Risk factors and outcomes of infected pancreatic necrosis: Retrospective cohort of 148 patients admitted to the ICU for acute pancreatitis

Organ Failure and Prediction of Severity in Acute Pancreatitis

Organ failure (OF) is a sinister development in the clinical course of acute pancreatitis, and its prediction is crucial for triaging the patient. Persistent systemic inflammatory response syndrome and raised interleukin-6 levels have a good predictive accuracy. Pathophysiology involves the release of damage-associated molecular patterns as a consequence of pancreatic injury, recruitment of inflammatory cells, and the release of proinflammatory cytokines and chemokines causing cytokine storm. Respiratory system is the most common and earliest to fail. Although a few therapeutic options are in the pipeline, renewed efforts are required to develop targeted therapies to mitigate systemic inflammation and OF.

Coagulopathy and acute pancreatitis: pathophysiology and clinical treatment

Coagulopathy is a critical pathophysiological mechanism of acute pancreatitis (AP), arising from the complex interplay between innate immune, endothelial cells and platelets. Although initially beneficial for the host, uncontrolled and systemic activation of coagulation cascade in AP can lead to thrombotic and hemorrhagic complications, ranging from subclinical abnormalities in coagulation tests to severe clinical manifestations, such as disseminated intravascular coagulation. Initiation of coagulation activation and consequent thrombin generation is caused by expression of tissue factor on activated monocytes and is ineffectually offset by tissue factor pathway inhibitor. At the same time, endothelial-associated anticoagulant pathways, in particular the protein C system, is impaired by pro-inflammatory cytokines. Also, fibrin removal is severely obstructed by inactivation of the endogenous fibrinolytic system, mainly as a result of upregulation of its principal inhibitor, plasminogen activator inhibitor type 1. Finally, increased fibrin generation and impaired break down lead to deposition of (micro) vascular clots, which may contribute to tissue ischemia and ensuing organ dysfunction. Despite the high burden of coagulopathy that have a negative impact on AP patients' prognosis, there is no effective treatment yet. Although a variety of anticoagulants drugs have been evaluated in clinical trials, their beneficial effects are inconsistent, and they are also characterized by hemorrhagic complications. Future studies are called to unravel the pathophysiologic mechanisms involved in coagulopathy in AP, and to test novel therapeutics block coagulopathy in AP.

Effectiveness and safety of low molecular weight heparin in the management of acute pancreatitis: a systematic review and meta-analysis

BACKGROUND

Recent studies suggest that low-molecular-weight heparin (LMWH) may play a role in mitigating the severity of acute pancreatitis (AP). This systematic review and meta-analysis aims to synthesise existing evidence on the effectiveness and safety of LMWH in the treatment of moderately-severe and severe AP.

METHODS

This systematic review and meta-analysis was conducted in accordance with the 2020 update of the PRISMA guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. The systematic search was conducted in MEDLINE, the Cochrane Central Register of Controlled Trials, Scopus, and EMBASE, covering studies published up to February 2024. Randomised controlled trials (RCTs) and observational studies (n-RCTs) that reported the differences in the outcomes of AP for patients receiving LMWH in addition to the standard treatment (Intervention), compared to patients managed by standard treatment without LMWH (Control) were eligible. A random-effects model was used to calculate the pooled relative risk (RR) and mean differences (MD) with the corresponding 95% CI.

RESULTS

Thirteen studies were included in the meta-analysis, all published between 2004 and 2022. Eight studies were RCTs, and five were n-RCTs. Data from 13,709 patients (6.971 Interventions and 6.738 Controls) were analysed. The comparison of Intervention and Control groups showed the superiority of LMWH to standard treatments in terms of overall mortality (RR = 0.44, 95% CI = 0.31; 0.64, P < 0.0001, I2 = 51%), acute necrotic collections (RR = 0.24, 95% CI = 0.09; 0.62, P = 0.003, I2 = 0%), and organ failure (RR = 0.67, 95% CI = 0.48; 0.93, P = 0.02, I2 = 78%). The Intervention group showed superior outcomes compared with the Control group for gastrointestinal bleeding (RR = 0.64, 95% CI = 0.44; 0.94, P = 0.02, I2 = 0%), length of hospital stay (MD= - 6.08, 95% CI = - 10.08; - 2.07, P = 0.003, I2 = 98%), need for operative interventions (RR = 0.50, 95% CI = 0.29; 0.87, P = 0.01, I2 = 61%), and vascular thrombosis (RR = 0.43, 95% CI = 0.31; 0.61, P < 0.00001, I2 = 0%).

CONCLUSIONS

Moderate to high-quality evidence suggests that early intervention with LMWH could improve the prognosis of non-mild AP in terms of mortality, organ failure, and decreased incidence of vascular thrombosis. In light of our findings, integrating LMWH into the treatment regimen for moderate-severe to severe AP is advocated.

Venous Thrombosis in Acute Pancreatitis: What to and Not to Do?

Acute pancreatitis is an acute inflammatory condition of the pancreas that has not only local but systemic effects as well. Venous thrombosis is one such complication which can give rise to thrombosis of the peripheral vasculature in the form of deep vein thrombosis, pulmonary embolism, and splanchnic vein thrombosis. The prevalence of these complications increases with the severity of the disease and adds to the adverse outcomes profile. With better imaging and awareness, more cases are being detected, although many at times it can be an incidental finding. However, it remains understudied and strangely, most of the guidelines on the management of acute pancreatitis are silent on this aspect. This review offers an overview of the incidence, pathophysiology, symptomatology, diagnostic work-up, and management of venous thrombosis that develops in AP.

The Ongoing Debate on the Use of Prophylactic Antibiotics in Acute Pancreatitis-Is There a Conclusion? A Comprehensive Narrative Review

Acute pancreatitis (AP) is a common but often self-limiting disease in the majority of patients. However, in the minority, who may progress to moderately severe or severe AP, high mortality risk has been reported. Infected pancreatitis necrosis (IPN) in necrotising pancreatitis has been shown to result in more than twice the mortality rate compared with in sterile pancreatic necrosis. This raises the question on whether prophylactic antibiotics (PABs) should be given in subgroups of AP to prevent superimposed infection to improve survival outcomes. Despite numerous randomised controlled trials (RCTs), meta-analyses, and guidelines on the management of AP, there is a lack of strong evidence to suggest the use of PABs in AP. Additionally, use of PABs is associated with antimicrobial resistance. Considerable heterogeneity exists and limits the interpretation of results-subgroup of AP benefitting from PAB use, choice/class of PAB, and timing of administration from symptom onset and duration of PAB use. Only a minority of existing meta-analyses suggest mortality benefits and reduction in IPN. The majority of existing guidelines do not recommend the use of PABs in AP. More research is required to make more definitive conclusions. Currently, PAB should only be administered after multidisciplinary discussions led by pancreatology experts.

Splanchnic vein thrombosis in necrotizing pancreatitis: a post-hoc analysis of a nationwide prospective cohort

BACKGROUND

Treatment guidelines for splanchnic vein thrombosis in necrotizing pancreatitis are lacking due to insufficient data on the full clinical spectrum.

METHODS

We performed a post-hoc analysis of a nationwide prospective necrotizing pancreatitis cohort. Multivariable analyses were used to identify risk factors and compare the clinical course of patients with and without SVT.

RESULTS

SVT was detected in 97 of the 432 included patients (22%) (median onset: 4 days). Risk factors were left, central, or subtotal necrosis (OR 28.52; 95% CI 20.11-40.45), right or diffuse necrosis (OR 5.76; 95% CI 3.89-8.51), and younger age (OR 0.94; 95% CI 0.90-0.97). Patients with SVT had higher rates of bleeding (n = 10,11%) and bowel ischemia (n = 4,4%) compared to patients without SVT (n = 14,4% and n = 2,0.6%; OR 3.24; 95% CI 1.27-8.23 and OR 7.29; 95% CI 1.31-40.4, respectively), and were independently associated with ICU admission (adjusted OR 2.53; 95% CI 1.37-4.68). Spontaneous recanalization occurred in 62% of patients (n = 40/71). Radiological and clinical outcomes did not differ between patients treated with and without anticoagulants.

DISCUSSION

SVT is a common and early complication of necrotizing pancreatitis, associated with parenchymal necrosis and younger age. SVT is associated with increased complications and a worse clinical course, whereas anticoagulant use does not appear to affect outcomes.

Dynamic nomogram for predicting infected pancreatic necrosis in female patients of childbearing age with hypertriglyceridemia-induced acute pancreatitis

BACKGROUND

Hypertriglyceridemia is a common cause of acute pancreatitis. Pregnant women are at risk of developing hypertriglyceridemia-induced acute pancreatitis (HTG-AP); however, whether pregnancy increases the risk of infected pancreatic necrosis (IPN) is unknown.

AIM

We aimed to assess the association between pregnancy and IPN.

METHODS

This 10-year retrospective cohort study was conducted at Jinling Hospital. Adult female patients of childbearing age with HTG-AP between January 2013 and September 2022 were screened. Logistic regression analyses were performed to assess the risk factors for IPN. Patients admitted within 7 days were assigned to the training and validation sets to develop a dynamic nomogram for IPN prediction.

RESULTS

489 patients were included, and 144 developed IPN. Logistic regression analyses revealed pregnancy (OR: 2.578 95% CI: 1.474-4.510) as an independent risk factor for IPN. Gestation weeks, ARDS, albumin level, and serum creatinine level were selected as the predictors of the dynamic nomogram for IPN prediction, with good discrimination in the training set (AUC 0.867 95% CI: 0.794-0.940) and validation set (AUC 0.957 95% CI: 0.885-1.000).

CONCLUSION

Pregnancy increases the risk of IPN in adult patients of childbearing age with HTG-AP, and the dynamic nomogram may help risk stratification for IPN.

Epidemiology and risk factors for mortality in critically ill patients with pancreatic infection

Background

The AbSeS-classification defines specific phenotypes of patients with intra-abdominal infection based on the (1) setting of infection onset (community-acquired, early onset, or late-onset hospital-acquired), (2) presence or absence of either localized or diffuse peritonitis, and (3) severity of disease expression (infection, sepsis, or septic shock). This classification system demonstrated reliable risk stratification in intensive care unit (ICU) patients with intra-abdominal infection. This study aimed to describe the epidemiology of ICU patients with pancreatic infection and assess the relationship between the components of the AbSeS-classification and mortality.

Methods

This was a secondary analysis of an international observational study ("AbSeS") investigating ICU patients with intra-abdominal infection. Only patients with pancreatic infection were included in this analysis (n=165). Mortality was defined as ICU mortality within 28 days of observation for patients discharged earlier from the ICU. Relationships with mortality were assessed using logistic regression analysis and reported as odds ratio (OR) and 95% confidence interval (CI).

Results

The overall mortality was 35.2% (n=58). The independent risk factors for mortality included older age (OR=1.03, 95% CI: 1.0 to 1.1 P=0.023), localized peritonitis (OR=4.4, 95% CI: 1.4 to 13.9 P=0.011), and persistent signs of inflammation at day 7 (OR=9.5, 95% CI: 3.8 to 23.9, P<0.001) or after the implementation of additional source control interventions within the first week (OR=4.0, 95% CI: 1.3 to 12.2, P=0.013). Gram-negative bacteria were most frequently isolated (n=58, 49.2%) without clinically relevant differences in microbial etiology between survivors and non-survivors.

Conclusions

In pancreatic infection, a challenging source/damage control and ongoing pancreatic inflammation appear to be the strongest contributors to an unfavorable short-term outcome. In this limited series, essentials of the AbSeS-classification, such as the setting of infection onset, diffuse peritonitis, and severity of disease expression, were not associated with an increased mortality risk.ClinicalTrials.gov number: NCT03270345.

A narrative review of acute pancreatitis-induced splanchnic vein thrombosis: from pathogenesis to clinical management

Acute pancreatitis-induced splanchnic vein thrombosis (APISVT) is an important sequela complication of acute pancreatitis, which may cause poor prognosis, such as severe gastrointestinal hemorrhage, bowel ischemic necrosis and liver failure. However, its mechanism remains uncertain, and there is not a general consensus on the management. In this study, we reviewed the latest academic publications in APISVT, and discussed its pathogenesis, clinical presentation, adverse outcome and treatment, especially focused on the role of anticoagulant therapy. It was indicated that anticoagulation therapy can significantly elevate thrombus recanalization and reduce the incidence of complications and mortality with no increase of bleeding. Actually, as most of these studies were retrospective analyses and prospective studies included small samples, the conclusion remains controversial. Thus, well-designed randomized controlled trials are urged to verify the effectiveness and safety of anticoagulation therapy for APISVT.

Prognostic significance of organ failure and infected pancreatic necrosis in acute pancreatitis: An updated systematic review and meta-analysis

OBJECTIVES

In patients with acute pancreatitis (AP), minimally invasive treatment and the step-up approach have been widely used to deal with infected pancreatic necrosis (IPN) in the last decade. It is unclear whether IPN has become a less important determinant of mortality relative to organ failure (OF). We aimed to statistically aggregate recent evidence from published studies to determine the relative importance of IPN and OF as determinants of mortality in patients with AP (PROSPERO: CRD42020176989).

METHODS

Relevant studies were sourced from MEDLINE and EMBASE databases. Relative risk (RR) or weighted mean difference (WMD) was analyzed as outcomes. A two-sided P value of less than 0.05 was regarded as statistical significance.

RESULTS

Forty-three studies comprising 11 601 patients with AP were included. The mortality was 28% for OF patients and 24% for those with IPN. Patients with OF without IPN had a significantly higher risk of mortality compared to those with IPN but without OF (RR 3.72, P < 0.0001). However, patients with both OF and IPN faced the highest risk of mortality. Additionally, IPN increased length of stay in hospital for OF patients (WMD 28.75, P = 0.032).

CONCLUSION

Though IPN remains a significant concern, which leads to increased morbidity and longer hospital stay, it is a less critical mortality determinant compared to OF in AP.

Microenvironment of pancreatic inflammation: calling for nanotechnology for diagnosis and treatment

Acute pancreatitis (AP) is a common and life-threatening digestive disorder. However, its diagnosis and treatment are still impeded by our limited understanding of its etiology, pathogenesis, and clinical manifestations, as well as by the available detection methods. Fortunately, the progress of microenvironment-targeted nanoplatforms has shown their remarkable potential to change the status quo. The pancreatic inflammatory microenvironment is typically characterized by low pH, abundant reactive oxygen species (ROS) and enzymes, overproduction of inflammatory cells, and hypoxia, which exacerbate the pathological development of AP but also provide potential targeting sites for nanoagents to achieve early diagnosis and treatment. This review elaborates the various potential targets of the inflammatory microenvironment of AP and summarizes in detail the prospects for the development and application of functional nanomaterials for specific targets. Additionally, it presents the challenges and future trends to develop multifunctional targeted nanomaterials for the early diagnosis and effective treatment of AP, providing a valuable reference for future research.

Therapeutic anticoagulation for splanchnic vein thrombosis in acute pancreatitis: A national survey and case-vignette study

BACKGROUND

Splanchnic vein thrombosis (SVT) is a major complication of moderate and severe acute pancreatitis. There is no consensus on whether therapeutic anticoagulation should be started in patients with acute pancreatitis and SVT.

AIM

To gain insight into current opinions and clinical decision making of pancreatologists regarding SVT in acute pancreatitis.

METHODS

A total of 139 pancreatologists of the Dutch Pancreatitis Study Group and Dutch Pancreatic Cancer Group were approached to complete an online survey and case vignette survey. The threshold to assume group agreement was set at 75%.

RESULTS

The response rate was 67% (n = 93). Seventy-one pancreatologists (77%) regularly prescribed therapeutic anticoagulation in case of SVT, and 12 pancreatologists (13%) for narrowing of splanchnic vein lumen. The most common reason to treat SVT was to avoid complications (87%). Acute thrombosis was the most important factor to prescribe therapeutic anticoagulation (90%). Portal vein thrombosis was chosen as the most preferred location to initiate therapeutic anticoagulation (76%) and splenic vein thrombosis as the least preferred location (86%). The preferred initial agent was low molecular weight heparin (LMWH; 87%). In the case vignettes, therapeutic anticoagulation was prescribed for acute portal vein thrombosis, with or without suspected infected necrosis (82% and 90%), and thrombus progression (88%). Agreement was lacking regarding the selection and duration of long-term anticoagulation, the indication for thrombophilia testing and upper endoscopy, and about whether risk of bleeding is a major barrier for therapeutic anticoagulation.

CONCLUSION

In this national survey, the pancreatologists seemed to agree on the use of therapeutic anticoagulation, using LMWH in the acute phase, for acute portal thrombosis and in the case of thrombus progression, irrespective of the presence of infected necrosis.

Timing of minimally invasive step-up intervention for symptomatic pancreatic necrotic fluid collections: A systematic review and meta-analysis

BACKGROUND AND AIMS

Minimally invasive step-up interventions are now the standard treatment recommended by current guidelines for symptomatic pancreatic necrotic fluid collections (PNFC); however, it is controversial whether delayed treatment after four weeks should always be used in patients who have failed conservative treatment and whose condition has not improved or worsened. The aim of this meta-analysis was to evaluate the impacts of the different timing of interventions on the clinical outcomes and prognosis of patients with symptomatic PNEC requiring intervention.

METHODS

We searched Embase, Cochrane Library, PubMed and Web of Science databases to identify comparative studies assessing the safety and efficacy of early and postponed interventions in treating symptomatic PNFC.

PRIMARY OUTCOME

Mortality. Secondary outcomes included some major complications, need for further minimally invasive necrosectomy and length of hospital stay.

RESULTS

This meta-analysis included ten studies (2 RCTs and 8 observational studies) with a total of 1178 symptomatic PNFC patients who required intervention. Pooled results showed that there was no significant difference between early minimally invasive intervention and postponed intervention in mortality(OR 1.41, 95%CI 0.93-2.12;p = 0.10) and the incidence of early and late complications, but the early intervention group had a significantly increased need for further minimally invasive necrosectomy compared with postponed intervention (OR 2.04,95%CI 1.04-4.03; p = 0.04). There was no increase in length of stay for patients who received early intervention compared to postponed drainage (MD 3.53, 95% CI -4.20, 11.27; p = 0.37).

CONCLUSION

Intervention before four weeks should be considered for patients with PNFC complicated by persistent organ failure or infections, who have been treated conservatively to the maximum extent possible.

Anticoagulation Therapy for Splanchnic Vein Thrombosis Associated With Acute Pancreatitis: A Systematic Review and Meta-Analysis

Splanchnic vein thrombosis (SVT) is not rare in patients with acute pancreatitis. It remains unclear about whether anticoagulation should be given for acute pancreatitis-associated SVT. The PubMed, EMBASE, and Cochrane Library databases were searched. Rates of SVT recanalization, any bleeding, death, intestinal ischemia, portal cavernoma, and gastroesophageal varices were pooled and compared between patients with acute pancreatitis-associated SVT who received and did not receive therapeutic anticoagulation. Pooled rates and risk ratios (RRs) with 95% confidence intervals (CIs) were calculated. Heterogeneity among studies was evaluated. Overall, 16 studies including 698 patients with acute pancreatitis-associated SVT were eligible. After therapeutic anticoagulation, the pooled rates of SVT recanalization, any bleeding, death, intestinal ischemia, portal cavernoma, and gastroesophageal varices were 44.3% (95%CI = 32.3%-56.6%), 10.7% (95%CI = 4.9%-18.5%), 13.3% (95%CI = 6.9%-21.4%), 16.8% (95%CI = 6.9%-29.9%), 21.2% (95%CI = 7.5%-39.5%), and 29.1% (95%CI = 16.1%-44.1%), respectively. Anticoagulation therapy significantly increased the rate of SVT recanalization (RR = 1.69; 95%CI = 1.29-2.19; P < .01), and marginally increased the risk of bleeding (RR = 1.98; 95%CI = 0.93-4.22; P = .07). The rates of death (RR = 1.42; 95%CI = 0.62-3.25; P = .40), intestinal ischemia (RR = 2.55; 95%CI = 0.23-28.16; P = .45), portal cavernoma (RR = 0.51; 95%CI = 0.21-1.22; P = .13), and gastroesophageal varices (RR = 0.71; 95%CI = 0.38-1.32; P = .28) were not significantly different between patients who received and did not receive anticoagulation therapy. Heterogeneity was statistically significant in the meta-analysis of intestinal ischemia, but not in those of SVT recanalization, any bleeding, death, portal cavernoma, or gastroesophageal varices. Anticoagulation may be effective for recanalization of acute pancreatitis-associated SVT, but cannot improve the survival. Randomized controlled trials are warranted to further investigate the clinical significance of anticoagulation therapy in such patients.

Guidelines for the management of patients with severe acute pancreatitis, 2021

OBJECTIVE

To provide guidelines for the management of the intensive care patient with severe acute pancreatitis.

DESIGN

A consensus committee of 22 experts was convened. A formal conflict-of-interest (COI) policy was developed at the beginning of the process and enforced throughout. The entire guideline construction process was conducted independently of any industrial funding (i.e. pharmaceutical, medical devices). The authors were required to follow the rules of the Grading of Recommendations Assessment, Development and Evaluation (GRADE®) system to guide assessment of quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasised.

METHODS

The most recent SFAR and SNFGE guidelines on the management of the patient with severe pancreatitis were published in 2001. The literature now is sufficient for an update. The committee studied 14 questions within 3 fields. Each question was formulated in a PICO (Patients Intervention Comparison Outcome) format and the relevant evidence profiles were produced. The literature review and recommendations were made according to the GRADE® methodology.

RESULTS

The experts' synthesis work and their application of the GRADE® method resulted in 24 recommendations. Among the formalised recommendations, 8 have high levels of evidence (GRADE 1+/-) and 12 have moderate levels of evidence (GRADE 2+/-). For 4 recommendations, the GRADE method could not be applied, resulting in expert opinions. Four questions did not find any response in the literature. After one round of scoring, strong agreement was reached for all the recommendations.

CONCLUSIONS

There was strong agreement among experts for 24 recommendations to improve practices for the management of intensive care patients with severe acute pancreatitis.

Prognostic factors associated with development of infected necrosis in patients with acute necrotizing or severe pancreatitis-A systematic review and meta-analysis

PURPOSE

Acute pancreatitis is a potentially life-threatening condition with a wide spectrum of clinical presentation and illness severity. An infection of pancreatic necrosis (IPN) results in a more than twofold increase in mortality risk as compared with patients with sterile necrosis. We sought to identify prognostic factors for the development of IPN among adult patients with severe or necrotizing pancreatitis.

METHODS

We conducted this prognostic review in accordance with systematic review methodology guidelines. We searched six databases from inception through March 21, 2021. We included English language studies describing prognostic factors associated with the development of IPN. We pooled unadjusted odds ratio (uOR) and adjusted odds ratios (aOR) for prognostic factors using a random-effects model. We assessed risk of bias using the Quality in Prognosis Studies tool and certainty of evidence using the GRADE approach.

RESULTS

We included 31 observational studies involving 5,210 patients. Factors with moderate or higher certainty of association with increased IPN risk include older age (uOR, 2.19; 95% confidence interval [CI], 1.39-3.45, moderate certainty), gallstone etiology (aOR, 2.35; 95% CI, 1.36-4.04, high certainty), greater than 50% necrosis of the pancreas (aOR, 3.61; 95% CI, 2.15-6.04, high certainty), delayed enteral nutrition (aOR, 2.09; 95% CI, 1.26-3.47, moderate certainty), multiple or persistent organ failure (aOR, 11.71; 95% CI, 4.97-27.56, high certainty), and invasive mechanical ventilation (uOR, 12.24; 95% CI, 2.28-65.67, high certainty).

CONCLUSION

This meta-analysis confirms the association between several clinical early prognostic factors and the risk of IPN development among patients with severe or necrotizing pancreatitis. These findings provide the foundation for the development of an IPN risk stratification tool to guide more targeted clinical trials for prevention or early intervention strategies.

LEVEL OF EVIDENCE

Systematic review and meta-analysis, Level IV.

Splanchnic Vein Thrombosis: A Harbinger of Infection in Peri/Pancreatic Necrotic Collections

OBJECTIVE

Infected pancreatic necrosis (IPN) is associated with poor outcomes. The present study looked at incidence of infection and predictors, if any, in these collections.

METHODS

This prospective observational study was done between July 2019 and October 2020. Symptomatic patients of acute necrotic collections and walled-off necrosis of pancreas requiring drainage were included. Necrotic fluid and blood were analyzed for growth of organisms.

RESULTS

Sixty-two patients were included. The mean age was 36.8 years (standard deviation, 11.5 years). Male-female ratio was 4:1. Alcohol was the most common etiology. Infection was noted in 44 of the 62 patients (70.9%) and bacteremia noted in 23 of the 62 patients (37%). Escherichia coli was the most common organism in necrotic collections and Staphylococcus was the most common organism isolated from blood culture. The patients with Modified Computed Tomography-Severity Index of 8 of higher ( P < 0.001) had significant association with IPN but not with bacteremia. However, splanchnic vein thrombosis ( P = 0.022) was significantly associated with development of IPN as well as bacteremia on both univariate and multivariate analysis.

CONCLUSIONS

Escherichia coli and Staphylococcus were the most common organisms grown from necrotic collections and blood respectively. Presence of splanchnic vein thrombosis was a significant factor for development of IPN and bacteremia on univariate as well as multivariate analysis.

Therapeutic anticoagulation for splanchnic vein thrombosis in acute pancreatitis: A systematic review and meta-analysis

OBJECTIVES

The optimal management of patients with acute pancreatitis (AP) and splanchnic vein thrombosis (SVT) remains unknown. This systematic review and meta-analysis aimed to see if therapeutic anticoagulation (AC) improves outcomes in patients with AP and SVT.

METHODS

A systematic review was performed according to PRISMA guidelines. Main outcomes were recanalization, recurrent venous thromboembolism, development of varices, collaterals or cavernoma, haemorrhage and mortality. Meta-analysis were performed with the Mantel-Haenszel random effect models.

RESULTS

Seven retrospective cohort studies (3495 patients) were included. SVT occurred in 233 (7%) patients and involved most frequently the splenic vein (44%). Therapeutic AC was administered to 109 (47%) patients, most frequently to those with triple vessel thrombosis (72%) and least to those with isolated splenic vein (22%) or superior mesenteric vein thrombosis (0%). Most studies administered (low molecular weight) heparin followed by warfarin (duration ranged between 1.5 and 12 months). This meta-analysis showed an absolute risk difference of 9% (95% confidence interval [CI] = -11-28%) for recanalization, -3% (95% CI = -19-12%) for the development of varices, collaterals or cavernoma, 3% (95% CI = -6-12%) for haemorrhage and 2% (95% CI = -8-12%) for mortality.

CONCLUSIONS

Based on the currently available data, it remains unclear if therapeutic anticoagulation provides benefit to acute pancreatitis patients with splanchnic vein thrombosis. These results are based on low quality data underlining the need for further higher quality studies.

Incidence and treatment of splanchnic vein thrombosis in patients with acute pancreatitis: A systematic review and meta-analysis

BACKGROUND AND AIM

This meta-analysis aimed to estimate the incidence of splanchnic vein thrombosis (SVT) in patients with acute pancreatitis and assess the effects of therapeutic anticoagulation.

METHODS

Systematic searches of the Medline, Embase, and Cochrane databases were undertaken to identify studies reporting the incidence and outcomes associated with SVT in patients with acute pancreatitis. The pooled incidence, odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using a random effects model. PROSPERO database registration no. CRD 42021230912.

RESULTS

Only 18 of the 238 studies identified met the inclusion criteria. Of the 943 patients who had SVT, 264 (28.0%) received anticoagulation. The pooled incidence of SVT at first presentation of acute pancreatitis was 15% (95% CI 5 to 26%), but was 17% (95% CI 14 to 20%) in all studies. Recanalization was more likely to occur in the anticoagulation-treated than in the untreated group (OR 0.51, 95% CI 0.31 to 0.83, P = 0.007). There were no differences in hemorrhagic complications (OR 2.27, 95% CI 0.81 to 6.37, P = 0.12) or overall mortality (OR 2.37, 95% CI 0.86 to 6.52, P = 0.10) in relation to the use of anticoagulation. The overall incidence of portal hypertension in patients was 60% (95% CI 55 to 65%). However, it was not possible to determine the incidence in each group.

CONCLUSIONS

The incidence of SVT in patients with acute pancreatitis is significant. Treatment with anticoagulants improved the odds of recanalization but did not increase the risk of hemorrhagic complications or overall mortality.

Influence of extracorporeal cytokine adsorption on hemodynamics in severe acute pancreatitis: Results of the matched cohort pancreatitis cytosorbents inflammatory cytokine removal (PACIFIC) study

BACKGROUND

Outcome of severe acute pancreatitis (SAP) highly depends on the degree of systemic inflammation and organ failure. Although treatment approaches targeting the inflammatory cascade have failed in pancreatitis, recent studies suggest that extracorporeal cytokine adsorption effectively reduces concentrations of pro-inflammatory cytokines and potentially improves the outcome of sepsis.

METHODS

Sixteen patients with SAP, presenting within 7 days upon onset of pain, an APACHE-II score of ≥10 and ≥1 marker of poor prognosis, received 2 consecutive 24-h treatments with CytoSorb® extracorporeal cytokine adsorption (intervention group). Hemodynamics, organ failure, and mortality were compared with an APACHE-II score-matched retrospective control group of 32 patients.

RESULTS

The primary objective (20% decrease in the vasopressor dependency index or 20% increase in the cardiac index) was reached in 68.8% of the intervention and 28.1% of the control patients (p = 0.007), respectively. The cytokine adsorption significantly reduced IL-6 (-1998 pg/ml, p = 0.005) serum levels and resulted in stable CRP (p = 0.101) and decreased PCT (p = 0.003) levels in contrast to increased CRP (p = 0.014) and stable PCT levels (p = 0.695) in the control group. While mortality and improvement of respiratory failure were similar in both groups, renal failure significantly improved (change of KDIGO classification 72 h postcytokine adsorption [-1 vs. 0, p = 0.005]) and the SOFA score significantly decreased (day 5: -1.8 ± 2.0 vs. 1 ± 3.8, p = 0.013) in the intervention group.

CONCLUSION

Cytokine adsorption might be an effective treatment option to stabilize hemodynamics in SAP. It decreases levels of the pro-inflammatory marker IL-6 and stabilizes organ function according to serial SOFA score assessments.

Use of therapeutic anticoagulation in splanchnic vein thrombosis associated with acute pancreatitis: a systematic review and meta-analysis

Background

Splanchnic vein thrombosis is a well-recognized local vascular complication of acute pancreatitis (AP), estimated to occur in approximately 15% of patients. While splanchnic vein recanalization occurs spontaneously in approximately one third of patients, severe complications such as bowel ischemia and liver failure have also been reported. At present, there is no consensus on whether patients presenting with AP-associated splanchnic vein thrombosis should receive therapeutic anticoagulation.

Methods

We searched multiple databases from inception through December 2020 to collect studies that compared the clinical outcomes of patients with AP and splanchnic vein thrombosis who received therapeutic anticoagulation (AC group) with those who did not (N-AC group). A meta-analysis was performed to calculate the relative risk (RR) of vessel recanalization, bleeding complications, collateral formation and death in the 2 groups.

Results

Seven studies with 8353 patients, 339 of whom had splanchnic vein thrombosis, were included in the final analysis. A total of 154 patients (45.4%) had acute severe pancreatitis. A significantly higher proportion of patients had vessel recanalization in the AC group: RR 1.6, 95% confidence interval 1.17-2.27; I²=0%; P=0.004. There was no difference between the 2 groups in the RR of bleeding complications, collateral formation and death.

Conclusions

Our analysis demonstrated that, among patients with AP-associated splanchnic vein thrombosis, therapeutic anticoagulation resulted in recanalization of the involved vessels without significantly increasing the risk of bleeding complications. There was no difference in the RR of death or the rates of collateral vessel formation during the follow up.

Extrapancreatic infections are common in acute pancreatitis and they are related to organ failure: a population-based study

BACKGROUND

Although the impact of pancreatic infections in acute pancreatitis has been studied extensively, there are no population-based data on extrapancreatic infections and their potential relation to organ failure. We aimed to study the occurrence of pancreatic and extrapancreatic bacterial infections in acute pancreatitis and their relation to patient outcome.

PATIENTS AND METHODS

All patients with first-time acute pancreatitis from 2003 to 2012 in a defined area in Sweden were retrospectively evaluated. Data on acute pancreatitis severity, organ failure, infections, and in-hospital mortality were collected.

RESULTS

Overall, 304 bacterial infections occurred in 248/1457 patients (17%). Fifteen percent had extrapancreatic and 2% had pancreatic infections. The lungs (35%), the urinary tract (24%), and the bile ducts (18%) were the most common sites of extrapancreatic infections. Organ failure, severe acute pancreatitis, and in-hospital mortality were more common in patients with vs those without (pancreatic/extrapancreatic) infections (P < 0.05). Organ failure and severe acute pancreatitis occurred more frequently in pancreatic vs extrapancreatic infections (70% vs 34%, P < 0.001 and 67% vs 28%, P < 0.001), but in-hospital mortality did not differ between the two groups (7.4% vs 6.8%, P = 1.0). Both pancreatic and extrapancreatic infections were independent predictors of organ failure (P < 0.05). Out of culture-positive infections, 18% were due to antibiotic-resistant bacteria, without any significant difference between extrapancreatic vs pancreatic infections (P > 0.05). About two out of five infections were of nosocomial origin.

CONCLUSION

Extrapancreatic infections occurred in 15% and pancreatic infections in 2% of patients with first-time acute pancreatitis. Both pancreatic and extrapancreatic infections were independent predictors of organ failure, leading to increased mortality.

Impact of prior antibiotics on infected pancreatic necrosis microbiology in ICU patients: a retrospective cohort study

Background

Recent guidelines advise against prophylactic antibiotics in patients with necrotizing pancreatitis, advocating instead a step-up drainage and necrosectomy strategy with antibiotics as dictated by microbiological findings. However, prompt antibiotic therapy is recommended in patients with sepsis or septic shock, a possible presentation of infected pancreatic necrosis (IPN). Consequently, in many critically ill patients with IPN, pancreatic samples are collected only after broad-spectrum antibiotic therapy initiation. Whether this prior antibiotic exposure alters the microbiological findings is unknown. The main objective was to determine whether prior antibiotic exposure sterilized the samples collected during procedures for suspected IPN in patients admitted to the intensive care unit (ICU) for acute pancreatitis with suspected IPN. We retrospectively studied 56 consecutive ICU patients admitted with suspected IPN. We collected details on the microbiological samples and antimicrobials used. A definite diagnosis of IPN was given when bacteria were identified in pancreatic samples.

Results

In all, 137 pancreatic samples were collected, including 91 (66.4%) after antibiotic therapy initiation. IPN was confirmed in 48 (86%) patients. The proportion of positive samples was 74 (81.3%) in antibiotic-exposed patients and 32/46 (69.5%) in unexposed patients (p = 0.58). Of the 74 positive samples from exposed patients, 62 (84%) had organisms susceptible to the antibiotics used. One-third of samples contained more than one organism. Among patients with IPN, 37.5% had positive blood cultures. Multidrug- or extensively drug-resistant bacteria were identified at some point in half the patients. Enterobacter cloacae complex was more frequent in the exposed group (p = 0.02), as were Gram-negative anaerobic bacteria (p = 0.03).

Conclusion

Antibiotic exposure before sampling did not seem to affect culture positivity of pancreatic samples to confirm IPN, but may affect microbiological findings. Our results suggest that, in patients with sepsis and suspected IPN, antibiotics should be started immediately and pancreatic samples obtained as soon as possible thereafter. In other situations, antibiotics can be withheld until the microbiological results of pancreatic samples are available, to ensure accurate targeting of the spectrum to bacterial susceptibility patterns.

ClinicalTrials.gov number NCT03253861

Current practice of anticoagulant in the treatment of splanchnic vein thrombosis secondary to acute pancreatitis

BACKGROUND

Severe acute pancreatitis is a common diagnosis in emergency general surgery and can be a cause of significant morbidity and mortality. A consequence of severe acute pancreatitis is thrombus in the splanchnic veins. These thrombi can potentially lead to bowel ischemia or hepatic failure. However, another complication of severe acute pancreatitis is retroperitoneal bleeding. At this time, it is unclear if treating patients for splanchnic vein thrombosis in the context of severe acute pancreatitis is associated with any outcome benefit. A systematic review might clarify this question.

DATA SOURCES

A two-fold search strategy (one broad and one precise) looked at all published literature. The review was registered on PROSPERO (ID: CRD42018102705). MEDLINE, EMBASE, PubMed, Cochrane and Web of Science databases were searched and potentially relevant papers were reviewed independently by two researchers. Any disagreement was reviewed by a third independent researcher. Primary outcome was reestablishment of flow in the thrombosed vein versus bleeding complications.

RESULTS

Of 1462 papers assessed, a total of 16 papers were eligible for inclusion. There were no randomized controlled trials, 2 were case series, 5 retrospective single-center studies and 9 case reports. There were a total of 198 patients in these studies of whom 92 (46.5%) received anticoagulation therapy. The rates of recanalization of veins in the treated and non-treated groups was 14% and 11% and bleeding complications were 16% and 5%, respectively. However, the included studies were too heterogeneous to undertake a meta-analysis.

CONCLUSIONS

The systematic review highlights the lack evidence addressing this clinical question. Therefore a randomized controlled trial would be appropriate to undertake.

How to deal with severe acute pancreatitis in the critically ill

PURPOSE OF REVIEW

To review recent literature on the management of patients with severe acute pancreatitis (SAP) admitted to an ICU.

RECENT FINDINGS

SAP is a devastating disease associated with a high morbidity and mortality. Recent evidence advocates adequate risk assessment and severity prediction (including intra-abdominal pressure monitoring), tailored fluid administration favoring balanced crystalloids, withholding prophylactic antibiotic therapy, and early detection and treatment of extra-pancreatic and fungal infections. Urgent (within 24-48 h after diagnosis) endoscopic retrograde cholangiopancreatography is indicated when persistent biliary obstruction or cholangitis are present. Corticosteroid therapy (mainly dexamethasone) can reduce the need for surgical interventions, length of hospital stay, and mortality. Peritoneal lavage may significantly lower morbidity and mortality. Hemofiltration may offer substantial benefit but more studies are needed to prove its efficacy. Enteral feeding using a polymeric formula and provided early through a nasogastric tube is recommended but has no survival benefit compared with parenteral nutrition. Probiotics could be beneficial, however no clear recommendations can be made.

SUMMARY

Management of SAP is multimodal with emphasis on monitoring, adequate fluid resuscitation, avoiding prophylactic use of antibiotics, cause-directed procedures or treatment, and organ support. There is a role for early enteral nutrition including probiotics.

Antibacterial and Antifungal Therapy for Patients with Acute Pancreatitis at High Risk of Pancreatogenic Sepsis (Review)

Controlling infection is crucial in treating patients with acute pancreatitis (AP). The infectious process in AP often predisposes to subsequent sepsis by damaging not only the pancreas, but retroperitoneal tissues as well. Among other AP-associated factors, are the rapidly developing immune imbalance, the poor penetration of antimicrobial agents into necrotic tissue, and the impossibility of a single surgical debridement. Antibacterial and antifungal therapy for patients with infected necrosis and AP-associated extra-pancreatic infections remains a complex and largely unresolved problem, partially due to the high occurrence of multiresistant pathogens. The preventive use of antimicrobial agents has been discussed in the literature; however, the lack of consistent results makes it difficult to develop a unified strategy and clinical guidelines on this specific issue. Recent meta-analyses provide no conclusive evidence that antibacterial prophylaxis reduces the infection rate, mortality, or the need for surgical treatment in patients with necrotizing pancreatitis. We found only two studies indicating the benefits of using carbapenems for prophylactic purposes and one meta-analysis indicating a reduction in mortality under antibiotic treatment started no later than 72 h after the onset of the attack. Selective bowel decontamination is considered as one of the preventive anti-infection measures, although the available data may not be fully reliable. The main indications for antibacterial therapy in patients with AP are confirmed infected necrosis or extra-pancreatic infection, as well as clinical symptoms of suspected infection. Intra-arterial administration or local treatment with antibiotics can increase the efficacy of antibacterial therapy. No randomized studies on antifungal prophylaxis in AP are available; some reports though recommend using such therapy among patients at high risk of invasive candidiasis.

Organ Failure Due to Systemic Injury in Acute Pancreatitis

Acute pancreatitis may be associated with both local and systemic complications. Systemic injury manifests in the form of organ failure, which is seen in approximately 20% of all cases of acute pancreatitis and defines "severe acute pancreatitis." Organ failure typically develops early in the course of acute pancreatitis, but also may develop later due to infected pancreatic necrosis-induced sepsis. Organ failure is the most important determinant of outcome in acute pancreatitis. We review here the current understanding of the risk factors, pathophysiology, timing, impact on outcome, and therapy of organ failure in acute pancreatitis. As we discuss the pathophysiology of severe systemic injury, the distinctions between markers and mediators of severity are highlighted based on evidence supporting their causality in organ failure. Emphasis is placed on clinically relevant end points of organ failure and the mechanisms underlying the pathophysiological perturbations, which offer insight into potential therapeutic targets to treat.