Potential Indicators of Intestinal Necrosis in Portal Venous Gas: A Case Report of an 82-Year-Old Woman on Long-Term Hemodialysis with Ascites and Pneumatosis Coli.

BACKGROUND Several factors have been reported as possible predictors of intestinal necrosis in patients with portal venous gas (PVG). We describe potential indicators of intestinal necrosis in PVG identified by contrasting 3 episodes of PVG in a patient on hemodialysis against previously verified factors. CASE REPORT An 82-year-old woman undergoing hemodialysis was admitted to our hospital thrice for acute abdominal pain. On first admission, she was alert, with a body temperature of 36.3°C, blood pressure (BP) of 125/53 mmHg, pulse rate of 60/min, respiratory rate of 18/min, and 100% oxygen saturation on room air. Computed tomography (CT) revealed PVG, intestinal distension, poor bowel wall enhancement, bubble-like pneumatosis in the intestinal wall, and minimal ascites. PVG caused by intestinal ischemia was diagnosed, and she recovered after bowel rest and hydration. Three months later, she had a second episode of abdominal pain. BP was 115/56 mmHg. CT revealed PVG and a slight accumulation of ascites, without pneumatosis in the intestinal wall. She again recovered after conservative measures. Ten months later, the patient experienced a third episode of abdominal pain, with BP of 107/52 mmHg. CT imaging indicated PVG, considerable ascites, and linear pneumatosis of the intestinal walls. Despite receiving conservative treatment, the patient died. CONCLUSIONS A large accumulation of ascites and linear pneumatosis in the intestinal walls could be potential indicators of intestinal necrosis in patients with PVG caused by intestinal ischemia. As previously reported, hypotension was further confirmed to be a reliable predictor of intestinal necrosis.

Treatment outcomes in patients with acute thromboembolic occlusion of the superior mesenteric artery.

OBJECTIVES: The goals of this study were to investigate the treatment outcomes of acute thromboembolic occlusion of the superior mesenteric artery (ATOS) and identify prognostic factors after treatment. METHODS: The clinical data of 62 patients with ATOS between 2013 and 2021 were retrospectively reviewed. Patients were stratified by the treatment strategy, complications and mortality were compared in different group. RESULTS: Sixty-two consecutive patients were identified with ATOS. The median patient age was 69 years (interquartile range 58-79 years). Endovascular therapy was initiated in 21 patients, and 4 patients received conservative treatment. Open surgery was performed first in the remaining 37 patients. The technical success rates of the endovascular first group and open surgery group were 90.5% and 97.3%, respectively. One patient in the conservative treatment group had progression of ischemia to extensive bowel necrosis. There was no difference in 30-day mortality between these groups. Predictors of 30-day mortality included initial neutrophil count > 12* 103/dL, age over 60 years old and history of chronic renal insufficiency. CONCLUSIONS: Endovascular treatment or conservative treatment may be adopted in selected patients who do not exhibit signs and symptoms of bowel necrosis, and close monitoring for bowel necrosis is important. The increase in preoperative neutrophil count, age over 60 years old and history of chronic renal insufficiency were poor prognostic factors.

A visceral organ function-focused therapeutic strategy using a 6-hour time window for patients with acute type a aortic dissection complicated by mesenteric malperfusion.

BACKGROUND: Acute type A aortic dissection (ATAAD) complicated by mesenteric malperfusion is a critical and complicated condition. The optimal treatment strategy remains controversial, debate exists as to whether aortic dissection or mesenteric malperfusion should be addressed first, and the exact time window for mesenteric ischemia intervention is still unclear. To solve this problem, we developed a new concept based on the pathophysiological mechanism of mesenteric ischemia, using a 6-hour time window to divide newly admitted patients by the time from onset to admission, applying different treatment protocols to improve the clinical outcomes of patients with ATAAD complicated by mesenteric malperfusion. METHODS: This was a retrospective study that covered a five-year period. From July 2018 to December 2020(phase I), all patients underwent emergency open surgery. From January 2021 to June 2023(phase II), patients with an onset within 6 h all underwent open surgical repair, followed by immediately postoperative examination if the malperfusion is suspected, while the restoration of mesenteric perfusion and visceral organ function was performed first, followed by open repair, in patients with an onset beyond 6 h. RESULTS: There were no significant differences in baseline and surgical data. In phase I, eleven patients with mesenteric malperfusion underwent open surgery, while in phase II, our novel strategy was applied, with sixteen patients with an onset greater than 6 h and eleven patients with an onset less than 6 h. During the waiting period, none died of aortic rupture, but four patients died of organ failure, twelve patients had organ function improvement and underwent surgery successfully survived. The overall mortality rate decreased with the use of this novel strategy (54.55% vs. 18.52%, p = 0.047). Furthermore, the surgical mortality rate between the two periods showed even stronger statistical significance (54.55% vs. 4.35%, p = 0.022). Moreover, the proportions of patients with sepsis and multiorgan failure also showed differences. CONCLUSIONS: Our novel strategy for patients with ATAAD complicated by mesenteric malperfusion not only improves the surgical success rate but also reduces the overall mortality rate.

Identifying Factors Associated with Non-mesenterovascular Pathology in Patients Undergoing Surgical Treatment for Acute Mesenteric Ischemia.

AIM: To identify factors that can help us to avoid a preoperative incorrect diagnosis of vascular occlusion by evaluating patients who underwent laparotomy with a probable preoperative diagnosis of acute mesenteric ischemia (AMI), but later at laparotomy, were diagnosed to have a different pathology than AMI. MATERIAL AND METHODS: A total of 213 patients who were operated with the diagnosis of AMI were enrolled in this study. Based on their operational, clinical, and pathological findings, they were divided into two groups. Patient demographic data, along with the American Society of Anesthesiology (ASA) score, Charlson comorbidity index, history of previous abdominal surgery, and computed tomography (CT) findings were compared between groups. RESULTS: There were 37 patients in Group 1 (non-mesenterovascular pathology) and 176 patients in Group 2 (mesenterovascular pathology). The percentage of ASA 4 patients was higher in Group 2, with 48.3%, compared to 35.1% in Group 1 (p-value: 0.028). Upon admission, Group 2 had a higher rate of pathologic findings on CT examinations. 21.8% of the patients with non-mesenterovascular pathology had normal intra-abdominal findings. In univariate and multivariate analysis for no-nmesenterovascular pathology, patient age less than 65, Charlson comorbidity index 1-2, INR level >1.2, history of previous abdominal operation, and pneumatosis intestinalis were identified as independent risk factors. DISCUSSION: The possibility of non-mesenterovascular pathology in presumed AMI patients should be kept in mind, especially if the patients have a history of abdominal surgery, a low comorbidity index, an elevated international normalised ratio (INR), and are younger than 65 years of age. CONCLUSION: Evaluating the significant parameters identified in this study among patients with a preliminary diagnosis of AMI may prove useful in avoiding misdiagnosis and unnecessary surgeries.

[Indications and results of intestinal transplantation for short bowel syndrome after mesenteric ischemia]. / Indikation und Ergebnisse der Darmtransplantation bei Kurzdarmsyndrom nach mesenterialer Ischämie.

BACKGROUND: Intestinal transplantation (ITx) is the only causal treatment for complicated chronic intestinal failure after mesenteric ischemia and impending failure of parenteral supplementation. Isolated or combined ITx with the inclusion of the intestine is associated with demanding immunological, perioperative and infection associated challenges. AIM: The characterization of chronic intestinal failure, the indications, transplant survival, transplantation techniques and success rates. MATERIAL AND METHODS: Collection, summary and critical appraisal of international guidelines, the guidelines of the German Medical Chamber, and the international literature. RESULTS: The first successful ITx were performed in 1987 and 1988 at the University of Kiel Germany and the University of Pittsburgh, USA. The number of ITx rose continuously but in phases from the end of the 1990s to over 200 per year but has currently decreased to 100-150 per year due to optimized intestinal rehabilitation. While the 1­year and 3­year transplant survival rates were 30% and 20% before 1991, they increased in phases up to 60% and 50%, respectively, after 1995 and have now achieved almost 80% and 70%, respectively. CONCLUSION: The substantial improvement in the results of ITx can be partly explained by progress in operative techniques, intensive care medicine and a better understanding of mucosal immunity; however, optimized strategies in immunosuppression as well as prevention of infectious diseases and malignancies have also made decisive contributions.

Sestrin2 reduces ferroptosis via the Keap1/Nrf2 signaling pathway after intestinal ischemia-reperfusion.

Sestrins are metabolic regulators that respond to stress by reducing the levels of reactive oxygen species (ROS) and inhibiting the activity of target of rapamycin complex 1 (mTORC1). Previous research has demonstrated that Sestrin2 mitigates ischemia-reperfusion (IR) injury in the heart, liver, and kidneys. However, its specific role in intestinal ischemia-reperfusion (IIR) injury remains unclear. To elucidate the role of Sestrin2 in IIR injury, we conducted an experimental study using a C57BL/6J mouse model of IIR. We noticed an increase in the levels of Sestrin2 expression and indicators associated with ferroptosis. Our study revealed that manipulating Sestrin2 expression in Caco-2 cells through overexpression or knockdown resulted in a corresponding decrease or increase, respectively, in ferroptosis levels. Furthermore, our investigation revealed that Sestrin2 alleviated ferroptosis caused by IIR injury through the activation of the Keap1/Nrf2 signal pathway. This finding highlights the potential of Sestrin2 as a therapeutic target for alleviating IIR injury. These findings indicated that the modulation of Sestrin2 could be a promising strategy for managing prolonged IIR injury.

[Current management of acute Stanford type A aortic dissection complicated with mesenteric malperfusion].

The management of acute type A aortic dissection (aTAAD) with mesenteric malperfusion (MMP) is quite challenging as it is often associated with high mortality and poor outcomes, and an optimal treatment strategy is lack of consensus for this critically ill condition. Emergent open surgical repair of the ascending aorta is a life-saving operation and remains the standard of care for aTAAD with MMP, but is associated with a high rate of mortality. In recent years, reperfusion of superior mesenteric artery (SMA) by endovascular repair as the first treatment strategy in the treatment of aTAAD with MMP has been concerned and reported. Only endovascular repair and conservative medical treatment are also introduced in few cases with poor outcomes. There are many urgent issues that need to be addressed in current strategies. The optimal management strategies remain controversial, and further investigation and research are needed. These issues were addressed in this article.

Luminal Delivery of Pectin-Modified Oxygen Microbubbles Mitigates Rodent Experimental Intestinal Ischemia.

INTRODUCTION: Ischemic gut injury is common in the intensive care unit, impairs gut barrier function, and contributes to multiorgan dysfunction. One novel intervention to mitigate ischemic gut injury is the direct luminal delivery of oxygen microbubbles (OMB). Formulations of OMB can be modified to control the rate of oxygen delivery. This project examined whether luminal delivery of pectin-modified OMB (OMBp5) can reduce ischemic gut injury in a rodent model. METHODS: The OMBp5 formulation was adapted to improve delivery of oxygen along the length of small intestine. Adult Sprague-Dawley rats (n = 24) were randomly allocated to three groups: sham-surgery (SS), intestinal ischemia (II), and intestinal ischemia plus luminal delivery of OMBp5 (II + O). Ischemia-reperfusion injury was induced by superior mesenteric artery occlusion for 45 min followed by reperfusion for 30 min. Outcome data included macroscopic score of mucosal injury, the histological score of gut injury, and plasma biomarkers of intestinal injury. RESULTS: Macroscopic, microscopic data, and intestinal injury biomarker results demonstrated minimal intestinal damage in the SS group and constant damage in the II group. II + O group had a significantly improved macroscopic score throughout the gut mucosa (P = 0.04) than the II. The mean histological score of gut injury for the II + O group was significantly improved on the II group (P ≤ 0.01) in the proximal intestine only, within 30 cm of delivery. No differences were observed in plasma biomarkers of intestinal injury following OMBp5 treatment. CONCLUSIONS: This proof-of-concept study has demonstrated that luminal OMBp5 decreases ischemic injury to the proximal small intestine. There is a need to improve oxygen delivery over the full length of the intestine. These findings support further studies with clinically relevant end points, such as systemic inflammation and vital organ dysfunction.

Experiencia y factores perioperatorios que afectan a los resultados en isquemia mesentérica aguda. Resultados de un hospital terciario chileno / Experience and perioperative factors affecting results in acute mesenteric ischemia. Results of a Chilean tertiary hospital

Introducción y objetivo: la isquemia mesentérica es poco frecuente, pero tiene una alta mortalidad. Existen pocos reportes de esta patología en países subdesarrollados. Este estudio pretende describir los resultados de un centro universitario terciario chileno y los factores que afectan a su morbimortalidad. Material y métodos: análisis retrospectivo de los pacientes intervenidos de urgencia por isquemia mesentérica aguda entre 2016 y 2021 en el Hospital Clínico Universidad de Chile. Se excluyeron los pacientes manejados sin cirugía. Se analizaron factores perioperatorios, detalles operatorios, la mortalidad a 30 días y la estancia hospitalaria, entre otros. Resultados: se incluyeron 32 pacientes. La mediana de edad fue de 73,5 años (45-92). Las comorbilidades más frecuentes fueron hipertensión (62,5 %), diabetes mellitus (28,1 %) y enfermedad cardiovascular conocida: infarto agudo de miocardio, angina crónica, accidente cerebrovascular, isquemia aguda de extremidades y enfermedad arterial oclusiva periférica (34,4 %). El 40,6 % tenía causa arterial trombótica; el 18,8 %, arterial embólica; el 25 %, venosa, y el 15,6 %, no oclusiva (NOMI). El motivo de consulta más frecuente fue el dolor abdominal (84,4 %). En la primera intervención, el 81,3 % requirió resección intestinal. Se realizó una anastomosis en el 53,1 %. El 25 % de los pacientes fueron revascularizados, con un cirujano vascular en el equipo quirúrgico, en el 65,6 %. La mediana de estancia hospitalaria fue de 21 días (2-129). La mediana de tiempo a la cirugía fue de 10,75 horas (4,75-196)... (AU)

Introduction and objective: acute mesenteric ischemia has a low incidence but high mortality. The results of this disease are not well reported in developing countries. This study aims to describe the results of a Chilean tertiary university center and the factors that affect its morbidity and mortality. Material and methods: retrospective analysis of all patients undergoing emergency surgery for acute mesenteric ischemia between 2016 and 2021 at the hospital clínico universidad de chile. Patients managed without surgery were excluded. Demographic characteristics, perioperative factors, details of the first surgery, 30-day mortality, and hospital stay, among others, were analyzed. Results: 32 patients were included. The median age was 73.5 years (45-92). The most frequent comorbidities were arterial hypertension (62.5 %), diabetes mellitus (28.1 %) and known cardiovascular disease 34.4 % (acute myocardial infarction, chronic angina, cerebrovascular accident, acute limb ischemia, peripheral arterial occlusive disease). 40.6 % had a thrombotic arterial cause, 18.8 % embolic arterial, 25 % thrombotic venous and 15.6 % non-occlusive (NOMI). The most frequent reason for consultation was abdominal pain (84.4 %). In the first surgical intervention, 81.3 % required intestinal resection, with an anastomosis performed in 53.1 %. 25% were revascularized, with a vascular surgeon on the surgical team in 65.6 %. The median hospital stay was 21 (2-129) days. The median time from the emergency department to surgery was 10.75 hours (4.75-196). Mortality at 30 days was 40.6 %, with no differences between etiologies...(AU)

Covered versus bare-metal stenting of the mesenteric arteries in patients with chronic mesenteric ischaemia (CoBaGI): a multicentre, patient-blinded and investigator-blinded, randomised controlled trial.

BACKGROUND: Mesenteric artery stenting with a bare-metal stent is the current treatment for atherosclerotic chronic mesenteric ischaemia. Long-term patency of bare-metal stents is unsatisfactory due to in-stent intimal hyperplasia. Use of covered stents might improve long-term patency. We aimed to compare the patency of covered stents and bare-metal stents in patients with chronic mesenteric ischaemia. METHODS: We conducted a multicentre, patient-blinded and investigator-blinded, randomised controlled trial including patients with chronic mesenteric ischaemia undergoing mesenteric artery stenting. Six centres in the Netherlands participated in this study, including two national chronic mesenteric ischaemia expert centres. Patients aged 18 years or older were eligible for inclusion when an endovascular mesenteric artery revascularisation was scheduled and a consensus diagnosis of chronic mesenteric ischaemia was made by a multidisciplinary team of gastroenterologists, interventional radiologists, and vascular surgeons. Exclusion criteria were stenosis length of 25 mm or greater, stenosis caused by median arcuate ligament syndrome or vasculitis, contraindication for CT angiography, or previous target vessel revascularisation. Digital 1:1 block randomisation with block sizes of four or six and stratification by inclusion centre was used to allocate patients to undergo stenting with bare-metal stents or covered stents at the start of the procedure. Patients, physicians performing follow-up, investigators, and radiologists were masked to treatment allocation. Interventionalists performing the procedure were not masked. The primary study outcome was the primary patency of covered stents and bare-metal stents at 24 months of follow-up, evaluated in the modified intention-to-treat population, in which stents with missing data for the outcome were excluded. Loss of primary patency was defined as the performance of a re-intervention to preserve patency, or 75% or greater luminal surface area reduction of the target vessel. CT angiography was performed at 6 months, 12 months, and 24 months post intervention to assess patency. The study is registered with ClinicalTrials.gov (NCT02428582) and is complete. FINDINGS: Between April 6, 2015, and March 11, 2019, 158 eligible patients underwent mesenteric artery stenting procedures, of whom 94 patients (with 128 stents) provided consent and were included in the study. 47 patients (62 stents) were assigned to the covered stents group (median age 69·0 years [IQR 63·0-76·5], 28 [60%] female) and 47 patients (66 stents) were assigned to the bare-metal stents group (median age 70·0 years [63·5-76·5], 33 [70%] female). At 24 months, the primary patency of covered stents (42 [81%] of 52 stents) was superior to that of bare-metal stents (26 [49%] of 53; odds ratio [OR] 4·4 [95% CI 1·8-10·5]; p<0·0001). A procedure-related adverse event occurred in 17 (36%) of 47 patients in the covered stents group versus nine (19%) of 47 in the bare-metal stent group (OR 2·4 [95% CI 0·9-6·3]; p=0·065). Most adverse events were related to the access site, including haematoma (five [11%] in the covered stents group vs six [13%] in the bare-metal stents group), pseudoaneurysm (five [11%] vs two [4%]), radial artery thrombosis (one [2%] vs none), and intravascular closure device (none vs one [2%]). Six (13%) patients in the covered stent group versus one (2%) in the bare-metal stent group had procedure-related adverse events not related to the access site, including stent luxation (three [6%] vs none), major bleeding (two (4%) vs none), mesenteric artery perforation (one [2%] vs one [2%]), mesenteric artery dissection (one [2%] vs one [2%]), and death (one [2%] vs none). INTERPRETATION: The findings of this trial support the use of covered stents for mesenteric artery stenting in patients with chronic mesenteric ischaemia. FUNDING: Atrium Maquet Getinge Group.

Intestinal Ischemia - Etiology and Foundational Concepts.

Intestinal Ischemia: Etiology and Foundational ConceptsThe authors provide an overview of the intestinal anatomy and the pathophysiology and etiology of intestinal ischemia.

Correlation between white blood cell count and intestinal resection in patients with acute mesenteric vein thrombosis.

OBJECTIVE: Acute mesenteric vein thrombosis (AMVT) is an acute abdominal disease with onset, rapid progression, and extensive intestinal necrosis that requires immediate surgical resection. The purpose of this study was to determine the risk factors for nosocomial intestinal resection in patients with AMVT. METHODS: We retrospectively analysed 64 patients with AMVT diagnosed by CTA at the Affiliated Hospital of Kunming University of Science and Technology from January 2013 to December 2021. We compared patients who underwent intestinal resection (42 patients) with those who did not undergo intestinal resection (22 patients). The area under the ROC curve was evaluated, and a forest map was drawn. RESULTS: Among the 64 patients, 6 (9.38%) had a fever, 60 (93.75%) had abdominal pain, 9 (14.06%) had a history of diabetes, 8 (12.5%) had a history of deep vein thrombosis (DVT), and 25 (39.06%) had ascites suggested by B ultrasound or CT after admission. The mean age of all patients was 49.86 ± 16.25 years. The mean age of the patients in the enterectomy group was 47.71 ± 16.20 years. The mean age of the patients in the conservative treatment group (without enterectomy) was 53.95 ± 15.90 years. In the univariate analysis, there were statistically significant differences in leukocyte count (P = 0.003), neutrophil count (P = 0.001), AST (P = 0.048), total bilirubin (P = 0.047), fibrinogen (P = 0.022) and DD2 (P = 0.024) between the two groups. The multivariate logistic regression analysis showed that admission white blood cell count (OR = 1.153, 95% CI: 1.039-1.280, P = 0.007) was an independent risk factor for intestinal resection in patients with AMVT. The ROC curve showed that the white blood cell count (AUC = 0.759 95% CI: 0.620-0.897; P = 0.001; optimal threshold: 7.815; sensitivity: 0.881; specificity: 0.636) had good predictive value for emergency enterectomy for AMVT. CONCLUSIONS: Among patients with AMVT, patients with a higher white blood cell count at admission were more likely to have intestinal necrosis and require emergency enterectomy. This study is helpful for clinicians to accurately determine whether emergency intestinal resection is needed in patients with AMVT after admission, prevent further intestinal necrosis, and improve the prognosis of patients.

Predictive Factors of Intestinal Ischaemia in Adhesive Small Bowel Obstruction.

OBJECTIVE: To identify the predictive factors of intestinal ischaemia in adhesive small bowel obstruction (ASBO) and develop an intestinal ischaemia risk score. STUDY DESIGN: Observational study. Place and Duration of the Study: Department of General Surgery, Shandong Provincial Qianfoshan Hospital, Jinan, Shandong, China, from January 2017 to February 2022. METHODOLOGY: ASBO was determined by findings at laparotomy. The assessment of small bowel's viability was conducted through surgical inspection and subsequent histological examination of the surgical specimen. Univariate and multivariate analyses were conducted to ascertain the risk factors associated with intestinal ischaemia. RESULTS: In total, 79 patients were included. Factors entered into multivariate analysis associated with intestinal ischaemia were; rebound tenderness (odds ratio (OR): 7.8, 95% confidence interval (CI):1.7-35.3; p=0.008), procalcitonin (PCT) >0.5 ng/mL (OR: 11.7, 95% CI: 2.3-58.1; p=0.003), and reduced bowel wall enhancement on computerised tomography (CT) scan (OR: 12.2, 95% CI:2.4-61.5; p=0.003). Among patients with 0, 1, 2, and 3 factors, the rate of intestinal ischaemia increased from 0% to 49%, 72%, and 100%, respectively. According to the number of risk factors, the area under the receiver operating characteristic curve for the determination of intestinal ischaemia was 0.848 (95% CI: 0.764-0.932). CONCLUSION: Rebound tenderness, PCT levels >0.5 ng/mL, and reduced bowel wall enhancement are risk factors of intestinal ischemic injury that require surgery within the context of ASBO. These factors need to be closely monitored that could assist clinicians in avoiding unnecessary laparotomies and selecting patients eligible for surgery. KEY WORDS: Intestinal obstruction, Ischaemia, Adhesions.

[Indications and technique of open vascular surgical revascularization of visceral arteries in mesenteric ischemia]. / Indikation und Technik der offen-gefäßchirurgischen Revaskularisation der Viszeralarterien bei mesenterialer Ischämie.

Open revascularization for mesenteric ischemia has retained a significant value despite the increasing importance and use of endovascular techniques. Surgical procedures such as retrograde embolectomy, thromboendarterectomy and visceral bypass are indispensable components of the therapeutic armamentarium, particularly in cases of multisegmental vascular involvement, failure of previous endovascular treatment and concomitant presence of peritonitis, shock or multiorgan failure. In this context, preoperative multiphase computed tomography (CT) angiography is essential for the planning and outcome of visceral revascularization. This article summarizes the indications, technique, and results of the most important open surgical procedures.