Effects of a multimodal management strategy for acute mesenteric ischemia on survival and intestinal failure

Portal vein thrombosis: diagnosis, management, and endpoints for future clinical studies

Portal vein thrombosis (PVT) refers to the development of a non-malignant obstruction of the portal vein, its branches, its radicles, or a combination. This Review first provides a comprehensive overview of all aspects of PVT, namely the specifics of the portal venous system, the risk factors for PVT, the pathophysiology of portal hypertension in PVT, the interest in non-invasive tests, as well as therapeutic approaches including the effect of treating risk factors for PVT or cause of cirrhosis, anticoagulation, portal vein recanalisation by interventional radiology, and prevention and management of variceal bleeding in patients with PVT. Specific issues are also addressed including portal cholangiopathy, mesenteric ischaemia and intestinal necrosis, quality of life, fertility, contraception and pregnancy, and PVT in children. This Review will then present endpoints for future clinical studies in PVT, both in patients with and without cirrhosis, agreed by a large panel of experts through a Delphi consensus process. These endpoints include classification of portal vein thrombus extension, classification of PVT evolution, timing of assessment of PVT, and global endpoints for studies on PVT including clinical outcomes. These endpoints will help homogenise studies on PVT and thus facilitate reporting, comparison between studies, and validation of future studies and trials on PVT.

Management of Short Bowel Syndrome With Chronic Intestinal Failure: A Single-Center Experience in Portugal

INTRODUCTION

Short bowel syndrome with chronic intestinal failure (SBS/CIF) is the inability to maintain protein-energy, fluid, electrolyte, or micronutrient balance due to a short bowel. Although SBS/CIF is rare, its clinical management is complex, challenging, expensive, and time-consuming.

AIM

This study aimed to analyze a single center's experience with SBS/CIF in adult patients treated with home parenteral nutrition (HPN).

MATERIALS AND METHODS

A retrospective single-center analysis of all 13 consecutive adult patients with SBS/CIF was included in an HPN program between January 1994 and August 2023.

RESULTS

Between 1992 and 2023, 13 patients were included in an HPN program. The primary underlying pathology was acute mesenteric ischemia. The median age of starting HPN was 44 years. Most were subjected to several surgeries of extensive intestinal resection with posterior intestinal reconstruction. Five of the 13 patients died while on HPN with a median duration of 42 months. The causes of death related to HPN were catheter sepsis, endocarditis with cardiac failure, or hepatic failure. One patient died due to underlying pathology: pelvic abscesses and bleeding related to radiotherapy. Eight patients remain alive, with a median time of HPN of 173 months. During the HPN support, the most frequent complications were venous catheter infection and venous territory thrombosis. None of the eight patients alive have hepatic failure. Two patients recently started teduglutide with good tolerance and need a reduction in HPN support. All eight patients have a satisfactory quality of life (parenteral support needs range between five and two nutrition bags per week).  Conclusion: Home parenteral nutrition remains the gold standard of SBS/CIF treatment, although teduglutide may reduce HPN needs and complications and provide a better quality of life. Despite the small number of patients, the results shown in this study are not inferior to those in large-volume centers. The existence of the commitment and interest of professionals involved in SBS/CIF at Centro Hospitalar Universitário de Santo António, Portugal, was a fundamental key to achieving those results. A multidisciplinary healthcare group for HPN support can be essential to ensuring these patients' survival and quality of life.

Predictors of Survival Without Intestinal Resection after First-Line Endovascular Revascularization in Patients with Acute Arterial Mesenteric Ischemia

Background Acute arterial mesenteric ischemia requires emergency treatment and is associated with high mortality rate and poor quality of life. Identifying factors associated with survival without intestinal resection (hereafter, intestinal resection-free [IRF] survival) could help in treatment decision-making after first-line endovascular revascularization. Purpose To identify factors associated with 30-day IRF survival in patients with acute arterial mesenteric ischemia whose first-line treatment was endovascular revascularization. Materials and Methods Patients with acute arterial mesenteric ischemia whose first-line treatment was endovascular revascularization because of a low probability of bowel necrosis were included in this single-center retrospective cohort (May 2014 to August 2022). Patient demographics, laboratory values, clinical characteristics at admission, CT scans, angiograms, and endovascular revascularization-related variables were included. The primary end point was 30-day IRF survival, and secondary end points were 3-month, 1-year, and 3-year overall survival. Factors independently associated with 30-day IRF survival were identified with binary logistic regression. Results A total of 117 patients (median age, 70 years [IQR, 60-77]; 53 female, 64 male) were included. Within 30 days after revascularization, 73 of 117 patients (62%) survived without resection, 28 of 117 (24%) survived after resection, 14 of 117 (12%) died without resection, and two of 117 (2%) underwent resection but died. The 30-day IRF survival was 63% (74 of 117). The 3-month, 1-year, and 3-year mortality rate was 18% (21 of 117), 21% (25 of 117), and 27% (32 of 117), respectively. Independent predictors of 30-day IRF survival were persistent bowel enhancement at initial CT (odds ratio [OR], 0.3; 95% CI: 0.2, 0.8; P = .013) and C-reactive protein (CRP) level less than 100 mg/L (OR, 0.3; 95% CI: 0.1, 0.8; P = .002). The 30-day IRF survival was 86%, 61%, 47%, and 23% in patients with both favorable features, persistent bowel enhancement but CRP level greater than 100 mg/L, no bowel enhancement but CRP level less than 100 mg/L, and both unfavorable features, respectively. Conclusion Independent predictors associated with 30-day IRF survival in patients with acute arterial mesenteric ischemia whose first-line treatment was endovascular revascularization were persistent bowel wall enhancement at initial CT and CRP level less than 100 mg/L. © RSNA, 2024 Supplemental material is available for this article.

Deep learning algorithm applied to plain CT images to identify superior mesenteric artery abnormalities

OBJECTIVES

Atypical presentations, lack of biomarkers, and low sensitivity of plain CT can delay the diagnosis of superior mesenteric artery (SMA) abnormalities, resulting in poor clinical outcomes. Our study aims to develop a deep learning (DL) model for detecting SMA abnormalities in plain CT and evaluate its performance in comparison with a clinical model and radiologist assessment.

MATERIALS AND METHODS

A total of 1048 patients comprised the internal (474 patients with SMA abnormalities, 474 controls) and external testing (50 patients with SMA abnormalities, 50 controls) cohorts. The internal cohort was divided into the training cohort (n = 776), validation cohort (n = 86), and internal testing cohort (n = 86). A total of 5 You Only Look Once version 8 (YOLOv8)-based DL submodels were developed, and the performance of the optimal submodel was compared with that of a clinical model and of experienced radiologists.

RESULTS

Of the submodels, YOLOv8x had the best performance. The area under the curve (AUC) of the YOLOv8x submodel was higher than that of the clinical model (internal test set: 0.990 vs 0.878, P =.002; external test set: 0.967 vs 0.912, P =.140) and that of all radiologists (P <.001). The YOLOv8x submodel, when compared with radiologist assessment, demonstrated higher sensitivity (internal test set: 100.0 % vs 70.7 %, P =.002; external test set: 96.0 % vs 68.8 %, P <.001) and specificity (internal test set: 90.7 % vs 66.0 %, P =.025; external test set: = 88.0 % vs 66.0 %, P <.001).

CONCLUSION

Using plain CT images, YOLOv8x was able to efficiently identify cases of SMA abnormalities. This could potentially improve early diagnosis accuracy and thus improve clinical outcomes.

Acute mesenteric ischemia: A case report

Acute mesenteric ischemia is a rare life-threatening diagnostic and therapeutic emergency. Lack of clinical and biological specificity makes the diagnosis difficult. Imaging, particularly computed tomography can help confirm the diagnosis. An underlying cause is identified in about 30%-70% of cases and should always be sought. We report a case of a 51-year-old man with chronic alcoholic liver disease admitted to the emergency department for abdominal pain. Computed tomography showed mesenteric venous thrombosis with signs of small bowel ischemia and cirrhosis with portal hypertension. Through this observation, we describe the imaging aspects of mesenteric ischemia and emphasize the necessity of seeking underlying pathological condition.

INT-767-A Dual Farnesoid-X Receptor (FXR) and Takeda G Protein-Coupled Receptor-5 (TGR5) Agonist Improves Survival in Rats and Attenuates Intestinal Ischemia Reperfusion Injury

Intestinal ischemia is a potentially catastrophic emergency, with a high rate of morbidity and mortality. Currently, no specific pharmacological treatments are available. Previous work demonstrated that pre-treatment with obeticholic acid (OCA) protected against ischemia reperfusion injury (IRI). Recently, a more potent and water-soluble version has been synthesized: Intercept 767 (INT-767). The aim of this study was to investigate if intravenous treatment with INT-767 can improve outcomes after IRI. In a validated rat model of IRI (60 min ischemia + 60 min reperfusion), three groups were investigated (n = 6/group): (i) sham: surgery without ischemia; (ii) IRI + vehicle; and (iii) IRI + INT-767. The vehicle (0.9% NaCl) or INT-767 (10 mg/kg) were administered intravenously 15 min after start of ischemia. Endpoints were 7-day survival, serum injury markers (L-lactate and I-FABP), histology (Park-Chiu and villus length), permeability (transepithelial electrical resistance and endotoxin translocation), and cytokine expression. Untreated, IRI was uniformly lethal by provoking severe inflammation and structural damage, leading to translocation and sepsis. INT-767 treatment significantly improved survival by reducing inflammation and preserving intestinal structural integrity. This study demonstrates that treatment with INT-767 15 min after onset of intestinal ischemia significantly decreases IRI and improves survival. The ability to administer INT-767 intravenously greatly enhances its clinical potential.

Prognostic factors after acute mesenteric ischemia: which patients require specific management?

PURPOSE

Diagnosis and treatment of AMI are a real issue for implicating physicians. In the literature, only one AMI stroke center has reported its results so far, with increasing survival rates. Our aim was to analyze acute mesenteric ischemia (AMI) related mortality and predictive factors, in a single academic center, before creating a dedicated intestinal stroke center.

METHODS

All the patients with an AMI, between January 2015 and December 2020, were retrospectively included. They were divided into 2 groups according to the early mortality: death during the first 30 days and alive. The 2 groups were compared.

RESULTS

173 patients (57% of men), were included, with a mean age of 68 ± 16 years. Overall mortality rate was 61%. Mortality occurred within the first 30 days in 78% of dead cases. Dead patients were significantly older, more frequently admitted from intensive care, with more serious clinical, laboratory and radiological characteristics. We have identified 3 protective factors - history of abdominal surgery (Odd Ratio = 0.1; 95%CI = 0.01-0.8, p = 0.03), medical management with curative anticoagulation (OR = 0.09; 95%CI = 0.02-0.5, p = 0.004) and/or antiplatelets (OR = 0.04; 95%CI = 0.006-0.3, p = 0.001)-, and 2 predictive factors of mortality - age > 70 years (OR = 7; 95%CI = 1.4-37, p = 0.02) and previous history of coronaropathy (OR = 13; 95%CI = 1.7-93, p = 0.01).

CONCLUSIONS

AMI is a severe disease with high morbidity and mortality rates. Even if its diagnosis is still difficult because of non-specific presentation, its therapeutic management needs to be changed in order to improve survival rates, particularly in patients older than 70 years with history of coronaropathy. Developing a dedicated organization would improve the diagnosis and the management of patients with AMI.

The Global Burden of Vascular Intestinal Disorders in 204 Countries and Territories From 1990 to 2019: Global Burden of Diseases Study

Objectives: Assess the prevalence, mortality, and disability-adjusted life years (DALYs) of vascular intestinal disorders (VID) from 1990 to 2019. Methods: This study conducted a secondary data analysis utilizing the Global Burden of Diseases Study 2019. The prevalence, mortality and DALYs of VID were analyzed by sex, age and socio-demographic index (SDI), respectively. Analyses were performed by using R software. Results: Globally, the number of prevalent VID cases increased from 100,158 (95% uncertainty interval: 89,428-114,013) in 1,990-175,740 (157,941-198,969) in 2019. However, the age-standardized rates (ASR) of VID prevalence declined from 2.47 (95% uncertainty interval: 2.24-2.76) per 100,000 population to 2.21 (1.98-2.48) per 100,000 population between 1990 and 2019. Furthermore, the ASR of mortality also decreased from 1990 to 2019. Between 1990 and 2019, the regions with high and high-middle level exhibited the highest diseases burden. Conclusion: Globally, the diseases burden associated with VID demonstrated a decline from 1990 to 2019. However, concerted efforts are still required to enhance measures to combat VID within countries categorized as high and high-middle SDI.

Intravenous Polyethylene Glycol Alleviates Intestinal Ischemia-Reperfusion Injury in a Rodent Model

Intestinal ischemia-reperfusion injury (IRI) is a common clinical entity, and its outcome is unpredictable due to the triad of inflammation, increased permeability and bacterial translocation. Polyethylene glycol (PEG) is a polyether compound that is extensively used in pharmacology as an excipient in various products. More recently, this class of products have shown to have potent anti-inflammatory, anti-apoptotic, immunosuppressive and cell-membrane-stabilizing properties. However, its effects on the outcome after intestinal IRI have not yet been investigated. We hypothesized that PEG administration would reduce the effects of intestinal IRI in rodents. In a previously described rat model of severe IRI (45 min of ischemia followed by 60 min of reperfusion), we evaluated the effect of IV PEG administration at different doses (50 and 100 mg/kg) before and after the onset of ischemia. In comparison to control animals, PEG administration stabilized the endothelial glycocalyx, leading to reduced reperfusion edema, bacterial translocation and inflammatory reaction as well as improved 7-day survival. These effects were seen both in a pretreatment and in a treatment setting. The fact that this product is readily available and safe should encourage further clinical investigations in settings of intestinal IRI, organ preservation and transplantation.

Improving clinical suspicion of acute mesenteric ischemia among patients with acute abdomen: a cross-sectional study from an intestinal stroke center

BACKGROUND

Early diagnosis of acute mesenteric ischemia (AMI) is essential for a favorable outcome. Selection of patients requiring a dedicated multiphasic computed tomography (CT) scan remains a clinical challenge.

METHODS

In this cross-sectional diagnostic study conducted from 2016 to 2018, we compared the presentation of AMI patients admitted to an intestinal stroke center to patients with acute abdominal pain of another origin admitted to the emergency room (controls).

RESULTS

We included 137 patients-52 with AMI and 85 controls. Patients with AMI [median age: 65 years (interquartile range 55-74)] had arterial and venous AMI in 65% and 35% of cases, respectively. Relative to controls, AMI patients were significantly older, more likely to have risk factors or a history of cardiovascular disease, and more likely to present with sudden-onset and morphine-requiring abdominal pain, hematochezia, guarding, organ dysfunction, higher white blood cell and neutrophil counts, and higher plasma C-reactive protein (CRP) and procalcitonin concentrations. On multivariate analysis, two independent factors were associated with the diagnosis of AMI: the sudden-onset (OR = 20, 95%CI 7-60, p < 0.001) and the morphine-requiring nature of the acute abdominal pain (OR = 6, 95%CI 2-16, p = 0.002). Sudden-onset and/or morphine-requiring abdominal pain was present in 88% of AMI patients versus 28% in controls (p < 0.001). The area under the receiver operating characteristic curve for the diagnosis of AMI was 0.84 (95%CI 0.77-0.91), depending on the number of factors.

CONCLUSIONS

Sudden onset and the need for morphine are suggestive of AMI in patients with acute abdominal pain and should prompt multiphasic CT scan including arterial and venous phase images for confirmation.

Antibiotic use in acute mesenteric ischemia: a review of the evidence and call to action

Acute mesenteric ischemia (AMI) is a life-threatening condition with a high mortality rate. The standard practice after making the diagnosis includes aggressive resuscitation, anticoagulation, followed by revascularization and resection of necrotic bowel. The role of empiric antibiotics in the management of AMI is not well defined in the literature. This review article aims to examine our current understanding on this matter, based on bench research and clinical studies. It is demonstrated in animal study model that the ischemia/reperfusion (I/R) injury damages intestinal epithelium, and subsequently lead to barrier dysfunction, a condition that can support bacterial translocation through a complex interplay between the intestinal epithelium, the intestinal immune system and the intestine's endogenous bacterial population. Based on this mechanism, it is possible that the use of antibiotics may help mitigate the consequences of I/R injury, which is examined in few animal studies. In clinical practice, many guidelines support the use of prophylactic antibiotics, based on a meta-analysis of randomized control trials (RCTs) demonstrating the benefit of antibiotics in multi-organ dysfunction syndrome. However, there is no direct reference to AMI in this meta-analysis. Most clinical studies that focus on AMI and mentions the use of antibiotics are retrospective and single institution, and very few comments on the role of antibiotics in their discussions. We conclude that there is limited evidence in literature to support the use of prophylactic antibiotic in AMI to improve outcome. More clinical studies with high level of evidence and basic science research are needed to improve our understanding on this topic and ultimately help build a better clinical pathway for patients with AMI.

Management of acute mesenteric ischaemia: Results of a worldwide survey

BACKGROUND

Acute mesenteric ischaemia (AMI) is a condition with high mortality. This survey assesses current attitudes and practices to manage AMI worldwide.

METHODS

A questionnaire survey about the practices of diagnosing and managing AMI, endorsed by several specialist societies, was sent to different medical specialists and hospitals worldwide. Data from individual health care professionals and from medical teams were collected.

RESULTS

We collected 493 individual forms from 71 countries and 94 team forms from 34 countries. Almost half of respondents were surgeons, and most of the responding teams (70%) were led by surgeons. Most of the respondents indicated that diagnosis of AMI is often delayed but rarely missed. Emergency revascularisation is often considered for patients with AMI but rarely in cases of transmural ischaemia (intestinal infarction). Responses from team hospitals with a dedicated special unit (14 team forms) indicated more aggressive revascularisation. Abdominopelvic CT-scan with intravenous contrast was suggested as the most useful diagnostic test, indicated by approximately 90% of respondents. Medical history and risk factors were thought to be more important in diagnosis of AMI without transmural ischaemia, whereas for intestinal infarction, plasma lactate concentrations and surgical exploration were considered more useful. In elderly patients, a palliative approach is often chosen over extensive bowel resection. There was a large variability in anticoagulant treatment, as well as in timing of surgery to restore bowel continuity.

CONCLUSIONS

Delayed diagnosis of AMI is common despite wide availability of an adequate imaging modality, i.e. CT-scan. Large variability in treatment approaches exists, indicating the need for updated guidelines. Increased awareness and knowledge of AMI may improve current practice until more robust evidence becomes available. Adherence to the existing guidelines may help in improving differences in treatment and outcomes.

Mortality and Delays of Management of Acute Mesenteric Ischemia: The Need of a Dedicated Program

BACKGROUND

To study the mortality and delays of management of patients with acute mesenteric ischemia (AMI) admitted to the emergency department of a tertiary hospital and identify risk factors for 1-month mortality.

METHODS

A single-center and retrospective study including all consecutive patients treated for AMI from January 2008 to December 2018 was conducted. Short- and medium-term survival was studied with a Kaplan-Meier analysis. Delays before diagnosis and surgical intervention were collected. To determine factors associated with mortality at 1 month postoperatively, univariate and multivariate analyzes were performed.

RESULTS

The survival rate of the 67 included patients was 55.22% at 1 month and 37.31% at 1 year. In-hospital mortality was 50.74%. The average delay between admission and diagnosis was 4.83 ± 5.03 hr (95% confidence interval [CI], 3.60-6.05), and the delay between admission and surgical treatment was 10.64 ± 8.80 hr (95% CI, 8.49-12.79). The independent variables associated with an increased mortality at 1 month postoperatively in the univariate analysis were age >65 years old (odds ratio [OR] = 3.52; P = 0.046), lactate >3.31 mmol/l at admission (H₀) (OR = 7.38; P < 0.001), lactate >3.32 mmol/l on day 1 (H₂₄) (OR = 5.60; P = 0.002), creatinine >95.9 μmol/l at H₀ (OR = 4.66; P = 0.004), aspartate aminotransferase (AST) >59 U/l at H₀ (OR = 3.55; P = 0.017), and having hypertension as comorbidity (OR = 9.32; P = 0.040). Early curative anticoagulation (z = -2.4; P = 0.016) was an independent protective factor for mortality, and lactate >3.31 mmol/l at H₀ (z = 2.62; P = 0.009) was an independent predictor factor of mortality at 1 month postoperatively in the multivariate analysis.

CONCLUSION

AMI remains a serious and lethal condition with delays of surgical management remaining too long due to a lack of a dedicated therapeutic protocol allowing an early diagnosis.

Reperfusion injury on computed tomography following endovascular revascularization of acute mesenteric ischemia: prevalence, risk factors, and patient outcome

BACKGROUND

Data about reperfusion injury (RI) following acute arterial mesenteric ischemia (AAMI) in humans are scarce. We aimed to assess the prevalence and risk factors of RI following endovascular revascularization of AMI and evaluate its impact on patient outcomes.

METHODS

Patients with AAMI who underwent endovascular revascularization (2016-2021) were included in this retrospective cohort. CT performed < 7 days after treatment was reviewed to identify features of RI (bowel wall hypoattenuation, mucosal hyperenhancement). Clinical, laboratory, imaging, and treatments were compared between RI and non-RI patients to identify factors associated with RI. Resection rate and survival were also compared.

RESULTS

Fifty patients (23 men, median 72-yrs [IQR 60-77]) were included, and 22 were diagnosed with RI (44%) after a median 28 h (22-48). Bowel wall hypoattenuation and mucosal hyperenhancement were found in 95% and 91% of patients with post-interventional RI, respectively. Patients with RI had a greater increase of CRP levels after endovascular treatment (p = 0.01). On multivariate analysis, a decreased bowel wall enhancement on baseline CT (HR = 8.2), an embolic cause (HR = 7.4), complete SMA occlusion (HR = 7.0), and higher serum lactate levels (HR = 1.4) were associated with RI. The three-month survival rate was 78%, with no difference between subgroups (p = 0.99). However, the resection rate was higher in patients with RI (32% versus 7%; p = 0.03).

CONCLUSION

RI is frequent after endovascular revascularization of AAMI, especially in patients who present with decreased bowel wall enhancement on pre-treatment CT, an embolic cause, and a complete occlusion of the SMA. However, its occurrence does not seem to negatively impact short-term survival.

Acute Isolated Mesenteric Artery Dissection: Four Year Experience From a French Intestinal Stroke Centre

OBJECTIVE

This study aimed to report outcomes of patients with symptomatic acute isolated mesenteric artery dissection (IMAD) treated within a French intestinal stroke centre (ISC).

METHODS

All patients with symptomatic IMAD referred to the ISC from January 2016 to January 2020 were included prospectively. Patients with aortic dissection and asymptomatic IMAD were not included. The standardised medical protocol included anticoagulation and antiplatelet therapy, gastrointestinal resting, and oral antibiotics. Operations were considered for acute mesenteric ischaemia (AMI).

RESULTS

Among the 453 patients admitted to an ISC during the study period, 34 (median age, 53 years [41 - 67]; 82% men) with acute symptomatic IMAD were included. According to the classification of Yun et al., IMADs were reported as follows: type I (n = 7, 20%), type IIa (n = 6, 18%), type IIb (n = 15, 44%), and type III (i.e., complete superior mesenteric artery [SMA] occlusion; n = 6, 18%). Overall, nine (26%) patients had AMI (type I/II, n = 3; type III, n = 6). On initial computerised tomography angiogram, nine (26%) patients had an associated visceral arterial dissection or pseudoaneurysm. All patients with types I/II (n = 28, 82%) followed a favourable clinical course with conservative therapy, with no need for any operation. All patients with type III (n = 6, 18%) underwent urgent laparotomy with SMA revascularisation (open, n = 4; stenting, n = 1) and or bowel resection (early, n = 3; late, n = 1). Rates of intestinal resection and short bowel syndrome were 12% and 8.8%, respectively. After a median follow up of 26 months [18 - 42], recurrence of symptoms occurred in four (12%) patients and aneurysmal change in 14 (41%), with no re-intervention.

CONCLUSION

Although IMAD was associated with a high frequency of AMI, a standardised protocol produced a low rate of intestinal resection. Conservative therapy seems appropriate in types I/II patients, whereas urgent SMA revascularisation should aim to avoid intestinal resection or death in type III patients.

Incidence and outcomes of acute mesenteric ischaemia: a systematic review and meta-analysis

OBJECTIVE

To estimate the incidence of acute mesenteric ischaemia (AMI), proportions of its different forms and short-term and long-term mortality.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

MEDLINE (Ovid), Web of Science, Scopus and Cochrane Library were searched until 26 July 2022.

ELIGIBILITY CRITERIA

Studies reporting data on the incidence and outcomes of AMI in adult populations.

DATA EXTRACTION AND SYNTHESIS

Data extraction and quality assessment with modified Newcastle-Ottawa scale were performed using predeveloped standard forms. The outcomes were the incidence of AMI and its different forms in the general population and in patients admitted to hospital, and the mortality of AMI in its different forms.

RESULTS

From 3064 records, 335 full texts were reviewed and 163 included in the quantitative analysis. The mean incidence of AMI was 6.2 (95% CI 1.9 to 12.9) per 100 000 person years. On average 5.0 (95% CI 3.3 to 7.1) of 10 000 hospital admissions were due to AMI. Occlusive arterial AMI was the most common form constituting 68.6% (95% CI 63.7 to 73.2) of all AMI cases, with similar proportions of embolism and thrombosis.Overall short-term mortality (in-hospital or within 30 days) of AMI was 59.6% (95% CI 55.5 to 63.6), being 68.7% (95% CI 60.8 to 74.9) in patients treated before the year 2000 and 55.0% (95% CI 45.5 to 64.1) in patients treated from 2000 onwards (p<0.05). The mid/long-term mortality of AMI was 68.2% (95% CI 60.7 to 74.9). Mortality due to mesenteric venous thrombosis was 24.6% (95% CI 17.0 to 32.9) and of non-occlusive mesenteric ischaemia 58.4% (95% CI 48.6 to 67.7). The short-term mortality of revascularised occlusive arterial AMI was 33.9% (95% CI 30.7 to 37.4).

CONCLUSIONS

In adult patients, AMI is a rarely diagnosed condition with high mortality, although with improvement of treatment results over the last decades. Two thirds of AMI cases are of occlusive arterial origin with potential for better survival if revascularised.

PROSPERO REGISTRATION NUMBER

CRD42021247148.

Acute mesenteric ischemia: updated guidelines of the World Society of Emergency Surgery

Acute mesenteric ischemia (AMI) is a group of diseases characterized by an interruption of the blood supply to varying portions of the intestine, leading to ischemia and secondary inflammatory changes. If untreated, this process may progress to life-threatening intestinal necrosis. The incidence is low, estimated at 0.09-0.2% of all acute surgical admissions, but increases with age. Although the entity is an uncommon cause of abdominal pain, diligence is required because if untreated, mortality remains in the range of 50%. Early diagnosis and timely surgical intervention are the cornerstones of modern treatment to reduce the high mortality associated with this entity. The advent of endovascular approaches in parallel with modern imaging techniques is evolving and provides new treatment options. Lastly, a focused multidisciplinary approach based on early diagnosis and individualized treatment is essential. Thus, we believe that updated guidelines from World Society of Emergency Surgery are warranted, in order to provide the most recent and practical recommendations for diagnosis and treatment of AMI.

Predictors of transmural intestinal necrosis in patients presenting with acute mesenteric ischemia on computed tomography

PURPOSE

The purpose of this study was to identify the significant imaging predictors of transmural intestinal necrosis in patients with acute mesenteric ischemia (AMI).

METHODS

The medical records and CT imaging of 48 patients between 2011 and 2019 suspected of having AMI that underwent exploratory laparotomy with bowel resection and pathological confirmation of ischemic bowel injury were retrospectively reviewed. Using histopathology as a gold standard, various parameters related to vascular insufficiency and bowel injury were analyzed and correlated with outcome of ischemic bowel necrosis using nonparametric tests. Univariate analysis was performed using Fisher's exact test followed by binary logistic regression test for multivariate analysis.

RESULTS

48 Patients (19 females, 40%) with a median age of 68.5 years (IQR of 17 years) built our retrospective cohort. 26 (54%) patients were found to have transmural intestinal necrosis on histopathology (case group) whereas 22 (46%) patients had partial mucosal injury (control group). Pneumatosis intestinalis (p = 0.005, odd's ratio of 2.07-63.14) and severity (> 70% or complete occlusion) of vascular narrowing (p = 0.019, odd's ratio of 1.39-42.30) were identified as the most significant predictors of transmural ischemic necrosis on imaging. Dilatation of bowel did not approach the statistical significance on multivariate analysis although it was found significant on univariate analysis (p = 0.041).

CONCLUSION

Pneumatosis intestinalis and severity of vascular luminal narrowing are the most important imaging predictors of transmural ischemic bowel necrosis in patients presenting with AMI. The presence of these findings on CT scan should raise high index of suspicion for irreversible transmural ischemic necrosis. In the absence of these factors, endovascular management might be beneficial.

Colonic involvement in acute mesenteric ischemia: prevalence, risk factors, and outcomes

OBJECTIVES

This study aimed to investigate the prevalence, risk factors, and outcomes of colonic involvement in patients with acute mesenteric ischemia (AMI).

METHODS

CT scans from a prospective cohort of 114 AMI patients treated in an intestinal stroke center between 2009 and 2018 were blindly reviewed by two radiologists. Colon involvement was defined on CT scan by the presence of at least one of the following CT colonic features: wall thickening, pneumatosis, decreased wall enhancement, dilatation, or perforation. In addition, the clinical, biological, and radiological characteristics of patients with and without colonic involvement were compared to identify risk factors for colonic involvement on CT and its impact on morbidity and mortality.

RESULTS

Colonic involvement was identified in 32/114 (28%) patients with AMI, the right colon being more frequently involved (n = 29/32, 91%). Wall thickening (n = 27/32) was the most common CT finding. Occlusion of the inferior mesenteric artery was the only statistically significant risk factor for colonic involvement (35% vs. 15%, p = 0.02). Patients with colonic involvement on CT vs. those without had more frequently transmural colonic necrosis (13% vs. 0%, p = 0.006), short bowel syndrome (16% vs. 4%, p = 0.04), need for long-term parenteral support (19% vs. 5%, p = 0.03), and death during follow-up (22% vs. 10%, p = 0.03).

DISCUSSION

In patients with AMI, colonic involvement is associated with increased morbidity and mortality and should be carefully searched for during initial CT scan assessment.

KEY POINTS

• In a prospective cohort of acute mesenteric ischemia patients from an intestinal stroke center, 28% had an associated colonic involvement on CT. • Colonic involvement on CT most commonly affected the right colon, and the occlusion of the inferior mesenteric artery was the only risk factor. • Colonic involvement on CT was associated with increased morbidity and mortality and should be carefully searched for during initial CT scan assessment.

Endovascular revascularization of acute arterial mesenteric ischemia: report of a 3-year experience from an intestinal stroke center unit

OBJECTIVE

To report the 3-year experience of endovascular revascularization of acute arterial mesenteric ischemia (AMI) from an intestinal stroke center unit (ISCU).

METHOD

All data from patients admitted to the ISCU between January 2016 and January 2019 for arterial AMI who underwent endovascular recanalization were prospectively acquired and retrospectively analyzed. Patient demographics, clinical and laboratory characteristics at presentation, and CT scans were reviewed. The type (thrombolysis, thrombectomy, stenting) and the outcome of endovascular procedures (technical success or failure, complications) were noted. Care pathways were described focusing on post-procedural treatments (surgical revascularization, bowel resection) and the mortality rate was evaluated in subgroups.

RESULTS

Fifty-eight patients (34 men [59%], mean 69 ± 29 years) were included. Endovascular revascularization was technically successful in 51/58 (88%) patients, and 10 (17%) patients had post-procedural complications. Stenting and in situ thrombolysis were performed in most patients (n = 33 and n = 19, respectively). Thirty-two patients (55%) were recurrence-free and required no further treatment after the procedure, while 9 (16%), 5 (9%), and 5 (9%) patients underwent 2nd-line bowel resection, surgical revascularization, or both. Overall, 46 (79%), 45 (78%), and 34 patients (63%) were alive at 3 months, 1 year, and 3 years. No significant difference in survival was found in care pathways or baseline characteristics.

CONCLUSION

Endovascular revascularization is highly feasible for the treatment of arterial AMI, and is associated with an acceptable rate of complications. Results of endovascular revascularization shall only be interpreted as part of a multidisciplinary patient management strategy.

KEY POINTS

• Endovascular revascularization is highly feasible for the treatment of arterial AMI, and is associated with an acceptable rate of complications. • Several techniques are available to perform endovascular revascularization, and their use depends on the cause, the location, and the quality of underlying arteries of patients. • Results of endovascular revascularization shall only be interpreted in relation to its role in an integrated multidisciplinary and patient management strategy.

Accuracy of citrulline, I-FABP and D-lactate in the diagnosis of acute mesenteric ischemia

Early diagnosis of acute mesenteric ischemia (AMI) remains a clinical challenge, and no biomarker has been consistently validated. We aimed to assess the accuracy of three promising circulating biomarkers for diagnosing AMI-citrulline, intestinal fatty acid-binding protein (I-FABP), and D-lactate. A cross-sectional diagnostic study enrolled AMI patients admitted to the intestinal stroke center and controls with acute abdominal pain of another origin. We included 129 patients-50 AMI and 79 controls. Plasma citrulline concentrations were significantly lower in AMI patients compared to the controls [15.3 μmol/L (12.0-26.0) vs. 23.3 μmol/L (18.3-29.8), p = 0.001]. However, the area under the receiver operating curves (AUROC) for the diagnosis of AMI by Citrulline was low: 0.68 (95% confidence interval = 0.58-0.78). No statistical difference was found in plasma I-FABP and plasma D-lactate concentrations between the AMI and control groups, with an AUROC of 0.44, and 0.40, respectively. In this large cross-sectional study, citrulline, I-FABP, and D-lactate failed to differentiate patients with AMI from patients with acute abdominal pain of another origin. Further research should focus on the discovery of new biomarkers.

Multidisciplinary management of acute mesenteric ischemia: Surgery and endovascular intervention

Acute mesenteric ischemia (AMI) is a rare cause of the “acute abdomen”, characterized by impaired blood flow to the intestine. The principle of treatment is restoration of perfusion to ischemic bowel and resection of any necrotic intestine. Surgery and endovascular intervention are two complementary approaches to mesenteric ischemia. Endovascular intervention is not an alternative to the surgical approach, but it has the potential to improve the prognosis of patients with AMI when judiciously combined with a surgical approach. Due to the need for emergent treatment of patients with acute mesenteric ischemia, the treatment strategy needs to be modified for each facility. This review aims to highlight cutting-edge studies and provide reasonable treatment strategies for patients with acute mesenteric ischemia based on available evidence.

Non-occlusive mesenteric ischemia: Diagnostic challenges and perspectives in the era of artificial intelligence

Acute mesenteric ischemia (AMI) is a severe condition associated with poor prognosis, ultimately leading to death due to multiorgan failure. Several mechanisms may lead to AMI, and non-occlusive mesenteric ischemia (NOMI) represents a particular form of AMI. NOMI is prevalent in intensive care units in critically ill patients. In NOMI management, promptness and accuracy of diagnosis are paramount to achieve decisive treatment, but the last decades have been marked by failure to improve NOMI prognosis, due to lack of tools to detect this condition. While real-life diagnostic management relies on a combination of physical examination, several biomarkers, imaging, and endoscopy to detect the possibility of several grades of NOMI, research studies only focus on a few elements at a time. In the era of artificial intelligence (AI), which can aggregate thousands of variables in complex longitudinal models, the prospect of achieving accurate diagnosis through machine-learning-based algorithms may be sought. In the following work, we bring you a state-of-the-art literature review regarding NOMI, its presentation, its mechanics, and the pitfalls of routine work-up diagnostic exams including biomarkers, imaging, and endoscopy, we raise the perspectives of new biomarker exams, and finally we discuss what AI may add to the field, after summarizing what this technique encompasses.

Maintaining oxygen delivery is crucial to prevent intestinal ischemia in critical ill patients

BACKGROUND

Intestinal ischemia is a common complication with obscure pathophysiology in critically ill patients. Since insufficient delivery of oxygen is discussed, we investigated the influence of oxygen delivery, hemoglobin, arterial oxygen saturation, cardiac index and the systemic vascular resistance index on the development of intestinal ischemia. Furthermore, we evaluated the predictive power of elevated lactate levels for the diagnosis of intestinal ischemia.

METHODS

In a retrospective case-control study data (mean oxygen delivery, minimum oxygen delivery, systemic vascular resistance index) of critical ill patients from 02/2009-07/2017 were analyzed using a proportional hazard model. General model fit and linearity were tested by likelihood ratio tests. The components of oxygen delivery (hemoglobin, arterial oxygen saturation and cardiac index) were individually tested in models.

RESULTS

59 out of 874 patients developed intestinal ischemia. A mean oxygen delivery less than 250ml/min/m2 (LRT vs. null model: p = 0.018; LRT for non-linearity: p = 0.012) as well as a minimum oxygen delivery less than 400ml/min/m2 (LRT vs null model: p = 0.016; LRT for linearity: p = 0.019) were associated with increased risk of the development of intestinal ischemia. We found no significant influence of hemoglobin, arterial oxygen saturation, cardiac index or systemic vascular resistance index. Receiver operating characteristics analysis for elevated lactate levels, pH, CO2 and central venous saturation was poor with an area under the receiver operating characteristic of 0.5324, 0.52, 0.6017 and 0.6786.

CONCLUSION

There was a significant correlation for mean and minimum oxygen delivery with the incidence of intestinal ischemia for values below 250ml/min/m2 respectively 400ml/min/m2. Neither hemoglobin, arterial oxygen saturation, cardiac index, systemic vascular resistance index nor elevated lactate levels could be identified as individual risk factors.

Relationship of superior mesenteric artery thrombus density with transmural intestinal necrosis on multidetector computed tomography in acute mesenteric ischemia

Background

Acute arterial occlusive mesenteric ischemia with transmural intestinal necrosis (TIN) is a fatal disease, which is difficult to diagnose on multidetector computed tomography (MDCT). The aim of the present study was to determine the relationship of superior mesenteric artery (SMA) thrombus density with TIN on MDCT in patients with acute mesenteric ischemia (AMI) due to SMA thromboembolism.

Methods

In this retrospective study, 33 patients who underwent abdominal MDCT and angiography for AMI due to SMA thromboembolism were divided into two groups: the AMI with TIN group and the AMI without TIN group. We analyzed the relationships of clinical characteristics, qualitative MDCT signs, and SMA thrombus density with TIN. The SMA thrombus density was measured on non-contrast MDCT. Univariate and multivariate analyses were performed to determine the risk factors for predicting TIN. The diagnostic performances of risk factors were evaluated by receiver-operating characteristic (ROC) curve analysis.

Results

Of the patients with AMI enrolled in this study, 33.3% (11/33) were diagnosed with TIN. Peritonitis (P=0.042), bowel wall thinning (P=0.033), and pneumatosis/portomesenteric gas (P=0.010) were significantly associated with TIN. AMI patients with TIN exhibited a higher SMA thrombus density than AMI patients without TIN [41.2±6.1 vs. 34.2±3.0 Hounsfield unit (HU), P=0.003]. Multivariate analysis showed that SMA thrombus density was an independent predictor of TIN [P=0.044, hazard ratio (HR): 1.82, 95% confidence interval (CI): 1.02-3.25]. For diagnosing AMI with TIN, the area under the ROC curve (AUC) of SMA thrombus density (0.83) was larger than those of peritonitis (0.68), bowel wall thinning (0.66), and pneumatosis/portomesenteric gas (0.71).

Conclusions

In patients with AMI, erythrocyte-rich thrombus blocking the SMA trunk which has a higher density on MDCT is prone to the occurrence of TIN compared with erythrocyte-scarce thrombus with a lower density. SMA thrombus density could be an independent risk factor for TIN in patients with AMI due to SMA thromboembolism.

Early Surgical Intervention Improves Survival in Acute Intestinal Ischemia in the Intensive Care Unit

The study is aimed at assessing whether the early surgical intervention improves survival in acute mesenteric ischemia with septic shock. A retrospective study design was applied to review the charts of patients admitted to the intensive care unit. The data were collected through a review of the full patient chart including physician and nursing notes, pathology reports, intraoperative findings, CT findings, and endoscopy. The diagnosis of AMI for each patient was determined through clinical presentation/endoscopic visualization/laboratory results/radiographic imaging, surgical exam (tissue or visual) and/or autopsy. Death and survival were evaluated between short and long-time-interval for septic shock groups using the chi-square test followed by calculating the P value. Total survival among the surgery group was 60 patients (95.24%) compared to 3 (4.76%) survival among patients who did not have surgery. The time from the onset of a shock to the time of surgical incision was calculated. The mean time to surgery was 17.7 hours. Total 65 patients (29.52%) had surgery between 4 and 12 hours from the onset of hypotension. Survivals among this group of patients were 41.7% (n = 25). The survival difference was statistically significant than died patients with respect to the time of surgical intervention (P = <0.001). Early removal of ischemic bowel in patients with AII-related surgery has improved survival.

Evolution in the Presentation, Treatment, and Outcomes of Patients with Acute Mesenteric Ischemia

OBJECTIVES

Acute mesenteric ischemia (AMI) is a life-threatening condition associated with dismal outcomes. This study sought to evaluate the evolution of presentation, treatment, and outcomes of AMI over the past two decades.

METHODS

AMI patients presenting at a single institution were reviewed (1993-2016). Venous thrombosis patients were excluded. Primary outcome was 30-day mortality. Patients were stratified by etiology and diagnosis date (before 2004 versus 2004 and later). Ordered logistic regression was performed for longitudinal temporal analysis.

RESULTS

303 patients were identified. AMI mechanisms included: embolic (49%), thrombotic (29%), and non-occlusive (NOMI) (22%). The majority were women (55%), 50% had atrial fibrillation, and 23% were on anticoagulation (AC) therapy. Mean age was 72±13 years. 345 procedures were performed in 242 patients: 321 open and 24 hybrid/endovascular. Among the 189 embolic/thrombotic patients who were managed operatively, 45% (n=85) underwent mesenteric revascularization while 39 (21%) had findings of non-survivable bowel necrosis (NSBN). Among the 104 patients who did not undergo revascularization, 64 (62%) died within 30-days compared to 36 out of 85 (42%) patients who were revascularized (P=0.01). 30-day mortality was 61% and stable over time (P=0.91); when stratified by AMI etiology, the thrombotic cohort had worse survival than embolic and NOMI patients (P=0.04). Since 2000, there was a significant decrease in the percentage of embolic AMI events (P=0.04). The percentage of patients who underwent operative management decreased also over time (P=0.01, 81% → 61%), which was correlated with an increasing number of patients being made comfort measures only (CMO) prior to surgical intervention (50% → 70%, P=0.02). The majority of patients (55%) were ultimately made CMO during their hospitalization. Predictors of 30-day mortality included a preoperative white blood cell count (WBC) ≥ 25 K/ µL. (OR 3.0, P=0.002) and lactate ≥ 2.3 mmol/L (OR 2.8, P=0.045). NSBN predictors included WBC ≥ 24 K/ µL. (OR 3.4 P=0.03) and lactate ≥ 3.8 mmol/L (OR 3.6, P=0.04).

CONCLUSIONS

Despite advances in critical care over the past 25 years, AMI continues to be associated with poor prognosis. The survival benefit observed in patients who undergo revascularization supports an aggressive approach towards early vascular intervention, although this requires further study. The importance of early diagnosis, prognostication and advanced directives is highlighted given the high morbidity, mortality and use of comfort measures associated with AMI.

A Comprehensive Way to Access Hospital Death Prediction Model for Acute Mesenteric Ischemia: A Combination of Traditional Statistics and Machine Learning

Purpose

This study aimed to use traditional statistics and machine learning to develop and validate prediction models for predicting hospital death in patients with AMI and compare these models' performance.

Patients and Methods

Data were retrieved from the Medical Information Mart for Intensive Care (MIMIC III) electronic clinical database. A total of 338 eligible AMI patients were divided into a training cohort (n = 238) and a validation cohort (n = 100), and all patients were divided into survival groups and nonsurvival groups according to patients' hospital outcomes. The performance of the traditional statistics prediction model and the optimal machine learning prediction model was evaluated and compared with respect to discrimination, calibration, and clinical utility in the validation cohort.

Results

Univariate and multivariate logistic regression analyses identified the following independent risk factors associated with hospital death for AMI in the training cohort, including diastolic blood pressure, blood lactate, blood creatinine, age, blood pH, and red blood cell distribution width. Both the nomogram (AUC = 77.0%, 67.9-86.1%) and optimal machine learning model (AUC = 82.9%, 74.9-91.0%) achieved good discrimination and calibration in the validation cohort. Decision curves analysis showed that the optimal machine learning model has a greater net benefit than that of nomogram in this study.

Conclusion

The nomogram achieved a concise and relatively accurate prediction of hospital death in patients with AMI, the machine learning model also has good discrimination and seems to have better clinical utility. Traditional statistics may help infer the relationship between risk factors and hospital death, while machine learning may contribute to a more accurate prediction. Traditional statistics and machine learning are complementary in developing the prediction model for hospital death of AMI. Therefore, a combination of nomogram-machine learning (Nomo-ML) predictive model may improve care and help clinicians make AMI management-related decisions.

Predictors and risk factors for intestinal necrosis in patients with mesenteric ischemia

Background

Mesenteric ischemia results in blood flow that is insufficient to meet metabolic demands and subsequent dysfunction of visceral organs, including arterial obstruction and venous thrombosis. Sustained mesenteric ischemia exhausts the ability of capillaries to provide oxygen and initiate an inflammatory reaction, and eventually leads to intestinal mucosal necrosis, a serious and potentially life-threatening condition. Therefore, it is essential that the predictors and risk factors for intestinal necrosis in patients with mesenteric thrombus are explored.

Methods

This study retrospectively enrolled 41 patients with mesenteric ischemia (including mesenteric vein embolism, mesenteric artery thrombosis, and portal vein thrombosis) who were admitted to the Department of Gastrointestinal Surgery, Beijing Tsinghua Changgung Hospital between May 2016 and October 2019; of the patients, 18 were further diagnosed with intestinal necrosis. Comparisons of symptoms, computed tomography angiography (CTA) features, and laboratory examination results were performed between mesenteric ischemia patients with and without intestinal necrosis.

Results

White blood cell count showed an excellent predictive ability for intestinal necrosis in patients with mesenteric ischemia, with an area under the receiver operating characteristic (ROC) curve of 0.772 (P=0.009). The four CTA features [pneumatosis (P=0.016), intestinal swelling (P=0.006), ascitic fluid (P<0.001), and decreased intestinal wall enhancement (P=0.004)] differed significantly between patients with and without intestinal necrosis. Peritonitis showed a strong association with intestinal necrosis (P=0.006) in the univariate analysis, and multivariate analysis further showed their association [odds ratio (OR): 8.53; 95%CI: 1.46-49.81; P=0.017].

Conclusions

White blood cell count is a potential predictor of intestinal necrosis. Peritonitis is a possible risk factor for intestinal necrosis in patients with mesenteric ischemia. A multi-center prospective study with a larger sample size needs to be performed to further investigate these findings.

Dexmedetomidine Resists Intestinal Ischemia-Reperfusion Injury by Inhibiting TLR4/MyD88/NF-κB Signaling

BACKGROUND

Intestinal ischemia/reperfusion (I/R) is a common clinical problem that occurs during various clinical pathological processes. Dexmedetomidine (DEX), a widely used anesthetic adjuvant agent, can induce protection against intestinal I/R in vivo; however, the underlying mechanism is not fully understood. In the present study, we aimed to investigate the protective effects of DEX and examine whether its mechanism was associated with the TLR4/MyD88/NF-κB signaling pathway.

METHODS

Sprague-Dawley rats were pretreated with DEX and then subjected to I/R-induced intestinal injury. In vivo, intestinal histopathological examination and scoring were performed, the levels of serum intestinal fatty acid-binding protein (I-FABP), intestinal tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and expression levels of TLR4, MyD88, and NF-κB in the intestine were determined. In in vitro experiments, the human colon carcinoma cell line (Caco-2) was incubated with DEX before deprivation/reoxygenation (OGD/R) treatment. The cell viability of Caco-2 cells, the levels of lactate dehydrogenase (LDH), TNF-α, and IL-1β in the supernatant, as well as protein expression of TLR4, MyD88, and NF-κB in Caco-2 cells, were measured. Statistical analysis was performed using SPSS version 21.0.

RESULTS

DEX preconditioning significantly reduced the intestinal pathological Chiu's score, serum I-FABP, intestinal TNF-α, IL-1β levels, and the protein expression of TLR4, MyD88, and NF-κB in the rats with intestinal I/R injury. Similarly, in vitro, DEX pretreatment protected against OGD/R-induced Caco-2 cell damage and inhibited TLR4/MyD88/NF-κB signaling, as evidenced by increased cell viability, decreased LDH activity, reduced TNF-α and IL-1β levels, as well as downregulated TLR4, MyD88, and NF-κB protein levels.

CONCLUSIONS

Our findings suggested that DEX could reduce intestinal I/R injury in rats and OGD/R damage in Caco-2 cells, and this protection might be attributed to antiinflammatory effects and inhibition of the TLR4/MyD88/NF-κB signaling pathway.

Revascularization of Isolated Superior Mesenteric Artery Dissection for Post-Mesenteric Infarction Exudative Enteropathy: The Contribution of a Multidisciplinary Care Teamwork

BACKGROUND

Isolated dissection of the superior mesenteric artery (SMA) is increasingly diagnosed; the conservative treatment appears to be the best option when blood supply is maintained. However, some patients require a more invasive attitude, due to acute or chronic ischemic complication. Multidisciplinary care within a health-care network improves medical and surgical support. We present a case of chronic complication of isolated SMA dissection requiring a revascularization, followed by bowel resection.

CASE PRESENTATION

A 49-year-old man presented abdominal pain secondary to necrotizing enterocolitis of unknown cause. An isolated small bowel resection with immediate restoration of continuity was first performed to remove the necrotic tissue. The patient developed post-ischemic exudative enteropathy and small intestinal bacterial overgrowth (SIBO). Re-examination of the first computed tomography (CT) scan revealed an isolated dissection of the SMA that had not been diagnosed. The patient was then successfully treated by superior mesenteric revascularization, and after recovering, he underwent small bowel resection for chronic ischemia.

CONCLUSIONS

SMA revascularization has to be performed in case of SMA dissection complicated of bowel ischemia. Enteropathy is a rare complication of chronic mesenteric ischemia requiring digestive and vascular management in a dedicated health-care team.

Surgical Outcomes in Acute Mesenteric Ischemia: Has Anything Changed Over the Years?

BACKGROUND

Despite increases in knowledge and advances in the management of acute mesenteric ischemia syndrome (AMI), there have been no significant improvements in mortality in recent years. The objective of this study was to assess the changes in clinical characteristics and surgical outcomes in patients who underwent AMI over time.

METHODS

A total of 323 consecutive patients who underwent acute mesenteric ischemia at our institution between 1990 and 2015 were examined. The occurrence of significant changes over this 25-year period in demographic data, comorbidity, clinical characteristics, laboratory results, operative findings, etiology of the AMI, and operative mortality were evaluated. The evolution mortality rates for the studied period were analyzed using the additive logistic regression, and the significant effect was determined using the Akaike Information Criterion (AIC).

RESULTS

A significant increasing linear trend was observed in recent years in Charlson score values (p = 0.008), antiplatelet drug intake (p < 0.001), use of CT scan (p < 0.001), arterial thrombosis (p < 0.001), and intestinal resection (p = 0.047), while a decreasing linear trend was observed in digoxin intake (p < 0.001), angiography use (p = 0.004), and embolia (p < 0.001). The rest of the parameters did not present changes over time. Regarding the evolution of the adjusted surgical mortality, a significant decrease according the AIC criterion was observed.

CONCLUSIONS

In recent years, the characteristics of patients with AMI requiring surgery have changed. Changes in operative mortality have also been detected, showing a tendency toward a progressive and significant decrease.

Normal Lactate and Unenhanced CT-Scan Result in Delayed Diagnosis of Acute Mesenteric Ischemia

INTRODUCTION

To investigate the factors associated with a delayed diagnosis (DD) of acute mesenteric ischemia (AMI).

METHODS

An observational cohort study from an intestinal failure center. The primary outcome was DD >24 hours.

RESULTS

Between 2006 and 2015, 74 patients with AMI were included and 39 (53%) had a DD. Plasma lactate <2 mmol/L (odd ratio: 3.2; 95% confidence interval: 1.1-9.1; P = 0.03) and unenhanced computed tomography scan (odds ratio: 5.9; 95% confidence interval: 1.4-25.8; P = 0.01) were independently associated with DD.

DISCUSSION

Suspicion of AMI should no longer be affected by normal plasma lactate levels and should prompt evaluation by a contrast-enhanced computed tomography-scan.

Predictors of irreversible intestinal resection in patients with acute mesenteric venous thrombosis

BACKGROUND

Acute mesenteric venous thrombosis (AMVT) can cause a poor prognosis. Prompt transcatheter thrombolysis (TT) can achieve early mesenteric revascularization. However, irreversible intestinal ischemia still occurs and the mechanism is still unclear.

AIM

To evaluate the clinical outcomes of and to identify predictive factors for irreversible intestinal ischemia requiring surgical resection in AMVT patients treated by TT.

METHODS

The records of consecutive patients with AMVT treated by TT from January 2010 to October 2017 were retrospectively analyzed. We compared patients who required resection of irreversible intestinal ischemia to patients who did not require.

RESULTS

Among 58 patients, prompt TT was carried out 28.5 h after admission. A total of 42 (72.4%) patients underwent arteriovenous combined thrombolysis, and 16 (27.6%) underwent arterial thrombolysis alone. The overall 30-d mortality rate was 8.6%. Irreversible intestinal ischemia was indicated in 32 (55.2%) patients, who had a higher 30-d mortality and a longer in-hospital stay than patients without resection. The significant independent predictors of irreversible intestinal ischemia were Acute Physiology and Chronic Health Evaluation (APACHE) II score (odds ratio = 2.368, 95% confidence interval: 1.047-5.357, P = 0.038) and leukocytosis (odds ratio = 2.058, 95% confidence interval: 1.085-3.903, P = 0.027). Using the receiver operating characteristic curve, the cutoff values of the APACHE II score and leukocytosis for predicting the onset of irreversible intestinal ischemia were calculated to be 8.5 and 12 × 10⁹/L, respectively.

CONCLUSION

Prompt TT could achieve a favorable outcome in AMVT patients. High APACHE II score and leukocytosis can significantly predict the occurrence of irreversible intestinal ischemia. Therefore, close monitoring of these factors may help with the early identification of patients with irreversible intestinal ischemia, in whom ultimately surgical resection is required, before the initiation of TT.

Contrast-Enhanced CT for the Diagnosis of Acute Mesenteric Ischemia

OBJECTIVE. The purpose of this article is to provide an overview of the diagnostic and prognostic roles of CT in the management of acute mesenteric ischemia. CONCLUSION. Acute mesenteric ischemia is defined as inadequate blood supply to the gastrointestinal tract resulting in ischemic and inflammatory injury. The prognosis is poor without treatment. Contrast-enhanced CT has become the cornerstone of diagnosis to identify features of vascular disorders and of intestinal ischemic injury and to visualize bowel necrosis.

Predictive Factors of Intestinal Necrosis in Acute Mesenteric Ischemia

Objectives

Acute mesenteric ischemia (AMI) is a gastrointestinal and vascular emergency in which the detection of patients requiring intestinal resection is mandatory.

Methods

Registered data of 55 consecutive patients admitted to our center between January 2010 and December 2016 that underwent an explorative laparotomy for a suspected diagnosis of irreversible transmural intestinal necrosis (ITIN) were analyzed. Demographic, clinical, laboratory and CT findings were statistically analyzed in order to search predictive factors of ITIN and their correlation to its clinical spectre.

Results

Tobacco use was the most statistically significant (p<0.01) cardiovascular disease risk factor involved in ITIN. Among lab tests, Serum lactate levels ˃ 2mmol/L resulted in a statistically significant association with ITIN (p=0.0001). Organ failure (defined as Marshall score> 2) and the three main CT findings (decreased bowel wall enhancement, bowel loop dilation and demonstrated vessel occlusion) were strongly associated with ITIN (p values: 0.001, 0.007, 0.0013, 0.0005). Only serum lactate levels>2 mmol/L resulted as statistically significant as predictive factors of ITIN in multivariate analysis using logistic regression (OR 49.66 and p-value 0.0021).

Conclusion

Our univariate and multivariate analysis identified multiple factors (Serum lactate levels ˃ 2mmol/L, Organ failure, CT signs) that could suggest patients that require a surgical approach for ITIN.

Superior mesenteric artery endarterectomy for chronic mesenteric ischemia: A viable alternative in poor candidates for endovascular interventions

Background

Chronic mesenteric ischemia can be treated with either endovascular approaches or surgical revascularization. Recent data suggest that surgery leads to more durable symptom relief with similar long-term survival compared to transcatheter angioplasty. Splanchnic vessel endarterectomy has been shown to lead to longer freedom from recurrence compared to the more commonly used surgical bypass procedure.

Methods

We retrospectively reviewed the medical records of patients with chronic mesenteric ischemia who were considered poor candidates for endovascular repair and therefore underwent superior mesenteric artery endarterectomy in our institution. Study period was April 2016 to April 2018.

Results

A 73-year-old female and a 69-year-old male patient fulfilled our inclusion criteria. Extensive stenosis of the celiac axis and the superior mesenteric artery was found in both patients. superior mesenteric artery endarterectomy was performed in both cases. Endarterectomy was closed using a polytetrafluoroethylene patch. Both patients are alive and symptom-free at one year postoperatively with no signs of restenosis.

Conclusions

Our institutional outcomes are in line with recent literature supporting superior mesenteric artery endarterectomy as a viable alternative to surgical bypass in patients with chronic mesenteric ischemia who are suboptimal candidates for endovascular angioplasty and stenting.

Reconstructive Surgery for Intestinal Failure

BACKGROUND

Intestinal failure (IF) in the adult is the result of a wide spectrum of disease. Acute mesenteric ischemia, postoperative short bowel due to a complicative course, and Crohn's disease are major causes of IF. Reconstructive surgery in the context of IF comprises a spectrum of procedures including stoma takedown, reversal of laparostomies, and closure of enteric fistulas.

METHODS

This article is based on a PubMed-based literature search and personal experience in adult patients with IF.

RESULTS

This review summarizes therapeutic options of reconstructive surgery in adult patients focusing on the main reasons of IF such as mesenteric ischemia, complicative previous surgery, and Crohn's disease. Indications and contraindications are discussed as well as the optimal time point of reconstructive surgery.

CONCLUSION

This overview summarizes surgical aspects in a special cohort of patients with a rare disease entity necessitating an interdisciplinary approach.

Outcomes and clinical characteristics of transmural intestinal necrosis in acute mesenteric ischemia

Background: Acute mesenteric ischemia (AMI) is a rare life-threatening condition, especially for the patients with transmural intestinal necrosis (TIN). However, the optimal time for surgical intervention is controversial. As a series study, this study aimed to identify the outcomes and clinical characteristic of patients with TIN. Methods: Clinical data of 158 patients with AMI from January 2010 to December 2017 were retrospectively analyzed in a national gastrointestinal referral center in China to confirm the outcomes and identify predictors for TIN. Results: According to the results of pathological assessment and follow-up, 62 patients were TIN and 96 were non-TIN. Patients with TIN have a higher mortality and incidence of severe complications. The significant independent predictors for TIN were arterial lactate level (OR: 4.76 [2.29 ∼ 9.89]), free intraperitoneal fluid (OR: 9.49 [2.56 ∼ 35.24]) and pneumatosis intestinalis (OR: 7.08 [1.68 ∼ 29.82]) in computed tomography (CT) scan imaging. The overall area under the receiver operating characteristics (ROC) curve of the model was 0.934 (95% confidence interval: 0.893 ∼ 0.974). Using ROC curve, the cutoff value of arterial lactate level predicting the onset of TIN was 2.65 mmol/L. Conclusions: Patients concomitant with TIN manifest a higher risk of poor prognosis. The three predictors for TIN were arterial lactate level >2.65 mmol/L, free intraperitoneal fluid and pneumatosis intestinalis. Close monitoring these predictors would help identify AMI patients developed TIN and in urgent need for bowel resection.

Serological biomarkers for acute mesenteric ischemia

Acute mesenteric ischemia (AMI) defines a complex of conditions characterized by an interruption of the splanchnic circulation, leading to insufficient oxygen delivery or utilization to fill the metabolic needs of the visceral organs. Early diagnosis and immediate therapy are the cornerstones of early ischemia to reach a successful outcome and are necessary to reduce the high mortality. Although there is still lack of specific biomarkers to assist the diagnosis of AMI in clinical practice, there are several biomarkers with high specificity, may become a potential tools in early diagnosis of AMI, including intestinal fatty acid binding protein (I-FABP), a-glutathione S-transferase (a-GST), D-dimer, L- and D-lactate, citrulline, ischemia modified albumin, procalcitonin (PCT). However, they use in clinical limited duo to the many studies about these makers finished with small patient populations, and heterogeneous among these populations. This review describes the etiology of AMI, the current most studied promising biomarkers, the current research situation and future of biomarker research.

Predictive Risk Factors of Intestinal Necrosis in Patients with Mesenteric Venous Thrombosis: Retrospective Study from a Single Center

PURPOSES

Mesenteric venous thrombosis (MVT) is a serious condition. The current study aimed to identify risk factors of intestinal necrosis (IN) in patients with MVT to predict the onset of patients.

METHODS

Data pertaining to patients diagnosed with MVT between 2014 and May 2018 were reviewed. Patients' characteristics and risk factors of IN were assessed.

RESULTS

Seventy-eight patients were included in our study, of whom all cases were diagnosed as superior mesenteric venous thrombosis. There were fifty-eight cases (74%) with intestinal necrosis and twenty cases (26%) without intestinal necrosis. Multivariate analysis of factors associated with IN was organ failure (odds ratio (OR): 4.1; 95% confidence interval (95%CI): 1.26-8.59; P=0.028), elevated serum lactate (OR:3.6; 95% CI: 1.51-5.47; P=0.024), bowel loop dilation on computerized tomography (CT) scan (OR: 2.8; 95% CI: 1.32-7.23; P=0.031), and the time between onset of symptoms and operation (OR: 4.8; 95% CI: 1.36-9.89; P=0.012). Area under the receiver operating characteristics curve for the diagnosis of IN with MVT was 0.901 (95%CI: 0.809-0.993; P=0.000) depending on the different number of predictive factors.

CONCLUSION

Predictive risk factors for IN with MVT were organ failure, elevated serum lactate level, bowel loop dilation on CT, and the time between onset of symptoms and operation. However, this result is from a retrospective study and further long-term, large-sample prospective studies are required to confirm this finding.