Postoperative serum hyperamylasemia (POH) predicts additional morbidity after pancreatoduodenectomy: It is not all about pancreatic fistula

Predictive value of postoperative serum lipase level for postoperative pancreatic fistula after pancreaticoduodenectomy

BACKGROUND

The prediction of postoperative pancreatic fistula (POPF) is important. This study aimed to investigate the role of postoperative serum lipase level in predicting POPF.

METHODS

Data from 234 consecutive patients who underwent pancreaticoduodenectomy (PD) were collected. The predictive values of serum amylase and serum lipase during postoperative days (PODs) 1 to 3 for POPF were compared. Subgroup analyses were performed to determine the prognostic value of different levels and durations of elevated serum lipase.

RESULTS

Fifty-six patients developed POPF. The POPF group exhibited increased levels of serum amylase and lipase from PODs 1 to 3 (all P < 0.001). Compared with serum amylase, serum lipase has greater predictive value for POPF. Specifically, serum lipase had the highest area under the receiver operating characteristic curve (AUC) at POD 1 (0.791). Body mass index > 24 kg/m2 [odds ratio (OR) = 2.431, 95% confidence interval (CI): 1.094-5.404, P = 0.029], soft pancreatic texture (OR = 3.189, 95% CI: 1.263-8.056, P = 0.014), serum lipase > 60 U/L at POD 1 (OR = 5.135, 95% CI: 1.257-20.982, P = 0.023), and C-reactive protein > 167 mg/dL at POD 3 (OR = 3.607, 95% CI: 1.431-9.090, P = 0.007) were identified as independent risk factors for POPF. Patients with serum lipase ≤ 60 U/L at POD 1 (n = 104) exhibited lower rates of POPF (3.8% vs. 40.0%, P < 0.001) and severe complications (Clavien-Dindo ≥ IIIa) (4.8% vs. 25.4%, P < 0.001) than those with serum lipase > 60 U/L at POD 1. Moreover, no additional elevation or duration of serum lipase offered any further prognostic value.

CONCLUSIONS

Postoperative serum lipase outperformed serum amylase in the prediction of POPF, and patients with normal serum lipase level at POD 1 had favorable outcomes. A sustained increase in the serum lipase level offers no additional prognostic value.

Machine learning model-based prediction of postpancreatectomy acute pancreatitis following pancreaticoduodenectomy: A retrospective cohort study

BACKGROUND

The International Study Group of Pancreatic Surgery has established the definition and grading system for postpancreatectomy acute pancreatitis (PPAP). There are no established machine learning models for predicting PPAP following pancreaticoduodenectomy (PD).

AIM

To explore the predictive model of PPAP, and test its predictive efficacy to guide the clinical work.

METHODS

Clinical data from consecutive patients who underwent PD between 2016 and 2024 were retrospectively collected. An analysis of PPAP risk factors was performed, various machine learning algorithms [logistic regression, random forest, gradient boosting decision tree, extreme gradient boosting, light gradient boosting machine, and category boosting (CatBoost)] were utilized to develop predictive models. Recursive feature elimination was employed to select several variables to achieve the optimal machine algorithm.

RESULTS

The study included 381 patients, of whom 88 (23.09%) developed PPAP. PPAP patients exhibited a significantly higher incidence of postoperative pancreatic fistula (55.68% vs 14.68%, P < 0.001), grade C postoperative pancreatic fistula (9.09% vs 1.37%, P = 0.001). The CatBoost algorithm outperformed other algorithms with a mean area under the receiver operating characteristic curve of 0.859 [95% confidence interval (CI): 0.814-0.905] in the training cohort and 0.822 (95%CI: 0.717-0.927) in the testing cohort. According to shapley additive explanations analysis, pancreatic texture, main pancreatic duct diameter, body mass index, estimated blood loss, and surgery time were the most important variables based on recursive feature elimination. The CatBoost algorithm based on selected variables demonstrated superior performance, with an area under the receiver operating characteristic curve of 0.837 (95%CI: 0.788-0.886) in the training cohort and 0.812 (95%CI: 0.697-0.927) in the testing cohort.

CONCLUSION

We developed the first machine learning-based predictive model for PPAP following PD. This predictive model can assist surgeons in anticipating and managing this complication proactively.

Hyperlipasemia in the immediate postoperative period predicts postoperative pancreatic fistula after pancreatic resections

BACKGROUND

Postoperative pancreatic fistula is the most common severe complication after pancreatic surgery. It associated with increased morbidity and prolonged hospital stay. Identifying patients at low risk for postoperative pancreatic fistula is essential to enable timely removal of drains and facilitate early discharge. Although postoperative hyperamylasemia is linked to postoperative pancreatic fistula, the role of postoperative hyperlipasemia remains unclear. This study aims to investigate the role of postoperative hyperlipasemia in predicting postoperative pancreatic fistula B/C pancreaticoduodenectomy and distal pancreatectomy.

MATERIAL AND METHODS

The study included 471 patients who underwent pancreaticoduodenectomy and distal pancreatectomy at our institution between January 1, 2019, and February 28, 2023. Postoperative hyperamylasemia and postoperative hyperlipasemia were defined as values above the upper limit of normal established at our institution.

RESULTS

In univariate analysis, postoperative hyperlipasemia and postoperative hyperamylasemia on postoperative day 0 demonstrated the strongest association with postoperative pancreatic fistula B/C. Consequently, a subset of 177 patients with available serum lipase and amylase data underwent further investigation. Besides body mass index and high-risk pathology, both postoperative hyperlipasemia and postoperative hyperamylasemia on postoperative day 0 emerged as independent risk factors for postoperative pancreatic fistula B/C in univariate analysis. In multivariate analysis, postoperative hyperlipasemia on postoperative day 0 emerged as a significant predictor of postoperative pancreatic fistula B/C, with body mass index as independent risk factor of postoperative pancreatic fistula B/C.

CONCLUSION

The absence of postoperative hyperlipasemia on postoperative day 0 could potentially serve as an effective diagnostic tool for identifying patients who are at a low risk of developing postoperative pancreatic fistula B/C after pancreaticoduodenectomy and distal pancreatectomy. Consequently, not only serum amylase, but also serum lipase can be integrated into clinical practice alongside other relevant parameters.

Thirty-day prevalence and clinical impact of fluid collections at the resection margin after distal pancreatectomy: Follow-up of a multicentric randomized controlled trial

BACKGROUND

Postoperative fluid collections at the resection margin of the pancreatic stump are frequent after distal pancreatectomy, yet their clinical impact is unclear. The aim of this study was to assess the 30-day prevalence of postoperative fluid collections after distal pancreatectomy and the factors associated with a clinically relevant condition.

METHODS

Patients enrolled in a randomized controlled trial of parenchymal transection with either reinforced, triple-row staple, or ultrasonic dissector underwent routine magnetic resonance 30 days postoperatively. Postoperative fluid collection was defined as a cyst-like lesion of at least 1 cm at the pancreatic resection margin. Postoperative fluid collections requiring any therapy were defined as clinically relevant.

RESULTS

A total of 133 patients were analyzed; 69 were in the triple-row staple transection arm, and 64 were in the ultrasonic dissector transection arm. The overall 30-day prevalence of postoperative fluid collections was 68% (n = 90), without any significant difference between the two trial arms. Postoperative serum hyperamylasemia was more frequent in patients with postoperative fluid collections than those without (31% vs 7%, P = .001). Among the postoperative fluid collection population, an early postoperative pancreatic fistula (odds ratio 14.9, P = .002), post pancreatectomy acute pancreatitis (odds ratio 12.7, P = .036), and postoperative fluid collection size larger than 50 mm (odds ratio 6.6, P = .046) were independently associated with a clinically relevant postoperative fluid collection.

CONCLUSION

Postoperative fluid collections at the resection margin are common after distal pancreatectomy and can be predicted by early assessment of postoperative serum hyperamylasemia. A preceding pancreatectomy acute pancreatitis and/or postoperative pancreatic fistula and large collections (>50 mm) were associated with a clinically relevant postoperative fluid collection, representing targets for closer follow-up or earlier therapeutic interventions.

Textbook outcome after pancreatoduodenectomy and distal pancreatectomy with postoperative hyperamylasemia-a propensity score matching analysis

PURPOSE

Postoperative serum hyperamylasemia (POH) is a part of the new, increasingly highlighted, definition for postpancreatectomy pancreatitis (PPAP). This study aimed to analyze whether the biochemical changes of PPAP are differently associated with postoperative complications after distal pancreatectomy (DP) compared with pancreatoduodenectomy (PD). The textbook outcome (TO) was used as a summary measure to capture real-world data.

METHODS

The data were retrospectively extracted from a prospective clinical database. Patients with POH, defined as levels above our institution's upper limit of normal on postoperative day 1, after DP and the corresponding propensity score-matched cohort after PD were evaluated on postoperative complications by using logistic regression analyses.

RESULTS

We analyzed 723 patients who underwent PD and DP over a period of 9 years. After propensity score matching, 384 patients (192 patients in each group) remained. POH was observed in 78 (41.1%) and 74 (39.4%) after PD and DP correspondingly. There was a significant increase of postoperative complications in the PD group: Clavien-Dindo classification system ≥3 (P < .01 vs P = .71), clinically relevant postoperative pancreatic fistula (P < .001 vs P = .2), postpancreatectomy hemorrhage (P < .001 vs P = .11), and length of hospital stay (P < .001 vs P = .69) if POH occurred compared with in the DP group. TO was significantly unlikely in cases with POH after PD compared with DP (P > .001 vs P = .41). Furthermore, POH was found to be an independent predictor for missing TO after PD (odds ratio [OR], 0.29; 95% CI, 0.14-0.60; P < .001), whereas this was not observed in patients after DP (OR, 0.53; 95% CI, 0.21-1.33; P = .18).

CONCLUSION

As a part of the definition for PPAP, POH is a predictive indicator associated with postoperative complications after PD but not after DP.

No role for protease inhibitors as a mitigation strategy for postpancreatectomy acute pancreatitis (PPAP): Propensity score matching analysis

BACKGROUND

While the use of protease inhibitor gabexate mesylate (GM) is still controversial in acute pancreatitis, it has never been tested for postpancreatectomy acute pancreatitis (PPAP). This study aims to assess the impact of GM on postoperative serum hyperamylasaemia (POH) or PPAP after pancreatoduodenectomy (PD).

METHODS

Consecutive patients developing POH after PD between 2016 and 2021 were included. According to GM administration, patients were divided into GM-treated and control (CTR) groups. GM was administered from postoperative day 1-3 in POH patients who underwent surgery before 2017. A 2:1 propensity matching was used to minimize the risk of bias.

RESULTS

Overall, 264 patients with POH were stratified in the GM (59 patients) and CTR (104 patients) cohorts, which showed balanced baseline characteristics after matching. No difference in postoperative complications was observed between the groups (all p > 0.05), except for PPAP occurrence, which was significantly higher in the GM group (37% vs. 22%, p = 0.037). A total of 45 patients (28%) evolved to PPAP. Comparing PPAP patients in the GM and CTR groups, no significant differences in POPF, relaparotomy, and mortality (all p > 0.09) were found. No difference in intravenous crystalloid administration was found in patients with PPAP, whether or not they developed major complications or pancreatic fistula (p > 0.05) CONCLUSION: Protease inhibitor seems ineffective in preventing a PPAP after PD once a POH has occurred. Further studies are needed to achieve benchmarks for treating PPAP and identify mitigation strategies to prevent the evolution of POH into additional morbidity.

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.