Elevation of urine trypsinogen 2 is an independent risk factor for pancreatic fistula after pancreaticoduodenectomy

Postoperative pancreatitis and pancreatic fistulae: a review of current evidence

OBJECTIVES

Postoperative pancreatic fistula (POPF) represents one of the most severe complications following pancreatic surgery. Despite being a leading cause of morbidity and mortality, its pathophysiology is poorly understood. In recent years, there has been growing evidence to support the role of postoperative or post-pancreatectomy acute pancreatitis (PPAP) in the development of POPF. This article reviews the contemporary literature on POPF pathophysiology, risk factors, and prevention strategies.

METHODS

A literature search was conducted using electronic databases, including Ovid Medline, EMBASE, and Cochrane Library, to retrieve relevant literature published between 2005 and 2023. A narrative review was planned from the outset.

RESULTS

A total of 104 studies fulfilled criteria for inclusion. Forty-three studies reported on technical factors predisposing to POPF, including resection and reconstruction technique and adjuncts for anastomotic reinforcement. Thirty-four studies reported on POPF pathophysiology. There is compelling evidence to suggest that PPAP plays a critical role in the development of POPF. The acinar component of the remnant pancreas should be regarded as an intrinsic risk factor; meanwhile, operative stress, remnant hypoperfusion, and inflammation represent common mechanisms for acinar cell injury.

CONCLUSIONS

The evidence base for PPAP and POPF is evolving. Future POPF prevention strategies should look beyond anastomotic reinforcement and target underlying mechanisms of PPAP development.

A Simple Classification of Pancreatic Duct Size and Texture Predicts Postoperative Pancreatic Fistula: A classification of the International Study Group of Pancreatic Surgery

OBJECTIVE

The aim of this study was to develop a classification system for pancreas-associated risk factors in pancreatoduodenectomy (PD).

SUMMARY BACKGROUND DATA

Postoperative pancreatic fistula (POPF) is the most relevant PD-associated complication. A simple standardized surgical reporting system based on pancreas-associated risk factors is lacking.

METHODS

A systematic literature search was conducted to identify studies investigating clinically relevant (CR) POPF (CR-POPF) and pancreas-associated risk factors after PD. A meta-analysis of CR-POPF rate for texture of the pancreas (soft vs not-soft) and main pancreatic duct (MPD) diameter was performed using the Mantel-Haenszel method. Based on the results, the International Study Group of Pancreatic Surgery (ISGPS) proposes the following classification: A, not-soft (hard) texture and MPD >3 mm; B, not-soft (hard) texture and MPD ≤3 mm; C, soft texture and MPD >3 mm; D, soft texture and MPD ≤3 mm. The classification was evaluated in a multi-institutional, international cohort.

RESULTS

Of the 2917 articles identified, 108 studies were included in the analyses. Soft pancreatic texture was significantly associated with the development of CR-POPF [odds ratio (OR) 4.24, 95% confidence interval (CI) 3.67-4.89, P < 0.01) following PD. Similarly, MPD diameter ≤3 mm significantly increased CR-POPF risk compared with >3 mm diameter MPDs (OR 3.66, 95% CI 2.62-5.12, P < 0.01). The proposed 4-stage system was confirmed in an independent cohort of 5533 patients with CR-POPF rates of 3.5%, 6.2%, 16.6%, and 23.2% for type A-D, respectively ( P < 0.001).

CONCLUSION

For future pancreatic surgical outcomes studies, the ISGPS recommends reporting these risk factors according to the proposed classification system for better comparability of results.

[Postoperative pancreatitis after pancreatoduodenectomy]

OBJECTIVE

Retrospective assessment of the influence of postoperative pancreatitis in development of pancreatic fistula.

MATERIAL AND METHODS

The study included 173 patients after pancreatoduodenectomy performed between 2016 and 2019. Postoperative pancreatitis within the 1^st postoperative day was verified considering blood amylase > 125 U/L. Patients with postoperative pancreatitis (n=36) were included in the main group, the control group consisted of 137 patients without pancreatitis. Postoperative pancreatic fistula was determined according to the ISGPS 2016 classification. Statistical analysis of the effect of postoperative pancreatitis on development of pancreatic fistula was carried out using relative risk and odds ratio with 95% confidence interval in both groups.

RESULTS

Postoperative pancreatitis occurred in 36 (20.8%) out of 173 patients after pancreatoduodenectomy. Pancreatic fistula occurred in 18 (50%) cases. Among 137 patients without postoperative pancreatitis, only 18 (13.1%) patients developed severe pancreatic fistula. Relative risk was 3.8 (95% CI 2.22-6.51, p<0.0001), odds ratio - 6.6 (95% CI 2.91-15.01, p<0.0001).

CONCLUSION

Postoperative pancreatitis significantly influences development of severe pancreatic fistula.

Systematic review and meta-analysis of factors associated with post-operative pancreatic fistula following pancreatoduodenectomy

BACKGROUND

Many studies have explored factors relating to post-operative pancreatic fistula (POPF); however, the original definition (All-POPF) was revised to include only 'clinically relevant' (CR) POPF. This study identified variables associated with the two International Study Group on Pancreatic Surgery definitions to identify which variables are more strongly associated with CR-POPF.

METHODS

A systematic review identified all studies reporting risk factors for POPF (using both International Study Group on Pancreatic Fistula definitions) following pancreatoduodenectomy. The primary outcome was factors associated with CR-POPF. Meta-analyses (random effects models) of pre-, intra- and post-operative factors associated with POPF in more than two studies were included.

RESULTS

Among 52 774 patients All-POPF (n = 69 studies) and CR-POPF (n = 53 studies) affected 27% (95% confidence interval (CI_95% ) 23-30) and 19% (CI_95% 17-22), respectively. Of the 176 factors, 24 and 17 were associated with All- and CR-POPF, respectively. Absence of pre-operative pancreatitis, presence of renal disease, no pre-operative neoadjuvant therapy, use of post-operative somatostatin analogues, absence of associated venous or arterial resection were associated with CR-POPF but not All-POPF.

CONCLUSION

In conclusion this study demonstrates wide variation in reported rates of POPF and that several risk factors associated with CR-POPF are not used within risk prediction models. Data from this study can be used to shape future studies, research and audit across ethnic and geographic boundaries in POPF following pancreatoduodenectomy.

The management of intra-abdominal infections from a global perspective: 2017 WSES guidelines for management of intra-abdominal infections

Intra-abdominal infections (IAIs) are common surgical emergencies and have been reported as major contributors to non-trauma deaths in the emergency departments worldwide. The cornerstones of effective treatment of IAIs are early recognition, adequate source control, and appropriate antimicrobial therapy. Prompt resuscitation of patients with ongoing sepsis is of utmost important. In hospitals worldwide, non-acceptance of, or lack of access to, accessible evidence-based practices and guidelines result in overall poorer outcome of patients suffering IAIs. The aim of this paper is to promote global standards of care in IAIs and update the 2013 WSES guidelines for management of intra-abdominal infections.

Defining post-operative pancreatitis as a new pancreatic specific complication following pancreatic resection

INTRODUCTION

Post-operative pancreatic fistula has been well defined. However the underlying aetiology remains poorly understood. The aim of this review was to investigate whether the underlying aetiology for a proportion of patients suffering from post-operative pancreatic fistula was due to post-operative pancreatitis.

METHOD

A systematic literature review according to the PRISMA guidelines. The date range was from 2005 to 2016. The search strategy included the terms: post-operative pancreatitis, pathophysiology, post-operative pancreatic fistula, pancreaticoduodenectomy, ischaemic pancreatitis, microcirculation and pancreatitis, serum and drain amylase and lipase. The data was summarised without quantitative or qualitative analysis.

RESULTS

There exists significant physiological, biochemical, clinical and histological evidence in the literature that a proportion of post-operative pancreatic fistula is due to post-operative pancreatitis. A new definition of post-operative pancreatitis based on the presence of biochemical evidence for pancreatic inflammation (urinary trypsinogen-2 >50 ug/L or serum amylase/lipase > upper limit of normal) between post-operative days 0-2. Predicted severity is based on C-reactive protein with a cut-off of 180 mg/L at post-operative day 2. The proposed grading of severity is in line with previous work by international study group of pancreatic surgery.

CONCLUSION

Post-operative pancreatitis should be recognised as a separate pancreatic specific complication following pancreatic resection. Improved recognition may allow better understanding of potential methods of prevention, treatment and prediction of severity.

Preoperative diabetes as a protective factor for pancreatic fistula after pancreaticoduodenectomy: a meta-analysis

BACKGROUND

The role of diabetes mellitus (DM) in pancreatic fistula (PF) or clinical relevant PF (CR-PF) after pancreaticoduodenectomy (PD) or pylorus-preserving pancreaticoduodenectomy (PPPD) is unclear. We conducted a meta-analysis to investigate the relationship between DM and PF or CR-PF.

DATA SOURCES

Embase, MEDLINE and Cochrane databases were searched systematically for relevant articles from January 2005 to June 2013. The selected studies that examined clinical risk factors of PF or CR-PF were included. We created pooled estimates for our outcomes using the random-effects model.

RESULTS

Sixteen observational clinical studies were included. Pooling of PF rates from ten studies revealed that DM was associated with a decreased risk of PF (P=0.01). CR-PF rates from 8 studies showed no significant difference between DM and control group (P=0.14).

CONCLUSIONS

DM is not a risk factor for PF in patients undergoing PD or PPPD. On the contrary, patients without DM are at a higher risk of PF because the pancreases in these patients have more fatty tissue and the pancreas is soft.

Internal compared with external drainage of pancreatic duct during pancreaticoduodenectomy: a retrospective study

OBJECTIVE

To compare internal with external drainage of the pancreatic duct during pancreaticoduodenectomy with regard to the incidence of postoperative pancreatic fistula (POPF) and other complications.

METHODS

We retrospectively analyzed 316 patients who underwent pancreaticoduodenectomy with a placed drainage tube (external, n=128; internal, n=188) in the pancreatic duct from 1 January 1999 to 31 December 2011 in Tianjin Third Central Hospital of China. The incidence of POPF and some other complications were compared.

RESULTS

There was no difference in the incidence rates of POPF between those given an internal or external drainage tube (P=0.788), but POPF was more severe in the former (P=0.014). Intraperitoneal bleeding rate was also higher in the patients with internal drainage (P=0.040), but operative time and postoperative hospitalization were longer in those with external drainage (P=0.002 and P=0.007, respectively). There was no difference between the groups with regard to the incidence rates of gastrointestinal bleeding, delayed gastric emptying, pulmonary infection, or incision infection and in-hospital mortality.

CONCLUSIONS

External drainage of the pancreatic duct during pancreaticoduodenectomy can decrease the severity of POPF, but operative time and postoperative hospitalization will be extended.

Serum amylase on the night of surgery predicts clinically significant pancreatic fistula after pancreaticoduodenectomy

OBJECTIVES

Drainage after pancreaticoduodenectomy (PD) remains controversial because the risk for uncontrolled postoperative pancreatic fistula (POPF) must be balanced against the potential morbidity associated with prolonged and possibly unnecessary drainage. This study investigated the utility of the level of serum amylase on the night of surgery [postoperative day (PoD) 0 serum amylase] to predict POPF.

METHODS

A total of 185 patients who underwent PD were studied. Occurrences of POPF were graded using the International Study Group on Pancreatic Fistula (ISGPF) classification. Receiver operating characteristic (ROC) analysis identified a threshold value of PoD 0 serum amylase associated with clinically significant POPF (ISGPF Grades B and C) in a test cohort (n = 45). The accuracy of this threshold value was then tested in a validation cohort (n = 140).

RESULTS

Overall, 43 (23.2%) patients developed clinically significant POPF. The threshold value of PoD 0 serum amylase for the identification of clinically significant POPF was ≥ 130 IU/l (P = 0.003). Serum amylase of <130 IU/l had a negative predictive value of 88.8% for clinically significant POPF (P < 0.001). Serum amylase of ≥ 130 IU/l on PoD 0 and a soft pancreatic parenchyma were independent risk factors for clinically significant POPF.

CONCLUSIONS

Postoperative day 0 serum amylase of <130 IU/l allows for the early and accurate categorization of patients at least risk for clinically significant POPF and may identify patients suitable for early drain removal.

Pancreatic fistula after central pancreatectomy: case series and review of the literature

BACKGROUND

Postoperative pancreatic fistula is one of the most common complications after pancreatectomy. This study aimed to assess the occurrence and severity of pancreatic fistula after central pancreatectomy.

METHODS

The medical records of 13 patients who had undergone central pancreatectomy were retrospectively studied, together with a literature review of studies including at least five cases of central pancreatectomy. Pancreatic fistula was defined and graded according to the recommendations of the International Study Group on Pancreatic Fistula (ISGPF).

RESULTS

No death was observed in the 13 patients. Pancreatic fistula developed in 7 patients and was successfully treated non-operatively. None of these patients required re-operation. A total of 40 studies involving 867 patients who underwent central pancreatectomy were reviewed. The overall pancreatic fistula rate of the patients was 33.4% (0-100%). Of 279 patients, 250 (89.6%) had grade A or B fistulae of ISGPF and were treated non-operatively, and the remaining 29 (10.4%) had grade C fistulae of ISGPF. In 194 patients, 15 (7.7%) were re-operated upon. Only one patient with grade C fistula of ISGPF died from multiple organ failure after re-operation.

CONCLUSION

Despite the relatively high occurrence, most pancreatic fistulae after central pancreatectomy are recognized a grade A or B fistula of ISGPF, which can be treated conservatively or by mini-invasive approaches.

Indicators for proper management of surgical drains following pancreaticoduodenectomy

BACKGROUND

The indicators for proper drain management following pancreaticoduodenectomy (PD) remain unclear. Our aim was to identify appropriate timing and proper indicators for safe drain management after PD.

METHODS

Prospectively collected data from 200 patients who underwent PD were evaluated. Postoperative clinical factors for clinically relevant pancreatic fistulas (CR-POPFs) and management of surgically placed drains were analyzed retrospectively.

RESULTS

CR-POPFs occurred in 8% of patients. By logistic regression analysis, one factor (non-serous fluid in the drain) on postoperative day (POD) 1 and two factors (non-serous fluid in the drain and serum CRP levels) on POD 3 and 4 were significantly associated with CR-POPFs. Receiver operating characteristic analysis demonstrated that combined predictive factors on POD 4 were the most accurate. Of 163 patients with serous fluid in the drain and CRP <15.6 mg/dl on POD 4, 1% had CR-POPFs, but no patient required POPF-related re-drainage. In contrast, among 37 patients with non-serous fluid in the drain or CRP levels ≥15.6 mg/dl, 35% had CR-POPFs, and 8% required POPF-related re-drainage.

CONCLUSIONS

A combination of CRP levels and the color of surgical drain fluid, not POD1 or 3, but on POD 4, may be the most accurate indicators for safe drain management following PD.