible but does not have clear advantages on postoperative courses compared to an NG tube.

Angiolymphatic invasion as a prognostic fator in resected N0 pancreatic adenocarcinoma

Background:

Pancreatic adenocarcinoma remains one of the worst digestive cancers. Surgical resection is the main target when treating a patient with curative intent.

Aim:

To assess angiolymphatic invasion as a prognostic factor in resected pN0 pancreatic cancer.

Methods:

Thirty-eight patients were submitted to pancreatoduodenectomy due to head pancreatic cancer. Tumor size, margins, lymph nodes, pTNM staging, angiolymphatic and perineural invasion were described in the pathologists' reports.

Results:

Most patients were female. Overall median survival was 13 months. Gemcitabine was the regimen of choice for chemotherapy in selected patients; however, it did not improve overall survival. pR0 resection had better survival compared with pR1. Within the pN0 group, survival was significantly better in patients without angiolymphatic invasion.

Conclusion:

Angiolymphatic invasion in N0 pancreatoduodenectomy can be demonstrated by the Hematoxylin-Eosin stain and may predict a poor prognosis factor for those patients.

Chronic Gastrointestinal Dysmotility and Pain Following Total Pancreatectomy with Islet Autotransplantation for Chronic Pancreatitis

BACKGROUND

The prevalence and impact of chronic gastrointestinal dysmotility following total pancreactectomy with islet autotransplantation (TP-IAT) for chronic pancreatitis is not known.

METHODS

A cross-sectional study of all patients who underwent TP-IAT at our institution from August 2011 to November 2015 was undertaken. The GCSI (Gastroparesis Cardinal Symptom Index), PAGI-SYM (Patient Assessment of Upper Gastrointestinal Disorders-Symptom Severity Index), PAC-SYM (Patient Assessment of Constipation Symptoms), Bristol stool chart, 12-item Short Form Health Survey (SF-12), and visual analog scale for pain were administered ≥4 weeks following TP-IAT.

KEY RESULTS

The prevalence of any dysmotility symptoms in patients who completed the survey (33/45, 73%) post-TP-IAT was 45%. Post-TP-IAT, the mean reduction in opioid dosing was 77.6 oral morphine equivalents (OMEs) (95% CI 32.1-123.0, p = 0.002) with 42% of patients requiring no opioids. There was significant negative correlation between dysmotility scores and SF-12 physical scores (r = -0.46, p = 0.008, 95% CI -0.70 to -0.13). Self-reported abdominal pain had significant negative correlation with both physical and mental SF-12 scores (r = -0.67, p < 0.001, 95% CI -0.83 to -0.41 and r = -0.39, p = 0.03, 95% CI -0.65 to -0.04). There was no correlation between gastrointestinal dysmotility and self-reported pain.

CONCLUSIONS AND INFERENCES

Symptoms of chronic gastrointestinal dysmotility and chronic abdominal pain are common post-TP-IAT and will need to be better recognized and differentiated to improve the management of these patients.

Delayed gastric emptying following pancreaticoduodenectomy: Incidence, risk factors, and healthcare utilization

AIM

To characterize incidence and risk factors for delayed gastric emptying (DGE) following pancreaticoduodenectomy and examine its implications on healthcare utilization.

METHODS

A prospectively-maintained database was reviewed. DGE was classified using International Study Group of Pancreatic Surgery criteria. Patients who developed DGE and those who did not were compared.

RESULTS

Two hundred and seventy-six patients underwent pancreaticoduodenectomy (PD) (> 80% pylorus-preserving, antecolic-reconstruction). DGE developed in 49 patients (17.8%): 5.1% grade B, 3.6% grade C. Demographic, clinical, and operative variables were similar between patients with DGE and those without. DGE patients were more likely to present multiple complications (32.6% vs 4.4%, ≥ 3 complications, P < 0.001), including postoperative pancreatic fistula (POPF) (42.9% vs 18.9%, P = 0.001) and intra-abdominal abscess (IAA) (16.3% vs 4.0%, P = 0.012). Patients with DGE had longer hospital stay (median, 12 d vs 7 d, P < 0.001) and were more likely to require transitional care upon discharge (24.5% vs 6.6%, P < 0.001). On multivariate analysis, predictors for DGE included POPF [OR = 3.39 (1.35-8.52), P = 0.009] and IAA [OR = 1.51 (1.03-2.22), P = 0.035].

CONCLUSION

Although DGE occurred in < 20% of patients after PD, it was associated with increased healthcare utilization. Patients with POPF and IAA were at risk for DGE. Anticipating DGE can help individualize care and allocate resources to high-risk patients.

Does the Ileal Brake Contribute to Delayed Gastric Emptying After Pancreatoduodenectomy?

Delayed gastric emptying (DGE) represents a significant cause for morbidity following pancreatoduodenectomy (PD). At a time when no specific and universally effective therapy exists to treat these patients, elucidating other potential (preventable or treatable) mechanisms for DGE is important. The aim of the manuscript was to test the hypothesis that ileal brake contributes to DGE in PD patients receiving jejunal tube feeding by systematically reviewing experimental and clinical literature. A series of clinically relevant questions were framed related to the potential role of the ileal brake in development of DGE post-PD and formed the basis of targeted literature searches. A comprehensive search of major reference databases from January 1980 to June 2015 was carried out which included human and animal studies. The ileal brake is a feedback loop neurally mediated by the vagus and sympatho-adrenergic pathways and hormonally by gut peptides including glucagon-like peptide-1, peptide YY (PYY), and neurotensin. The most potent stimulus for this inhibitory reflex is intra-ileal fat. There is evidence to indicate the role of an inhibitory reflex (on gastric emptying) mediated by PYY and CCK which, in turn, are stimulated by nutrient delivery into the distal small intestine providing indirect support to the role of ileal brake in post-PD DGE. The ileal brake is a likely factor contributing to DGE post-PD. While there has been no study to directly test this hypothesis, there is compelling indirect evidence to support it. Designing a trial that would answer such a question appears to be the most appropriate way forward.

Enucleation: A treatment alternative for branch duct intraductal papillary mucinous neoplasms

BACKGROUND

Small, asymptomatic, branch-duct intraductal papillary mucinous neoplasms of the pancreas are often kept under surveillance despite their malignant potential. The management of branch-duct intraductal papillary mucinous neoplasm is controversial with regard to indications and extent of any operative intervention. The present study aimed to evaluate enucleation as an alternative operative approach for branch-duct intraductal papillary mucinous neoplasms to exclude and prevent malignancy.

METHODS

For branch-duct intraductal papillary mucinous neoplasms of <30 mm in diameter and an acceptable distance from the main pancreatic duct, enucleation was considered as the operative approach of choice. All patients scheduled for enucleation of branch-duct intraductal papillary mucinous neoplasm on the basis of these features between January 2004 and September 2014 were analyzed. Among these, patients with successful enucleation were compared with those who were scheduled for enucleation but converted intraoperatively to pancreatic resection (intention-to-treat analysis). End points were hospital morbidity and mortality as well as histopathology and functional outcome at a mean follow-up of 32 months.

RESULTS

In the study, 115 patients with presumed branch-duct intraductal papillary mucinous neoplasm and the intention to perform pancreatic enucleation were included; 87 enucleations were performed in 74 patients. In 41 patients, enucleation was converted to a pancreatic resection (procedure-specific success rate 64%); indications for conversion included location or size (46%), presence of multicystic lesions (39%), or involvement of the main pancreatic duct (15%). Of the 74 patients with enucleation, 64 branch-duct intraductal papillary mucinous neoplasms revealed low- (85%), 11% moderate dysplasia-, and 4% high-grade dysplasia on histology. Among converted resections, 6 intraductal papillary mucinous neoplasms revealed high-grade dysplasia or invasive carcinoma (15%). Intention-to-treat analysis with patients converted to pancreatic resection showed that enucleations resulted in less blood loss (100 vs 400 mL) and a shorter operation time (146 vs 255 minutes; P < .001 each). Postoperative morbidity including postoperative pancreatic fistula was similar in both groups. No mortality occurred after enucleation; after formal resection, 1 patient died due to multiorgan failure. Both hospital stay (10 vs 14 days) and rates of postoperative endocrine and exocrine dysfunction rates were less after enucleation (P < .02 each). Intraductal papillary mucinous neoplasm-specific recurrence rates (3% vs 6%) were similar in both groups.

CONCLUSION

Enucleation is a safe procedure that can be performed successfully in a high proportion of branch-duct intraductal papillary mucinous neoplasms and should be considered instead of standard resections as an important function-preserving alternative. Limitations may occur due to malignancy, size, localization, multilocularity, or main-duct involvement requiring conversion to a formal, anatomic resection. Beside the advantages in the short-term course, functional outcome seems to be superior after enucleation, and intraductal papillary mucinous neoplasm-specific recurrence rates are not increased compared with standard resections, at least at a mean follow-up of 32 months.

Clinical effectiveness of a pylorus-preserving procedure on total pancreatectomy with islet autotransplantation

BACKGROUND

The impact of pylorus preserving procedures (PP) on total pancreatectomy with islet autotransplantation (TPIAT) has not been examined. This study aimed to investigate the clinical impact of the PP on TPIAT.

METHODS

The Baylor Simmons Transplant Institute database was queried to identify seventy-three patients who underwent TPIAT from 2006 to 2014. All patients were investigated in postoperative complications, long-term nutritional status, and graft function.

RESULTS

Patients with PP did not face worse outcomes in terms of delayed gastric emptying and length of hospital stay. Also, nutritional status and metabolic outcome, such as body weight, serum albumin level, serum vitamin level, HbA1c level, graft survival rate and insulin independent rate, were similar between both groups.

CONCLUSIONS

Clinical results including the graft function indicated that patients undergoing TPIAT with PP did not amplify surgical complications such as delayed gastric emptying and showed no significant advantage of nutrition and metabolic outcome.