Acute mesenteric ischemia: diagnostic approach and surgical treatment

Retrograde open mesenteric stenting and outcomes for acute mesenteric ischemia

OBJECTIVES

Data regarding retrograde open mesenteric stenting (ROMS) for urgent mesenteric ischemia is limited to small single center and case series, with variable utilization across patient populations and ill-defined outcomes. We aimed to evaluate characteristics and outcomes of patients with acute mesenteric ischemia requiring urgent surgical intervention.

METHODS

Retrospective cohort study of patients with mesenteric ischemia requiring urgent surgical intervention from 2018 to 2020 was queried from the National Inpatient Sample (NIS) database. Study groups were defined as those requiring an open bypass (BYPASS), an open superior mesenteric artery embolectomy (OPEN), or ROMS. Descriptive statistics were used to report variables. Comparisons were mad using t test, chi-squares tests, and multivariate regression reported as odds ratio (OR), 95% confidence interval (CI) where appropriate.

RESULTS

898 patients with mesenteric ischemia requiring urgent surgical intervention were included: Bypass: 284, OPEN: 363, ROMS: 251. There was no difference in gender or race between groups. Patients requiring ROMS were more likely to be older 70.2 + 11.3versus Bypass 66.81 + 11.6 and OPEN 67.17 + 14.5, p = 0.0035. ROMS patients had the highest Charlson Comorbidity Index (CCI) 2.9 versus 2.5 Bypass and 2.6 OPEN, p = 0.0292 with the most frequent comorbidities: Diabetes 37% (p = 0.01), renal disease 24.3% (p = 0.5), and previous preoperative myocardial infarction 9.2%, p = 0.05; however, the lowest mortality rate was seen within this Group 15.9% versus bypass 19.7%, OPEN 34.5%, p < 0.0001. Patients requiring bypass were more likely to have chronic pulmonary disease 34.5% versus OPEN 24.2% and ROMS 31.5%, p = 0.013, peripheral vascular disease (PVD) 38% versus OPEN 16%, and ROMS 29.9%, p < 0.0001. On multivariate regression, ROMS was associated with 50% decreased incidence of mortality (OR 0.45, 95% CI 0.27-0.75). Open SMA embolectomy was associated with nearly 2x mortality rate compared to bypass procedures OR 2.0, 95% CI 1.3-3.0, p < 0.001. Previous MI was also associated with nearly 2x incidence of mortality (OR 1.9, 95% CI 1.01-3.6), while pre-existing PVD conferred a protective effect (OR 0.56, 95% CI 0.36-0.89). Higher CCI and age were associated with slightly increased risk for mortality OR 1.2 and 1.03, p < 0.05 for both.

CONCLUSIONS

In patients with acute mesenteric ischemia, ROMS demonstrated a significant mortality benefit compared to traditional open procedures. Advanced age, history of MI, and open SMA embolectomy were associated with increased mortality. Little data exists regarding ROMS in a real-world population evaluating ROMS, which is a newer technique. These data suggest that ROMS may be a superior alternative to restore mesenteric flow in the acute setting and further prospective studies evaluating ROMS to other procedural types in urgent and elective settings are needed.

Is there a faster and easier method for assessing the severity of acute mesenteric ischemia?

Acute mesenteric ischemia (AMI) is a potentially fatal abdominal emergency. The estimation of the severity of AMI is of great importance since changes in disease severity may have different impacts on the treatment options. This study aims to define laboratory and radiological parameters that can successfully predict the severity of AMI. Data from 100 patients who were treated conservatively and underwent an operation with a diagnosis of AMI between the years 2010 and 2019 were reviewed. The patients were divided into 3 groups as those treated with a conservative approach (group 1), those with partial intestinal ischemia (group 2), and those with complete intestinal ischemia (group 3) according to the pathology results. Laboratory findings of the patients were recorded and matched with radiological findings. The white blood cell (WBC) count, neutrophil (NEUT) count, neutrophil/lymphocyte ratio, and C-reactive protein/albumin ratios were the considered distinctive parameters for distinguishing the third group from the first group. However, the same result cannot be applied to the first and the second groups since only the WBC and NEUT counts showed distinctive performance. The measurement of neutrophil/lymphocyte ratio, WBC, NEUT, and albumin levels can be used to predict the severity of AMI. We believe that evaluating these laboratory parameters will greatly prevent possible morbidity and mortality in the patient. Also, we were able to observe that the parameters used in predicting AMI severity can be verified with rapid and low-cost radiological imaging techniques.

A 52-Year-Old Woman with Abdominal Pain and Vomiting

A 52-Year-Old Woman with Abdominal Pain and VomitingA 52-year-old woman presented for evaluation of abdominal pain, nausea, and vomiting after consuming a large calzone. How do you approach the evaluation, and what is the diagnosis?

Acute Mesenteric Ischemia: The Diagnostic Value of QT Parameters and their Relationship with CT Findings

BACKGROUND

One of the greatest challenges in the diagnosis of acute mesenteric ischemia (AMI) is the lack of specific laboratory tests that support multidetector computed tomography (CT). Our aim is to investigate the diagnostic value of electrocardiographic QT parameters in AMI and their relationship with CT findings.

MATERIALS AND METHODS

Patients who were admitted to the emergency department with abdominal pain were recruited retrospectively from the hospital information system. Grouping was carried out on the basis of AMI (n=78) and non-AMI (n=78). In both groups, the corrected QT (QTc) and QT dispersion (QTD) were measured on electrocardiographs, and the qualitative and quantitative CT findings were evaluated on CT examinations.

RESULTS

The QTc and QTD values were higher in the AMI group. The median QTc values were 456.16 (IQR: 422.88-483.16) for the AMI group and 388.83 (IQR: 359.74-415.83) for the control group (p<0.001), and the median QTD values were 58 (IQR: 50.3-68.25) for the AMI group and 46 (IQR: 42-50) for the control group (p<0.001). In the CT analysis, the QTc values were significantly higher among AMI patients, with images of paper-thin bowel walls and the absence of bowel wall enhancement (p=0.042 and p=0.042, respectively). Meanwhile, the QTD values were significantly higher among patients with venous pneumatosis findings on CT (p=0.005). In the regression analysis, a significant relationship was found between the QT parameters and AMI (p<0.001). For QTc, an AUC of 0.903 (95% CI: 0.857-0.950, p<0.001), a sensitivity of 80.8%, and a specificity of 82.3% were found. For QTD, an AUC of 0.821 (95% CI: 0.753-0.889, p<0.001), a sensitivity of 73.1%, and a specificity of 82.3% were found.

CONCLUSION

We found the QTc and QTD values to be significantly higher among AMI patients. Furthermore, we found a significant relationship between the CT findings and QTc and QTD and a significant relationship between survival and QTc in the AMI group.

Preoperative prognostic predictors and treatment strategies for surgical procedure focused on the sequential organ failure assessment score in nonocclusive mesenteric ischemia: a multicenter retrospective cohort study

BACKGROUND

Several large-scale studies have assessed endovascular and surgical treatment methods for nonocclusive mesenteric ischemia (NOMI); however, the prognostic factors for NOMI remain unclear. Therefore, this study aimed to evaluate risk factors for in-hospital mortality among patients with NOMI who underwent laparotomy and to examine therapeutic strategies that may improve the prognosis.

MATERIALS AND METHODS

In this multicenter retrospective study, the authors reviewed the electronic medical records retrieved from the inpatient database of patients with NOMI at eight district general hospitals between January 2011 and January 2021. A total of 88 patients who underwent laparotomies were divided into survivor and nonsurvivor groups, and statistical analysis was performed to determine clinical and physiological factors.

RESULTS

Exploratory laparotomy based on second-look surgery was the first treatment choice. The overall mortality rate was 48.8%, with a male-to-female ratio of 1.1:1. The median Sequential Organ Failure Assessment (SOFA) score was 8 [interquartile range: 3.75-14.2], and the median SOFA scores were 5 [3-7] in the survivor group and 13 [9-17.5] in the nonsurvivor group. Univariate analysis revealed a significant difference in BMI ( P <0.001), hypoglycemia ( P =0.0012), previous cardiovascular surgery ( P =0.0019), catecholamine use ( P <0.001), SOFA score ( P <0.001), platelet count ( P =0.0023), and lactate level ( P <0.001). Logistic regression analysis using the factors with significant differences revealed that SOFA score ≥10 (odds ratio 23.3; 95% CI: 1.94-280.00; P =0.013) was an independent prognostic factor. In addition, catecholamine use was suggested as a factor with a SOFA score greater than or equal to 10.

CONCLUSION

This study confirmed that a SOFA score of greater than or equal to 10 may be associated with increased mortality. While closely monitoring low blood pressure and renal dysfunction, survival rates may be improved if surgical intervention is performed before the SOFA score reaches greater than or equal to 10.

Evaluation of Abdominal Emergencies

Early primary assessment and abdominal examination can often be enough to triage the patient with abdominal pain into those with less severe underlying pathologic condition from those with more acute findings. A focused history of the patient can then allow the clinician to develop their differential diagnosis. Once the differential diagnoses are determined, diagnostic imaging and laboratory findings can help confirm the diagnosis and allow for expeditious treatment and intervention.

Factors associated with the need for long-term total parenteral nutrition in survivors of acute superior mesenteric artery occlusion

BACKGROUND

Acute superior mesenteric artery (SMA) occlusion is an uncommon condition associated with high mortality. If extensive bowel resection is performed for patients with acute SMA occlusion and the patient survives, long-term total parenteral nutrition (TPN) may be needed due to short bowel syndrome. This study examined factors associated with the need for long-term TPN after the treatment of acute SMA occlusion.

METHODS

We retrospectively analyzed 78 patients with acute SMA occlusion. Patients were abstracted from a Japanese database from institutions with at least 10 patients with acute SMA occlusive disease from January 2015 through December 2020 RESULTS: Among the initial cohort there were 41/78 survivors. Of these, 14/41 (34%) required permanent TPN who were compared with those who did not require long-term TPN (27/41, 66%). Compared to patients in the non-TPN group, those in the TPN group had significantly shorter remaining small intestine (90.7 cm vs. 218 cm, P<0.01), more patients with time from onset to intervention >6 hours (P=0.02), pneumatosis intestinalis on enhanced computed tomography scan (P=0.04), ascites (Odds Ratio 11.6, P<0.01), and a positive smaller superior mesenteric vein sign (P= 0.03). These were considered significant risk factors for needing long-term TPN. Age, gender, underlying disease, presence of peritoneal sign, presence of shock requiring vasopressors, site of obstruction (proximal vs. distal), and initial treatment (surgery vs. interventional radiology vs. thrombolytic therapy) were not significantly different between the two groups. Long-term TPN was significantly associated with longer hospital stay (52 vs. 35 days, P=0.04). Multivariate analysis identified the presence of ascites as an independent risk factor for needing long-term TPN.

CONCLUSION

The need for permanent TPN after treatment of acute SMA occlusion is significantly associated with longer hospital stay, longer time to intervention, and characteristic imaging findings (pneumatosis intestinalis, ascites, Smaller SMV sign). Ascites is an independent risk factor.

LEVEL OF EVIDENCE

III.

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.

Acute management of mesenteric emergencies: Tailoring the solution to the problem

Acute mesenteric ischemia (AMI) constitutes a life-threatening problem that can result in death, multiorgan failure, and severe nutritional disability. Although AMI is a rare cause of acute abdominal emergencies, ranging between 1 and 2 individuals per 10,000, the morbidity and mortality rates are high. Arterial embolic etiology composes nearly one-half of AMIs, with a sudden onset of severe abdominal pain considered the most common symptom. Arterial thrombosis is the second most common cause of AMI, which presents similarly to arterial embolic AMI, although often more severe due to anatomic differences. Veno-occlusive causes of AMI are the third most common and are associated with an insidious onset of vague abdominal pain. Each patient is unique, and the treatment plan should be tailored to their individual needs. This may include considering the patient's age, comorbidities, and overall health, as well as their preferences and personal circumstances. A multidisciplinary approach involving specialists from different fields, such as surgeons, interventional radiologists, and intensivists, is recommended for the best possible outcome. Potential challenges in tailoring an optimal treatment plan for AMI may include delayed diagnosis, limited availability of specialized care, or patient factors that make some interventions less feasible. Addressing these challenges requires a proactive and collaborative approach, with regular review and adjustment of the treatment plan as needed to ensure the best possible outcome for each patient.

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.

Midterm Clinical Outcomes of Retrograde Open Mesenteric Stenting for Mesenteric Ischemia

BACKGROUND

Retrograde open mesenteric stenting (ROMS) has become a mainstay in treatment of mesenteric ischemia; however, follow-up in contemporary studies is limited.

METHODS

A single-center retrospective review of patients undergoing ROMS from 2007 to 2020 was conducted. Demographics, presentation, and procedural details were reviewed. End points were morbidity and mortality, technical success, primary patency, reinterventions, and freedom from clinical recurrence.

RESULTS

ROMS was performed in 34 patients, 19 female (56%). Mean age was 71 ± 10 years. Eighteen patients (53%) presented with acute mesenteric ischemia (AMI), 11 (32%) with acute-on-chronic, and 5 (15%) with chronic mesenteric ischemia. Etiology was chronic atherosclerosis with/without in-situ thrombosis in 28 patients (82%), superior mesenteric artery dissection in 3, and 1 each with embolic, vasculitic, and nonocclusive ischemia. Four patients (12%) had prior mesenteric procedures (3 Celiac/1 superior mesenteric artery stent) and 1 had unsuccessful transbrachial stenting attempt. Technical success, defined as successful stenting through a retrograde approach was attained in 31 patients (91%), with the 3 remaining patients treated with transbrachial stenting in 2 and iliomesenteric bypass in 1. Covered stents were used in 21 patients (64%) with or without stent extension with bare-metal stents. Eight patients (23%) required thromboembolectomy and 9 (26%) underwent patch angioplasty. Thirty-day mortality rate was 35%, all in patients with AMI (10) or acute-on-chronic (2). Eighteen patients (53%) underwent bowel resection, all presenting acutely. Early reinterventions within the first 30 days were required in 5 patients (15%), including 2 redo ROMS with thrombectomy and endarterectomy, 2 percutaneous stent extensions, and 1 aortic septum fenestration with coiling of a jejunal branch pseudoaneurysm. With a median follow-up of 3.7 (interquartile range: 0.8-5.0) years, in patients surviving discharge, 5 required reintervention yielding freedom from reintervention rates of 87% at 1 year and 71% at 3 years. All postdischarge reinterventions were endovascular with no conversion to bypass. The overall 1-year and 3-year primary patency rates were 70% and 61% (primary-assisted patency at 1 and 3 years was 87% and secondary patency at 1 and 3 years was 97%). The freedom from symptom recurrence was 95% at 1 and 3 years.

CONCLUSIONS

ROMS carries high rates of technical success in patients with mesenteric ischemia, despite a high chronic atherosclerotic burden. Although mid-term patency rates are acceptable, AMI is still associated with high early morbidity and mortality, with high rates of associated bowel resection. ROMS is a valuable tool in the armamentarium of vascular surgeons.

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.

Role of clinical data and multidetector computed tomography findings in acute superior mesenteric artery embolism

BACKGROUND

Superior mesenteric artery embolism (SMAE) has acute onset and fast progression, which seriously threatens the life of patients. Multidetector computed tomography (MDCT) is one of the most important diagnostic methods for SMAE, which plays an important role in the diagnosis and prognosis of SMAE.

AIM

To evaluate the value of combined clinical data and MDCT findings in the diagnosis of acute SMAE and predict the risk factors for SMAE-related death.

METHODS

Data from 53 SMAE patients who received abdominal MDCT multi-phase enhancement and superior mesenteric artery digital subtraction angiography examinations were collected. Univariate cox regression and multivariate cox model were used to analyze the correlation between death risk and clinical and computed tomography features in SMAE patients.

RESULTS

Univariate Cox regression model showed that intestinal wall thinning, intestinal wall pneumatosis, blood lactate > 2.1 mmol/L and blood pH < 7.35 increased the risk of death in patients with SMAE. After adjusting for age, sex, embolic involvement length and embolic distribution region, multivariate Cox regression model I showed that blood lactate > 2.1 mmol/L (HR = 5.26, 95%CI: 1.04-26.69, P = 0.045) and intestinal wall thinning (HR = 9.40, 95%CI: 1.05-83.46, P = 0.044) were significantly increases the risk of death in patients with SMAE.

CONCLUSION

For patients with SAME, increased blood lactate and intestinal wall thinning are the risk factors for death; hence, close monitoring may reduce the mortality rate. Clinical observation combined with MDCT signs can significantly improve SMAE diagnosis.

Acute Mesenteric Ischemia

The surgical treatment of occlusive acute mesenteric ischemia (AMI) without revascularization is associated with an 80% overall mortality. Early diagnosis is crucial, and revascularization may reduce overall mortality in AMI by up to 50%. A diagnosis of AMI requires a high index of clinical suspicion and the collaborative effort of emergency department physicians, general and vascular surgeons, and radiologists. This article provides an overview of the etiology, physiology, evaluation, and management of acute mesenteric ischemia.

Outcome Comparison of Endovascular and Open Surgery for the Treatment of Acute Superior Mesenteric Artery Embolism: A Retrospective Study

Background

Few centers have adopted endovascular revascularization for the treatment of superior mesenteric artery embolism (SMAE). We sought to evaluate the efficacy of endovascular therapy for the treatment of SMAE and identify post-treatment prognostic factors.

Methods

The clinical data of 41 patients with acute SMA embolism between 2013 and 2021 were retrospectively reviewed. Patients with mesenteric artery thrombosis, mesenteric venous thrombosis, and who had only conservative treatment were excluded.

Results

Forty-one consecutive patients were identified with SMAE (median age, [range] 35–86 years). Endovascular therapy was initiated in 14 patients with no clinical evidence of bowel necrosis, with mainly mechanical thrombectomy, and technical success was achieved in 93%. Endovascular therapy had advantages in duration surgery time, blood loss, bowel rest time, ICU time, and ventilator use. There was no difference in bowel necrosis, length of necrotic bowel resected, or in-hospital mortality between the two groups. An initial white blood cell (WBC) count >15 × 103/dl and neutrophil count >13 × 103/dl were associated with an increased risk of bowel necrosis, and an initial WBC count, renal function, American Society of Anesthesiologists (ASA >3) and necrotic bowel >2 m were associated with increased mortality.

Conclusions

Endovascular treatment has altered the management of SMAE, and it may be adopted in selected patients who are not at risk for bowel necrosis. Avoidance of bowel necrosis patients and close monitoring for bowel necrosis are important.

Review of Mesenteric Ischemia in COVID-19 Patients

The new coronavirus (COVID-19) infection, first detected in Wuhan, China in 2019 has become a pandemic that has spread to nearly every country in the world. Through October 11, 2021, more than 23 billion confirmed cases and 4.8 million fatalities were reported globally. The bulk of individuals afflicted in India during the first wave were elderly persons. The second wave, however, resulted in more severe diseases and mortality in even younger age groups due to mutations in the wild virus. Symptoms may range from being asymptomatic to fatal acute respiratory distress syndrome (ARDS). In addition to respiratory symptoms, patients may present with gastrointestinal symptoms such as stomach pain, vomiting, loose stools, or mesenteric vein thrombosis. The frequency of patients presenting with thromboembolic symptoms has recently increased. According to certain studies, the prevalence of venous thromboembolism among hospitalized patients ranges from 9 to 25%. It was also shown that the incidence is significantly greater among critically sick patients, with a prevalence of 21–31%. Although the exact origin of thromboembolism is unknown, it is considered to be produced by several altered pathways that manifest as pulmonary embolism, myocardial infarction, stroke, limb gangrene, and acute mesenteric ischemia. Acute mesenteric ischemia (AMI) is becoming an increasingly prevalent cause of acute surgical abdomen in both intensive care unit (ICU) and emergency room (ER) patients. Mesenteric ischemia should be evaluated in situations with unexplained stomach discomfort. In suspected situations, appropriate imaging techniques and early intervention, either non-surgical or surgical, are necessary to avert mortality. The purpose of this article is to look at the data on acute mesenteric ischemia in people infected with COVID-19.

Mesenteric and myocardial ischemia revealing lower limb sarcoma

Introduction and importance

Although most of the causes of acute superior mesenteric artery (SMA) embolism with a poor clinical course originate from the heart, we report a case of SMA embolism secondary to advanced sarcoma of the lower extremities.

Case presentation

A 66-year-old man presented with chest and epigastric discomfort that lasted for 1 day. Coronary angioplasty was performed, followed by laparotomy with an embolectomy of the SMA, small bowel resection, and ileostomy. After surgery, leiomyosarcoma was diagnosed on a biopsy performed in the left thigh, and lung metastasis was confirmed. He had recurrent peritonitis for 2 months and died of multiple organ failure.

Clinical discussion

The common etiologies of SMA embolism include cardioembolic sources with atrial fibrillation and recent myocardial infarction. Rare etiologies include atherosclerotic plaque, mural thrombus of the aneurysm, and cardiac sarcoma.

Conclusion

Efforts are required for the systemic evaluation of various etiologies in patients with SMA embolism who require rapid diagnosis and intervention.

•

Mesenteric ischemia and myocardial ischemia caused by advanced sarcoma of lower extremities are rare.

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When evaluating patients with SMA embolism, systemic evaluation of various etiologies is required.

•

We present a case of SMA embolism secondary to advanced sarcoma of the lower extremities.

Monitoring the Sequential Organ Failure Assessment score in nonocclusive mesenteric ischemia increases the survival rate: A single-center observational study

Several large-scale studies have assessed the endovascular and surgical treatments for nonocclusive mesenteric ischemia (NOMI); nonetheless, the prognostic factors for NOMI remain unclear.In this single-center study, we retrospectively reviewed the electronic medical records of 197, 149 patients were retrieved from the inpatient database of our hospital from January 2011 to January 2020; 79 patients with NOMI were observed. A total of 44 patients who underwent laparotomy were statistically analyzed and divided into the survivor and non-survivor groups. Prognostic factors were compared between the 2 groups. Exploratory laparotomy based on a second-look surgery was the first treatment choice.The overall mortality rate was 61.3%, with a male-to-female ratio of 1.6:1. The median Sequential Organ Failure Assessment (SOFA) score was 11.06 [5.75-17.25]. The median SOFA score was 5 [interquartile range: 3-8] in the survivor group and 14.8 [interquartile range: 10.5-19] in the non-survivor group. The log-rank test showed a significant difference in the presence of diabetes mellitus (P = .025), hypoglycemia (P = .001), SOFA score ≥10 (P < .001), hemoglobin levels ≥11 g/dL (P = .003), platelet count ≥12.9 × 104/μL (P = .01), lactate levels ≥2.6 mmol/L (P = .005), and base excess <-3.0 (P < .023). Multivariate analysis using the factors with significant differences revealed that SOFA score ≥10 (hazard ratio for death, 1.199; 95% confidence interval, 1.101-1.305; P < .001) was an independent prognostic factor.The SOFA score can be used to assess disease severity. A SOFA score of ≥10 may be associated with increased mortality.

Acute Mesenteric Ischemia in a COVID-19 Patient: Delay in Referral and Recommendation for Surgery

Coronavirus (COVID-19) is more common with symptoms such as fever, dry cough, and shortness of breath. However, it may be associated with COVID-19-induced gastrointestinal (GI) symptoms including acute mesenteric ischemia (AMI). These conditions make the diagnosis of AMI challenging. Timely referral with correct diagnosis and attention to the uncommon symptoms of COVID-19 can play an important role in the management and treatment of AMI in COVID-19 patients. We present a patient with AMI due to thrombotic complications of COVID-19, who referred to the hospital too late and ignored the recommendation for abdominal surgery.

Laparoscopy in Emergency: Why Not? Advantages of Laparoscopy in Major Emergency: A Review

A laparoscopic approach is suggested with the highest grade of recommendation for acute cholecystitis, perforated gastroduodenal ulcers, acute appendicitis, gynaecological disorders, and non-specific abdominal pain (NSAP). To date, the main qualities of laparoscopy for these acute surgical scenarios are clearly stated: quicker surgery, faster recovery and shorter hospital stay. For the remaining surgical emergencies, as well as for abdominal trauma, the role of laparoscopy is still a matter of debate. Patients might benefit from a laparoscopic approach only if performed by experienced teams and surgeons which guarantee a high standard of care. More precisely, laparoscopy can limit damage to the tissue and could be effective for the reduction of the overall amount of cell debris, which is a result of the intensity with which the immune system reacts to the injury and the following symptomatology. In fact, these fragments act as damage-associated molecular patterns (DAMPs). DAMPs, as well as pathogen associated molecular patterns (PAMPs), are recognised by both surface and intracellular receptors of the immune cells and activate the cascade which, in critically ill surgical patients, is responsible for a deranged response. This may result in the development of progressive and multiple organ dysfunctions, manifesting with acute respiratory distress syndrome (ARDS), coagulopathy, liver dysfunction and renal failure. In conclusion, none of the emergency surgical scenarios preclude laparoscopy, provided that the surgical tactic could ensure sufficient cleaning of the abdomen in addition to resolving the initial tissue damage caused by the “trauma”.

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.

Acute Mesenteric Ischemia: A Challenge for the Acute Care Surgeon

Acute mesenteric ischemia is considered uncommon, but it appears to be more frequent cause of acute abdomen than appendicitis or ruptured abdominal aortic aneurysm in elderly patients. Surgical treatment without revascularization is associated with high overall mortality, up to 80%. The modern treatment of acute mesenteric ischemia requires collaboration of gastrointestinal surgeons, vascular surgeons, and interventional radiologists. Early revascularization may reduce the overall mortality associated with acute mesenteric ischemia by up to 50%. Clinical suspicion and contrast-enhanced computed tomography performed at early stage are keys to improve outcomes of acute mesenteric ischemia treatment. This review summarizes what the acute care surgeon needs to know about acute mesenteric ischemia with special emphasis on slowly progressing "acute on chronic" mesenteric ischemia.

Many faces of acute bowel ischemia: overview of radiologic staging

Acute bowel ischemia (ABI) can be life threatening with high mortality rate. In spite of the advances made in diagnosis and treatment of ABI, no significant change has occurred in the mortality over the past decade. ABI is potentially reversible with prompt diagnosis. The radiologist plays a central role in the initial diagnosis and preventing progression to irreversible intestinal ischemic injury or bowel necrosis. The most single imaging findings described in the literature are either non-specific or only present in the late stages of ABI, urging the use of a constellation of features to reach a more confident diagnosis. While ABI has been traditionally categorized based on the etiology with a wide spectrum of imaging findings overlapped with each other, the final decision for patient’s management is usually made on the stage of the ABI with respect to the underlying pathophysiology. In this review, we first discuss the pathologic stages of ischemia and then summarize the various imaging signs and causes of ABI. We also emphasize on the correlation of imaging findings and pathological staging of the disease. Finally, a management approach is proposed using combined clinical and radiological findings to determine whether the patient may benefit from surgery or not.

Interdisciplinary approach in emergency revascularization and treatment for acute mesenteric ischemia

Background

Mesenteric ischemia is associated with poor outcome and high overall mortality. The aim was to analyze an interdisciplinary treatment approach of vascular and visceral specialists focusing on the in-hospital outcome and follow-up in patients with acute and acute-on-chronic mesenteric ischemia.

Methods

From 2010 until 2017, 26 consecutive patients with acute or acute on chronic mesenteric ischemia were treated by an interdisciplinary team. Data were prospectively collected and retrospectively evaluated. Throughout the initial examination, the extent of bowel resection was determined by the visceral surgeon and the appropriate mode of revascularization by the vascular surgeon. The routine follow-up included clinical examination and ultrasound- or CT-imaging for patency assessment and overall survival as primary endpoint of the study.

Results

Out of 26 patients, 18 (69.2%) were rendered for open repair. Ten patients (38.5%) received reconstruction of the superior mesenteric artery with an iliac-mesenteric bypass. Seven patients (26.9%) underwent thrombembolectomy of the mesenteric artery. One patient received an infra-diaphragmatic aorto-celiac-mesenteric bypass. Out of the 8 patients, who were not suitable for open revascularization, 2 patients (7.7%) were treated endovascularly and 6 (23.1%) underwent explorative laparotomy.

The in-hospital mortality was 23% (n = 6). The mean survival of the revascularized group (n = 20) was 51.8 months (95% CI 39.1–64.5) compared to 15.7 months in the non-revascularized group (n = 6) (95% CI − 4.8–36.1; p = 0.08). The median follow-up was 64.6 months. Primary patency in the 16 patients after open and 2 after interventional revascularization was 100% and 89.9% in the follow-up.

Conclusion

The interdisciplinary treatment of mesenteric ischemia improves survival if carried out in time. Hereby open revascularization measures are advantageous as they allow bowel assessment, resection, and revascularization in a one-stop fashion especially in advanced cases.

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.

Protective Effects of Cinnamaldehyde against Mesenteric Ischemia-Reperfusion-Induced Lung and Liver Injuries in Rats

The aim of this study was to characterize and reveal the protective effects of cinnamaldehyde (CA) against mesenteric ischemia-reperfusion- (I/R-) induced lung and liver injuries and the related mechanisms. Sprague-Dawley (SPD) rats were pretreated for three days with 10 or 40 mg/kg/d, ig of CA, and then induced with mesenteric ischemia for 1 h and reperfusion for 2 h. The results indicated that pretreatment with 10 or 40 mg/kg of CA attenuated morphological damage in both lung and liver tissues of mesenteric I/R-injured rats. CA pretreatment significantly restored the levels of aspartate transaminase (AST) and alanine transaminase (ALT) in mesenteric I/R-injured liver tissues, indicating the improvement of hepatic function. CA also significantly attenuated the inflammation via reducing myeloperoxidase (MOP) activity and downregulating the expression of inflammation-related proteins, including interleukin-6 (IL-6), interleukin-1β (IL-1β), cyclooxygenase-2 (Cox-2), and tumor necrosis factor receptor type-2 (TNFR-2) in both lung and liver tissues of mesenteric I/R-injured rats. Pretreatment with CA significantly downregulated nuclear factor kappa B- (NF-κB-) related protein expressions (NF-κB p65, NF-κB p50, I kappa B alpha (IK-α), and inhibitor of nuclear factor kappa-B kinase subunit beta (IKKβ)) in both lung and liver tissues of mesenteric I/R-injured rats. CA also significantly downregulated the protein expression of p53 family members, including caspase-3, caspase-9, Bax, and p53, and restored Bcl-2 in both lung and liver tissues of mesenteric I/R-injured rats. CA pretreatment significantly reduced TUNEL-apoptotic cells and significantly inhibited p53 and NF-κB p65 nuclear translocation in both lung and liver tissues of mesenteric I/R-injured rats. CA neither induced pulmonary and hepatic histological alterations nor affected the parameters of inflammation and apoptosis in sham rats. We conclude that CA alleviated mesenteric I/R-induced pulmonary and hepatic injuries via attenuating apoptosis and inflammation through inhibition of NF-κB and p53 pathways in rats, suggesting the potential role of CA in remote organ ischemic injury protection.

Isolated superior mesenteric artery dissection: CTA features and clinical relevance

PURPOSE

To determine the detailed computed tomography angiography (CTA) features of isolated superior mesenteric artery dissection (ISMAD), aiming to improve the current understanding of ISMAD.

MATERIALS AND METHODS

We retrospectively analyzed 57 patients with confirmed diagnoses of ISMAD with CTA from June 2011 to June 2018 in our hospital. The superior mesenteric artery (SMA) angle, entry site of dissection, and features of both false and true lumen were analyzed individually.

RESULTS

In general, middle-aged men with atherosclerosis (42.1%), hypertension (35.3%), or long-term smoking (33.3%) were the main populations. 80.7% of patients can be discharged successfully after conservative treatment. 87% of patients had a right (or almost right) SMA angle, and the entry site of dissection in 90% of patients occurred in the curved segment of the SMA. As a polymorphic disease, we can use the coded CTA features to delineate individual cases, including cases beyond the presenting classification systems. The diameter of the true lumen is the only different CTA feature between the conservative treatment group and the interventional treatment group (p = 0.000). The re-entry site (p = 0.501), thrombosis in the false lumen (p = 0.135), the distance between the entry site of dissection and SMA root (p = 0.133), and SMA branch involvement (p = 0.322) had no difference between the 2 groups.

CONCLUSIONS

Based on CTA analysis, the bending area, especially in the SMA with right or nearly right SMA angle, is the most vulnerable anatomical region for the occurrence of ISMAD. The diameter of true lumen is the determined CTA feature for the decision of treatment. CTA should be recommended as a standardized diagnostic and classification tool for ISMAD.

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.

Isquemia intestinal por trombosis mesentérica en paciente geriátrico, resuelta por intervencionismo. Reporte de caso

Mesenteric thrombosis represents a vascular urgency caused by the abrupt interruption of blood flow, whether arterial or venous; clinical presentation can be nonspecific, which can represent a diagnostic challenge. According to its vascular etiology, a different therapeutic approach is required. If there is clinical suspicion or signs of peritonitis, the imaging diagnosis can support to identify the presented pathology. On this occasion, there is a clinical case of an 84-year-old http://doi.org/10.22201/fm.24484865e.2020.63.2.04 | Vol. 63, n.o 2, Marzo-Abril 2020 25 patient who goes to the emergency department for generalized abdominal pain, which led to a diagnostic imaging study, to confirm this finding. Key words: Intestinal ischemia; atherosclerosis; Mesenteric thrombosis; catheterization

Risk of acute mesenteric ischemia in patients with diabetes: A population-based cohort study in Taiwan

BACKGROUND AND AIMS

Diabetes is a common and complex endocrine disorder that often results in hyperglycemia, which has been strongly implicated in several cardiovascular and cerebrovascular events that cause disability. Acute mesenteric ischemia (AMI) is a vascular emergency with high mortality rates. We conducted a population-based cohort study that utilizes data from medical claims databases to investigate whether diabetes increases the risk of AMI.

METHODS

Using claims data from Taiwan's National Health Insurance program, 66,624 diabetic patients were enrolled from 1998 to 2009, and a comparison group of 266,496 individually matched subjects without diabetes was selected. The two groups were followed up until diagnosis of AMI, death, or the end of 2011. Incidence rates of AMI were assessed in both groups. Cox proportional hazards models were used to estimate the hazard ratios of diabetes for AMI.

RESULTS

The diabetes cohort had a higher incidence rate than the comparison cohort for AMI (0.56 vs. 0.29 per 1,000 person-years). After adjusting for sex, age, comorbidity, and health system utilization, the adjusted hazard ratio of diabetes was 1.32 (95% confidence interval 1.11-1.56) for AMI. The risk of AMI associated with diabetes was greater in men (adjusted hazard ratio = 1.48, 95% confidence interval 1.17-1.87) than in women (adjusted hazard ratio = 1.17, 95% confidence interval 0.92-1.49).

CONCLUSIONS

There was an increased risk of AMI in patients with diabetes. However, further research is required to understand whether this association is causal or due to a common set of risk factors.

Early laparoscopic exploration for acute mesenteric ischemia after cardiac surgery

Acute mesenteric ischemia (AMI) after cardiac surgery is a rare but fatal complication. Early diagnosis and intervention can be lifesaving. We report two cases of patients who underwent early diagnostic laparoscopy for suspicious AMI after cardiac surgery and demonstrated favorable outcomes. An 83-year-old male with severe left ventricular dysfunction underwent off-pump coronary artery bypass grafting. Severe ileus with gaseous distension of the small bowel was developed on the 3rd postoperative day and computed tomographic angiography (CTA) showed pneumatosis intestinalis of small bowel suggestive of AMI. An immediate bedside laparoscopy was performed and it showed preserved perfusion of small bowel. He recovered without complication under supportive medical management. Another 69-year-old male who underwent aortic valve replacement complained of whole abdominal tenderness with severe distension on the 3rd postoperative day. The CTA found segmental non-enhancing bowel wall with air bubbles suggestive of AMI with possible microperforation. A diagnostic laparoscopy demonstrated small-bowel infarction with pus-like fluid collection in the peritoneal cavity. The operation was converted to laparotomy and complete resection of ischemic segments of small bowel was done. He recovered well without any other complications and discharged home on the 35th postoperative day.

Acute mesenteric ischemia-like syndrome associated with suspected Spirocerca lupi aberrant migration in dogs

OBJECTIVE

To describe acute mesenteric infarction due to suspected Spirocerca lupi aberrant migration in 5 dogs.

CASE SERIES SUMMARY

All dogs were large breed, none of which exhibited typical clinical signs associated with spirocercosis. All dogs were eventually diagnosed with septic peritonitis. On exploratory laparotomy, thickening of the jejunal arteries, surrounding mesojejunum, and segmental necrosis were identified. Similar thickening and hematoma formation were found in other regions of the mesentery. In 4 of the cases, the necrotic segment was located in the distal jejunum. Histology revealed thrombotic mesenteric vessels with intralesional S. lupi nematode larvae. Resection and anastomosis of the necrosed section was performed and all but 1 dog survived and were discharged within 1-6 days.

NEW OR UNIQUE INFORMATION PROVIDED

Spirocerca lupi is a potential cause of mesenteric infarction in endemic areas when no other obvious etiology is identified.

Effect of timing on endovascular therapy and exploratory laparotomy outcome in acute mesenteric ischemia

Background

Abdominal exploration followed by vascular bypass has been the standard of care for acute mesenteric ischemia (AMI), but there is increasing use of endovascular treatment with selective exploratory laparotomy.

Methods

We performed a retrospective review of patients diagnosed with AMI who underwent mesenteric artery angioplasty or stenting at a single institution from 2010-2017. Patients were divided into 3 groups: those who did not undergo exploratory laparotomy; those who received endovascular treatment before laparotomy (post-reperfusion laparotomy group); and those who had endovascular treatment after laparotomy (pre-reperfusion laparotomy group).

Results

Patients who did not undergo exploratory laparotomy showed 85.7% (12/14) survival, compared with 63.6% (7/11) in the post-reperfusion group and 25.0% (2/8) in the pre-reperfusion group, P=0.077). Time to reperfusion was significant (P=0.009) in predicting survival for patients who underwent exploratory laparotomy.

Conclusion

Emergent endovascular treatment prior to laparotomy seems to be associated with a higher survival.

The Superior Mesenteric Artery: From Syndrome in the Young to Vascular Atherosclerosis in the Old

This review is directed at increasing awareness of two diverse rare upper gastrointestinal problems that occur at opposite ends of the age spectrum and are difficult to diagnose and treat. The Superior Mesenteric Artery Syndrome (SMAS) likely involves a young patient, especially female, and is especially associated with rapid weight loss, resulting in relative strangulation of the duodenum by a narrowing of the angle between the Superior Mesenteric Artery (SMA) and the aorta. On the other hand, atherosclerosis of the SMA is associated most likely with postprandial upper intestinal ischemia and abdominal pain occurs in the elderly at high risk for cardiovascular (CV) disease. Medical management of the SMAS in the young involves good alimentation and weight gain to overall increase the intestinal fat pad. Medical management of SMA atherosclerotic ischemia in the elderly is directed at marked lipid lowering with atherosclerotic plaque stabilization or even regression. If needed, surgery for SMAS can be attempted laparoscopically with duodenojejunoscopy which is the most popular procedure but there are also more conservative possibilities that avoid division of the duodenum. In addition, sometimes direct vision is needed to successfully operate on SMAS. If surgery is needed for SMA atherosclerotic ischemia, it is usually attempted endoscopically with angioplasty and stent placement. Most important, in the case of these two rare clinical entities, is that the clinician have a suspicion of their presence when indicated so that the young or old patient can be spared unnecessary suffering and return to good health in a timely fashion.

The Role of Ultrasonography in Patients Referring to the Emergency Department with Acute Abdominal Pain

CONTEXT

Acute abdominal pain is a common clinical problem in emergency and non-emergency cases accounting for 5 to 10% of all referrals to the emergency department. Studies have indicated that these widely differentiated diagnoses are common to these complaints. Considering the high prevalence of this complaint in the patients and the wide range of its differential diagnosis, this review study was designed and evaluated aiming at investigating the causes of acute abdominal pain with a focus on assessing the position of ultrasound as a diagnostic tool in the emergency department.

EVIDENCE ACQUISITION

This article was conducted as a narrative review of selected articles from 2005 through 2019. By comparing them, a comprehensive review of ultrasound role was conducted in patients with acute abdominal pain referring to the emergency department.

RESULTS

In this review study, we attempted to use the articles of the clinical approach, the required laboratory tests, the disadvantages and advantages of each imaging technique, the differential diagnosis for acute abdominal pain according to the location of the pain, and the position of ultrasound as a diagnostic aid tool. Eventually, the proposed protrusion will be considered in dealing with a patient with acute abdominal pain.

CONCLUSION

Regarding the wide range of causes providing multiple differential diagnosis, as well as the limited time of the health team in the emergency department for diagnostic and therapeutic measures, particularly in time-sensitive clinical conditions, ultrasound offered by emergency medicine specialists as a diagnostic aid is considered to improve the overall diagnosis and treatment of patients, thereby reducing complications.

What predicts the outcome in patients with intestinal ischemia? A single center experience

BACKGROUND

Acute mesenteric ischemia (AMI) is associated with a mortality of 60-80%. Early diagnosis and rapid treatment have a decisive influence on therapy. The aim of this study was to evaluate the prognostic value of AMI markers on mortality, in order to better anticipate the clinical course and to initiate therapeutic steps at an early stage.

STUDY DESIGN

An analysis from our prospective database of 302 consecutive patients with AMI who were treated surgically in the Department of General Surgery between February 2003 and October 2014 was performed. Uni- and multivariate analysis of risk factors for mortality have been performed in the total cohort and in two subgroups according to their stay in intensive care unit (ICU) at the time of AMI diagnosis.

RESULTS

Of the 302 patients with AMI, 115 were in ICU at the time of diagnosis. Totally, 203 patients underwent computed tomography scan (CT-scan) of the abdomen for diagnosis and 68% of them showed specific signs of AMI. A total of 63 (21%) embolectomies were performed during the surgical procedure. The post-operative mortality rate was 68% (204 patients). Among survivors, 85 (87%) patients developed a short bowel syndrome in the post-operative course. Multivariate analysis showed a significant association between mortality and preoperative lactate>3mmol/L, C-reactive protein>100mg/L and ICU stay at the time of AMI diagnosis.

CONCLUSION

Mortality of patients with AMI remains high. Elevated lactate, elevated C-reactive protein and ICU stay are factors associated with increased mortality. Their presence in a patient with suspicion of AMI should trigger a multidisciplinary management in emergency.

Review: Acute superior mesenteric artery embolism: A vascular emergency cannot be ignored by physicians

BACKGROUND

Acute mesenteric ischemia (AMI) is a life-threatening medical condition that occurs when a sudden decreased perfusion to the intestines which leads to bowel infarction, and acute superior mesenteric artery embolism (ASMAE) is the main cause of AMI. Unfortunately, with the improvement of diagnosis and treatment technology, the mortality remains high due to less frequent clinical suspicion resulted from the unclear clinical manifestation and non-specific laboratory findings.

METHODS

Relevant studies published were identified by searching the PubMed, Embase and Cochrane Library databases. This review presented the literatures to introduce the research progress of ASMAE in recent years.

RESULTS

Patients with the history of atrial fibrillation, heart valve disease and atherosclerosis should be considered as ASMAE. Laboratory findings are insensitive and unspecific, however, angiography and Computed tomography angiography (CTA) can provide a clear diagnosis sensitively and specifically. Endovascular approaches have been increasingly reported in multiple case series. The key to successful treatment of AMI involves early clinical recognition and early intervention to move the embolus, which can reduce the rate of misdiagnosis and save the precious time and lives of patients.

CONCLUSIONS

Loss of time eventually leads to progression of ischemia to transmural bowel necrosis with peritonitis and septicemia, which may further worsen patients' outcomes. It is important for physicians to make a timely and accurate diagnosis, which can save precious time and reduce the mortality.

Contemporary Management of Acute Mesenteric Ischemia in the Endovascular Era

Objective:

Acute mesenteric ischemia is a rare disease entity associated with high morbidity and mortality. Disparate etiologies and nonspecific symptoms make the diagnosis challenging and often result in delayed diagnosis and intervention. Open laparotomy with mesenteric revascularization and resection of necrotic bowel has been considered the gold standard of care. With recent advances in percutaneous catheter-directed techniques, multiple retrospective studies have demonstrated the outcomes of endovascular therapy. Herein, we review the etiology, presentation, and diagnosis of acute mesenteric ischemia with contemporary outcomes associated with both open and endovascular treatments.

Methods:

The PubMed electronic database was queried in the English language using the search words mesenteric, acute ischemia, embolism, thromboembolism, thrombosis, revascularization, and endovascular in various combinations. Abstracts of the relevant titles were examined to confirm their relevance and the full articles then extracted. References from extracted articles were checked for any additional relevant articles. This systematic review encompassed literature for the past 5 years (between 2011 and 2016).

Results:

Early diagnosis and intervention improves acute mesenteric ischemia outcomes. Early restoration of mesenteric flow minimizes morbidity and mortality. In comparison to open laparotomy with mesenteric revascularization and resection of necrotic bowel, several retrospective studies using administrative data and single-center chart reviews demonstrate noninferior outcomes of an endovascular first approach in acute arterial mesenteric occlusion.

Conclusions:

For acute mesenteric arterial occlusive disease, both endovascular and open revascularization techniques are viable options. Although there is lack of level 1 evidence, single-center retrospective studies and administrative database studies demonstrated that an endovascular first approach may have improved outcomes in the immediate postoperative period. However, selection and other bias in these studies necessitate the need for definitive randomized prospective studies between endovascular and open mesenteric intervention. In contrast, mesenteric venous thrombosis may be treated with systemic anticoagulation without surgical revascularization. Catheter-directed thrombectomy and thrombolysis can be considered at the discretion of the clinician.

Machine learning for intraoperative prediction of viability in ischemic small intestine

OBJECTIVE

Evaluation of intestinal viability is essential in surgical decision-making in patients with acute intestinal ischemia. There has been no substantial change in the mortality rate (30%-93%) of patients with acute mesenteric ischemia (AMI) since the 1980s. As the accuracy from the first laparotomy alone is 50%, the gold standard is a second-look laparotomy, increasing the accuracy to 87%-89%. This study investigates the use of machine learning to classify intestinal viability and histological grading in pig jejunum, based on multivariate time-series of bioimpedance sensor data.

APPROACH

We have previously used a bioimpedance sensor system to acquire electrical parameters from perfused, ischemic and reperfused pig jejunum (7  +  15 pigs) over 1-16 h of ischemia and 1-8 h of reperfusion following selected durations of ischemia. In this study we compare the accuracy of using end-point bioimpedance measurements with a feedforward neural network (FNN), versus the accuracy when using a recurrent neural network with long short-term memory units (LSTM-RNN) with bioimpedance data history over different periods of time.

MAIN RESULTS

Accuracies in the range of what has been reported clinically can be achieved using FNN's on a single bioimpedance measurement, and higher accuracies can be achieved when employing LSTM-RNN on a sequence of data history.

SIGNIFICANCE

Intraoperative bioimpedance measurements on intestine of suspect viability combined with machine learning can increase the accuracy of intraoperative assessment of intestinal viability. Increased accuracy in intraoperative assessment of intestinal viability has the potential to reduce the high mortality and morbidity rate of the patients.

Arterial thrombosis in unusual sites: A practical review

While cardiovascular disease is common, occasionally hematologists and other practitioners will encounter patients with arterial thrombosis/infarction in unusual sites, without clear cause or obvious diagnostic and treatment paradigms. Contrary to the more commonly encountered cerebrovascular accident and cardiovascular disorders, the various infarctions outlined in this review have unique presentations, pathophysiology, workup, and treatments that all hematologists should be aware of. This review outlines the current literature on arterial thrombosis, with consideration given to anatomic sources and hypercoagulable associations, while focusing on the epidemiology, pathophysiology, provoking factors, and current recommended treatments for intracardiac thrombus, primary aortic mural thrombus, visceral infarctions, and cryptogenic limb ischemia to provide a useful and practical review for the practitioner.

MI: Not a Heart Attack but a Gut Attack

Mesenteric ischemia and infarction are infrequent but often deadly conditions in acute and critically ill patients. Mesenteric ischemia may be a primary admission diagnosis or may develop secondary to another diagnosis. Having a high index of suspicion for patients at risk of mesenteric ischemia and mesenteric infarction can alter a poor outcome. This article reviews the pathophysiology, risk factors, assessment, medical and nursing diagnoses, as well as collaborative management for mesenteric ischemia. Early identification of patients at risk and the appropriate diagnostic testing are stressed. Nurses armed with the knowledge of this condition are better able to provide safe care to their patients.

Acute Gut Ischemia

Acute mesenteric ischemia is a surgical emergency commonly caused by embolic or thrombotic occlusion of the superior mesenteric artery. Prompt diagnosis, fluid resuscitation, systemic anticoagulation, and mesenteric revascularization are key tenants to the treatment of this lethal condition. Revascularization can be performed via open thromboembolectomy or surgical bypass, endovascular techniques, or a hybrid approach of the 2. Despite technological advancements, mortalities remain high, and the plan of care and revascularization should be based on the patient's clinical status and available medical center resources.

The Ongoing Challenge of Acute Mesenteric Ischemia

Background

The lethality of acute mesenteric ischemia (AMI) remains quite high with 50-70%. The main reasons for that are the fact that AMI is rarely taken into consideration by the differential diagnosis of acute abdomen, the time-consuming diagnostic process, and the lack of a standardized therapeutic concept. The present interdisciplinary review aims to increase awareness among physicians and to help improve clinical outcomes.

Methods

This clinical therapeutic review is based on author expertise as well as a selective literature survey in PubMed based on the term 'mesenteric ischemia', combined with the terms 'arterial', 'clinical presentation', 'diagnosis', 'therapy', 'surgery', and 'interventional radiology'. Based on these search results as well as on the guidelines of the German Society of Vascular Surgery, the American College of Cardiology, and the American Heart Association, we present an interdisciplinary treatment concept.

Results

AMI is a vascular emergency that can be successfully treated only within the first hours after the onset of symptoms. Computed tomography angiography is the diagnostic method of choice. Intensive care unit treatment can prevent the occurrence of multiple organ failure. Treatment primarily consists of the revascularization of the mesenteric arteries. Endovascular techniques should be given priority, whereas signs of peritonitis or a central arterial occlusion with high thrombus load primarily require a surgical approach in order to save time and increase patient safety. Additional bowel resections can play a significant role in the treatment of intestinal sepsis.

Conclusion

Prompt and goal-oriented diagnosis and consistent treatment of AMI within 4-6 h from the onset of symptoms can be decisive for the reduction of AMI-associated lethality. In order for this to happen, a standardized concept of emergency treatment needs to be implemented.

Small intestinal ischemia and reperfusion-bioimpedance measurements

OBJECTIVE

Trans-intestinal bioimpedance measurements have previously been used to investigate changes in electrical parameters during 6 h of ischemia in the small intestine. Knowledge is lacking regarding the time course of trans-intestinal bioimpedance parameters during reperfusion. As reperfusion is an important part in the clinical treatment of intestinal ischemia, we need to know how it affects the bioimpedance measurements.

APPROACH

We performed bioimpedance measurements, using a two-electrode setup on selected segments of the jejunum in 15 pigs. A controlled voltage signal was applied while measuring the resulting current. In each pig, five or six 30 cm segments of the jejunum were made ischemic by clamping the mesenteric arteries and veins creating segments with ischemia from 1-16 h duration. Reperfusion was initiated at selected time intervals of ischemia, and measured for 5-15 h afterwards.

MAIN RESULTS

The tan δ parameter (loss tangent) was different (p  <  0.016) comparing ischemic and control tissue for the duration of the experiment (16 h). Comparing the control tissue 30 cm from the ischemic area with the control tissue 60 cm from the ischemic tissue, we found that the mean tan δ amplitude in the frequency range (3900-6300 Hz) was significantly higher (p  <  0.036) in the proximal control after 10 h of experiment duration. After reperfusion, the time development of tanδm (loss tangent maximum over a frequency range) amplitude and frequency overlapped and periodically increased above the tanδm in the ischemic intestine. Dependent on the ischemic duration pre-reperfusion, the initial increase in tan δ stabilizes or increases drastically over time, compared to the tan δ amplitude of the ischemic tissue.

SIGNIFICANCE

As during ischemia, the electrical parameters during reperfusion also follow a characteristic time-course, depending on the ischemic exposure before pre-reperfusion. The temporal changes in electrical parameters during small intestinal ischemia followed by reperfusion provides important information for assessment of tissue injury.