Assessing Intra-abdominal status for clinically relevant postoperative pancreatic fistula based on postoperative fluid collection and drain amylase levels after distal pancreatectomy

Abstract

Aim: The aim of this study was to evaluate the intra-abdominal status related to postoperative pancreatic fistula by combining postoperative fluid collection and drain amylase levels.

Methods: We retrospectively reviewed the data of 203 patients who underwent distal pancreatectomy and classified their postoperative abdominal status into four groups based on postoperative fluid collection size and drain amylase levels. We also evaluated the incidence of clinically relevant postoperative pancreatic fistula in each group according to C-reactive protein values.

Results: The incidence of clinically relevant postoperative pancreatic fistula in the entire cohort (n = 203) was 28.1%. Multivariate analysis revealed that postoperative fluid collection, drain amylase levels, and C-reactive protein levels are considerable risk factors for clinically relevant postoperative pancreatic fistula. In the subgroup with large postoperative fluid collection and high drain amylase levels, 65.9% of patients developed clinically relevant postoperative pancreatic fistula. However, no significant difference was observed in C-reactive protein levels between patients with clinically relevant postoperative pancreatic fistula and those without it. In contrast, in the subgroup with a large postoperative fluid collection size or a high amylase level alone, a significant difference was observed in C-reactive protein values between the patients with clinically relevant postoperative pancreatic fistula and those without it.

Conclusion: Postoperative fluid collection status and the C-reactive protein value provide a more precise assessment of intra=abdominal status related to postoperative pancreatic fistula after distal pancreatectomy. This detailed analysis may be a clinically reasonable approach to individual drain management.

Keywords: amylase; analysis; pancreatectomy; pancreatic fistula; patients.

FIGURE 1

(A) The diagram illustrates the vertical assessment method employed to evaluate postoperative fluid collections (PFCs) and peritoneal depth. (B–E) Representative computed tomography images were used to evaluate the horizontal extent of continuous fluid accumulation from the pancreatic stumps. (B) The absence of consistent fluid retention at the pancreatic stump was classified as H0. (C) The confinement of PFCs to the perimeter of the superior mesenteric artery was classified as H1. (D) The spread of PFCs to the prerenal fat was classified as H2. (E) The extension of PFCs to the left subdiaphragm was classified as H3.

FIGURE 2

(A) The relationship between the vertical and horizontal distribution of postoperative fluid collections. (B) Receiver operating characteristic curve analysis was utilized to assess the predictive value of maximum vertical diameter (V max), drain amylase levels on postoperative day 3, and C‐reactive protein (CRP) on postoperative day 7 in detecting clinically relevant postoperative pancreatic fistula (CR‐POPF).

FIGURE 3

(A) The cases were sorted into four groups according to preestablished threshold values for V max of PFCs and drain amylase levels on postoperative day 3. Cases with CR‐POPF and those without it are depicted with black and white points, respectively. (B) The violin plot compares the CRP levels on postoperative day 7 between cases with and without CR‐POPF in the four groups classified based on the cutoff values of V max of PFCs and drain amylase levels on postoperative day 3, as shown in Figure 3(A). The interquartile range is also included.