OUP accepted manuscript

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.

Association of cephalosporin resistance in intraoperative biliary cultures with surgical site infections in patients undergoing pancreaticoduodenectomy. A retrospective cohort study

BACKGROUND

The aim of this study was to assess the incidence of bacterobilia at the time of a pancreaticoduodenectomy (PD) and the association of resistant bacteria in bile to surgical site infections (SSI).

METHODS

This was a retrospective cohort study including patients undergoing PD in a single center between May 2016 and October 2020. Data of preoperative biliary drainage (PBD), intraoperative biliary cultures (IBC) and postoperative complications were analysed to assess the risk factors for resistant bacteria in IBC and SSIs.

RESULTS

Of 361 patients included, 254 (70%) had undergone PBD. Second-generation cephalosporin resistant bacteria were found in IBC of 183 (64%) of all the patients. PBD was the only risk factor for second-generation cephalosporin resistance. The risk for second-generation cephalosporin resistance was more than 20-fold in patients with PBD [n = 170/254 (67%) (OR 22.58 (95% CI, 9.61-53.01), p < 0.001)] compared to patients who did not have PBD (n = 13/107 (12%)). Also, if the time between PBD and surgery was 2 months or more the second-generation cephalosporin resistance in IBC increased the risk for SSIs (OR 4.14 (95% CI, 1.18-14.51), p = 0.027).

CONCLUSION

The second-generation cephalosporin resistance in IBC is common in patients who have undergone PBD. Broad-spectrum antibiotics in prophylaxis may be beneficial for these patients.

Risk Factors of Postoperative Acute Pancreatitis and Its Impact on the Postoperative Course after Pancreaticoduodenectomy-10 Years of Single-Center Experience

BACKGROUND

Clinically relevant acute postoperative pancreatitis (CR-PPAP) after pancreaticoduodenectomy (PD) is a complication that may lead to the development of local and systemic consequences. The study aimed to identify risk factors for CR-PPAP and assess the impact of CR-PPAP on the postoperative course after PD.

METHODS

The study retrospectively analyzed data from 428 consecutive patients who underwent PD at a single center between January 2013 and December 2022. The presence of increased amylase activity in plasma, above the upper limit of normal 48 h after surgery, was checked. CR-PPAP was diagnosed when accompanied by disturbing radiological features and/or symptoms requiring treatment. We investigated the relationship between the occurrence of CR-PPAP and the development of postoperative complications after PD, and possible predictors of CR-PPAP.

RESULTS

The postoperative follow-up period was 90 days. Of the 428 patients, 18.2% (n = 78) had CR-PPAP. It was associated with increased rates of CR-POPF, delayed gastric emptying, occurrence of intra-abdominal collections, postoperative hemorrhage, peritonitis, and septic shock. Patients who developed CR-PPAP were more often reoperated (37.17% vs. 6.9%, p < 0.0001)) and had increased postoperative mortality (14.1% vs. 5.74%, p < 0.0001). Soft pancreatic parenchyma, intraoperative blood loss, small diameter of the pancreatic duct, and diagnosis of adenocarcinoma papillae Vateri were independent risk factors for CR-PPAP and showed the best performance in predicting CR-PPAP.

CONCLUSIONS

CR-PPAP is associated with an increased incidence of postoperative complications after PD, worse treatment outcomes, and an increased risk of reoperation and mortality. Pancreatic consistency, intraoperative blood loss, width of the duct of Wirsung, and histopathological diagnosis can be used to assess the risk of CR-PPAP. Amylase activity 48 h after surgery > 161 U/L is highly specific in the diagnosis of CR-PPAP.

Pasireotide Versus Octreotide in Preventing Complications After Simultaneous Pancreas-Kidney Transplantation

In elective pancreatic surgery, somatostatin-analogues pasireotide and octreotide are variably used to reduce postoperative complications, but knowledge on their role in pancreas transplantation is limited. This study compared pasireotide and octreotide for their association with complications after simultaneous pancreas-kidney transplantation (SPK). This retrospective study included consecutive patients undergoing SPK's from July 2013 to July 2022. Between July 2013 and April 2020, octreotide was administered 0.1 mg s.c. once daily and between May 2020 and July 2022 pasireotide was administered 0.9 mg twice daily, both until third postoperative day. Complications within 90 days postoperatively were collected, and reoperation rate and Comprehensive Complication index (CCI) ≥ 33.7 (morbidity equal to one reoperation) were used as primary outcomes. Of the 213 patients undergoing SPK, 150 patients received octreotide and 63 pasireotide. Baseline characteristics were comparable. Reoperation rate was 25.3% (n = 38) and 17.5% (n = 11) (p = 0.213) and rate of CCI ≥ 33.7 was 40.7% (n = 61) and 30.2% (n = 19) (p = 0.148) in octreotide and pasireotide groups, respectively. When adjusted with donor BMI, pancreas donor risk index, and donor sex, receiving pasireotide translated into OR 0.49 (95% CI: 0.25-0.96 p = 0.037) for CCI ≥ 33.7. Pasireotide was independently associated with lower postoperative morbidity within 90 days of SPK compared to octreotide.

Incidence and risk factors of postoperative acute pancreatitis after pancreaticoduodenectomy: a systematic review and meta-analysis

Background

Postoperative acute pancreatitis (POAP) is a specific complication after pancreatectomy. The acute inflammatory response of the residual pancreas may affect the healing of pancreatoenteric anastomoses, leading to postoperative pancreatic fistulas (POPFs), abdominal infections, and even progressive systemic reactions, conditions that negatively affect patients' prognoses and can cause death. However, to the best of our knowledge, no systematic reviews or meta-analytic studies have assessed the incidence and risk factors of POAP after pancreaticoduodenectomy (PD).

Method

We searched PubMed, Web of Science, Embase, and Cochrane Library databases for relevant literature describing the outcomes of POAP after PD until November 25, 2022, and we used the Newcastle-Ottawa Scale to assess the quality of the studies. Next, we pooled the incidence of POAP and the odds ratios (ORs) and 95% confidence intervals (CIs) of the risk factors using a random-effect meta-analysis. I² tests were used to assess heterogeneity between the studies.

Results

We analyzed data from 7,164 patients after PD from 23 articles that met the inclusion criteria for this study. The subgroup results of the meta-analysis by different POAP diagnostic criteria showed that the incidences of POAP were 15% (95% CI, 5-38) in the International Study Group for Pancreatic Surgery group, 51% (95% CI, 42-60) in the Connor group, 7% (95% CI, 2-24) in the Atlanta group, and 5% (95% CI, 2-14) in the unclear group. Being a woman [OR (1.37, 95% CI, 1.06-1.77)] or having a soft pancreatic texture [OR (2.56, 95% CI, 1.70-3.86)] were risk factors of POAP after PD.

Conclusion

The results showed that POAP was common after PD, and its incidence varied widely according to different definitions. Large-scale reports are still needed, and surgeons should remain aware of this complication.

Systematic Review Registration

identifier: CRD42022375124.

Prediction of postoperative pancreatic fistula and pancreatitis after pancreatoduodenectomy or distal pancreatectomy: A review

BACKGROUND AND OBJECTIVE

Postoperative pancreatic fistula (POPF) is the leading cause of morbidity and early mortality in patients undergoing pancreatic resection. In addition, recent studies have identified postoperative acute pancreatitis (POAP) as an independent contributor to morbidity. Most perioperative mitigation strategies experimented for POPF have been shown to be in vain with no consensus on the best perioperative management. Clinical prediction models have been developed with the hope of identifying high POPF risk patients with the leading idea of finding subpopulations possibly benefiting from pre-existing or novel mitigation strategies. The aim of this review was to map out the existing prediction modeling studies to better understand the current stage of POPF prediction modeling, and the methodology behind them.

METHODS

A narrative review of the existing POPF prediction model studies was performed. Studies published before September 2022 were included.

RESULTS

While the number of POPF prediction models for pancreatoduodenectomy has increased, none of the currently existing models stand out from the crowd. For distal pancreatectomy, two unique POPF prediction models exist, but due to their freshness, no further external validation or adoption in clinics or research has been reported. There seems to be a lack of adherence to correct methodology or reporting guidelines in most of the studies, which has rendered external validity-if assessed-low. Few of the most recent studies have demonstrated preoperative assessment of pancreatic aspects from computed tomography (CT) scans to provide relatively strong predictors of POPF.

CONCLUSIONS

Main goal for the future would be to reach a consensus on the most important POPF predictors and prediction model. At their current state, few models have demonstrated adequate transportability and generalizability to be up to the task. Better understanding of POPF pathophysiology and the possible driving force of acute inflammation and POAP might be required before such a prediction model can be accessed.