Postpancreatectomy Acute Pancreatitis (PPAP): Definition and Grading From the International Study Group for Pancreatic Surgery (ISGPS)

Establishment and external validation of neutrophil-to-lymphocyte ratio in excluding postoperative pancreatic fistula after pancreatoduodenectomy

BACKGROUND

Factors excluding postoperative pancreatic fistula (POPF), facilitating early drain removal and hospital discharge represent a novel approach in patients undergoing enhanced recovery after pancreatic surgery. This study aimed to establish the relevance of neutrophil-to-lymphocyte ratio (NLR) in excluding POPF after pancreatoduodenectomy (PD).

METHODS

A prospectively maintained database of patients who underwent PD at two high-volume centres was used. Patients were divided into three cohorts (training, internal, and external validation). The primary endpoints of this study were accuracy, optimal timing, and cutoff values of NLR for excluding POPF after PD.

RESULTS

From 2012 to 2020, in a 2:1 ratio, 451 consecutive patients were randomly sampled as training (n = 301) and validation (n = 150) cohorts. Additionally, the external validation cohort included 197 patients between 2018 and 2020. POPF was diagnosed in 135 (20.8 per cent) patients. The 90-day mortality rate was 4.1 per cent. NLR less than 8.5 on postoperative day 3 (OR, 95 per cent c.i.) was significantly associated with the absence of POPF in the training (2.41, 1.19 to 4.88; P = 0.015), internal validation (5.59, 2.02 to 15.43; P = 0.001), and external validation (5.13, 1.67 to 15.76; P = 0.004) cohorts when adjusted for relevant clinical factors. Postoperative outcomes significantly differed using this threshold.

CONCLUSION

NLR less than 8.5 on postoperative day 3 may be a simple, independent, cost-effective, and easy-to-use criterion for excluding POPF.

Optimal Perioperative Fluid Therapy Associates with Fewer Complications After Pancreaticoduodenectomy

BACKGROUND

Optimal fluid management in pancreaticoduodenectomy patients remains contested. We aimed to examine the association between perioperative fluid administration and postoperative complications.

METHODS

We studied 168 pancreaticoduodenectomy patients operated in 2015 (n = 93) or 2017 (n = 75) at Helsinki University Hospital. In 2015, patients received intraoperative fluids following a goal-directed approach and, in 2017, according to anesthesiologist's clinical practice (conventional fluid management). We analyzed the differences in perioperative fluid administration between the groups, specifically examining the occurrence of severe complications (Clavien-Dindo ≥ III), pancreatic fistulas, cardiovascular complications, and the length of hospital stay.

RESULTS

The goal-directed group received more intraoperative fluids than the conventional fluid management group (12.0 ml/kg/h vs. 8.3 ml/kg/h, p < 0.001). Urine output (770 ml vs. 575 ml, p = 0.004) and intraoperative fluid balance (9.4 ml/kg/h vs. 6.3 ml/kg/h, p < 0.001) were higher in the goal-directed group than in the conventional fluid management group. Severe surgical complications (19.4% vs. 38.7%, p = 0.009) as well as clinically relevant pancreatic fistulas (1.1% vs. 10.7%, p = 0.011) occurred more frequently in patients receiving conventional fluid management. Moreover, the conventional fluid management group experienced longer hospital stays (9.0 vs. 11.5 days, p = 0.02). Lower intraoperative fluid volume accompanying conventional fluid management was associated with a higher risk of severe postoperative complications compared with higher volume in the goal-directed group (odds ratio 2.58 (95% confidence interval 1.04-6.42), p = 0.041).

CONCLUSIONS

The goal-directed group experienced severe complications less frequently. Our findings indicate that optimizing the intraoperative fluid administration benefits patients, while adopting a too-restrictive approach represents an inferior choice.

Clinical significance of postpancreatectomy acute pancreatitis defined by the International Study Group for Pancreatic Surgery

Aim

The International Study Group for Pancreatic Surgery (ISGPS) developed a structured definition of postpancreatectomy acute pancreatitis (PPAP) in 2021. This study aimed to evaluate the clinical significance of PPAP as defined by the ISGPS criteria.

Methods

We evaluated the medical records and postoperative computed tomography (CT) findings of 247 patients who underwent pancreaticoduodenectomy. Postoperative hyperamylasemia (POH) was defined as an elevation in serum amylase levels over the upper baseline limit (≥133 U/L) on postoperative days 1 and 3. PPAP was defined as acute pancreatitis satisfying the following three requirements: POH, clinically relevant deterioration, and radiologic features consistent with acute pancreatitis.

Results

Postoperative hyperamylasemia and PPAP were prevalent in 9.7% (24/247) and 3.6% (9/247) of the patients, respectively. PPAP grade B occurred in eight patients, seven of whom experienced Clavien-Dindo grade IIIA complications, including postoperative pancreatic fistula (POPF) and extended periods of postoperative hospitalization. PPAP grade C occurred in one patient, who died from the exacerbation of underlying interstitial pneumonia following the POPF occurrence. Acute pancreatitis determined by CT was observed in 15.3% (38/247) of the patients who underwent pancreaticoduodenectomy and was strongly associated with severe morbidity (P < .0001) and longer postoperative hospitalization (P < .0001). POH preceded acute pancreatitis on CT in only 23.7% (9/38) of those cases, resulting in a low incidence rate of PPAP.

Conclusion

Post-pancreatectomy acute pancreatitis is a major postoperative complication of pancreatic resection; however, based on the current ISGPS criteria, its prevalence is low. Defining PPAP promotes universal evaluation and understanding of this new concept.

Impact of spleen preservation on the incidence of postoperative pancreatic fistula after distal pancreatectomy: Is less more?

BACKGROUND

Postoperative pancreatic fistula (POPF) remains a major complication after distal pancreatectomy (DP) with a significant impact on patients' quality of life. There is limited evidence that preservation of the spleen reduces the risk of POPF. Therefore, we aimed to investigate the impact of splenectomy on perioperative outcome.

METHODS

Data from patients who underwent DP for malignant and benign disease at our institution between 2004 and 2021 were reviewed. Patients were grouped according to spleen preservation (SP-DP) and splenectomy (DPS). Intraoperative parameters and postoperative outcomes were compared between groups. Univariable and multivariable analyses were used to investigate factors that influence the occurrence of clinically relevant (cr)POPF.

RESULTS

A total of 199 patients were included, of whom 61 (30.7%) patients underwent SP-DP. Patients who underwent SP-DP had a significantly lower rate of crPOPF (p = 0.022), shorter hospital stay (p = 0.003), and less readmissions (p = 0.012). On multivariate analysis, obesity (OR 2.88, p = 0.021), benign lesions (OR 2.35, p = 0.018), postoperative acute pancreatitis (OR 2.53, p = 0.028), and splenectomy (OR 2.83, p = 0.011) were independent risk factors associated with the onset of crPOPF.

DISCUSSION

Preservation of the spleen reduces the risk of crPOPF in patients undergoing distal pancreatectomy for benign and malignant disease.

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.

Serum lipase on postoperative day one is a strong predictor of clinically relevant pancreatic fistula after pancreaticoduodenectomy: A retrospective cohort

BACKGROUND

Increased postoperative serum amylase has been recently reported to be associated with increased postoperative morbidity, but studies on postoperative serum lipase are limited. The aim of this study was to evaluate the value of postoperative serum lipase in predicting clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy (PD).

METHOD

A retrospective analysis was performed on 212 patients who underwent PD from September 2018 and March 2021, focusing on the association between postoperative day (POD) 1 serum lipase and CR-POPF.

RESULTS

Overall, 108 (50.9%) patients had elevated serum lipase levels (>68 U/L) on POD 1. Patients with elevated serum lipase exhibited a significantly higher incidence of CR-POPF (37.0% vs. 6.7%, p < 0.001). Receiver operating characteristic (ROC) analyses showed improved diagnostic accuracy for POD 1 serum lipase compared with POD 1 serum amylase in predicting CR-POPF (AUC: 0.801 vs. 0.745, p = 0.029). Elevated serum lipase on POD 1 and elevated serum CRP on POD 3 were identified as independent predictors of CR-POPF. A simple early postoperative model, consisting of POD 1 serum lipase levels and POD 3 serum CRP levels, showed good discrimination (AUC 0.76, 95% CI 0.69-0.83) to identify the onset of CR-POPF.

CONCLUSION

Serum lipase on POD 1 outperformed serum amylase on POD 1 in predicting CR-POPF after PD. The combination of POD 1 serum lipase and POD 3 serum CRP provides a reliable predicting model for CR-POPF.

Risk Factors and Clinical Impacts of Post-Pancreatectomy Acute Pancreatitis After Pancreaticoduodenectomy: A Single-Center Retrospective Analysis of 298 Patients Based on the ISGPS Definition and Grading System

Background

The definition and grading system of post-pancreatectomy acute pancreatitis (PPAP) has recently been proposed by ISGPS. This study aimed to put this definition and classification into practice and investigate the potential risk factors and clinical impacts of PPAP.

Methods

Demographic and perioperative data of consecutive patients who underwent pancreaticoduodenectomy (PD) from January 2019 to July 2021 were collected and analyzed retrospectively. The diagnostic criteria of PPAP published by ISGPS, consisting of biochemical, radiologic, and clinical parameters, were adopted. The risk factors were analyzed by univariate and multivariate analyses.

Results

A total of 298 patients were enrolled in this study, and the total incidence of PPAP was 52.4% (150 patients). Stratified by clinical impacts of PPAP, the incidences of grades B and C PPAP were 48.9% and 3.5%, respectively. PPAP after PD was significantly associated with pancreatic fistula and other unfavorable complications. Soft pancreatic texture (OR 3.0) and CRP ≥ 180 mg/L (OR 3.6) were the independent predictors of PPAP, AUC 0.613. Stratified by the grade of PPAP, soft pancreatic texture (OR 2.7) and CRP ≥ 180 mg/L (OR 3.4) were the independent predictors of grade B PPAP, and soft pancreatic texture (OR 19.3), operation duration >360 min (OR 13.8), and the pancreatic anastomosis by using conventional duct to mucosa methods (OR 10.4) were the independent predictors of grade C PPAP. PPAP complicated with pancreatic fistula significantly increased the severe complications and mortality compared to only PPAP occurrence.

Conclusion

PPAP was not an uncommon complication after PD and was associated with unfavorable clinical outcomes, especially since it was complicated with pancreatic fistula. Soft pancreatic texture and CRP ≥ 180 mg/L were the independent predictors of PPAP. Higher-volume multicenter and prospective studies are strongly needed.

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

BACKGROUND

The association between postoperative serum hyperamylasaemia (POH) and morbidity has been hypothesized but rarely explored once occurring with or without (POH-exclusive) a combined postoperative pancreatic fistula (POPF).

METHODS

Analysis of patients who consecutively underwent pancreaticoduodenectomy from 2016 to 2020. POH was defined as serum amylase activity greater than the institutional upper limit of normal (52 U/L), persisting within the first 48 hours postoperatively (postoperative day [POD] 1 and 2).

RESULTS

Among 852 patients, 15.8% developed POH-exclusive. Compared with patients without POH or POPF (64.3%), they showed a significantly higher postoperative burden (Clavien-Dindo ≥II: 52.6% vs 30.8%) with increased rates of bacteraemia (12.6% vs 6%), pleural effusion (13.3% vs 5.3%), postpancreatectomy haemorrhage (13.3% vs 7.5%), postpancreatectomy acute pancreatitis (PPAP) (10.3% vs 0%), and organ site infections (18.5% vs 10.9%; all P < .05). A total of 13.8% experienced POH with POPF leading to the worse outcome. The combined occurrence of POH with POPF led to a shorter median time to morbidity (3 PODs, 95% confidence interval [CI] 2.2-3.7 vs 6 PODs, 95% CI 4.2-8; P < .001) than patients experiencing POPF-exclusive (5.9%). In all, 46.6% of POH patients developed POPF. Body mass index (BMI) (odds ratio [OR] 1.1), male sex (OR 2.1), increased drain fluid amylase on POD 1 (OR 1.001), and increased C-reactive protein (OR 1.01) were independent risk factors for POPF once POH has occurred.

CONCLUSION

POH has relevant postoperative clinical implications, independently from POPF occurrence. Developing POH with POPF leads to an earlier onset of higher postoperative burdens. Once POH is diagnosed, risk factors for additional POPF could identify patients who may benefit from additional surveillance, specific drains protocols, and preventive strategies.

State-of-the-art surgical treatment of IPMNs

Background

A “pandemic” of incidentally discovered pancreatic cyst neoplasms (PCNs) is ongoing. Among PCNs, intraductal papillary mucinous cystic neoplasms (IPMNs) are the most common and with their complex biology could represent a precursor lesion of pancreatic cancer. Although multiple guidelines exist to guide their treatment, there are still many “gray areas” on indications for surgery for IPMNs.

Methods

The current indications for surgery of IPMNs were reappraised, considering potential discrepancies between available evidence and guidelines policies. The practice at a high-volume center for the diagnosis and treatment of PCN was presented and discussed.

Results

Most IPMNs do not and will never require surgery, as they won’t progress to malignancy. The current literature is solid in identifying high-grade dysplasia (HGD) as the right and timely target for IPMN resection, but how to precisely assess its presence remains controversial and guidelines lack of accuracy in this regard. Multiple tumorigenic pathways of progression of IPMNs exist, and their knowledge will likely lead to more accurate tests for malignancy prediction in the future.

Conclusions

The surgical management of IPMNs still is a matter of debate. Indication for resection should be considered only in highly selected cases with the ideal target of HGD. Clinicians should critically interpret the guidelines’ indications, refer to a multidisciplinary team discussion, and always consider the outcome of an adequate counselling with the patient.