Optimizing prediction models for pancreatic fistula after pancreatectomy: Current status and future perspectives.

Postoperative pancreatic fistula (POPF) is a frequent complication after pancreatectomy, leading to increased morbidity and mortality. Optimizing prediction models for POPF has emerged as a critical focus in surgical research. Although over sixty models following pancreaticoduodenectomy, predominantly reliant on a variety of clinical, surgical, and radiological parameters, have been documented, their predictive accuracy remains suboptimal in external validation and across diverse populations. As models after distal pancreatectomy continue to be progressively reported, their external validation is eagerly anticipated. Conversely, POPF prediction after central pancreatectomy is in its nascent stage, warranting urgent need for further development and validation. The potential of machine learning and big data analytics offers promising prospects for enhancing the accuracy of prediction models by incorporating an extensive array of variables and optimizing algorithm performance. Moreover, there is potential for the development of personalized prediction models based on patient- or pancreas-specific factors and postoperative serum or drain fluid biomarkers to improve accuracy in identifying individuals at risk of POPF. In the future, prospective multicenter studies and the integration of novel imaging technologies, such as artificial intelligence-based radiomics, may further refine predictive models. Addressing these issues is anticipated to revolutionize risk stratification, clinical decision-making, and postoperative management in patients undergoing pancreatectomy.

Deep learning-based prediction of post-pancreaticoduodenectomy pancreatic fistula.

Postoperative pancreatic fistula is a life-threatening complication with an unmet need for accurate prediction. This study was aimed to develop preoperative artificial intelligence-based prediction models. Patients who underwent pancreaticoduodenectomy were enrolled and stratified into model development and validation sets by surgery between 2016 and 2017 or in 2018, respectively. Machine learning models based on clinical and body composition data, and deep learning models based on computed tomographic data, were developed, combined by ensemble voting, and final models were selected comparison with earlier model. Among the 1333 participants (training, n = 881; test, n = 452), postoperative pancreatic fistula occurred in 421 (47.8%) and 134 (31.8%) and clinically relevant postoperative pancreatic fistula occurred in 59 (6.7%) and 27 (6.0%) participants in the training and test datasets, respectively. In the test dataset, the area under the receiver operating curve [AUC (95% confidence interval)] of the selected preoperative model for predicting all and clinically relevant postoperative pancreatic fistula was 0.75 (0.71-0.80) and 0.68 (0.58-0.78). The ensemble model showed better predictive performance than the individual ML and DL models.

High hand grip strength is a significant risk factor and a useful predictor of postoperative pancreatic fistula following pancreaticoduodenectomy.

BACKGROUND: Postoperative pancreatic fistula (POPF) is one of the most critical complications of pancreaticoduodenectomy (PD). Studies on predictive factors for POPF that can be identified preoperatively are limited. Recent reports have highlighted the association between the preoperative nutritional status, including sarcopenia, and postoperative complications. We examined preoperative risk factors for POPF after PD, focusing on nutritional indicators. METHODS: A total of 153 consecutive patients who underwent PD at our institution were enrolled in this study. Preoperative nutritional parameters, including hand grip strength (HGS) and skeletal muscle mass as components of sarcopenia, were incorporated into the analysis. POPFs were categorized according to the International Study Group of Pancreatic Fistula (ISGPF) definition as biochemical (grade A) or clinically relevant (CR-POPF; grades B and C). RESULTS: Thirty-seven of the 153 patients (24.1%) fulfilled the ISGPF definition of CR-POPF postoperatively. In the univariate analysis, the incidence of CR-POPF was associated with male sex, non-pancreatic tumor diseases, a high body mass index, a high HGS and a high skeletal muscle mass index. In the multivariate analysis, non-pancreatic tumor diseases and an HGS ≥23.0 kg were selected as independent risk factors for CR-POPF (P <0.05). CONCLUSIONS: A high HGS, a screening tool for sarcopenia, was a risk factor for CR-POPF. It can accurately serve as a useful predictor of POPF risk in patients undergoing PD. These results highlight the potential of sarcopenia to reduce the incidence of POPF and highlight the need to clarify the mechanism of POPF occurrence.

Portable droplet-based real-time monitoring of pancreatic α-amylase in postoperative patients.

Postoperative complications after pancreatic surgery are frequent and can be life-threatening. Current clinical diagnostic strategies involve time-consuming quantification of α-amylase activity in abdominal drain fluid, which is performed on the first and third postoperative day. The lack of real-time monitoring may delay adjustment of medical treatment upon complications and worsen prognosis for patients. We report a bedside portable droplet-based millifluidic device enabling real-time sensing of drain α-amylase activity for postoperative monitoring of patients undergoing pancreatic surgery. Here, a tiny amount of drain liquid of patient samples is continuously collected and co-encapsulated with a starch reagent in nanoliter-sized droplets to track the fluorescence intensity released upon reaction with α-amylase. Comparing the α-amylase levels of 32 patients, 97 % of the results of the droplet-based millifluidic system matched the clinical data. Our method reduces the α-amylase assay duration to approximately 3 min with the limit of detection 7 nmol/s·L, enabling amylase activity monitoring at the bedside in clinical real-time. The presented droplet-based platform can be extended for analysis of different body fluids, diseases, and towards a broader range of biomarkers, including lipase, bilirubin, lactate, inflammation, or liquid biopsy markers, paving the way towards new standards in postoperative patient monitoring.

Evaluation of pancreatic chymotrypsin activity for on-site prediction of clinically relevant postoperative pancreatic fistula.

OBJECTIVES: Although the risk of complications due to postoperative pancreatic fistula (POPF) have been evaluated based on the amylase level in drained ascitic fluid, this method has much room for improvement regarding diagnostic accuracy and facility of the measurement. This study aimed to investigate the clinical value of measuring pancreatic chymotrypsin activity for rapid and accurate prediction of POPF after pancreaticoduodenectomy. METHODS: In 52 consecutive patients undergoing pancreaticoduodenectomy, the chymotrypsin activity in pancreatic juice was measured by calculating the increase in fluorescence intensity during the first 5 min after activation with an enzyme-activatable fluorophore. The predictive value for clinically relevant POPF (CR-POPF) was compared between this technique and the conventional method based on the amylase level. RESULTS: According to receiver operating characteristic analyses, pancreatic chymotrypsin activity on postoperative day (POD) 3 measured with a multiplate reader had the highest predictive value for CR-POPF (area under the curve [AUC], 0.752; P < 0.001), yielding 77.8 % sensitivity and 68.8 % specificity. The AUC and sensitivity/specificity of the amylase level in ascitic fluid on POD 3 were 0.695 (P = 0.053) and 77.8 %/41.2 %, respectively. Multivariable analysis identified high pancreatic chymotrypsin activity on POD 3 as an independent risk factor for CR-POPF. Measurement of pancreatic chymotrypsin activity with a prototype portable fluorescence photometer could significantly predict CR-POPF (AUC, 0.731; P = 0.010). CONCLUSION: Measurement of pancreatic chymotrypsin activity enabled accurate and rapid prediction of CR-POPF after pancreaticoduodenectomy. This can help surgeons to implement appropriate drain management at the patient's bedside without delay.

Combined pre-operative risk score predicts pancreatic leak after pancreatic resection.

BACKGROUND: Post-operative pancreatic fistula (POPF) is a major complication following pancreatectomy and is currently difficult to predict pre-operatively. This study aims to validate pre-operative risk factors and develop a novel combined score for the prediction of POPF in the pre-operative setting. METHODS: Data were collected from 2016 to 2021 for radiologic main pancreatic duct diameter (MPD), body mass index (BMI), physical status classified by American Society of Anesthesiologists (ASA), polypharmacy, mean platelet ratio (MPR), comorbidity-polypharmacy score (CPS), and a novel Combined Pancreatic Leak Prediction Score (CPLPS) (derived from MPD diameter, BMI, and CPS) were obtained from pre-operative data and analyzed for their independent association with POPF occurrence. RESULTS: In total, 166 patients who underwent pancreatectomy with pancreatic leak (Grade A, B, and C) occurring in 51(30.7%) of patients. Pre-operative radiologic MPD diameter < 4 mm (p < 0.001), < 5 mm (p < 0.001), < 6 mm (p = 0.001), BMI ≥ 25 (p = 0.009), and ≥ 30 (p = 0.017) were independently associated with the occurrence of pancreatic leak. CPLPS was also predictive of pancreatic leak following pancreatectomy on univariate (p = 0.005) and multivariate analysis (p = 0.036). CONCLUSION: MPD and BMI were independent risk factors predictive for the development of pancreatic leak. CPLPS, was an independent predictor of pancreatic leak following pancreatectomy and could be used to help guide surgical decision making and patient counseling.

Tomoelastography and Pancreatic Extracellular Volume Fraction Derived From MRI for Predicting Clinically Relevant Postoperative Pancreatic Fistula.

BACKGROUND: Pancreatic stiffness and extracellular volume fraction (ECV) are potential imaging biomarkers for pancreatic fibrosis. Clinically relevant postoperative fistula (CR-POPF) is one of the most severe complications after pancreaticoduodenectomy. Which imaging biomarker performs better for predicting the risk of CR-POPF remains unknown. PURPOSE: To evaluate the diagnostic performance of ECV and tomoelastography-derived pancreatic stiffness for predicting the risk of CR-POPF in patients undergoing pancreaticoduodenectomy. STUDY TYPE: Prospective. POPULATION: Eighty patients who underwent multiparametric pancreatic MRI before pancreaticoduodenectomy, among whom 16 developed CR-POPF and 64 did not. FIELD STRENGTH/SEQUENCE: 3 T/tomoelastography and precontrast and postcontrast T1 mapping of the pancreas. ASSESSMENT: Pancreatic stiffness was measured on the tomographic c-map, and pancreatic ECV was calculated from precontrast and postcontrast T1 maps. Pancreatic stiffness and ECV were compared with histological fibrosis grading (F0-F3). The optimal cutoff values for predicting CR-POPF were determined, and the correlation between CR-POPF and imaging parameters was evaluated. STATISTICAL TESTS: The Spearman's rank correlation and multivariate linear regression analysis was conducted. The receiver operating characteristic curve analysis and logistic regression analysis was performed. A double-sided P < 0.05 indicated a statistically significant difference. RESULTS: Pancreatic stiffness and ECV both showed a significantly positive correlation with histological pancreatic fibrosis (r = 0.73 and 0.56, respectively). Patients with advanced pancreatic fibrosis had significantly higher pancreatic stiffness and ECV compared to those with no/mild fibrosis. Pancreatic stiffness and ECV were also correlated with each other (r = 0.58). Lower pancreatic stiffness (<1.38 m/sec), lower ECV (<0.28), nondilated main pancreatic duct (<3 mm) and pathological diagnosis other than pancreatic ductal adenocarcinoma were associated with higher risk of CR-POPF at univariate analysis, and pancreatic stiffness was independently associated with CR-POPF at multivariate analysis (odds ratio: 18.59, 95% confidence interval: 4.45, 77.69). DATA CONCLUSION: Pancreatic stiffness and ECV were associated with histological fibrosis grading, and pancreatic stiffness was an independent predictor for CR-POPF. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY STAGE: 5.

No Drain, No Problem: Serum-Based Marker Prediction of Clinically Relevant Postoperative Pancreatic Fistula.

BACKGROUND: Postoperative day (POD) 1 drain amylase concentration (DAC) is considered the most accurate predictor for the development of a clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy (PD). Recent studies have associated drain placement with negative postoperative outcomes. This study aims to evaluate multiple biochemical markers and their associations with CR-POPF development in order to identify a reliable, non-drain dependent alternative to DAC. METHODS: This is a review of 53 consecutive PD patients between 2021 and 2022. Albumin, C-reactive protein (CRP), C-reactive protein-to-albumin ratio (CAR), DAC, white blood cell count, and procalcitonin values were compared by CR-POPF status. The discriminatory abilities of CAR, CRP, and DAC for CR-POPF were compared using receiver operating characteristic (ROC) curves. RESULTS: Six of 51 included patients developed a CR-POPF. Receiver operating characteristic curve analysis produced an area under the curve of .977 for POD 1 DAC (cut-off 5131.0 IU/L, sensitivity 100%, specificity 95.5%), .858 for POD 1 CRP (cut-off 52.5 mg/L, sensitivity 100%, specificity 72.7%), and 1.000 for POD 3 CAR (cut-off 99.2, sensitivity and specificity 100%). POD 3 CAR produced a positive and negative predictive value of 100%. CONCLUSION: The CAR and CRP provide early and accurate identification of patients with post-PD CR-POPFs. These markers offer a method of safe CR-POPF detection, when the gold standard DAC is unavailable, ultimately allowing for early intervention and patient rescue.

The cholinesterase and C-reactive protein score is a potential predictor of pseudoaneurysm formation after pancreaticoduodenectomy in patients with soft pancreas.

BACKGROUND: Pseudoaneurysm (PA) rupture after pancreaticoduodenectomy (PD) is a life-threatening complication. Most PA cases originate from postoperative pancreatic fistulas (POPFs). Although several risk factors for POPF have been identified, specific risk factors for PA formation remain unclear. Therefore, we retrospectively analyzed PD cases with soft pancreas and proposed a novel strategy for early detection of PA formation. METHODS: Overall, 120 patients underwent PD between 2010 and 2020 at our institution; of these, 65 patients with soft pancreas were enrolled. We evaluated the clinicopathological factors influencing PA formation and developed a risk score to predict PA formation. RESULTS: In total, 11 of the 65 patients developed PAs (PA formation group: PAG), and 8 of these 11 PAs ruptured. The median time to PA formation was 15 days, with a minimum of 5 days. The PAG was significantly older than the non-PA formation group, were predominantly men, and had comorbid diabetes mellitus. Pre- and intra-operative findings were similar between the two groups. Importantly, no significant differences were found in postoperative drain amylase levels and total drain amylase content. Cholinesterase and C-reactive protein (CRP) levels on postoperative day (POD) 3 were significantly different between the two groups. Multivariate analysis showed that cholinesterase ≤ 112 U/L and CRP ≥ 16.0 mg/dl on POD 3 were independent predictors of PA formation. CONCLUSIONS: Decreased cholinesterase and elevated CRP on POD 3 (Cho-C score) are useful predictors of PA formation in cases with soft pancreas. In such cases, periodic computed tomography evaluations and strict drain management are necessary to prevent life-threatening hemorrhage.

The Role of C-reactive Protein and Procalcitonin in Predicting the Occurrence of Pancreatic Fistula in Patients who Underwent Laparoscopic Pancreaticoduodenectomy: a Retrospective Study.

The occurrence of postoperative pancreatic fistula following laparoscopic pancreaticoduodenectomy (LPD) is a significant concern, yet there is currently a lack of consensus on reliable predictive methods for this complication. Therefore, the aim of this study was to assess the clinical significance of C-reactive protein (CRP) and procalcitonin (PCT) values and their reliability in early predicting the development of clinically relevant pancreatic fistula (CRPF) following LPD.A retrospective analysis was conducted using data from 120 patients who had LPD between September 2019 and December 2021. Preoperative assessment data, standard patients' demographic and clinicopathological characteristics, intra- and postoperative evaluation, as well as postoperative laboratory values on postoperative days (PODs) 1, 3, and 7, including white blood cells (WBCs), CRP, and PCT, were prospectively recorded on a dedicated database. Two clinicians separately collected and cross-checked all of the data.Among 120 patients [77 men (64%), 43 women (36%], CRPF occurred in 15 patients (11 grade B and 4 grade C fistulas). The incidence rate of CRPF was 12.3%. A comparison of the median values of WBCs, PCT, and CRP across the two groups revealed that the CRPF group had higher values on most PODs than the non-CRPF group. Receiver operating characteristic (ROC) analysis was used to calculate the area under the curve (AUC) and cutoff values. It was discovered that POD 3 has the most accurate and significant values for WBCs, CRP, and PCT. According to the ROC plots, the AUC for WBCs was 0.842, whereas the AUC for PCT was 0.909. As for CRP, the AUC was 0.941 (95% CI 0.899-0.983, p < 0.01) with a cutoff value of 203.45, indicating a sensitivity of 93.3% and specificity of 91.4%.Both CRP and PCT can be used to predict the early onset of CRPF following LPD, with CRP being slightly superior on POD 3.

Drain fluid volume combined with amylase level predicts clinically relevant postoperative pancreatic fistula after pancreaticoduodenectomy: A retrospective clinical study.

BACKGROUND AND AIM: Several indicators are recognized in the development of clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy (PD). However, drain fluid volume (DFV) remains poorly studied. We aimed to discover the predictive effects of DFV and guide clinical management. METHODS: We retrospectively reviewed the clinical data of patients that received PD between January 2015 and December 2019 in a high-volume center. DFV was analyzed as a potential risk factor and postoperative short-term outcomes as well as drain removal time were compared stratified by different DFV levels. Receiver operating characteristic curves and area under curves (AUC) were compared for DFV alone and DFV combined with drain fluid amylase (DFA). Subgroup analysis of DFV stratified by DFA evaluated the predictability of CR-POPF. RESULTS: CR-POPF occurred in 19.7% of 841 patients. Hypertension, postoperative day 3 (POD3) DFA ≥ 300 U/L, and POD3 DFV ≥ 30 mL were independent risk factors, while pancreatic main duct diameter ≥ 3 mm was a protective factor. POD3 DFV ≥ 30 mL increased the overall occurrences of CR-POPF and major complications (P = 0.017; P = 0.029). POD3 DFV alone presented a low predictive value (AUC 0.602), while POD3 DFV combined with DFA had a high predictive value (AUC 0.759) for CR-POPF. Subgroup analysis showed that the combination of POD3 DFV ≥ 30 mL and DFA ≥ 300 U/L led to higher incidences of CR-POPF (P = 0.003). CONCLUSION: CR-POPF is common after PD, and high DFV combined with DFA may predict its occurrence and facilitate appropriate management.

A novel prediction model of pancreatic fistula after pancreaticoduodenectomy using only preoperative markers.

BACKGROUND: Since clinically relevant postoperative pancreatic fistula (CR-POPF) can cause intra-abdominal hemorrhage and abscesses, leading to surgery-related deaths after pancreaticoduodenectomy (PD), its preoperative prediction is important to develop strategies for surgical procedures and perioperative management. This study aimed to establish a novel prediction model for CR-POPF using preoperative markers. METHODS: On a training set of 180 patients who underwent PD at the Yamaguchi University Hospital, a combination of CR-POPF predictors were explored using the leave-one-out method with a unique discrete Bayes classifier. This predictive model was confirmed using a validation set of 366 patients who underwent PD at the Osaka University Hospital. RESULTS: In the training set, CR-POPF occurred in 60 (33%)　of 180 patients and 130 (36%)　of 366 patients in the validation set using selected markers. In patients with pancreatic ductal adenocarcinoma (PDAC), the main pancreatic duct (MPD) index showed the highest prognostic performance and could differentiate CR-POPF with 87% sensitivity and 81% specificity among 84 patients in the training set. In the validation set, the sensitivity and specificity of the MPD index-based model for 130 PDAC samples were 93% and 87%, respectively. In patients with non-PDAC, the MPD index/body mass index (BMI) combination showed the highest prognostic performance and could differentiate CR-POPF with 84% sensitivity and 57% specificity among 96 patients in the training set. In the validation set, the sensitivity and specificity of the MPD index/BMI-based model for 236 non-PDAC samples were 85% and 53%, respectively. CONCLUSION: We developed a novel prediction model for pancreatic fistulas after PD using only preoperative markers. The MPD index and MPD index/BMI combination will be useful for CR-POPF assessment in PDAC and non-PDAC samples, respectively.

External validation of fistula risk scores for postoperative pancreatic fistula after distal pancreatectomy.

BACKGROUND: Fistula risk scores such as distal fistula risk scores and DISPAIR have been recently developed to assess the risk of clinically relevant postoperative pancreatic fistula after distal pancreatectomy. This study aimed to validate these models externally using a large-scale Chinese cohort. METHODS: The study enrolled adult patients who underwent distal pancreatectomy at a high-volume single center between January 2011 and December 2021. The clinically relevant postoperative pancreatic fistula was defined as grade B/C, according to the 2016 International Study Group of Pancreatic Surgery. Model performance was evaluated using the area under the curve. RESULTS: Among 653 eligible patients, 126 (19.3%) suffered from clinically relevant postoperative pancreatic fistulas. Independent predictors for clinically relevant postoperative pancreatic fistulas included body mass index, diabetes mellitus, pancreatic thickness at both neck and transection sites, main pancreatic duct diameter, and soft pancreas. Clinically relevant postoperative pancreatic fistula risk increased with increasing score severity. All 3 prediction models showed acceptable discrimination, with area under the curve values of preoperative distal fistula risk score at 0.723 (95% confidence interval 0.687-0.757), intraoperative distal fistula risk score at 0.737 (95% confidence interval 0.701-0.770), and DISPAIR at 0.721 (95% confidence interval 0.685-0.755). No significant differences were found among them. CONCLUSION: Distal fistula risk scores and DISPAIR are useful tools for predicting clinically relevant postoperative pancreatic fistula after distal pancreatectomy, highlighting their importance in guiding surgical approach decisions and mitigating strategies against this complication in clinical practice.

Development and validation of a novel nomogram to predict postoperative pancreatic fistula after pancreatoduodenectomy using lasso-logistic regression: an international multi-institutional observational study.

BACKGROUND: Existing prediction models for clinically relevant postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD) lack discriminatory power or are too complex. This study aimed to develop a simple nomogram that could accurately predict clinically relevant POPF after PD. METHODS: A high-volume, multicenter cohort of patients who underwent PD from the American College of Surgeons-National Surgical Quality Improvement Program database in the United States during 2014-2017 was used as the model training cohort ( n =3609), and patients who underwent PD from the Pancreatic Center of the National Cancer Center Hospital in China during 2014-2019 were used as the external validation cohort ( n =1347). The study used lasso penalized regression to screen large-scale variables, then logistic regression was performed to screen the variables and build a model. Finally, a prediction nomogram for clinically relevant POPF was established based on the logistic model, and polynomial equations were extracted. The performance of the nomogram was evaluated by receiver operating characteristic curve, calibration curve, and decision curve analysis. RESULTS: In the training and validation cohorts, there were 16.7% (601/3609) and 16.6% (224/1347) of patients who developed clinically relevant POPF, respectively. After screening using lasso and logistic regression, only six predictors were independently associated with clinically relevant POPF, including two preoperative indicators (weight and pancreatic duct size), one intraoperative indicator (pancreatic texture), and three postoperative indicators (deep surgical site infection, delayed gastric emptying, and pathology). The prediction of the new nomogram was accurate, with an area under the curve of 0.855 (95% CI: 0.702-0.853) in the external validation cohort, and the predictive performance was superior to three previously proposed POPF risk score models (all P <0.001, likelihood ratio test). CONCLUSIONS: A reliable lasso-logistic method was applied to establish a novel nomogram based on six readily available indicators, achieving a sustained, dynamic, and precise POPF prediction for PD patients. With a limited number of variables and easy clinical application, this new model will enable surgeons to proactively predict, identify, and manage pancreatic fistulas to obtain better outcomes from this daunting postoperative complication.

Serum amylase on postoperative day 1 is superior to serum lipase in predicting clinically relevant pancreatic fistula after partial pancreaticoduodenectomy.

PURPOSE: To compare the predictive value of serum amylase and lipase regarding the occurrence of clinically relevant postoperative pancreatic fistula (cr-POPF) after partial pancreaticoduodenectomy (PD). METHODS: Data from 228 consecutive patients undergoing PD were obtained from a prospective database. Serum amylase and lipase were measured on postoperative days (PODs) 0-2. Receiver-operating characteristics analysis was performed and cutoff values were tested using logistic regression. RESULTS: Serum amylase had a larger area under the curve (AUC) on POD1 (AUC 0.89, p <0.001) than serum lipase. For serum amylase POD 1, a cutoff value of 70 U/l showed sensitivity and specificity of 100% and 70% for the diagnosis of cr-POPF. Serum amylase POD 1 > 70 U/l (OR 9.815, 95% CI 3.683-26.152, p < 0.001), drain amylase POD 1 > 300 U/l (OR 2.777, 95% CI 1.071-7.197, p= 0.036), and a small (≤ 3mm) pancreatic duct diameter (OR 3.705, 95% CI 1.426-9.627, p= 0.007) were significant predictors of cr-POPF in the multivariable analysis. Patients were divided into three risk groups based on serum amylase POD 1 and pancreatic duct diameter. This model had a good performance in discriminating cr-POPF (AUC 0.846, 95% CI 0.793-0.898). The sensitivity, specificity, and negative predictive value for the combination of serum amylase POD 1 <70 U/l and pancreatic duct diameter >3 mm were 100%, 70%, and 100%. CONCLUSION: Serum amylase POD 1 was superior to serum lipase in predicting cr-POPF after PD. The proposed risk prediction model had a sensitivity and negative predictive value of 100%, allowing for early identification of cr-POPF.

Early postoperative risk stratification in patients with pancreatic fistula after pancreaticoduodenectomy.

BACKGROUND: Early stratification of postoperative pancreatic fistula according to severity and/or need for invasive intervention may improve outcomes after pancreaticoduodenectomy. This study aimed to identify the early postoperative variables that may predict postoperative pancreatic fistula severity. METHODS: All patients diagnosed with biochemical leak and clinically relevant-postoperative pancreatic fistula based on drain fluid amylase >300 U/L on the fifth postoperative day after pancreaticoduodenectomy were identified from a consecutive cohort from Birmingham, UK. Demographics, intraoperative parameters, and postoperative laboratory results on postoperative days 1 through 7 were retrospectively extracted. Independent predictors of clinically relevant-postoperative pancreatic fistula were identified using multivariable binary logistic regression and converted into a risk score, which was applied to an external cohort from Verona, Italy. RESULTS: The Birmingham cohort had 187 patients diagnosed with postoperative pancreatic fistula (biochemical leak: 99, clinically relevant: 88). In clinically relevant-postoperative pancreatic fistula patients, the leak became clinically relevant at a median of 9 days (interquartile range: 6-13) after pancreaticoduodenectomy. Male sex (P = .002), drain fluid amylase-postoperative day 3 (P < .001), c-reactive protein postoperative day 3 (P < .001), and albumin-postoperative day 3 (P = .028) were found to be significant predictors of clinically relevant-postoperative pancreatic fistula on multivariable analysis. The multivariable model was converted into a risk score with an area under the receiver operating characteristic curve of 0.78 (standard error: 0.038). This score significantly predicted the need for invasive intervention (postoperative pancreatic fistula grades B3 and C) in the Verona cohort (n = 121; area under the receiver operating characteristic curve: 0.68; standard error = 0.06; P = .006) but did not predict clinically relevant-postoperative pancreatic fistula when grades B1 and B2 were included (area under the receiver operating characteristic curve 0.52; standard error = 0.07; P = .802). CONCLUSION: We developed a novel risk score based on early postoperative laboratory values that can accurately predict higher grades of clinically relevant-postoperative pancreatic fistula requiring invasive intervention. Early identification of severe postoperative pancreatic fistula may allow earlier intervention.

The risk of clinically-relevant pancreatic fistula after pancreaticoduodenectomy is better predicted by a postoperative trend in drain fluid amylase compared to day 1 values in isolation.

BACKGROUND: Recent studies support early drain removal after pancreaticoduodenectomy in patients with a drain fluid amylase on postoperative day 1 (DFA1) level of ≤5,000. The use of DFA1 to guide drain management is increasingly common among pancreatic surgeons; however, the benefit of checking additional drain fluid amylases beyond DFA1 is less known. We sought to determine whether a change in drain fluid amylase (ΔDFA) is a more reliable predictor of clinically relevant postoperative fistula than DFA1 alone. METHODS: Using the American College of Surgeons National Surgical Quality Improvement Plan, pancreaticoduodenectomy patients with intraoperative drain placement, known DFA1, highest recorded drain fluid amylase value on postoperative day 2 to 5 (DFA2nd), day of drain removal, and clinically relevant postoperative fistula status were reviewed. Logistic models compared the predictive performance of DFA1 alone versus DFA1 + ΔDFA. RESULTS: A total of 2,417 patients with an overall clinically relevant postoperative fistula rate of 12.6% were analyzed. On multivariable regression, clinical predictors for clinically relevant postoperative fistula included body mass index, steroid use, operative time, and gland texture. These variables were used to develop model 1 (DFA1 alone) and model 2 (DFA1 + ΔDFA). Model 2 outperformed model 1 in predicting the risk of clinically relevant postoperative fistula. According to model 2 predictions, the risk of clinically relevant postoperative fistula increased with any rise in drain fluid amylase, regardless of whether the DFA1 was above or below 5,000 U/L. The risk of clinically relevant postoperative fistula significantly decreased with any drop in drain fluid amylase, with an odds reduction of approximately 50% corresponding with a 70% decrease in drain fluid amylase (P < .001). A risk calculator was developed using DFA1 and a secondary DFA value in conjunction with other clinical predictors for clinically relevant postoperative fistula. CONCLUSION: Clinically relevant postoperative fistula after pancreaticoduodenectomy is more accurately predicted by DFA1 and ΔDFA versus DFA1 in isolation. We developed a novel risk calculator to provide an individualized approach to drain management after pancreaticoduodenectomy.