Risk Factors for Postoperative Pancreatic Fistula in Distal Pancreatectomy

The pancreas-to-muscle signal intensity ratio on T1-weighted MRI as a predictive biomarker for postoperative pancreatic fistula after distal pancreatectomy: a single-center retrospective study

BACKGROUND

Postoperative pancreatic fistula (POPF) is one of the serious complications of pancreatic surgery. When POPF occurs and becomes severe, it causes secondary complications and a longer treatment period. We previously reported a correlation between pancreatic fibrosis and magnetic resonance imaging (MRI) findings, and MRI may have the potential to predict POPF. This study aimed to assess the predictive ability of the pancreas-to-muscle signal intensity ratio on T₁-weighted MRI (SIR on T₁-w MRI) for POPF after distal pancreatectomy (DP).

METHODS

This single-institution retrospective study comprised 117 patients who underwent DP. It was conducted between 2010 and 2021 at the Gifu University Hospital. We statistically analyzed pre-, intra-, and postoperative factors to assess the correlation with POPF.

RESULTS

According to the definition and grading of the International Study Group of Pancreatic Fistula (ISGPF), 29 (24.8%) of the 117 patients had POPF grades B and C. In the univariate analysis, POPF was significantly associated with the pancreas-to-muscle SIR on T₁-w MRI, the drainage fluid amylase concentration (D-Amy) levels on postoperative day (POD) 1 and 3, white blood cell count on POD 1 and 3, C-reactive protein level on POD 3, and heart rate on POD 3. In multivariate analysis, only the pancreas-to-muscle SIR on T₁-w MRI (>1.37; odds ratio [OR] 23.25; 95% confidence interval [CI] 3.93-454.03; p < 0.01) and D-Amy level on POD 3 (>737 U/l; OR 3.91; 95% CI 1.02-16.36; p = 0.046) were identified as independent predictive factors.

CONCLUSIONS

The pancreas-to-muscle SIR on T₁-w MRI and postoperative D-Amy levels were able to predict the development of POPF after DP. The pancreas-to-muscle SIR on T₁-w MRI may be a potential objective biomarker reflecting pancreatic status.

Early Predictive Factors for Postoperative Pancreatic Fistula After Distal Pancreatectomy for Pancreatic Cancer

BACKGROUND/AIM

Postoperative pancreatic fistula (POPF) is the most serious complication of distal pancreatectomy (DP). When POPF occurs and becomes severe, it causes secondary complications and leads to a longer treatment period. This study aimed to identify early predictive factors of POPF after DP for pancreatic cancer (PC).

PATIENTS AND METHODS

This retrospective, single-institution study comprised of 55 patients with PC who underwent DP between 2010 and 2021 at the Gifu University Hospital. We statistically analyzed pre-, intra-, and post-operative factors to identify early predictive factors for POPF.

RESULTS

According to the definition and grading of the International Study Group of Pancreatic Fistula (ISGPF), 12 (21.8%) of 55 patients had POPF grades B and C. In the univariate analysis, POPF was significantly associated with the pancreas-to-muscle signal intensity ratio on T ₁ -weighted magnetic resonance imaging (SIR on T ₁ -w MRI), the drainage fluid amylase (D-Amy) levels on postoperative day 3 (POD3), C-reactive protein (CRP) on POD3, and heart rate on POD3. In multivariate analysis, pancreas-to-muscle SIR on T ₁ -w MRI [>1.37; odds ratio (OR)=17.08; 95% confidence interval (CI)=1.64-598.16; p=0.02], D-Amy levels on POD3 (>1,200 U/l; OR=20.00; 95% CI=1.73-563.83; p=0.02) and heart rate on POD3 (>100 bpm; OR=15.33; 95% CI=1.53-258.45; p=0.02) were identified as independent early predictive factors.

CONCLUSION

Preoperative pancreas-to-muscle SIR on T ₁ -w MRI and postoperative D-Amy levels and heart rate significantly correlated with POPF after DP for PC. Postoperative management based on these predictive factors may improve the postoperative course.

Reduction in post-operative pancreatic fistula with polyethylene glycol and recombinant human albumin sealant following stapled distal pancreatectomy

BACKGROUND

Postoperative pancreatic fistula (POPF) remains a significant cause of morbidity in patients undergoing distal pancreatectomy (DP). The use of polyethylene glycol (PEG) and recombinant human albumin sealant gel applied to the transected pancreatic margin in DP may reduce POPF rates and was assessed.

METHODS

A retrospective single centre cohort study of patient undergoing DP at an Australian high volume tertiary institution between January 2015 and January 2021. Rates of POPF in patients undergoing stapled pancreatic transection with PEG sealant were compared to other methods.

RESULTS

A total of 54 cases were identified for analysis, with 16 undergoing stapled DP combined with staple line application of PEG (PEG group). Most patients in the control group had stapled DP 92% (35 of 38), with 47% (18 of 38) combined with a reinforcing buttress, with or without the use other glue types. Overall, 28 of 54 (52%) developed a POPF, with a significantly lower rate in the PEG group (3 of 16 vs. 25 of 38 in the Control group; p = 0.003). Clinically significant Grade B/C POPF was lower in the PEG group (0 of 16 vs. 9 of 28 in the Control group; p = 0.045), and patients in the PEG group had a shorter median (range) length of hospital stay (6 [4-14] days vs. 10 [6-41] days p = 0.04).

CONCLUSION

Stapled DP with the application of PEG and recombinant human albumin sealant to the transection line appears to be associated with a lower rate of clinically significant POPF.

Distal Pancreatic Resection with Splenectomy in the Rat: A Pancreatic Fistula Model to Investigate Postsurgical Damage?

BACKGROUND

Postoperative pancreatic fistula (POPF) is a major complication in pancreatic surgery and can cause considerable postoperative morbidity. Advanced surgical-technical approaches to prevent POPF did not yield a substantial improvement. To investigate innovative treatments, experimental animal models of distal pancreatic resection and pancreaticoduodenectomy are of fundamental importance. After a failed attempt to replicate a previously described rat model for pancreatic fistula induction, we proceeded to distal pancreatic resection with splenectomy to provoke pancreatic leakage and generate a suitable animal model.

METHODS

Distal pancreatic resection with splenectomy was performed in 40 rats. The rats were sacrificed on postoperative day (POD) 1, 2, 4, 6, 8, or 10, and the abdominal cavity was explored. Ascites probes were collected pre- and postoperatively for the detection of pancreas amylase and lipase. Tissue samples from the naïve pancreas (POD 0) and the postoperatively harvested remnant were evaluated histologically. The extent of necrosis was determined, and samples were examined for neutrophil infiltration. TUNEL staining served for the verification of necrosis in distinct cases. Immunohistochemistry of Ki67, von Willebrand factor, and CD68 was performed to evaluate proliferation, blood-vessel sprouting, and macrophage invasion.

RESULTS

The rats showed no clinical symptoms or severe complications in the postoperative course up to 10 days. Abdominal exploration revealed adhesions in the upper abdomen, but no intra-abdominal fluid accumulations were found. Signs of inflammation and tissue damage were evident at the pancreatic resection margin on histological examination whereas the naïve pancreatic tissue was widely unaffected. Statistically significant differences were seen between the preoperative and postoperative extent of necrosis, the presence of neutrophil infiltrate, and levels of ascitic amylase and lipase. Immunohistochemical staining on Ki67, von Willebrand factor, and CD68 did not reveal any workable results on nonstatistical examination, and it was therefore not considered for further analyses.

CONCLUSION

Creating a functional animal model of pancreatic fistula that reflects the clinical and pathophysiological impact of pancreatic leakage in humans has not been achieved. Our approach of left pancreatic resection recapitulated inflammation and tissue damage, early events in the development of fistulas, and it could be suitable for the experimental testing of novel targeting methods.

Association between intraoperative and postoperative epidural or intravenous patient-controlled analgesia and pancreatic fistula after distal pancreatectomy

PURPOSE

This study aimed to elucidate the association between postoperative pancreatic fistula (POPF) after distal pancreatectomy (DP) and clinicopathological factors and intraoperative and postoperative epidural or intravenous patient-controlled analgesia (IV-PCA).

METHODS

We reviewed data of 116 patients who underwent distal pancreatectomy at Gunma University Hospital from October 2000 to October 2019. Clinical POPF was defined as the International Study Group of Pancreatic Fistula grade B or C.

RESULTS

Intraoperative and postoperative analgesia included fentanyl-mediated IV-PCA (n = 37, 32%), fentanyl-mediated epidural analgesia (n = 39, 34%), and morphine-mediated epidural analgesia (n = 40, 34%). All patients had received analgesia. Clinical POPF occurred in 34 of the 116 (29%) DP cases. Male sex (P = 0.035) and the length of operation time (P = 0.0070) were significant risk factors of clinical POPF. Furthermore, a thick pancreas was more likely to cause clinical POPF than a thin one (P = 0.052). No statistically significant difference was found between other factors, including intraoperative and postoperative analgesia (P = 0.95), total median oral morphine equivalents (P = 0.23), and clinical POPF.

CONCLUSION

Intraoperative and postoperative epidural analgesia and IV-PCA are not associated with clinical POPF after DP. Our results suggest that morphine and fentanyl can be used as IV-PCA or epidural analgesia.

Pancreatic stump closure techniques and pancreatic fistula formation after distal pancreatectomy: Meta-analysis and single-center experience

Background

Pancreatic fistula/PF is the most frequent and feared complication after distal pancreatectomy/DP. However, the safest technique of pancreatic stump closure remains an ongoing debate. Here, we aimed to compare the safety of different pancreatic stump closure techniques for preventing PF during DP.

Methods

We performed a PRISMA-based meta-analysis of all relevant studies that compared at least two techniques of stump closure during DP with regard to PF rates/PFR. We further performed a retrospective analysis of our institutional PFR in correlation with stump closure techniques.

Results

8301 studies were initially identified. From these, ten randomized controlled trials/RCTs, eleven prospective and 59 retrospective studies were eligible. Stapler closure (26%vs.31%, OR:0.73, p = 0.02), combination of stapler and suture (30%vs.33%, OR:0.70, p = 0.05), or stump anastomosis (14%vs.28%, OR:0.51, p = 0.02) were associated with lower PFR than suture closure alone. Spleen preservation/splenectomy, or laparoscopic/open DP, TachoSil^®, fibrin-like glue-application, or bioabsorbable-stapler-reinforcements (Seamguard^®) did not influence PFR after DP. In contrast, autologous patches (falciform ligament/seromuscular patches) resulted in lower PFR than no patch application (21.9%vs.25,8%, OR:0.60, p = 0.006). In our institution, the major three techniques of stump closure resulted in comparable PFR (suture:27%, stapler:29%, or combination:24%). However, selective suturing/clipping of the main pancreatic duct during pancreatic stump closure prevented severe PF (p = 0.02).

Conclusion

After DP, stapler closure, pancreatic anastomosis, or falciform/seromuscular patches lead to lower PFR than suture closure alone. However, the differences are rather small, and further RCTs are needed to test these effects. Selective closure of the main pancreatic duct during stump closure may prevent severe PF.

Reproducibility of preoperative endoscopic injection of botulinum toxin into the sphincter of Oddi to prevent postoperative pancreatic fistula

Background

A postoperative pancreatic fistula (POPF) is the most common and potentially life-threatening surgical complication in pancreatic surgery. One possible pharmacological treatment could be the endoscopic injection of botulinum toxin (BTX) into the sphincter of Oddi to prevent POPF. Promising data reported a significantly reduced rate of clinically relevant POPF. We analyzed the effect of BTX injection in our patients undergoing distal pancreatectomy (DP).

Methods

A retrospective analysis of patients undergoing DP was performed. Patients with preoperative endoscopic injection of BTX into the sphincter of Oddi were included. The end points were postoperative outcomes including POPF. BTX patients were compared with a historical cohort and matched in a 1:1 ratio using a propensity score analysis.

Results

A total of 19 patients were treated with endoscopic injection of BTX before open (n=8) or laparoscopic (n=11) DP. The median age of the patients was 67 years and the mean body mass index was 25.9 kg/m². In median, the intervention was performed 1 day (range, 0–14 days) before the operation. There were no intervention-related complications. The incidence of POPF was not statistically different between the two groups: a clinically relevant POPF grade (B/C) occurred in 32% (BTX) and 42% (control; p=0.737). Likewise, there were no significant differences in postoperative drain fluid amylase levels, morbidity, and mortality.

Conclusion

The present study could not reproduce the published results of a significant lowering of grade B/C POPF. The explanations could be the timing of BTX injection before surgery and the endoscopic technique of BTX injection. However, the conflicting results after BTX injection in two high-volume centers prompt a randomized controlled multicenter trial with trained endoscopists.

Risk factors of postoperative pancreatic fistula in patients after distal pancreatectomy: a systematic review and meta-analysis

Postoperative pancreatic fistula (POPF) is a common complication following distal pancreatectomy (DP). However, the risk factors of this complication in patients after DP still remain controversial. The aim of our study is to estimate the association between potential risk factors and POPF. Relevant articles published up to June 21, 2016 were identified via PubMed, EMBASE, Web of Science, and The Cochrane Library. Studies that examined the risk factors of POPF following DP were enrolled. 20 articles (2070 patients) were finally included in this study. The pooled data suggested that patients with soft pancreas, higher Body Mass Index (BMI), blood transfusion, elevated intraoperative blood loss, and longer operative time had a decreased risk for POPF. However, age, gender, malignant pathology, types of stump closure, octreotide therapy, history of diabetes and chronic pancreatitis, splenectomy, multiorgan resection, main duct ligation, preoperative serum albumin levels, PGA felt wrapping, and extended lymphadenectomy could not be regarded as risk factors for POPF. Our analytic data demonstrated that pancreas texture, BMI, blood transfusion, intraoperative blood loss, and operative time were clinical predictor for POPF. This study may assist surgeons to screen patients with high risk of POPF and select appropriate treatment measures.

The Effect of Body Mass Index on Surgical Outcomes in Patients Undergoing Pancreatic Resection: A Systematic Review and Meta-Analysis

OBJECTIVES

Previous studies that investigated the association between body mass index (BMI) and pancreatectomy outcomes have produced conflicting conclusions. We conducted this meta-analysis to assess the association between them.

METHODS

We searched PubMed, EMBASE, and Cochrane Library databases up to December 28, 2014. Patients were divided into high-BMI group (BMI ≥ 25 kg/m) and normal-BMI group (BMI < 25 kg/m). Postoperative and intraoperative outcomes were evaluated. Meta-regression and subgroup analysis were performed to evaluate any factors accountable for the heterogeneity. Meta-analysis was performed using a random-effect model.

RESULTS

We included 22 studies involving 8994 patients. Patients in the high-BMI group had significantly increased postoperative pancreatic fistula rate (odds ratio [OR],1.96; 95% confidence interval [CI], 1.43-2.67), delayed gastric emptying rate (OR, 1.62; 95% CI, 1.15-2.29), wound infection rate (OR, 1.43; 95% CI, 1.07-1.93), operation time (mean difference [MD],15; 95% CI, 13.40-16.60), blood loss (MD, 270.71; 95% CI, 248.93-292.49), and length of hospital stay (MD, 2.87; 95% CI, 1.51-4.24). For modest heterogeneity in postoperative pancreatic fistula, regional distribution tended to be the contributor.

CONCLUSIONS

High BMI not only increased the surgical difficulty but also decreased the surgical safety for pancreatectomy.

Rapid postoperative reduction in prognostic nutrition index is associated with the development of pancreatic fistula following distal pancreatectomy

BACKGROUNDS

Despite recent advances in surgical techniques and devices for pancreatic remnant closure, postoperative pancreatic fistula (POPF) still remains one of the common complications after distal pancreatectomy (DP). Identification of risk factors for POPF may lead to the development of new strategies to prevent this ominous complication.

METHODS

We retrospectively reviewed data on 44 patients undergoing DP with the use of a stapler to identify risk factors for POPF. Study variables included preoperative prognostic nutritional index (PNI) and reduction rate of PNI on postoperative day (POD) 7.

RESULTS

POPF occurred in 23 patients (52%), of which 13 (56%) were grade B or C. Univariate analyses comparing patients with POPF and those without POPF showed significant differences in body mass index (P = 0.0102), pancreatic thickness (P = 0.0134), white blood cell count on POD7 (P = 0.0432), C-reactive protein level on POD7 (P = 0.0123), and PNI reduction rate (P = 0.0471). A multivariate analysis revealed pancreatic thickness (P = 0.0121) and PNI reduction rate (P = 0.0165) to be significant factors for POPF. Furthermore, the PNI reduction rate was significantly higher in patients with clinically relevant (grade B/C) POPF than in those with no or grade A POPF (P = 0.0257). In most patients, the massive postoperative PNI reduction preceded the diagnosis of clinically relevant POPF.

CONCLUSIONS

These findings suggest that rapid postoperative reduction in PNI is associated with the development of POPF.