Prognostic factors of acute mesenteric ischemia in ICU patients

MCU inhibition protects against intestinal ischemia‒reperfusion by inhibiting Drp1-dependent mitochondrial fission

Intestinal ischemia‒reperfusion (IIR) injury is a common complication of surgery, but clear molecular insights and valuable therapeutic targets are lacking. Mitochondrial calcium overload is an early sign of various diseases and is considered a vital factor in ischemia‒reperfusion injury. The mitochondrial calcium uniporter (MCU), which is located on the inner mitochondrial membrane, is the primary mediator of calcium ion entry into the mitochondria. However, the specific mechanism of MCU in IIR injury remains to be clarified. In this study, we generated an IIR model using C57BL/6 mice and Caco-2 cells and found increases in the calcium levels and MCU expression following IIR injury. The specific inhibition of MCU markedly attenuated IIR injury. Moreover, MCU knockdown alleviates mitochondrial dysfunction by reducing oxidative stress and apoptosis. Mechanistically, MCU knockdown substantially reduced the translocation of Drp1 and thus its binding to Fis1 receptors, resulting in decreased mitochondrial fission. Taken together, our findings demonstrated that MCU is a novel upstream regulator of Drp1 in ischemia‒reperfusion and represents a predictive and therapeutic target for IIR.

Probabilistic Prediction of Gastrointestinal Ischemia after Cardiothoracic Surgery

BACKGROUND

 Gastrointestinal ischemia (GIisch) is challenging to diagnose in patients after cardiothoracic surgery. Computed tomography angiography (CTA) carries substantial false-negative and false-positive rates. The aim of the study was to evaluate if a combination of readily available variables improves the diagnosis of GIisch after cardiothoracic surgery.

METHODS

 This retrospective study included patients receiving intensive care after cardiothoracic surgery. GIisch was confirmed by surgical and/or endoscopic findings. A GIisch prediction score was developed using the Spiegelhalter-Knill-Jones system in a training cohort then tested in a validation cohort (patients without obvious signs of GIisch on CTA).

RESULTS

 The training cohort comprised 125 consecutive patients with suspected GIisch in 2008 to 2019, including 85 with confirmed GIisch. CTA, performed in 92 patients, had a high false-negative rate of 17/60 (28%) and a lower false-positive rate of 7/32 (22%). The score included cardiopulmonary bypass, negatively associated with GIisch, and six variables positively associated with GIisch: intraoperative mean arterial pressure < 50 mm Hg, aspartate aminotransferase > 15 N, lactate increase in 24 hour > 20%, and 3 CTA findings, namely, bowel dilation, bowel wall thickening, and mesenteric vasoconstriction. The area under the receiver operating characteristic was 0.82 (95% confidence interval [CI], 0.51-0.93) in the training cohort and 0.82 (95% CI, 0.68-0.96) in the validation cohort (n = 34 patients). Reliability of the predicted probabilities was greatest for probabilities ≤ 30% or ≥ 70%.

CONCLUSION

 In patients receiving intensive care after cardiothoracic surgery, GIisch cannot be ruled out based solely on CTA findings. A scoring system combining CTA findings with other variables may improve the diagnosis of GIisch in this population.

Mesenteric ischemia in the acute care setting

ABSTRACT

Mesenteric ischemia is a group of disorders requiring prompt identification, supportive care, and treatment. Chronic mesenteric ischemia can develop into acute mesenteric ischemia, which has high mortality. Acute mesenteric ischemia can be occlusive (caused by arterial embolism, arterial thrombosis, or mesenteric venous thrombosis) or nonocclusive, with treatment depending on the underlying cause.

Factors that may affect the outcome of acute occlusive mesenteric ischemia. A single-center study

BACKGROUND

Acute mesenteric ischemia is a rare but lethal disease. Acute occlusive mesenteric ischemia consists of mesenteric artery embolism, mesenteric artery thrombosis, and mesenteric vein thrombosis. This study aimed to investigate the factors that may affect the outcome of acute occlusive mesenteric ischemia.

METHODS

Data from acute occlusive mesenteric ischemia patients admitted between May 2016 and May 2022 were reviewed retrospectively. Patients were divided into 2 groups according to whether complications(Clavien‒Dindo ≥ 2) occurred within 6 months of the first admission. Demographics, symptoms, signs, laboratory results, computed tomography angiography features, management and outcomes were analyzed.

RESULTS

59 patients were enrolled in this study. Complications(Clavien‒Dindo ≥ 2) occurred within 6 months of the first admission in 17 patients. Transmural intestinal necrosis, peritonitis, white blood cell count, percentage of neutrophils, percentage of lymphocytes, neutrophil-to-lymphocyte ratio, lactate dehydrogenase, creatine kinase isoenzyme, cardiac troponin I, laparoscopic exploration rate, open embolectomy rate, enterostomy rate, length of necrotic small bowel, length of healthy small bowel, surgical time and intraoperative blood loss differed significantly between groups. Creatine kinase isoenzyme (OR = 1.415, 95% CI: 1.060-1.888) and surgical time (OR = 1.014, 95% CI: 1.001-1.026) were independent risk factors associated with complications(Clavien‒Dindo ≥ 2).

CONCLUSIONS

Our analysis suggests that acute occlusive mesenteric ischemia patients with a creatine kinase isoenzyme level greater than 2.22 ng/mL or a surgical time longer than 156 min are more likely to experience complications'(Clavien‒Dindo ≥ 2) occurrence within 6 months of the first admission.

Acute mesenteric ischemia: which predictive factors of delayed diagnosis at emergency unit?

PURPOSE

Acute mesenteric ischemia (AMI) is frequently diagnosed late, leading to a poor prognosis. Our aims were to identify predictive factors of delayed diagnosis and to analyze the outcomes of patients with AMI admitted in emergency units.

METHODS

All the patients with AMI (2015-2020), in two Emergency units, were retrospectively included. Two groups were defined according to the time of diagnosis between the arrival at emergency unit and the CT scan: ≤ 6 h (early), > 6 h (delayed).

RESULTS

119 patients (mean age = 71 ± 7 years) were included. The patients with a delayed diagnosis (n = 33, 28%) were significantly associated with atypical presentation, including lower rates of abdominal pain (73 vs 89%, p = 0.003), abdominal tenderness (33 vs 43%, p = 0.03), and plasma lactate (4 ± 2 vs 6 ± 7 mmol/l, p = 0.03) when compared with early diagnosis. After multivariate analysis, the absence of abdominal pain was the only independent predictive factor of delayed diagnosis (Odd Ratio = 0.17; 95% CI = 0.03-0.88, p = 0.03). Patients with delayed diagnosis tended to be associated to lower rates of revascularization (9 vs 17%, p = 0.4), higher rates of major surgical morbidity (90 vs 57%, p = 0.1), longer length of stay (16 ± 23 vs 13 ± 15 days, p = 0.4) and, at the end of follow-up, higher rate of short small bowel syndrome (18 vs 7%, p = 0.095).

CONCLUSION

AMI is a challenge for emergency physicians. History of patient, physical exam, biological data are not sufficient to diagnose AMI. New biomarkers, and awareness of emergency physicians should improve and accelerate the diagnosis of AMI.

Network pharmacology analysis combined with experimental validation to explore the therapeutic mechanism of salidroside on intestine ischemia reperfusion

ETHNOPHARMACOLOGICAL RELEVANCE

Salidroside (SAL), a phenolic natural product present in Rhodiola rosea, are commonly used in the treatment of various ischemic-hypoxic diseases, including intestinal ischemia-reperfusion (IR) injury. However, their efficacy and potential mechanisms in the treatment of intestinal IR injury have not been investigated.

OBJECTIVE

The objective of the present study is to investigate the pharmacological mechanism of action of SAL on intestinal IR injury using a network pharmacology approach combined with experimental validation.

METHODS

In the present study, we used the Traditional Chinese Medicine Systematic Pharmacology (TCMSP) database and analysis platform and Comparative Toxicogenomics Database (CTD) to predict possible target genes of SAL, collected relevant target genes of intestinal IR injury from GeneCards and DisGenet websites, and collected summary data to screen common target genes. Then, the protein-protein interaction (PPI) target network was constructed and analyzed by STRING database and Cytoscape 3.8.2 with the above intersecting genes. Then, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed and the component-target-pathway network was constructed, followed by the use of molecular docking and molecular dynamic simulation to verify the possible binding conformation between SAL and candidate targets to further explore the potential targets of SAL in the treatment of intestinal IR injury. Finally, an in vivo model of mouse superior mesenteric artery ligation was established to assess the anti-intestinal IR injury effect of SAL by assessing histopathological changes in mouse small intestine by HE staining, detecting inflammatory factor expression by ELISA kit, and detecting the expression of key protein targets by Western blotting.

RESULTS

A total of 166 SAL target genes and 1740 disease-related targets were retrieved, and 88 overlapping proteins were obtained as potential therapeutic targets. The pathway enrichment analysis revealed that the pharmacological effects of SAL on intestinal IR injury were anti-hypoxic, anti-inflammatory and metabolic pathway related, and the molecular docking and molecular dynamic simulation results showed that the core bioactive components had good binding affinity for TXNIP and AMPK, and the immunoblotting results indicated that the expression levels of TXNIP and AMPK in the small intestinal tissues of mice in the drug-treated group compared with the model group were significantly changed.

CONCLUSION

SAL may target AMPK and TXNIP domains to act as a therapeutic agent for intestinal IR. These findings comprehensively reveal the potential therapeutic targets for SAL against intestinal IR and provide theoretical basis for the clinical application of SAL in the treatment of intestinal IR.

Mesenteric ischemia in the acute care setting

ABSTRACT

Mesenteric ischemia is a group of disorders requiring prompt identification, supportive care, and treatment. Chronic mesenteric ischemia can develop into acute mesenteric ischemia, which has high mortality. Acute mesenteric ischemia can be occlusive (caused by arterial embolism, arterial thrombosis, or mesenteric venous thrombosis) or nonocclusive, with treatment depending on the underlying cause.

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.

Discrimination between normal and necrotic small intestinal tissue using hyperspectral imaging and unsupervised classification

Objective and automatic clinical discrimination of normal and necrotic sites of small intestinal tissue remains challenging. In this study, hyperspectral imaging (HSI) and unsupervised classification techniques were used to distinguish normal and necrotic sites of small intestinal tissues. Small intestinal tissue hyperspectral images of eight Japanese large-eared white rabbits were acquired using a visible near-infrared hyperspectral camera, and K-means and density peaks (DP) clustering algorithms were used to differentiate between normal and necrotic tissue. The three cases in this study showed that the average clustering purity of the DP clustering algorithm reached 92.07% when the two band combinations of 500-622 and 700-858 nm were selected. The results of this study suggest that HSI and DP clustering can assist physicians in distinguishing between normal and necrotic sites in the small intestine in vivo.

High risk and low prevalence diseases: Mesenteric ischemia

INTRODUCTION

Mesenteric ischemia is a rare, frequently misdiagnosed, serious condition that carries with it a high rate of morbidity and mortality.

OBJECTIVE

This review highlights the pearls and pitfalls of mesenteric ischemia, including presentation, diagnosis, and management in the emergency department (ED) based on current evidence.

DISCUSSION

Mesenteric ischemia is an abdominal vascular emergency that includes superior mesenteric arterial embolism, arterial thrombosis, venous mesenteric ischemia, and non-occlusive mesenteric ischemia. It is associated with a variety of risk factors including older age, cardiovascular disease, hypercoagulable state, and end-stage renal disease. The presentation depends on the underlying pathophysiology. While arterial embolic disease may present with sudden, severe pain, the early stages of the disease and other forms can present with vague symptoms, including generalized abdominal pain, weight loss, vomiting, and diarrhea. Laboratory testing can suggest the disease with leukocytosis and elevated lactate, but normal values should not be used to exclude the diagnosis. The imaging modality of choice is triple phase computed tomography with non-contrast, arterial, and delayed phases. The initial ED management includes fluid resuscitation, symptomatic therapy, broad-spectrum antibiotics, and anticoagulation. Emergent consultation with a multidisciplinary team including diagnostic and interventional radiologists and cardiovascular and general surgeons is necessary for definitive treatment.

CONCLUSIONS

An understanding of mesenteric ischemia can assist emergency clinicians in diagnosing and managing this disease.

Are the conventional scoring systems efficient in predicting mortality of acute mesenteric ischemia?: Mortality estimation in patients with AMI

Acute mesenteric ischemia is a surgical emergency with high morbidity and mortality rates. Therefore, it is important to determine the prognosis for this disease. In the present study, we aimed to compare the prediction accuracy of 3 scoring systems: Acute physiology and chronic health evaluation II, sequential organ failure assessment score and simplified acute physiology score II (SAPS II). The retrospective cohort study was conducted in a university hospital. Eighty-two acute mesenteric ischemia patients were evaluated retrospectively. The mortality prediction abilities of the scoring systems were evaluated by comparing the prediction rates of > 10%, 30% and 50% and the actual mortality among survivors and non-survivors in pairs. Predicted mortality rates among survivors and non-survivors differed among the 3 classification systems. The mortality estimates of the SAPS II were closer to the actual mortality rates. Analysis of the estimated mortality rates as mortality risk limits showed that acute physiology and chronic health evaluation II was superior to sequential organ failure assessment score and SAPS II in estimating mortality rates, whereas SAPS II was more successful in detecting survivors. The estimated mortality rates of the 3 rating systems, the estimated mortality rates were higher in the non-survivor group than in the survivor group. The accuracy of the SAPS II in determining prognosis was relatively better.

Treatment of Acute Mesenteric Ischemia: Individual Challenges for Interventional Radiologists and Abdominal Surgeons

Background: Acute mesenteric ischemia (AMI) is a life-threatening condition resulting from occlusion of the mesenteric arterial vessels. AMI requires immediate treatment with revascularization of the occluded vessels. Purpose: to evaluate the technical success, clinical outcomes and survival of patients receiving endovascular treatment for AMI followed by surgery. Material and Methods: A search of our institution’s database for AMI revealed 149 potential patients between 08/2016 and 08/2021, of which 91 were excluded due to incomplete clinical data, insufficient imaging or missing follow-up laparoscopy. The final cohort included 58 consecutive patients [(median age 73.5 years [range: 43−96 years], 55% female), median BMI 26.2 kg/m2 (range:16.0−39.2 kg/m2)]. Periinterventional imaging regarding the cause of AMI (acute-embolic or acute-on-chronic) was evaluated by two radiologists in consensus. The extent of AMI and the degree of technical success was graded according to a modified TICI (Thrombolysis in Cerebral Infarction scale) score (TICI-AMI) classification (0: no perfusion; 1: minimal; 2a < 50% filling; 2b > 50%; 2c: near complete or slow; 3: complete). Lab data and clinical data were collected, including the results of follow-up laparoscopy. Non-parametric statistics were used. Results: All interventions were considered technically successful. The most common causes of AMI were emboli (51.7%) and acute-on-chronic thrombotic occlusions (37.9%). Initial imaging showed a TICI-AMI score of 0, 1 or 2a in 87.9% (n = 51) of patients. Post-therapeutic TICI-AMI scores improved significantly with 87.9% of patients grade 2b and better. Median lactate levels reduced from 2.7 (IQR 2.0−3.7) mg/dL (1−18) to 1.45 (IQR 0.99−1.90). Intestinal ischemia was documented in 79.1% of cases with resection of the infarcted intestinal loops. In total, 22/58 (37.9%) patients died during the first 30 days after intervention and surgery. According to CIRSE criteria, we did not observe any SAE scores of grade 2 or higher. Conclusions: AMI is a serious disease with high lethality within the first 30 days despite optimal treatment. However, interventional revascularization before surgery with resection of the infarcted bowel can save two out of three of critically ill patients.

Basic demographic characteristics and prevalence of comorbidities in acute mesenteric ischemia: a systematic review and proportional meta-analysis

PURPOSE

The aim of this systematic review and meta-analysis was to examine and assess the basic demographic characteristics and prevalence of comorbidities in acute mesenteric ischemia (AMI) and its various subtypes.

PATIENTS AND METHODS

A literature search was conducted by using the databases PubMed, EMBASE, and Google Scholar (to June 1, 2022). Random-effects or fixed-effects models were selected to pool means and proportions and their corresponding 95% confidence intervals (CI), based on heterogeneity between studies. The results of meta-analyses for basic demographic characteristics and prevalence (proportions) of each specific comorbidities of acute mesenteric ischemia (AMI) and its various subtypes were described.

RESULTS

Ninety-nine studies were included in the meta-analysis, including 17,103 patients with AMI. Furthermore, 7941 patients with subclass diagnoses of AMI were identified, including 3,239 patients with arterial occlusive mesenteric ischemia (AOMI), 2,977 patients with nonocclusive mesenteric ischemia (NOMI), and 1,725 patients with mesenteric venous thrombosis (MVT). As a surgical emergency, AMI is associated with older patients and a high likelihood of multisystem comorbidities. Comorbidities of AMI involved multiple systemic diseases, including cardiovascular disease, endocrine and metabolic diseases, kidney diseases, digestive diseases, respiratory diseases, cerebrovascular diseases, vascular diseases, and cancer.

CONCLUSION

The basic demographic characteristics and the prevalence of comorbidities of different subtypes of AMI are different. The management of comorbidities should be an essential part of improving the prognosis of AMI patients and may contribute to precise prevention of AMI.

Mortality Prediction Model before Surgery for Acute Mesenteric Infarction: A Population-Based Study

Surgery for acute mesenteric infarction (AMI) is associated with high mortality. This study aimed to generate a mortality prediction model to predict the 30-day mortality of surgery for AMI. We included patients ≥18 years who received bowel resection in treating AMI and randomly divided into the derivation and validation groups. After multivariable analysis, the ‘Surgery for acute mesenteric infarction mortality score’ (SAMIMS) system was generated and was including age >62-year-old (3 points), hemodialysis (2 points), congestive heart failure (1 point), peptic ulcer disease (1 point), diabetes (1 point), cerebrovascular disease (1 point), and severe liver disease (4 points). The 30-day-mortality rates in the derivation group were 4.4%, 13.4%, 24.5%, and 32.5% among very low (0 point), low (1−3 point(s)), intermediate (4−6 points), and high (7−13 points)-risk patients. Compared to the very-low-risk group, the low-risk (OR = 3.332), intermediate-risk (OR = 7.004), and high-risk groups (OR = 10.410, p < 0.001) exhibited higher odds of 30-day mortality. We identified similar results in the validation group. The areas under the ROC curve were 0.677 and 0.696 in the derivation and validation groups. Our prediction model, SAMIMS, allowed for the stratification of the patients’ 30-day-mortality risk of surgery for acute mesenteric infarction.

Acute mesenteric ischemia due to percutaneous coronary intervention: A case report

BACKGROUND

Percutaneous coronary intervention (PCI) is extensively used to treat acute coronary syndromes (ACS). Acute mesenteric ischemia is a life-threatening disease if untreated.

CASE SUMMARY

An 81-year-old female presented with 3 d of lethargy and 1 d of dyspnea. On November 16, 2021, the patient developed a coma. Her oxygen saturation dropped to 70%-80%, the patient was admitted to the intensive care unit for further treatment. Chest computed tomography (CT) showed chronic bronchitis, emphysema, and multiple lung infections. Abdominal CT scan showed no obvious abnormalities, but have severely calcified abdominal vessels. The patient received assisted ventilation, and vasoactive, and anti-infection drugs. Troponin level was elevated. Since the patient was in a coma, it could not be determined whether she had chest pain. The cardiologist assumed that the patient had developed ACS; therefore, the patient underwent PCI via the left femoral artery approach, and no obvious abnormalities were found in the left and right coronary arteries. On the second postoperative day, the patient presented with abdominal distension and decreased bowel sounds; constipation was considered and a glycerin enema was administered. On day 4, the patient suddenly lost consciousness, and had decreased blood pressure, abdominal wall swelling with increased tension, and absence of bowel sounds. An urgent abdominal CT scan revealed gas in her hepatic portal system with extensive bowel wall necrosis. The patient died on day 5 due to intractable shock.

CONCLUSION

The potential serious complications in patients undergoing PCI, especially the patients who are hemodynamically unstable and have severely calcified abdominal vessels, should all be considered.

Predicting outcomes of mesenteric ischemia postcardiac surgery: A systematic review

OBJECTIVE

This systematic review aims to identify predictors of outcomes of mesenteric ischemia in patients following cardiac surgery.

METHODS

A comprehensive literature search was done on EMBASE, PubMed, Ovid MEDLINE, and SCOPUS using keywords relating to bowel ischemia and cardiac surgery. Database search results were screened by at least two authors and 32 articles were selected for inclusion in this review.

RESULTS

Data on 1907 patients were analyzed. The mean age was 70.0 ± 2.99 years and the prevalence of bowel ischemia was 1.74%. Advanced age was a significant risk factor. 63.16% of patients reported were men, and 58.4% of patients died in hospital. There was heterogeneity in the reported significance of the following preoperative risk factors: hypertension, smoking status, type 2 diabetes mellitus, end-stage renal disease, preoperative left ventricular ejection fraction <35%. Cardiopulmonary bypass (CPB) time, preoperative/operative intra-aortic balloon pump (IABP) support, and inotrope usage were significantly associated with the development of mesenteric ischemia; however, other intraoperative factors including the type of cardiac surgery and duration of aortic cross-clamping had varying levels of reported significance. There were discrepancies in the reported significance of leukocytosis and metabolic acidosis (pH <7.3) as postoperative markers. Postoperative vasopressor use, prolonged ventilation time, and elevation in lactate, transaminases, creatinine, and intestinal fatty acid-binding protein (IFABP) levels were found to be strongly associated with bowel ischemia.

CONCLUSION

This systematic review found the strongest associations of mesenteric ischemia postcardiac surgery to be advanced age, CPB time, rise in lactate, transaminases, creatinine, and IFABP. IABP support, vasopressor, and inotrope use as well as prolonged ventilation were strongly linked too.

l-lactate kinetics after abdominal aortic surgery and intestinal ischemia - An observational cohort study

BACKGROUND

Postoperative intestinal ischemia is a severe complication in abdominal aortic surgery. Early diagnosis is needed for adequate and timely treatment. We studied the postoperative kinetics of l-lactate in vascular patients to assess its value as a marker for early postoperative intestinal ischemia detection.

MATERIAL AND METHODS

We performed a prospective non-randomized single-center observational cohort study in eighty elective patients, fifty operated on for abdominal aortic aneurysm (AAA) and thirty for aortoiliac occlusive disease (AIOD). Serum l-lactate was measured preoperatively, intraoperatively, and postoperatively at defined timepoints up to postoperative day 7. Intestinal ischemia was detected using MRI enterocolography. We have used univariate logistic regression and receiver operating characteristics curves for the evaluation of marker accuracy.

RESULTS

We recorded 6 cases of postoperative intestinal ischemia (7.5%), five non-transmural and one transmural. Two patients died because of this complication (mortality 33%). The comparison of AAA and AIOD cohorts showed a significant difference in l-lactate levels at one intraoperative timepoint, which was attributable to procedure differences. The only preoperative factor associated with higher l-lactate levels at some timepoints was chronic kidney disease. Patients suffering postoperative intestinal ischemia had elevated serum l-lactate levels at multiple timepoints. The most accurate timepoint for diagnosis was 24 h after the declamping of the vascular reconstruction (DC24H), the second was 10 min after declamping. Sensitivity, specificity, positive and negative predictive values at timepoint DC24H were 100%, 82%, 32%, and 100%, respectively.

CONCLUSION

Serum l-lactate levels might help in the early detection of postoperative intestinal ischemia after aortic surgery if proper timepoints are used. Cutoff values need to be established in large-scale prospective studies.

Ischemic bowel disease in 2021

Ischemic bowel disease (ISBODI) includes colon ischemia, acute mesenteric ischemia (AMI) and chronic mesenteric ischemia (CMI). Epidemiologically, colon ischemia is the most common type followed by AMI and CMI. There are various risk factors for the development of ISBODI. Abdominal pain is the common presenting symptom of each type. High clinical suspicion is essential in ordering appropriate tests. Imaging studies and colonoscopy with biopsy are the main diagnostic tests. Treatment varies from conservative measures to surgical resection and revascularization. Involvement of multidisciplinary team is essential in managing ISBODI. Although open surgery with revascularization plays an important role, recently there is an increasing interest in percutaneous endovascular treatment.

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.

The effect of comorbidity on early clinical decision making in acute mesenteric ischemia

INTRODUCTION

Acute mesenteric ischemia (AMI) is a surgical emergency with a high mortality and morbidity rate. Prompt diagnosis and early surgical management are the cornerstones of management. In certain patients, however, treatment is futile and early palliative care, lessens patient, and family distress. The aim of this study was to investigate factors, focusing on patient comorbidity, that may predict futility of treatment and hence, guide clinicians in their decision making.

PATIENTS AND METHODS

Consecutive adult patients with AMI diagnosed on imaging were reviewed for demographics, comorbidity, imaging, and biochemical results.

RESULTS

Seventy patients were identified with average age of 67 (range 33 - 94). Overall hospital mortality was 72%. Patients were divided into three distinct groups, patients who recovered (27%), patients deceased despite surgical treatment (18%), and patients palliated on presentation (54%). Age was comparable between groups (61 vs. 69 vs. 69; p=.2). Length of stay was highest in the recovered group (41.6 vs. 12.3 vs. 2.8 d). Biochemically, only lactate level differed (3.1 vs. 2.3 vs. 5.3 mmol/L, p=.03). Both deceased and palliative group scored similarly but significantly higher than the recovered group in both the Charlson comorbidity index (CCI) (4.2 and 5.6 vs. 3.4, p=.02) and age-adjusted CCI (ACCI) (6.7 and 8.2 vs. 5; p<.01). Other co-morbidities of atrial fibrillation (AF) and hypertension were comparable.

CONCLUSIONS

Raised ACCI confers poor outcomes in AMI despite surgical management. ACCI may be used to aid early decision making in AMI, predicting futility of treatment, and altering management goals to palliative comfort care.

Prospects of Intraoperative Multimodal OCT Application in Patients with Acute Mesenteric Ischemia

INTRODUCTION

Despite the introduction of increasingly multifaceted diagnostic techniques and the general advances in emergency abdominal and vascular surgery, the outcome of treatment of patients with acute impaired intestinal circulation remains unsatisfactory. The non-invasive and high-resolution technique of optical coherence tomography (OCT) can be used intraoperatively to assess intestine viability and associated conditions that frequently emerge under conditions of impaired blood circulation. This study aims to demonstrate the effectiveness of multimodal (MM) OCT for intraoperative diagnostics of both the microstructure (cross-polarization OCT mode) and microcirculation (OCT angiography mode) of the small intestine wall in patients with acute mesenteric ischemia (AMI).

METHODS AND PARTICIPANTS

A total of 18 patients were enrolled in the study. Nine of them suffered from AMI in segments II-III of the superior mesenteric artery (AMI group), whereby the ischemic segments of the intestine were examined. Nine others were operated on for adenocarcinoma of the colon (control group), thus allowing areas of their normal small intestine to be examined for comparison. Data on the microstructure and microcirculation in the walls of the small intestine were obtained intraoperatively from the side of the serous membrane using the MM OCT system (IAP RAS, Russia) before bowel resection. The MM OCT data were compared with the results of histological examination.

RESULTS

The study finds that MM OCT visualized the damage to serosa, muscularis externa, and blood vessels localized in these layers in 100% of AMI cases. It also visualized the submucosa in 33.3% of AMI cases. The MM OCT images of non-ischemic (control group), viable ischemic, and necrotic small intestines (AMI group) differed significantly across stratification of the distinguishable layers, the severity of intermuscular fluid accumulations, and the type and density of the vasculature.

CONCLUSION

The MM OCT diagnostic procedure optimally meets the requirements of emergency surgery. Data on the microstructure and microcirculation of the intestinal wall can be obtained simultaneously in real time without requiring contrast agent injections. The depth of visualization of the intestinal wall from the side of the serous membrane is sufficient to assess the volume of the affected tissues. However, the methodology for obtaining MM OCT data needs to be improved to minimize the motion artefacts generated in actual clinical conditions.

Endovascular Revascularization with Stent Implantation in Patients with Acute Mesenteric Ischemia due to Acute Arterial Thrombosis: Clinical Outcome and Predictive Factors

Purpose

To determine 30-day-mortality rates and identify predictors for survival in patients undergoing endovascular revascularization for acute mesenteric ischemia (AMI) due to occlusion of the celiac (CA) or superior mesenteric artery (SMA) from arterial thrombosis in the setting of atherosclerosis at the vessel origin.

Materials and Methods

A retrospective analysis on patients who underwent acute endovascular revascularization to treat AMI caused by thrombotic occlusion of the CA and/or SMA between January 2011 and December 2019 was conducted. 30-day-mortality rates were calculated. Univariate binomial logistic regression analyses (p < 0.05) were performed to assess whether the following factors were associated with 30-day mortality: sex, age, history of smoking, history of abdominal angina, signs of bowel necrosis on pre-interventional CT, one- vs. two-vessel disease, patency of the inferior mesenteric artery, outpatient or inpatient occurrence of ischemia, onset of AMI during ITU stay, elevated pre-interventional serum lactate levels, total leukocyte count, platelet/lymphocyte ratio and neutrophil/lymphocyte ratio.

Results

40 patients were included in this analysis. 30-day-mortality rate was 25/40 (62.5%). Median overall survival of patients who survived the first 30 days was 36 ± 18 months. None of the analyzed factors was statistically significantly associated with 30-day mortality.

Conclusion

Although mortality of patients with AMI due to acute arterial thrombosis remains high, almost 40% of patient who underwent emergent endovascular revascularization survived longer than one month. Since no predictors for the outcome in these patients were identified, all patients with AMI should be offered an immediate revascularization effort.

Vascular Calcifications are Associated with Increased Mortality in Patients with Acute Mesenteric Ischemia

BACKGROUND

Vascular calcifications have been identified as predictors of mortality in several cardiovascular diseases but have not been investigated in context of acute mesenteric ischemia. The aim of this study was to investigate the impact of vascular calcifications in patients with acute mesenteric ischemia.

METHODS

Patients admitted for an acute mesenteric ischemia were retrospectively included. The presence of calcifications in the visceral aorta, the celiac trunk, the superior mesenteric artery, and the renal arteries was assessed on computed tomography scan images at the arterial phase. The calcification volumes were measured using the software Aquarius iNtuition Edition®.

RESULTS

The all-cause mortality was 55 out of 86 patients (63.9%) for a median follow-up of 3.5 days (1-243). The survival rate of patients with calcification in the superior mesenteric artery was significantly lower than that of those without calcification (22% vs. 55.6%, P = 0.019). Patients who died had significantly a higher frequency of calcifications in the superior mesenteric artery, the visceral aorta, the celiac trunk, and the renal arteries.

CONCLUSIONS

The presence of vascular calcifications in the superior mesenteric artery is associated with increased mortality in patients diagnosed with acute mesenteric ischemia. Further studies are required to identify the mechanisms underlying this association.

Inhibition of a triggering receptor expressed on myeloid cells-1 (TREM-1) with an extracellular cold-inducible RNA-binding protein (eCIRP)-derived peptide protects mice from intestinal ischemia-reperfusion injury

BACKGROUND

Intestinal ischemia-reperfusion injury results in morbidity and mortality from both local injury and systemic inflammation and acute lung injury. Extracellular cold-inducible RNA-binding protein is a damage associated molecular pattern that fuels systemic inflammation and potentiates acute lung injury. We recently discovered a triggering receptor expressed on myeloid cells-1 serves as a novel receptor for extracellular cold-inducible RNA-binding protein. We developed a 7-aa peptide, named M3, derived from the cold-inducible RNA-binding protein, which interferes with cold-inducible RNA-binding protein's binding to a triggering receptor expressed on myeloid cells-1. Here, we hypothesized that M3 protects mice against intestinal ischemia-reperfusion injury.

METHODS

Intestinal ischemia was induced in C57BL/6 mice via clamping of the superior mesenteric artery for 60 minutes. At reperfusion, mice were treated intraperitoneally with M3 (10 mg/kg body weight) or normal saline vehicle. Mice were killed 4 hours after reperfusion and blood and lungs were collected for various analysis. A 24-hours survival after intestinal ischemia-reperfusion was assessed.

RESULTS

Serum levels of organ injury markers aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and lactate were increased with intestinal ischemia-reperfusion, while treatment with M3 significantly decreased their levels. Serum, intestinal, and lung levels of proinflammatory cytokines and chemokines were also increased by intestinal ischemia-reperfusion, and treatment with M3 significantly reduced these values. Intestinal ischemia-reperfusion caused significant histological intestinal and lung injuries, which were mitigated by M3. Treatment with M3 improved the survival from 40% to 80% after intestinal ischemia-reperfusion.

CONCLUSION

Inhibition of triggering receptor expressed on myeloid cells-1 by an extracellular cold-inducible RNA-binding protein-derived small peptide (M3) decreased inflammation, reduced lung injury, and improved survival in intestinal ischemia-reperfusion injury. Thus, blocking the extracellular cold-inducible RNA-binding protein-triggering receptor expressed on myeloid cells-1 interaction is a promising therapeutic avenue for mitigating intestinal ischemia-reperfusion injury.

Review Article: Mesenteric Ischemia

PURPOSE OF REVIEW

Mesenteric ischemia (MI), both acute (AMI) and chronic (CMI), is a challenging diagnosis to make, and early diagnosis and treatment are vital to improve outcomes. This manuscript summarizes the most up to date information on diagnosis and treatment of these disorders.

RECENT FINDINGS

There have been several significant advancements in the computed tomography (CT) diagnostic imaging as well as medical and endovascular management of AMI and CMI. In appropriate populations, endovascular interventions appear superior to open surgical management with lower mortality, morbidity, and cost of care. Efficient clinical identification and targeted testing are essential to diagnose AMI and CMI. Aggressive resuscitation and early endovascular (or in select cases, surgical) intervention improve outcomes in those with AMI. In those with CMI, considering this on the differential diagnosis and imaging appropriately can identify those that might benefit from intervention and halt progression to acute episodes.

Terlipressin relieves intestinal and renal injuries induced by acute mesenteric ischemia via PI3K/Akt pathway

Background: To date, the effect of vasopressin on organ damages after acute mesenteric ischemia (MI) remains poorly understood. Aims: To investigate the effect of terlipressin, a selective vasopressin V1 receptor agonist, versus norepinephrine on the intestinal and renal injuries after acute MI, and to explore the underlying mechanism of terlipressin. Methods: Acute MI model was produced by clamping the superior mesenteric artery for 1 hour. Immediately after unclamping, terlipressin or norepinephrine was intravenously administered for 2 hours. Meanwhile, in vitro, RAW264.7 cells were treated with lipopolysaccharide or lipopolysaccharide+terlipressin. In addition, wortmannin was used to determine the role of phosphoinositide 3-kinase (PI3K)/ protein kinase B (Akt) pathway in the potential impacts of terlipressin. Results: MI led to severe hypotension, caused notable intestinal and renal impairments and resulted in high mortality, which were markedly improved by terlipressin or norepinephrine. Terlipressin increased mean arterial pressure, decreased intestinal epithelial cell apoptosis, inhibited the generation of M1 macrophage in intestinal and renal tissues, and hindered the release of inflammatory cytokines after MI. Moreover, in cultured macrophages, terlipressin reduced the mRNA level of specific M1 markers and the release of inflammatory cytokines caused by lipopolysaccharide challenge. Wortmannin decreased the expression of PI3K and Akt induced by terlipressin in cells and in tissues, and abolished the above protective effects conferred by terlipressin. Conclusions: Terlipressin or norepinephrine could effectively improve organ damages and mortality after acute MI. Terlipressin elevates blood pressure and inhibits intestinal epithelial apoptosis and macrophage M1 polarization via the PI3K/Akt pathway.

Acute mesenteric ischemia (AMI): absence of renal insufficiency and performance of early bowel resection may indicate improved outcomes

PURPOSE

Acute mesenteric ischemia (AMI) is still associated with very high morbidity and mortality while the rareness and heterogeneity hamper the establishment of evidence-based guidelines. We sought to help standardize contemporary treatment by a cohort study at our tertiary center in the rising endovascular age.

METHODS

A retrospective cohort study was conducted from 2005 to 2015. Patients with occlusive (OMI), non-occlusive (NOMI), and venous mesenteric ischemia (VMI) were compared with respect to clinical and treatment parameters as well as outcome.

RESULTS

The study cohort consisted of 48 patients composed of 27 males and 21 females with an average age of 63 years and an average BMI of 25.1 kg/m². In 48% of patients (N=23), an acute arterial OMI had occurred while NOMI was present in 31% (N=15) and VMI in 21% (N=10). Interventional and intraoperative recanalizations were significantly more often required in OMI patients compared with other entities (p=0.003). Patients with venous mesenteric ischemia had a significant better overall survival than patients with OMI or NOMI in the univariate analysis (p=0.027). Patients with renal failure had a 14.7-fold higher relative risk (Cox p=0.013) and patients without bowel resection during primary surgery had a 17.8-fold higher relative risk (Cox p=0.047) to die of AMI in the postoperative course.

CONCLUSIONS

AMI remains a rare but oftentimes fatal disease. Our study provides evidence that outcome may depend on the AMI subtype, presence of renal insufficiency, and early bowel resection. Further research should help individualize treatment for optimized outcomes.