Open Abdomen Improves Survival in Patients With Peritonitis Secondary to Acute Superior Mesenteric Artery Occlusion

Management of acute mesenteric ischaemia in adult patients: a systematic review and meta-analysis

BACKGROUND

Guidance on managing acute mesenteric ischaemia (AMI) is largely based on expert opinion and retrospective studies pooling different subtypes of AMI. In clinical practice, management strategy is often selected based on the patient's severity of illness, whereas randomized controlled trials or even adjusted analyses comparing different strategies are rarely available. We aimed to perform a systematic review and meta-analysis on the effect of different management options when adjusted for the baseline severity of illness.

METHODS

A literature search was performed in PubMed, the Cochrane Library, Web of Science and Scopus. Studies recruiting patients after the year 2000, assessing at least 10 adult patients with reliably confirmed AMI, and comparing different management approaches were considered for inclusion. Thirteen study questions on different management strategies in different subtypes of AMI were formulated a priori. We included studies reporting results of adjusted analyses or reporting any variables reflecting the severity of illness in both study groups under comparison.

RESULTS

A total of 3324 publications were identified, 321 were selected for full-text review and 31 included in the review and analysis. Most of the studies comparing different management strategies of AMI did not report the severity of illness in the groups under comparison. Any variable that could be considered to reflect the severity of illness was reported in 26 studies. The available data only allowed one meta-regression analysis comparing initial endovascular revascularization versus open surgery in arterial occlusive AMI, including four studies that reported white blood cell count and lactate. The results indicate that the significant advantage of the endovascular approach suggested in the crude analysis may be abolished when adjusting for the severity of the illness. Narrative summaries and raw data are presented for other research questions.

CONCLUSIONS

The severity of illness plays an important role in the selection of management strategy and largely determines the outcome of any treatment, yet is generally not considered in available studies assessing the management of AMI. There is a major gap in the literature precluding appropriate analyses on treatment effects. Future studies should report subtypes of AMI and the severity of illness for each group.

STUDY REGISTRATION

PROSPERO CRD42024568497, date of registration: July 20th, 2024.

Advancements in Revascularization Strategies for Acute Mesenteric Ischemia: A Comprehensive Review

Even with modern advancements in the management of acute mesenteric ischemia over the past decade, morbidity and mortality remain high, and the best primary treatment modality is still debated amongst interventionalists. Traditionally, interventionalists have favored an open surgical approach but are now trending for endovascular interventions due to apparent reduced mortality and complications. Newer studies suggest hybrid approaches, and intestinal stroke centers may be superior to either strategy alone. This narrative review will explore the natural history of acute mesenteric ischemia with the aim of increasing interventionalist awareness of modern advancements in revascularization strategies for this devastating disease.

Neutrophil extracellular traps aggravate intestinal epithelial necroptosis in ischaemia-reperfusion by regulating TLR4/RIPK3/FUNDC1-required mitophagy

Neutrophil extracellular trap (NET) has been confirmed to be related to gut barrier injury during intestinal ischaemia-reperfusion (II/R). However, the specific molecular regulatory mechanism of NETs in II/R-induced intestinal barrier damage has yet to be fully elucidated. Here, we reported increased NETs infiltration accompanied by elevated inflammatory cytokines, cellular necroptosis and tight junction disruption in the intestine of human II/R patients. Meanwhile, NETs aggravated Caco-2 intestinal epithelial cell necroptosis, impairing the monolayer barrier in vitro. Moreover, Pad4-deficient mice were used further to validate the role of NETs in II/R-induced intestinal injury. In contrast, NET inhibition via Pad4 deficiency alleviated intestinal inflammation, attenuated cellular necroptosis, improved intestinal permeability, and enhanced tight junction protein expression. Notably, NETs prevented FUN14 domain-containing 1 (FUNDC1)-required mitophagy activation in intestinal epithelial cells, and stimulating mitophagy attenuated NET-associated mitochondrial dysfunction, cellular necroptosis, and intestinal damage. Mechanistically, silencing Toll-like receptor 4 (TLR4) or receptor-interacting protein kinase 3 (RIPK3) via shRNA relieved mitophagy limitation, restored mitochondrial function and reduced NET-induced necroptosis in Caco-2 cells, whereas this protective effect was reversed by TLR4 or RIPK3 overexpression. The regulation of TLR4/RIPK3/FUNDC1-required mitophagy by NETs can potentially induce intestinal epithelium necroptosis.

Damage control surgery in emergency general surgery: What you need to know

ABSTRACT

Damage-control surgery (DCS) is a strategy adopted to limit initial operative interventions in the unstable surgical patient, delaying definitive repairs and abdominal wall closure until physiologic parameters have improved. Although this concept of "physiology over anatomy" was initially described in the management of severely injured trauma patients, the approaches of DCS have become common in the management of nontraumatic intra-abdominal emergencies.While the utilization of damage-control methods in emergency general surgery (EGS) is controversial, numerous studies have demonstrated improved outcomes, making DCS an essential technique for all acute care surgeons. Following a brief history of DCS and its indications in the EGS patient, the phases of DCS will be discussed including an in-depth review of preoperative resuscitation, techniques for intra-abdominal source control, temporary abdominal closure, intensive care unit (ICU) management of the open abdomen, and strategies to improve abdominal wall closure.

Neutrophil extracellular traps drive intestinal microvascular endothelial ferroptosis by impairing Fundc1-dependent mitophagy

Microvascular endothelial damage caused by intestinal ischemia‒reperfusion (II/R) is a primary catalyst for microcirculation dysfunction and enterogenous infection. Previous studies have mainly focused on how neutrophil extracellular traps (NETs) and ferroptosis cause intestinal epithelial injury, and little attention has been given to how NETs, mainly from circulatory neutrophils, affect intestinal endothelial cells during II/R. This study aimed to unravel the mechanisms through which NETs cause intestinal microvascular dysfunction. We first detected heightened local NET infiltration around the intestinal microvasculature, accompanied by increased endothelial cell ferroptosis, resulting in microcirculation dysfunction in both human and animal II/R models. However, the administration of the ferroptosis inhibitor ferrostatin-1 or the inhibition of NETs via neutrophil-specific peptidylarginine deiminase 4 (Pad4) deficiency led to positive outcomes, with reduced intestinal endothelial ferroptosis and microvascular function recovery. Moreover, RNA-seq analysis revealed a significant enrichment of mitophagy- and ferroptosis-related signaling pathways in HUVECs incubated with NETs. Mechanistically, elevated NET formation induced Fundc1 phosphorylation at Tyr18 in intestinal endothelial cells, which led to mitophagy inhibition, mitochondrial quality control imbalance, and excessive mitochondrial ROS generation and lipid peroxidation, resulting in endothelial ferroptosis and microvascular dysfunction. Nevertheless, using the mitophagy activator urolithin A or AAV-Fundc1 transfection could reverse this process and ameliorate microvascular damage. We first demonstrate that increased NETosis could result in intestinal microcirculatory dysfunction and conclude that suppressed NET formation can mitigate intestinal endothelial ferroptosis by improving Fundc1-dependent mitophagy. Targeting NETs could be a promising approach for treating II/R-induced intestinal microcirculatory dysfunction.

Hypercoagulability status, operative mortality, and long-term survival in patients operated on for mesenteric venous thrombosis

OBJECTIVE

Mesenteric venous thrombosis (MVT) is a rare cause of acute surgical abdomen, with high mortality. The aim of this study was to analyze long-term outcomes and possible factors influencing its prognosis.

METHODS

All patients who underwent urgent surgery for MVT from 1990 to 2020 in our center were reviewed. Epidemiological, clinical, and surgical data; postoperative outcomes; origin of thrombosis; and long-term survival were analyzed. Patients were divided into two groups: primary MVT (hypercoagulability disorders or idiopathic MVT) and secondary MVT (underlying disease).

RESULTS

Fifty-five patients, 36 (65.5%) men and 19 (34.5%) women, mean age 66.7 years (standard deviation: ±18.0 years), underwent surgery for MVT. Arterial hypertension (63.6%) was the most prevalent comorbidity. Regarding the possible origin of MVT, 41 (74.5%) patients had primary MVT and 14 (25.5%) patients had secondary MVT. From these, 11 (20%) patients had hypercoagulable states, 7 (12.7%) had neoplasia, 4 (7.3%) had abdominal infection, 3 (5.5%) had liver cirrhosis, 1 (1.8%) patient had recurrent pulmonary thromboembolism, and 1 (1.8%) had deep venous thrombosis. Computed tomography was diagnostic of MVT in 87.9% of the cases. Intestinal resection was performed in 45 patients due to ischemia. Only 6 patients (10.9%) had no complication, 17 patients (30.9%) presented minor complications, and 32 patients (58.2%) presented severe complications according to the Clavien-Dindo classification. Operative mortality was 23.6%. In univariate analysis, comorbidity measured by the Charlson index (P = .019) and massive ischemia (P = .002) were related to operative mortality. The probability of being alive at 1, 3, and 5 years was 66.4%, 57.9%, and 51.0%, respectively. In univariate analysis of survival, age (P < .001), comorbidity (P < .001), and type of MVT (P = .003) were associated with a good prognosis. Age (P = .002; hazard ratio: 1.05, 95% confidence interval: 1.02-1.09) and comorbidity (P = .019; hazard ratio: 1.28, 95% confidence interval: 1.04-1.57) behaved as independent prognostic factors for survival.

CONCLUSIONS

Surgical MVT continues to show high lethality. Age and comorbidity according to the Charlson index correlate well with mortality risk. Primary MVT tends to have a better prognosis than secondary MVT.

Potential for intestinal transplantation after acute mesenteric ischemia in patients aged less than 70 years: A population-based study

BACKGROUND AND OBJECTIVE

Acute mesenteric ischemia (AMI) has a high mortality rate due to the development of bowel necrosis. Patients are often ruled outside active care if a large proportion of small bowel is necrotic. With the development of treatment for short bowel syndrome (SBS) and intestinal transplantation methods, long-term survival is possible even after extensive small bowel resections. This study aims to assess the incidence of SBS and potentially suitable candidates for intestinal transplantation among patients treated for AMI.

METHODS

This population-based retrospective study comprised patients aged less than 70 years and diagnosed with AMI between January 2006 and October 2020 in Helsinki and Uusimaa health care district, Finland.

RESULTS

Altogether, AMI was diagnosed in 711 patients, of whom 133 (19%) were aged below 70. An intervention was performed in 110 (83%) patients. Of these 133 patients, 16 (12%) were ruled outside active treatment due to extensive small bowel necrosis at exploratory laparotomy, of whom 6 (5%) were potentially suitable for intestinal transplantation. Two patients were considered as potential candidates for intestinal transplantation at bowel resection but died of AMI. Nine (7%) patients needed parenteral nutrition after resection, and two of them (2%) developed SBS. Only one patient needed long-term parenteral nutrition after hospital discharge. This patient remained dependent on parenteral nutrition but died before evaluation of intestinal transplantation could be carried out while the other patient was able to return to enteral nutrition.

CONCLUSIONS

A small number of patients with AMI below 70 years of age are potentially eligible for intestinal transplantation.

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

OBJECTIVE

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

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

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

ELIGIBILITY CRITERIA

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

DATA EXTRACTION AND SYNTHESIS

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

RESULTS

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

CONCLUSIONS

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

PROSPERO REGISTRATION NUMBER

CRD42021247148.

Damage-control surgery in patients with nontraumatic abdominal emergencies: A systematic review and meta-analysis

BACKGROUND

After the successful implementation in trauma, damage-control surgery (DCS) is being increasingly used in patients with nontraumatic emergencies. However, the role of DCS in the nontrauma setting is not well defined. The aim of this study was to investigate the effect of DCS on mortality in patients with nontraumatic abdominal emergencies.

METHODS

Systematic literature search was done using PubMed. Original articles addressing nontrauma DCS were included. Two meta-analyses were performed, comparing (1) mortality in patients undergoing nontrauma DCS versus conventional surgery (CS) and (2) the observed versus expected mortality rate in the DCS group. Expected mortality was derived from Acute Physiology And Chronic Health Evaluation, Simplified Acute Physiology Score, and Portsmouth Physiological and Operative Severity Score for enUmeration of Mortality and Morbidity scores.

RESULTS

A total of five nonrandomized prospective and 16 retrospective studies were included. Nontrauma DCS was performed in 1,238 and nontrauma CS in 936 patients. Frequent indications for surgery in the DCS group were (weighted proportions) hollow viscus perforation (28.5%), mesenteric ischemia (26.5%), anastomotic leak and postoperative peritonitis (19.6%), nontraumatic hemorrhage (18.4%), abdominal compartment syndrome (17.8%), bowel obstruction (15.5%), and pancreatitis (12.9%). In meta-analysis 1, including eight studies, mortality was not significantly different between the nontrauma DCS and CS group (risk difference, 0.09; 95% confidence interval, -0.06 to 0.24). Meta-analysis 2, including 14 studies, revealed a significantly lower observed than expected mortality rate in patients undergoing nontrauma DCS (risk difference, -0.18; 95% confidence interval, -0.29 to -0.06).

CONCLUSION

This meta-analysis revealed no significantly different mortality in patients undergoing nontrauma DCS versus CS. However, observed mortality was significantly lower than the expected mortality rate in the DCS group, suggesting a benefit of the DCS approach. Based on these two findings, the effect of DCS on mortality in patients with nontraumatic abdominal emergencies remains unclear. Further prospective investigation into this topic is warranted.

LEVEL OF EVIDENCE

Systematic review and meta-analysis, level III.

Usefulness of damage control approach in patients with limited acute mesenteric ischemia: a prospective study of 85 patients

To evaluate the efficacy of the damage control approach by two-step surgical procedure in not critical patients (without sepsis or septic shock) with peritonitis from limited acute mesenteric ischemia. From April 2013 to April 2020, 85 patients [49 (57.7%) women and 36 (42.3%) men, median age 69.5 (range 38-92)] were enrolled in this study and underwent emergency surgery. After resection of ischemic bowel, basing on the individual decision of the single surgeon, the patients underwent primary end-to-end anastomosis (Group 1) or damage control approach (Group 2) including primary laparotomy with resection of ischemic bowel, temporary abdominal closure and a second-look procedure at 48 h with re-evaluation of bowel vitality. Forty-seven (55.3%) patients underwent one-stage surgical treatment and 38 (44.7%) patients received a two-step procedure. In the latter group, at second exploration, 8 (21%) patients required a further intestinal resection, due to mesenteric ischemia progression. Both anastomosis dehiscence rate and need for ileostomy in Group 1 patients were significantly higher than in Group 2 (23.4% vs 5.3%: p = 0.03 and 19.1% vs 2.6%: p = 0.03; Fisher's exact test). No significative differences in mortality and morbidity rate were found between the two groups. The damage control approach by two-step surgical procedure may represent a valid innovative option in the management of not critical patients with limited acute mesenteric ischemia, achieving a better clinical outcome if compared with surgical treatment by one-step procedure.

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

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

A clinical approach to acute mesenteric ischemia

PURPOSE OF REVIEW

To summarize current evidence on acute mesenteric ischemia (AMI) in critically ill patients, addressing pathophysiology, definition, diagnosis and management.

RECENT FINDINGS

A few recent studies showed that a multidiscipliary approach in specialized centers can improve the outcome of AMI. Such approach incorporates current knowledge in pathophysiology, early diagnosis with triphasic computed tomography (CT)-angiography, immediate endovascular or surgical restoration of mesenteric perfusion, and damage control surgery if transmural bowel infarction is present. No specific biomarkers are available to detect early mucosal injury in clinical setting. Nonocclusive mesenteric ischemia presents particular challenges, as the diagnosis based on CT-findings as well as vascular management is more difficult; some recent evidence suggests a possible role of potentially treatable stenosis of superior mesenteric artery and beneficial effect of vasodilator therapy (intravenous or local intra-arterial). Medical management of AMI is supportive, including aiming of euvolemia and balanced systemic oxygen demand/delivery. Enteral nutrition should be withheld during ongoing ischemia-reperfusion injury and be started at low rate after revascularization of the (remaining) bowel is convincingly achieved.

SUMMARY

Clinical suspicion leading to tri-phasic CT-angiography is a mainstay for diagnosis. Diagnosis of nonocclusive mesenteric ischemia and early intestinal injury remains challenging. Multidisciplinary team effort may improve the outcome of AMI.

Interdisciplinary Management of Visceral Artery Aneurysms and Visceral Artery Pseudoaneurysms

The paper presents the results of treating 14 patients, namely eight patients with visceral artery aneurysms and six patients with visceral artery pseudoaneurysms. In 64.3% of the patients, the initial diagnosis was made based on the ultrasound examination. All the patients (100%) underwent CT angiography, while angiography was performed in 71.4% of the cases. Five (35.7%) patients with visceral artery pseudoaneurysms were emergently hospitalized; among them, the signs of bleeding were observed in 2 patients. In 9 patients, pathology was detected during tests for other conditions. Five (35.7%) patients underwent endovascular treatment, while 9 (64.3%) patients received surgical treatment. Endovascular interventions and open surgery demonstrated a nil mortality rate. After endovascular treatment, stent thrombosis was found in 1 patient. In the case of surgical treatment, visceral artery aneurysm was observed in 1 patient who underwent the resection of superior mesenteric artery pseudoaneurysm. Conclusions. The choice of the method of treating visceral artery aneurysms and visceral artery pseudoaneurysms depends on the location, size, anatomic features of the visceral arteries and the clinical course of the disease. Both endovascular and surgical treatment demonstrate good postoperative outcomes. Visceral ischemia is one of the most serious complications in the postoperative period, which can complicate both the diagnosis and the choice of treatment tactics.

The Association of Coloproctology of Great Britain and Ireland consensus guidelines in emergency colorectal surgery

AIM

There is a requirement for an expansive and up to date review of the management of emergency colorectal conditions seen in adults. The primary objective is to provide detailed evidence-based guidelines for the target audience of general and colorectal surgeons who are responsible for an adult population and who practise in Great Britain and Ireland.

METHODS

Surgeons who are elected members of the Association of Coloproctology of Great Britain and Ireland Emergency Surgery Subcommittee were invited to contribute various sections to the guidelines. They were directed to produce a pathology-based document using literature searches that were systematic, comprehensible, transparent and reproducible. Levels of evidence were graded. Each author was asked to provide a set of recommendations which were evidence-based and unambiguous. These recommendations were submitted to the whole guideline group and scored. They were then refined and submitted to a second vote. Only those that achieved >80% consensus at level 5 (strongly agree) or level 4 (agree) after two votes were included in the guidelines.

RESULTS

All aspects of care (excluding abdominal trauma) for emergency colorectal conditions have been included along with 122 recommendations for management.

CONCLUSION

These guidelines provide an up to date and evidence-based summary of the current surgical knowledge in the management of emergency colorectal conditions and should serve as practical text for clinicians managing colorectal conditions in the emergency setting.

Is open abdominal management useful in nontrauma emergency surgery for older adults? A single-center retrospective study

PURPOSE

Open abdominal management (OAM) is being adopted increasingly frequently in nontrauma patients. This study assessed the effectiveness of OAM in nontrauma older adults.

METHODS

We retrospectively reviewed all adults who underwent nontrauma emergency laparotomy requiring postoperative intensive care unit (ICU) management between September 2012 and August 2017 at our hospital. Patients ≥ 80 years old, who underwent OAM, were compared with those < 80 years old. The primary outcome was the 90-day mortality. Secondary outcomes were the 30-day mortality, unplanned relaparotomy, and the ICU length of stay (LOS).

RESULTS

The OAM group comprised 58 patients, including 27 who were ≥ 80 years old. The patients ≥ 80 years old in the OAM group had a significantly higher 90-day mortality rate (33% vs. 10%; p = 0.027) than those < 80 years old. There were no significant differences in the 30-day mortality rate, patients' unplanned relaparotomy rate, or ICU LOS between the patients ≥ 80 years old and those < 80 in the OAM group.

CONCLUSIONS

Older adults who underwent OAM had a significantly higher mortality rate than younger patients. However, the OAM strategy for older nontrauma patients may still be useful and reasonable considering the severe condition of these patients.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

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

Outcomes of antegrade and retrograde open mesenteric bypass for acute mesenteric ischemia

BACKGROUND

Acute mesenteric ischemia (AMI) is a challenging clinical problem associated with significant morbidity and mortality. Few contemporary reports focus specifically on patients undergoing open mesenteric bypass (OMB) or delineate outcome differences based on bypass configuration. This is notable, because there is a subset of patients who are poor candidates for endovascular intervention including those with flush mesenteric vessel occlusion, long segment occlusive disease, and a thrombosed mesenteric stent and/or bypass. This analysis reviewed our experience with OMB in the treatment of AMI and compared outcomes between patients undergoing either antegrade or retrograde bypass.

METHODS

A single-center, retrospective review was performed to identify all patients who underwent OMB for AMI from 2002 to 2016. A preoperative history of mesenteric revascularization, demographics, comorbidities, operative details, and outcomes were abstracted. The primary end point was in-hospital mortality. Secondary end points included complications, reintervention, and overall survival. Kaplan-Meier estimation and Cox proportional hazards regression were used to analyze all end points.

RESULTS

Eighty-two patients (female 54%; age 63 ± 12 years) underwent aortomesenteric bypass (aortoceliac/superior mesenteric, n = 44; aortomesenteric, n = 38) for AMI. A history of prior stent/bypass was present in 20% (n = 16). A majority (76%; n = 62) underwent antegrade bypass and the remainder received retrograde infrarenal aortoiliac inflow. Patients receiving antegrade OMB were more likely to be male (53% vs 25%; P = .02), have coronary artery disease (48% vs 25%; P = .06), chronic obstructive pulmonary disease (52% vs 25%; P = .03), and peripheral arterial disease (60% vs 35%; P = .05). Concurrent bowel resection was evenly distributed (antegrade, 45%; retrograde, 45%; P = .9) and 37% (n = 30) underwent subsequent resection during second look operations. The median duration of stay was 16 days (interquartile range, 9-35 days) and 78% (n = 64) experienced at least one major complication with no difference in rates between antegrade/retrograde configurations. In-hospital mortality was 37% (n = 30; multiple organ dysfunction, 22; bowel infarction, 4; hemorrhage/anemia, 2; arrhythmia, 1; stroke, 1; 30-day mortality, 26%). The median follow-up was 8 months (interquartile range, 1-26 months). The 1- and 3-year primary patency rates were both 82% ± 6% (95% confidence interval, 71%-95%), with 10 patients requiring reintervention. Estimated survival at 1 and 5 years was 57% ± 6% and 50% ± 6%, respectively. Bypass configuration was not associated with complication rates (P > .10), in-hospital mortality (log-rank, P = .3), or overall survival (log-rank, P = .9). However, a higher risk of reintervention was observed in patients undergoing retrograde bypass (hazard ratio, 3.0; 95% confidence interval, 0.9-11.0; P = .08).

CONCLUSIONS

OMB for AMI results in significant morbidity and mortality, irrespective of bypass configuration. Antegrade OMB is associated with comparable outcomes as retrograde OMB. The bypass configuration choice should be predicated on patient presentation, anatomy, physiology, and surgeon preference; however, an antegrade configuration may provide a lower risk of reintervention.