Somatostatin Peptides Prevent Increased Human Colonic Epithelial Permeability Induced by Hypoxia.

Mesenteric ischemia increases gut permeability and bacterial translocation. In human colon, chemical hypoxia induced by 2,4-dinitrophenol (DNP) activates basolateral intermediate conductance K+ (IK) channels (designated KCa3.1 or KCNN4) and increases paracellular shunt conductance/permeability (GS), but whether this leads to increased macromolecule permeability is unclear. Somatostatin (SOM) inhibits IK channels and prevents hypoxia-induced increases in GS. Thus, we examined whether octreotide (OCT), a synthetic SOM analogue, prevents hypoxia-induced increases GS in human colon and hypoxia-induced increases in total epithelial conductance (GT) and permeability to FITC-dextran 4000 (FITC) in rat colon. The effects of serosal SOM and OCT on increases in GS induced by 100 µM DNP were compared in isolated human colon. The effects of OCT on DNP-induced increases in GT and transepithelial FITC movement were evaluated in isolated rat distal colon. GS in DNP-treated human colon was 52% greater than in controls (P = 0.003). GS was similar when 2 µM SOM was added after or before DNP treatment, in both cases being less (P <0.05) than with DNP alone. 0.2 µM OCT was equally effective preventing hypoxia-induced increases in GS, whether added after or before DNP treatment. In rat distal colon, DNP significantly increased GT by 18% (P = 0.016) and mucosa-to-serosa FITC movement by 43% (P = 0.01), and 0.2 µM OCT pre-treatment completely prevented these changes. We conclude that OCT prevents hypoxia-induced increases in paracellular/macromolecule permeability and speculate it may limit ischemia-induced gut hyperpermeability during abdominal surgery, thereby reducing bacterial/bacterial toxin translocation and sepsis.

Long-term value in open and endovascular repair of chronic mesenteric ischemia.

OBJECTIVE: Guidelines recommend open revascularization (OR) over endovascular revascularization (ER) for the treatment of chronic mesenteric ischemia (CMI) for younger, healthier patients. However, little is known about the long-term costs of these recommendations with respect to patients' overall life expectancy. This study investigated whether 5-year value differs between these treatment modalities. METHODS: Patient data were extracted from the Statewide Planning and Research Cooperative System, the New York statewide all-payor database containing demographics, diagnoses, treatments, and charges. The database was queried for patients with an International Classification of Diseases, ninth revision, code for CMI, with the specific exclusion of acute ischemia cases. A propensity score match was performed using the Charlson Comorbidity Index, age, sex, race, renal status, and pulmonary disease for the final cohort of patients. Multiple linear regression and mixed effects linear regression were used to determine factors associated with 5-year value, calculated as life-years/$100k in charges. Charges were gathered from the index admission and subsequent admissions for acute or CMI, mesenteric angiography, or follow-up reintervention. Kaplan-Meier estimation was performed for survival and reintervention-free survival. RESULTS: From 2000 to 2014, 875 patients underwent intervention for CMI. Of those meeting inclusion criteria, 209 (28.1%) underwent OR and 535 (71.9%) ER. After propensity score matching (n = 209 in each group), the ER group showed higher value at 5 years after the procedure (8.04 ± 11.42 life-years/$100k charges vs 4.89 ± 5.28 life-years/$100k charges; P < .01). More patients underwent reintervention in the ER group (37 patients vs 17 patients; P < .01), with 55 reinterventions in the ER group and 19 in the OR group (P < .01). Multiple linear regression analysis showed that age, congestive heart failure, dysrhythmia, cancer, and days spent in the intensive care unit were negatively associated with value at 5 years, whereas ER was positively associated. Survival was 59.6 ± 3.76% vs 62.3% ± 3.49% at 5 years (P = .91), and reintervention-free survival was 43.7 ± 3.86% vs 58.1 ± 3.53% (P = .04), for ER and OR respectively. CONCLUSIONS: Despite increased reinterventions and lower reintervention-free survival, the value for patients with CMI was higher in those who underwent ER in the largest propensity score-matched cohort to date looking at long-term value. Factors negatively associated with value were OR, age, days in intensive care, congestive heart failure, dysrhythmia, and cancer. In patients with amenable anatomy, ER is validated as the first-choice treatment for CMI based on the superior procedural value.

A decade's experience with retrograde open mesenteric stenting for acute mesenteric ischemia.

OBJECTIVE: Retrograde open mesenteric stenting (ROMS) is an alternative to mesenteric bypass in patients with acute mesenteric ischemia (AMI) with variable reported 30-day mortality rates. Large studies evaluating patient outcomes following ROMS are scarce. Our study aims to assess the results of this approach among patients presenting with AMI. METHODS: We reviewed all the patients with AMI who were treated with ROMS (2011-2022). Patient demographics, presentation, operative details, and outcomes were analyzed. Primary end points were in-hospital, 30-day, and 1-year mortality. Kaplan-Meier estimate for 1-year mortality and primary patency loss were generated. Secondary end points included postoperative 30-day complications. RESULTS: Between 2011 and 2022, ROMS was attempted on a total of 42 patients. The median age was 70 ± 15 years and the majority of patients were female. Pain out of proportion to the physical examination was the most common presenting symptom (n = 18, 42.9%) followed by peritonitis (n = 14, 33.4%). All patients underwent preoperative intravenous contrast computed tomography imaging. In situ thrombosis was identified as the etiology of AMI in 36 patients (85.7%). Technical success was achieved in 40 patients (95.2%). Conventional, non-hybrid operating rooms were used for the majority of cases. Revascularization of all 40 patients involved angioplasty and stenting of superior mesenteric artery. A single stent was placed in 35 patients (87.5%) and the reminder had more than one stent. Eighty percent of patients required bowel resection. A second-look laparotomy was required in 34 patients (85.0%). The mean operative time, including both the general surgery and vascular surgery portions of the index procedure, was 192 ± 57 minutes. Sepsis was the most common complication observed within 30 days, occurring in 8 patients (20.0%). In terms of mortality, 13 patients (32.5%) died during their index hospitalization, and 9 died (22.5%) within 30 days. On Kaplan-Meier analysis, the 1-year overall patient survival rate was 58.6%, and the primary patency rate for stents was 51.4%. CONCLUSIONS: ROMS has an excellent technical success rate in management of AMI with lower than traditionally reported mortality rates for AMI. The dual benefits of rapid revascularization and bowel evaluation should make this surgical modality an alternative approach for treatment of AMI.

Comparative outcomes of open mesenteric bypass after a failed endovascular or open mesenteric revascularization for chronic mesenteric ischemia.

INTRODUCTION: Clinical practice guidelines have recommended an endovascular-first approach (ENDO) for the management of patients with chronic mesenteric ischemia (CMI), whereas an open mesenteric bypass (OMB) is proposed for subjects deemed to be poor ENDO candidates. However, the impact of a previous failed endovascular or open mesenteric reconstruction on a subsequent OMB is unknown. Accordingly, this study was designed to examine the results of a remedial OMB (R-OMB) after a failed ENDO or a primary OMB (P-OMB) for patients with recurrent CMI. METHODS: All patients who underwent an OMB from 2002 to 2022 at the University of Florida were reviewed. Outcomes after an R-OMB (ie, history of a failed ENDO or P-OMB) and P-OMB were compared. The primary end point was 30-day mortality, whereas secondary outcomes included complications, reintervention, and survival. The Kaplan-Meier methodology was used to estimate freedom from reintervention and all-cause mortality, whereas multivariable Cox proportional hazards modeling identified predictors of death. RESULTS: A total of 145 OMB procedures (R-OMB, n = 48 [33%]; P-OMB, n = 97 [67%]) were analyzed. A majority of R-OMB operations were performed for a failed stent (prior ENDO, n = 39 [81%]; prior OMB, n = 9 [19%]). R-OMB patients were generally younger (66 ± 9 years vs P-OMB, 69 ± 11 years; P = .09) and had lower incidence of smoking exposure (29% vs P-OMB, 48%; P = .07); however, there were no other differences in demographics or comorbidities. R-OMB was associated with less intraoperative transfusion (0.6 units vs P-OMB, 1.4 units; P = .01), but there were no differences in conduit choice or bypass configuration.The overall 30-day mortality and complication rates were 7% (n = 10/145) and 53% (n = 77/145), respectively, with no difference between the groups. Notably, R-OMB had decreased cardiac (6% vs P-OMB, 21%; P < .01) and bleeding complication rates (2% vs P-OMB, 15%; P = .01). The freedom from reintervention (1 and 5 years: R-OMB: 95% ± 4%, 83% ± 9% vs P-OMB: 97% ± 2%, 93% ± 5%, respectively; log-rank P = .21) and survival (1 and 5 years: R-OMB: 82% ± 6%, 68% ± 9% vs P-OMB: 84% ± 4%, 66% ± 7%; P = .91) were similar. Independent predictors of all-cause mortality included new postoperative hemodialysis requirement (hazard ratio [HR], 7.4, 95% confidence interval [CI], 3.1-17.3; P < .001), pulmonary (HR, 2.7, 95% CI, 1.4-5.3; P = .004) and cardiac (HR, 2.4, 95% CI, 1.1-5.1; P = .04) complications, and female sex (HR, 2.1, 95% CI, 1.03-4.8; P = .04). Notably, R-OMB was not a predictor of death. CONCLUSIONS: The perioperative and longer-term outcomes for a remedial OMB after a failed intraluminal stent or previous open bypass appear to be comparable to a P-OMB. These findings support the recently updated clinical practice guideline recommendations for an endovascular-first approach to treating recurrent CMI due to the significant perioperative complication risk of OMB. However, among the subset of patients deemed ineligible for endoluminal reconstruction after failed mesenteric revascularization, R-OMB results appear to be acceptable and highlight the utility of this strategy in selected patients.

Natural history of superior mesenteric artery in-stent restenosis.

OBJECTIVE: Superior mesenteric artery (SMA) stenting is the preferred approach for patients with symptomatic SMA-associated chronic mesenteric ischemia (CMI). The durability of this modality is impacted by in-stent restenosis (ISR). Duplex ultrasound (DUS) and computed tomographic angiography (CTA)-measured ISR may be weakly correlated and not uniformly associated with recurrence of presenting symptoms. This study aims to analyze the association between the degree of ISR for patients with CMI and to develop a predictive model for symptom recurrence. METHODS: Single center, retrospective study included all patients with CMI with SMA stents from the period of 2003 to 2020. Follow-up period analysis included patients' symptoms recurrence, DUS, CTA, and angiography. A receiver operating characteristic (ROC) analysis was used to evaluate whether peak systolic velocity (PSV) was predictive of symptom recurrence. A subgroup analysis of patients (asymptomatic and symptomatic) with SMA ISR was identified; restenosis defined by DUS with peak systolic velocity (PSV) ≥350. RESULTS: The study included 186 patients with the ROC analysis obtained from 503 postoperative visits. PSV was not a predictor of symptoms return with area under the curve (AUC) = 0.49 (95% confidence interval [CI], 0.40-0.57). Agreement analysis between imaging modalities showed higher agreement between CTA and angiogram (AUC, 0.769; 95% CI, 0.688-0.849) vs CTA and DUS (AUC, 0.650; 95% CI, 0.589-0.711). The subgroup analysis of patients with ISR included 99 patients (asymptomatic n = 67; symptomatic n = 32). There was no statistical difference between median time (months) to ISR between both groups: 4.5 (asymptomatic group) and 7.6 (symptomatic group). The use of preoperative antiplatelet (86% vs 65%; P = .015) and P2Y12 receptor blockers (36% vs 13%; P = .016) was more prevalent in the asymptomatic group. There was no difference between the type or number of stents placed, stent diameter, or concomitant celiac artery intervention between both groups. CONCLUSIONS: The natural history of SMA and multimodality defined ISR in CMI has not previously been described. Elevated PSV was a poor predictor of symptoms recurrence. Both asymptomatic and symptomatic patients with ISR did not differ in type of stent placed, time to ISR, or involvement of celiac artery. Antiplatelet use pre- and postoperatively appears protective against symptoms recurrence. Our findings underscore the need for long-term surveillance integrating clinical evaluation and multimodality imaging when indicated.

Aortic endarterectomy in patients with severe multivessel paravisceral and aortoiliac occlusive disease.

OBJECTIVE: Aortic endarterectomy (AE), once a treatment of choice for aortoiliac occlusive disease, is now rarely performed in favor of endovascular procedures or open aortobifemoral bypass. However, in select patients with paravisceral or aortoiliac occlusive disease, AE remains a viable alternative for revascularization, either as a primary procedure or after prior interventions have failed. Here, we evaluated outcomes for an extended series of patients undergoing paravisceral or aortoiliac endarterectomy, demonstrating that these procedures can be an excellent alternative with acceptable morbidity and mortality in properly selected patients. METHODS: A single institution retrospective review of 20 patients who underwent AE from 2017 to 2023 was performed. RESULTS: Five patients (25%) underwent paravisceral endarterectomy and 15 (75%) underwent aortoiliac endarterectomy. There were no perioperative mortalities. One paravisceral patient died 3 months postoperatively from complications of pneumonia. Three patients in the paravisceral group required reinterventions; one acutely due to thrombosis of the superior mesenteric artery (SMA) requiring extension of the endarterectomy and patch angioplasty on postoperative day 0, one due to stenosis at the distal edge of the endarterectomy 1 month postoperatively, successfully treated with SMA stenting, and one at 10-month follow-up due to SMA stenosis at the distal aspect of the endarterectomy, also successfully treated with SMA stenting. With these reinterventions, the 1-year primary patency in the paravisceral group was 40%, primary-assisted patency was 80%, and secondary patency was 100%. In the aortoiliac group, 1-year primary, primary-assisted, and secondary patency were 91%, 91%, and 100%, respectively. One patient developed iliac thrombosis 10 days postoperatively owing to an intimal flap distal to the endarterectomy site. She and one other patient, a young man with an undefined hypercoagulable disorder, ultimately required neoaortoiliac reconstructions at 18 and 32 months postoperatively, respectively (the latter in the setting of stopping anticoagulation). The remaining 13 patients experienced no complications. All patients had rapid resolution of clinical symptoms, and median postoperative ankle-brachial indexes of 1.06 on the right and 1.00 on the left, representing a median improvement from preoperative ankle-brachial indexes of +0.59 on the right and +0.56 on the left (P < .01 and P < .01). CONCLUSIONS: In this series of 20 patients undergoing paravisceral and infrarenal aortoiliac endarterectomy, AE was associated with no perioperative mortality, relatively low and manageable morbidity, and excellent clinical outcomes in patients with both paravisceral and aortoiliac occlusive disease. SMA-related early reintervention was not uncommon in the paravisceral group, and attention should be given particularly to the distal endarterectomy site. AE remains a viable treatment for severe multivessel paravisceral or aortoiliac occlusive disease isolated to the aorta and common iliac arteries in select patients.

Endovascular revascularization vs open surgical revascularization as the first strategy for arterial acute mesenteric ischemia: A systematic review and meta-analysis.

OBJECTIVE: This paired meta-analysis aimed to compare the mortality and morbidity of endovascular revascularization (EVR) and open surgical revascularization (OSR) as the first strategy for arterial acute mesenteric ischemia (AMI). METHODS: This systematic review and meta-analysis were performed in accordance with the PRISMA statement. A systematic search strategy was performed to identify eligible studies using the following databases: PubMed, Embase, and Cochrane Library database from inception to December 31, 2023, with restriction to the English language. The end search date was January 2, 2024. The primary outcome was short-term mortality. Secondary outcomes included bowel resection, second-look laparotomy, and short bowel syndrome. The counterenhanced funnel plot and the Peters' test were used to assess bias. Outcomes were reported as odds ratio (OR) with a 95% confidence interval (CI) using the Mantel-Haenszel method. The GRADE classification was used to estimate the certainty of evidence. RESULTS: A total of 11 studies (1141 patients) comparing EVR vs OSR for arterial AMI were identified and analyzed. The mean patient age was 61.9 to 73.6 years and 45.1% of the patients were male. Compared with OSR, EVR as the first treatment may not decrease short-term mortality (OR, 0.79; 95% CI, 0.50-1.25; P = .31; very low certainty) and second-look laparotomy (OR, 1.00; 95% CI, 0.30-3.36; P = .99; very low certainty). However, EVR may be associated with decreased bowel resection (OR, 0.42; 95% CI, 0.20-0.88; P = .022; very low certainty) and short bowel syndrome (OR, 0.39; 95% CI, 0.21-0.75; P = .005; very low certainty). The metaregression revealed that the mortality regarding EVR vs OSR was not impacted significantly by thrombotic etiology (-0.002; 95% CI, -0.027 to 0.022; P = .85), whereas it was impacted significantly by publication year (0.076; 95% CI, 0.069-0.145; P = .031). CONCLUSIONS: Compared with OSR, EVR as the first treatment for arterial AMI may not decrease short-term mortality or second-look laparotomy. Future multicenter randomized controlled trials are needed urgently to confirm these results.

Association between PAI-1 4G/5G genotype and residual thrombus in acute mesenteric venous thrombosis.

OBJECTIVE: Plasminogen activator inhibitor-1 (PAI-1) is the most important inhibitor of plasminogen activator. The functional 4G/5G polymorphism of the gene coding for PAI-1 may affect PAI-1 plasmatic activity, influencing the imbalance between coagulation and fibrinolysis cascades. In this study, we investigated the association between the PAI-1 4G/5G genotype and the development and residual thrombus of acute primary mesenteric venous thrombosis (MVT). METHODS: The clinical data of 34 patients who underwent acute primary MVT were retrospectively reviewed. Fluorescence in situ hybridization was used to determine if patients had the 4G/5G polymorphism in the promoter of the PAI-1 gene. Patients were stratified according to the genotype of PAI-1. RESULTS: 11 patients (32.3%) were homozygous for the 4G genotype, 23 patients (67.6%) were non-homozygous for the 4G genotype (5G/5G). The extent of thrombosis was not correlated with the PAI-4G/5G polymorphism. After a mean follow-up of 16.6 ± 10.4 months, the 4G/4G genotype had a significantly larger thrombus burden (p < 0.05). 54% of patients in the 4G/4G genotype group had no lessening in the degree of mesenteric venous thrombosis, significantly higher than other patients (4G/5G + 5G/5G genotypes) (p < 0.05). CONCLUSION: The PAI-1 4G/4G predicts residual thrombus of mesenteric veins after the acute phase.

Impact of hyperoxia on the gut during critical illnesses.

Molecular oxygen is typically delivered to patients via oxygen inhalation or extracorporeal membrane oxygenation (ECMO), potentially resulting in systemic hyperoxia from liberal oxygen inhalation or localized hyperoxia in the lower body from peripheral venoarterial (VA) ECMO. Consequently, this exposes the gastrointestinal tract to excessive oxygen levels. Hyperoxia can trigger organ damage due to the overproduction of reactive oxygen species and is associated with increased mortality. The gut and gut microbiome play pivotal roles in critical illnesses and even small variations in oxygen levels can have a dramatic influence on the physiology and ecology of gut microbes. Here, we reviewed the emerging preclinical evidence which highlights how excessive inhaled oxygen can provoke diffuse villous damage, barrier dysfunction in the gut, and gut dysbiosis. The hallmark of this dysbiosis includes the expansion of oxygen-tolerant pathogens (e.g., Enterobacteriaceae) and the depletion of beneficial oxygen-intolerant microbes (e.g., Muribaculaceae). Furthermore, we discussed potential impact of oxygen on the gut in various underlying critical illnesses involving inspiratory oxygen and peripheral VA-ECMO. Currently, the available findings in this area are somewhat controversial, and a consensus has not yet to be reached. It appears that targeting near-physiological oxygenation levels may offer a means to avoid hyperoxia-induced gut injury and hypoxia-induced mesenteric ischemia. However, the optimal oxygenation target may vary depending on special clinical conditions, including acute hypoxia in adults and neonates, as well as particular patients undergoing gastrointestinal surgery or VA-ECMO support. Last, we outlined the current challenges and the need for future studies in this area. Insights into this vital ongoing research can assist clinicians in optimizing oxygenation for critically ill patients.

The open abdomen in mesenteric ischemia: A tool for patients undergoing revascularization.

BACKGROUND: We examined outcomes in Acute Mesenteric Ischemia (AMI) with the hypothesis that Open Abdomen (OA) is associated with decreased mortality. METHODS: We performed a cohort study reviewing NSQIP emergency laparotomy patients, 2016-2020, with a postoperative diagnosis of mesenteric ischemia. OA was defined using flags for patients without fascial closure. Logistic regression was used with outcomes of 30-day mortality and several secondary outcomes. RESULTS: Out of 5514 cases, 4624 (83.9%) underwent resection and 387 (7.0%) underwent revascularization. The OA rate was 32.6%. 10.8% of patients who were closed required reoperation. After adjustment for demographics, transfer status, comorbidities, preoperative variables including creatinine, white blood cell count, and anemia, as well as operative time, OA was associated with OR 1.58 for mortality (95% CI [1.38, 1.81], p < 0.001). Among revascularizations, there was no such association (p = 0.528). OA was associated with ventilator support >48 h (OR 4.04, 95% CI [3.55, 4.62], and p < 0.001). CONCLUSION: OA in AMI was associated with increased mortality and prolonged ventilation. This is not so in revascularization patients, and 1 in 10 patients who underwent primary closure required reoperation. OA should be considered in specific cases of AMI. LEVEL OF EVIDENCE: Retrospective cohort, Level III.

Preoperative risk factors for 90-day postoperative mortality outcome in patients with non-occlusive mesenteric ischemia.

PURPOSE: The mortality rate for non-occlusive mesenteric ischemia remains high even after patients survive the acute postoperative period with tremendous treatment efforts, including emergency surgery, which is challenging. The aim of this study was to explore the preoperative risk factors for 90-day postoperative mortality in patients with non-occlusive mesenteric ischemia. METHODS: This single-center, retrospective cohort study included patients diagnosed with non-occlusive mesenteric ischemia who underwent emergency surgery between August 2014 and January 2023. All patients were divided into survival-to-discharge and mortality outcome groups at the 90-day postoperative follow-up. Preoperative factors, including comorbidities, preoperative status of vital signs and consciousness, blood gas analysis, blood test results, and computed tomography, were compared between the two groups. RESULTS: Twenty patients were eligible, and 90-day mortality was observed in 10 patients (50%). The mortality outcome group had significantly lower HCO3- (20.9 vs. 14.6, p = 0.006) and higher lactate (4.4 vs. 9.4, p = 0.023) levels than did the survival outcome group. The median postoperative time to death was 19 [2-69] days, and five patients (50%) died after postoperative day 30, mainly because hemodialysis was discontinued because of hemodynamic instability in patients requiring hemodialysis. CONCLUSION: Low preoperative HCO3- and high lactate levels may be preoperative risk factors for 90-day postoperative mortality in patients with non-occlusive mesenteric ischemia. However, patients on hemodialysis die from discontinuing hemodialysis even after surviving the acute postoperative phase. Therefore, indications for emergency surgery in patients with risk factors for postoperative mortality should be carefully determined.

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.

Revascularization of superior mesenteric artery occlusion via the arc of Buhler: A case report and literature review.

BACKGROUND: To report revascularization of a superior mesenteric artery (SMA) ostial occlusion via the Arc of Buhler. CASE REPORT: A 62-year-old female presented with 2 months of recurrent abdominal distension and postprandial pain. Computed tomography angiography (CTA) revealed ostial occlusion of the SMA with distal perfusion via the Arc of Buhler (connecting the celiac trunk and SMA). Conventional endovascular techniques failed. A 0.014 guidewire was passed retrograde through the occlusion via the Arc of Buhler. The guidewire was captured from the femoral sheath and balloon angioplasty with stent placement was performed. The patient had complete symptom resolution post-procedure. CONCLUSIONS: Retrograde revascularization via the Arc of Buhler is an effective method for treating the initial segment occlusion of the SMA.

Treatment outcomes in non-occlusive mesenteric ischemia and post-treatment return to social activities.

PURPOSE: To investigate the treatment outcomes of patients with non-occlusive mesenteric ischemia (NOMI) at our institution, we focused on their post-treatment return to social activities. METHODS: This study included patients with suspected NOMI who were referred to our department between 2011 and 2023. In-hospital mortality was also investigated as a prognostic factor. The Glasgow-Pittsburgh Outcome Categories (GPOC) score was used to evaluate the return to social activities. The relationship between in-hospital mortality and GPOC scores and patient background and treatment factors was examined. RESULTS: Eighty-two patients were included in the study. Among them, 54 (65.9%) died during hospitalization. Only 9 patients (11%) returned to their social activities. In the multivariate analysis, non-surgical management was found to be the only independent factor for in-hospital mortality. Positive portal venous gas on computed tomography, no open abdomen, no pre-onset catecholamine administration, platelet count < 100,000/µL, lactate level < 5 mmol/L, APTT < 46 s, and Sequential Organ Failure Assessment score < 11 were factors significantly associated with an increased likelihood of return to social activities. CONCLUSION: This is the first study to assess the post-treatment return to social activities among patients with NOMI. Our findings highlight the concerning reality that survivors may face prolonged dependence on medical care.

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

BACKGROUND: Acute mesenteric ischemia is a rare but lethal disease. Acute occlusive mesenteric ischemia consists of mesenteric artery embolism, mesenteric artery thrombosis, and mesenteric vein thrombosis. This study aimed to investigate the factors that may affect the outcome of acute occlusive mesenteric ischemia. METHODS: Data from acute occlusive mesenteric ischemia patients admitted between May 2016 and May 2022 were reviewed retrospectively. Patients were divided into 2 groups according to whether complications(Clavien‒Dindo ≥ 2) occurred within 6 months of the first admission. Demographics, symptoms, signs, laboratory results, computed tomography angiography features, management and outcomes were analyzed. RESULTS: 59 patients were enrolled in this study. Complications(Clavien‒Dindo ≥ 2) occurred within 6 months of the first admission in 17 patients. Transmural intestinal necrosis, peritonitis, white blood cell count, percentage of neutrophils, percentage of lymphocytes, neutrophil-to-lymphocyte ratio, lactate dehydrogenase, creatine kinase isoenzyme, cardiac troponin I, laparoscopic exploration rate, open embolectomy rate, enterostomy rate, length of necrotic small bowel, length of healthy small bowel, surgical time and intraoperative blood loss differed significantly between groups. Creatine kinase isoenzyme (OR = 1.415, 95% CI: 1.060-1.888) and surgical time (OR = 1.014, 95% CI: 1.001-1.026) were independent risk factors associated with complications(Clavien‒Dindo ≥ 2). CONCLUSIONS: Our analysis suggests that acute occlusive mesenteric ischemia patients with a creatine kinase isoenzyme level greater than 2.22 ng/mL or a surgical time longer than 156 min are more likely to experience complications'(Clavien‒Dindo ≥ 2) occurrence within 6 months of the first admission.

Exploring D-Lactate as a Biomarker for Acute Intestinal Necrosis in 2958 Patients: A Prospective Cross-Sectional Study.

BACKGROUND: Timely diagnosis of acute intestinal necrosis (AIN) is lifesaving, but challenging due to unclear clinical presentation. D-lactate has been proposed as an AIN biomarker. OBJECTIVES: We aimed to test the diagnostic performance in a clinical setting. METHODS: We performed a cross-sectional prospective study, including all adult patients with acute referral to a single tertiary gastrointestinal surgical department during 2015-2016 and supplemented by enrollment of high-risk in-hospital patients suspected of having AIN during 2016-2019. AIN was verified intraoperatively, and D-lactate was analyzed using an automatic spectrophotometric set-up. A D-lactate cut-off for AIN was estimated using the receiver operating characteristic curve. The performance according to patient subgroups was estimated using the area under the receiver operating characteristic curve (AUC). Given the exploratory nature of this study, a formal power calculation was not feasible. RESULTS: Forty-four AIN patients and 2914 controls were enrolled. The D-lactate cut-off was found to be 0.0925 mM. Due to lipemic interference, D-lactate could not be quantified in half of the patients, leaving 23 AIN patients and 1456 controls for analysis. The AUC for the diagnosis of AIN by D-lactate was 0.588 (95% confidence interval 0.475-0.712), with a sensitivity of 0.261 and specificity of 0.892. Analysis of high-risk patients showed similar results (AUC 0.579; 95% confidence interval 0.422-0.736). CONCLUSION: D-lactate showed low sensitivity for AIN in both average-risk and high-risk patients. Moreover, lipemic interference precluded valid spectrophotometric assessment of D-lactate in half of the patients, further disqualifying the clinical utility of D-lactate as a diagnostic marker for AIN.

Open revascularization for chronic mesenteric ischemia in the endovascular era: a quaternary-center experience and management algorithm.

Background: Chronic mesenteric ischemia (CMI) is a debilitating disease with a heavy burden on quality of life. Stenting of the superior mesenteric artery (SMA) is the first option for treatment, but there is a lack of consensus defining precise indications for open revascularization (OR). Objectives: To describe a series of 4 patients with CMI treated with OR and to present an algorithm for the management of this condition. Methods: Three patients presented with typical intestinal angina and weight loss. One patient was subjected to prophylactic revascularization during open abdominal aortic aneurysm repair. Surgical techniques included: 1) Bypass from the infrarenal aorta to the SMA; 2) Bypass from an aorto-bifemoral polyester graft to the SMA; 3) Bypass from the right iliac artery to the SMA; 4) Bypass from the right graft limb of an aorto-biiliac polyester graft to the median colic artery at Riolan's arcade. PTFE was used in all surgeries. All grafts were placed in a retrograde configuration, tunneled under the left renal vein, making a smooth C-loop. A treatment algorithm was constructed based on the institution's experience and a review of recent literature. Results: All patients demonstrated resolution of symptoms and recovery of body weight. All grafts are patent after mean follow-up of two years. Conclusions: Open revascularization using the C-loop configuration is a valuable technique for CMI and may be considered in selected cases. The algorithm constructed may help decision planning in other quaternary centers.

Contexto: A isquemia mesentérica crônica (IMC) é uma doença debilitante, com grave impacto na qualidade de vida. A literatura recomenda a angioplastia com stent da artéria mesentérica superior (AMS) como primeira opção de tratamento, mas há falta de consenso que defina indicações precisas para a revascularização aberta. Objetivos: Descrever uma série de quatro pacientes com IMC, tratados com revascularização aberta, e apresentar um algoritmo para o manejo dessa condição. Métodos: Três pacientes apresentaram angina intestinal típica e perda ponderal. Uma paciente foi submetida a reparo aberto de aneurisma da aorta abdominal e apresentava obstrução da AMS, que foi revascularizada profilaticamente. As técnicas cirúrgicas incluíram: 1) enxerto entre a aorta infrarrenal e a AMS; 2) enxerto entre o dácron utilizado em um enxerto aortobifemoral e a AMS; 3) enxerto entre a artéria ilíaca comum direita e a AMS; e 4) enxerto entre o ramo direito do dácron utilizado em um enxerto aorto-biilíaco e a artéria cólica média (ao nível da arcada de Riolan). Todos os enxertos foram feitos utilizando politetrafluoretileno em uma configuração retrógrada, tunelizados abaixo da veia renal esquerda, fazendo uma alça em C. Resultados: Todos os pacientes demonstraram resolução dos sintomas e ganho ponderal. Todos os enxertos se mantiveram pérvios durante um seguimento médio de 2 anos. Conclusões: A revascularização aberta para IMC utilizando-se a alça em C é uma técnica valiosa e pode ser considerada em pacientes selecionados. O algoritmo proposto pode auxiliar na decisão terapêutica em centros quaternários.

[Modern biochemical markers of acute mesenteric ischemia]. / Sovremennye biokhimicheskie markery ostroi mezenterial'noi ishemii.

OBJECTIVE: To analyze modern literature data on biochemical markers of critical mesenteric ischemia. MATERIAL AND METHODS: We analyzed the most promising, highly specific and sensitive biochemical markers of total and segmental intestinal damage following acute mesenteric ischemia. Analysis included domestic and foreign literature data between 2015 and 2023. RESULTS: We identified the most easy-to-use for any hospitals biochemical markers with at least 90% sensitivity and specificity for further practical research. CONCLUSION: Further prospective research will provide a new step in solving the problem of timely diagnosis of acute mesenteric circulatory disorders.

Long-term outcome after implementation of endovascular-first strategy to treat acute mesenteric ischemia.

OBJECTIVE: To evaluate the rationale of an aggressive endovascular-first strategy to treat elderly patients with acute mesenteric ischemia (AMI) by studying long-term survival, readmissions, and patients' discharge to home vs nursing facility a decade after an episode of AMI. METHODS: The retrospective study cohort included 66 consecutive patients (all-comers) treated for arterial occlusive AMI between 2009 and 2013. Endovascular revascularization (EVR) was attempted in 50 patients (EVR+), whereas 16 patients were treated without attempted revascularization (EVR-). All patients were followed until death or September 2022. Studied outcomes included discharge status, long-term survival and cause of death and readmissions related to AMI. RESULTS: The mean age of all 66 patients was 78 ± 10 years: 79 ± 9 years in the EVR+ group and 76 ± 12 years in the EVR- group. EVR was technically successful in 44 patients (88%); three patients underwent subsequent open revascularization after EVR failure. One-third required bowel resection after EVR. The 30-day mortality for all patients was 44%; 32% in the EVR+ group and 81% in the EVR- group. Only two survivors were permanently institutionalized, whereas all others were discharged to the same place they lived prior to the AMI episode. There were four AMI-related readmissions during the follow-up; all were in the EVR+ group. Two patients underwent reinterventions for recurrent AMI. One-year survival was 52% for EVR+ and 19% for EVR- patients. Five-year survival rates were 18% and 13%, respectively. The causes of deaths were mesenteric ischemia in 22, other cardiovascular event in 21, and non-cardiovascular cause in 19 patients. Four patients were alive at the end of the follow-up. CONCLUSIONS: In this unselected elderly population with AMI, the aggressive strategy to attempt EVR resulted in a high revascularization rate and favorable outcomes. The high proportion of patients returning to their prior living status and low readmission rate after survival from AMI encourages active treatment of high-functioning elderly patients.

Management of patients with chronic mesenteric ischemia across three consecutive eras.

BACKGROUND: Endovascular intervention (EI) is the most commonly used modality for chronic mesenteric ischemia (CMI). Since the inception of this technique, numerous publications have reported the associated clinical outcomes. However, no publication has reported the comparative outcomes over a period of time in which both the stent platform and adjunctive medical therapy have evolved. This study aims to assess the impact of the concomitant evolution of both the endovascular approach and optimal guideline-directed medical therapy (GDMT) on CMI outcomes over three consecutive time eras. METHODS: A retrospective review at a quaternary center from January 2003 to August 2020 was performed to identify patients who underwent EIs for CMI. The patients were divided into three groups based on the date of intervention: early (2003-2009), mid (2010-2014), and late (2015-2020). At least one angioplasty/stent was performed for the superior mesenteric artery (SMA) and/or celiac artery. The patients' short- and mid-term outcomes were compared between the groups. Univariable and multivariable Cox proportional hazard models were also conducted to evaluate the clinical predictors for primary patency loss in SMA only subgroup. RESULTS: A total of 278 patients were included (early, 74; mid, 95; late, 109). The overall mean age was 71 years, and 70% were females. High technical success (early, 98.6%; mid, 100%; late, 100%; P = .27) and immediate resolution of symptoms (early, 86.3%; mid, 93.7%; late, 90.8%; P = .27) were noted over the three eras. In both the celiac artery and SMA cohorts, the use of bare metal stents (BMS) declined over time (early, 99.0%; mid, 90.3%; late, 65.5%; P < .001) with a proportionate increase in covered stents (CS) (early, 0.99%; mid, 9.7%; late, 28.9%; P < .001). The use of postoperative antiplatelet and statins has increased over time (early, 89.2%; mid, 97.9%; late, 99.1%; P = .003) and (early, 47%; mid, 68%; late, 81%; P = .001), respectively. In the SMA stent-only cohort, no significant differences were noted in primary patency rates between BMS and CS (hazard ratio, 0.95; 95% confidence interval, 0.26-2.87; P = .94). High-intensity preoperative statins were associated with fewer primary patency loss events compared to none/low- or moderate-intensity statins (hazard ratio, 0.30; 95% confidence interval, 0.11-0.72; P = .014). CONCLUSIONS: Consistent outcomes were observed for CMI EIs across three consecutive eras. In the SMA stent-only cohort, no statistically significant difference in early primary patency was noted for CS and BMS, making the use of CS at additional cost controversial and possibly not cost effective. Notably, the preoperative high-intensity statins were associated with improved SMA primary patency. These findings demonstrate the importance of guideline-directed medical therapy as an essential adjunct to EI in the treatment of CMI.