Non-occlusive mesenteric ischaemia: a common disorder in gastroenterology and intensive care

A case of non-occlusive mesenteric ischemia following hepatocellular carcinoma rupture

Hepatocellular carcinoma (HCC) rupture is a severe complication, yet there is limited literature on cases complicated by subsequent non-occlusive mesenteric ischemia (NOMI). A 77-year-old man presented to our hospital with abdominal pain and shock. Arterial phase computed tomography (CT) hepatic arteriography revealed a 77-mm HCC in the left lobe with active extravasation, and the feeding artery was embolized. Although the abdominal pain initially subsided after the procedure, it recurred the next day. A contrast-enhanced CT scan revealed pneumatosis intestinalis and decreased enhancement of the small intestinal wall. The patient underwent resection of the affected segment of the small intestine and was ultimately diagnosed with NOMI based on pathological findings. This is the first reported case of NOMI following HCC rupture. Given the high mortality associated with these conditions, clinicians should be aware of this rare complication and ensure comprehensive evaluation and timely intervention to improve patient outcomes.

When can we start early enteral nutrition safely in patients with shock on vasopressors?

Shock is a common critical illness characterized by microcirculatory disorders and insufficient tissue perfusion. Patients with shock and hemodynamic instability generally require vasopressors to maintain the target mean arterial pressure. Enteral nutrition (EN) is an important therapeutic intervention in critically ill patients and has unique benefits for intestinal recovery. However, the initiation of early EN in patients with shock receiving vasopressors remains controversial. Current guidelines make conservative and vague recommendations regarding early EN support in patients with shock. Increasing studies demonstrates that early EN delivery is safe and feasible in patients with shock receiving vasopressors; however, this evidence is based on observational studies. Changes in gastrointestinal blood flow vary by vasopressor and inotrope and are complex. The risk of gastrointestinal complications, especially the life-threatening complications of non-occlusive mesenteric ischemia and non-occlusive bowel necrosis, cannot be ignored in patients with shock during early EN support. It remains a therapeutic challenge in critical care nutrition therapy to determine the initiation time of EN in patients with shock receiving vasopressors and the safe threshold region for initiating EN with vasopressors. Therefore, the current review aimed to summarize the evidence on the optimal and safe timing of early EN initiation in patients with shock receiving vasopressors to improve clinical practice.

Association between Postoperative Adjuvant Vasodilator Therapy and In-Hospital Mortality for Non-Occlusive Mesenteric Ischemia: A Nationwide Observational Study

BACKGROUND

Although several clinical guidelines recommend vasodilator therapy for non-occlusive mesenteric ischemia (NOMI) and immediate surgery when bowel necrosis is suspected, these recommendations are based on limited evidence.

METHODS

In this retrospective nationwide observational study, we used information from the Japanese Diagnosis Procedure Combination inpatient database from July 2010 to March 2018 to identify patients with NOMI who underwent abdominal surgeries on the day of admission. We compared patients who received postoperative vasodilator therapy (vasodilator group) with those who did not (control group). Vasodilator therapy was defined as venous and/or arterial administration of papaverine and/or prostaglandin E1 within 2 days of admission. The primary outcome was in-hospital mortality. Secondary outcomes included the prevalence of additional abdominal surgery performed ≥3 days after admission and short bowel syndrome.

RESULTS

We identified 928 eligible patients (149 in the vasodilator group and 779 in the control group). One-to-four propensity score matching yielded 149 and 596 patients for the vasodilator and control groups, respectively. There was no significant difference in in-hospital mortality between the groups (control vs. vasodilator, 27.5% vs. 30.9%; risk difference, 3.4%; 95% confidence interval, -4.9 to 11.6; p=0.42) and no significant difference in the prevalences of abdominal surgery, bowel resection ≥3 days after admission, and short bowel syndrome.

CONCLUSIONS

Postoperative vasodilator use was not significantly associated with a reduction in in-hospital mortality or additional abdominal surgery performed ≥3 days after admission in surgically treated NOMI patients.

Advances in the diagnosis of non-occlusive mesenteric ischemia and challenges in intra-abdominal sepsis patients: a narrative review

Non-occlusive mesenteric ischemia (NOMI) is a type of acute mesenteric ischemia (AMI) with a high mortality rate mainly because of a delayed or misdiagnosis. Intra-abdominal sepsis is one of the risk factors for developing NOMI, and its presence makes early diagnosis much more difficult. An increase in routine abdominal surgeries carries a corresponding risk of abdominal infection, which is a complication that should not be overlooked. It is critical that physicians are aware of the possibility for intestinal necrosis in abdominal sepsis patients due to the poor survival rate of NOMI. This review aims to summarize advances in the diagnosis of NOMI, and focuses on the diagnostic challenges of mesenteric ischemia in patients with intra-abdominal sepsis.

Nonocclusive mesenteric ischemia caused by type B aortic dissection: a case report

Background

Nonocclusive mesenteric ischemia (NOMI) is defined as acute intestinal ischemia because of decreased blood flow in mesenteric vessels. Only a few cases of NOMI that occur secondary to aortic dissection (AD) have been reported, resulting in the lack of sufficient knowledge of diagnosis and treatment.

Case presentation

We aimed to report a case of NOMI caused by type B Aortic Dissection. A 26-year-old male patient was transferred to our hospital with the diagnose of NOMI and aortic dissection in April 2018. The abdominal computed tomography (CT) assists the diagnosis of paralytic intestinal obstruction, intestinal wall pneumatosis, and perforation. Emergency laparotomy revealed that the bowel wall supplied by the superior mesenteric artery (SMA) was pale with the palpable but weak pulsation of the parietal artery. The small intestine was extremely dilated with a paper-thin, fragile wall that was ruptured easily and could not be sutured. In this case, extensive resection and segmental drainage were done. Postoperatively, the digestive tract was reconstructed. However, the patient suffered from iron deficiency anemia and short bowel syndrome eight months later, and unfortunately died from long-term complications.

Conclusion

Aortic dissection leads to continuous decrease in blood pressure and blood flow to the SMA, considering as a predisposing factor for NOMI. During the treatment, extensive resection and segmental drainage are the optimal surgical strategy, which can make benefit in emergencies especially.

Acute Mesenteric Ischemia

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

Post-Cardiac Arrest Syndrome Is Not Associated With an Early Bacterial Translocation

BACKGROUND

The aim of this study was to investigate bacterial translocation and its possible role in the development of post-resuscitation inflammatory response following Cardio-Pulmonary Resuscitation (CPR) after cardiac arrest.

METHODS

Munich female swine were employed for a model of cardiac arrest via application of electrical current. After 7 min, CPR was initiated, and animals were either successfully return to spontaneous circulation (ROSC) within 40 min or not (no-ROSC). At the end of experimental period and prior to sacrifice, samples from the intestine, mesenteric lymph nodes (MLN), liver and portal vein blood were obtained. Evaluation of inflammation and gut permeability was performed; MLN, liver and portal vein samples were analyzed for 16 s rRNA detection and cytokine mRNA expression.

RESULTS

A decreased expression of the tight junction protein Occludin, with higher levels of inflammation, greater epithelial disintegration, ulceration, loss of crypts and villi height were found in the intestines of the ROSC swine in comparison to no-ROSC. The macrophage surface antigen CD-14 staining was relatively more intense in the ROSC than in no-ROSC. Higher levels of TNF-α mRNA expression were present in the liver of the ROSC group. Finally, despite the inflammatory response and the gut mucosal alterations in ROSC group, no bacterial translocation was detected in liver, MLN and portal vein.

CONCLUSIONS

We show that resuscitation from cardiac arrest induces inflammatory response and intestinal permeability in swine 4h after resuscitation, but not a bacterial translocation. Bacterial translocation is not an early phase phenomenon but probably part of the pathophysiologic sequelae.

Abdominal imaging in ICU patients with viral pneumonia: Are findings in COVID-19 patients really different from those observed with non-SARS-CoV-2 viral pneumonia?

Purpose

To evaluate and compare the prevalence and type of abdominal involvements identified on CT scans in COVID-19 critically ill patients to those observed in critically ill patients with non-SARS-CoV-2 viral pneumonia.

Methods

Monocentric IRB approved retrospective study comparing all abdominal CT scans performed for patients admitted in the ICU with COVID-19 and those performed in a historical cohort of ICU patients with non-SARS-CoV-2 viral pneumonia. For each patient, gallbladder abnormality, acute pancreatitis signs, acute adrenal infarction, renal infarcts, bowel wall thickening and CT scan signs of bowel ischemia were assessed. Results were then compared between critically ill COVID-19 and non-COVID-19 patients (Chi-2 or Fisher exact tests for categorical data and Student t-test or Mann-Whitney U test for continuous data as appropriate).

Results

Ninety-nine COVID-19 patients and 45 non-COVID-19 patients were included.

No difference was found between the rate of abnormal findings comparing COVID-19 patients and patients with other viral pneumonia (63/99 [64%] vs 27/45 [61%], p=0.94). Acute pancreatitis signs were more commonly seen in COVID-19 patients but without statistically difference between groups (14/99 [14%] vs 3/45 [6.7%], p=0.31). Bowel wall thickening was slightly more commonly seen in patients with other viral pneumonia (18/99 [18%] vs 11/45 [24%], p=0.52), however ischemic features were observed in higher rate in the COVID-19 group, although without reaching statistically significant differences (7/99 [7.1%] vs 2/45 [4.4%], p=0.75).

Conclusion

The rate and severity of abdominal involvement demonstrated by CT in ICU patients hospitalized for COVID-19 although high were not different to that observed in patients with other severe viral pneumoniae

Non-Occlusive Mesenteric Ischemia in Children With Diabetic Ketoacidosis: Case Report and Review of Literature

INTRODUCTION

Despite the use of technology, recurrent diabetic ketoacidosis (DKA) prevention remains an unmet need in children and adolescents with T1D and may be accompanied by life-threatening acute complications. We present a rare case of non-occlusive mesenteric ischemia (NOMI) with overt manifestation after DKA resolution and a discussion of recent literature addressing DKA-associated NOMI epidemiology and pathogenesis in children and adolescents.

CASE PRESENTATION

A 13-year-old female with previously diagnosed T1D, was admitted at our emergency department with hypovolemic shock, DKA, hyperosmolar state and acute kidney injury (AKI). Mildly progressive abdominal pain persisted after DKA correction and after repeated ultrasound evaluations ultimately suspect for intestinal perforation, an intraoperative diagnosis of NOMI was made.

CONCLUSION

The diagnosis of DKA-associated NOMI must be suspected in pediatric patients with DKA, persistent abdominal pain, and severe dehydration even after DKA resolution.

Acute Mesenteric Ischemia: A Challenge for the Acute Care Surgeon

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

Vasodilator Therapy and Mortality in Nonocclusive Mesenteric Ischemia: A Nationwide Observational Study

OBJECTIVES

Previous studies have suggested that vasodilator therapy may be beneficial for patients with nonocclusive mesenteric ischemia. However, robust evidence supporting this contention is lacking. We examined the hypothesis that vasodilator therapy may be effective in patients diagnosed with nonocclusive mesenteric ischemia.

DESIGN

Retrospective cohort study.

SETTING

The Japanese Diagnosis Procedure Combination inpatient database.

PATIENTS

A total of 1,837 patients with nonocclusive mesenteric ischemia from July 2010 to March 2018.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We compared patients who received vasodilator therapy (vasodilator group; n = 161) and those who did not (control group; n = 1,676) using one-to-four propensity score matching. Vasodilator therapy was defined as papaverine and/or prostaglandin E1 administered via venous and/or arterial routes within 2 days of admission. Only patients who did not receive abdominal surgery within 2 days of admission were analyzed. The main outcomes were in-hospital mortality and abdominal surgery performed greater than or equal to 3 days after admission. After propensity score matching, in-hospital mortality was significantly lower in the vasodilator group (risk difference, -11.6%; p = 0.005). The proportion of patients who received abdominal surgery at greater than or equal to 3 days after admission was also significantly lower in the vasodilator group (risk difference, -10.2%; p = 0.002).

CONCLUSIONS

Vasodilator therapy with papaverine and/or prostaglandin E1 is associated with lower in-hospital mortality and prevalence of abdominal surgery in patients with nonocclusive mesenteric ischemia.

Pearls, Pitfalls, and Conditions that Mimic Mesenteric Ischemia at CT

Acute mesenteric ischemia (AMI) is a life-threatening condition with a high mortality rate. The diagnosis of AMI is challenging because patient symptoms and laboratory test results are often nonspecific. A high degree of clinical and radiologic suspicion is required for accurate and timely diagnosis. CT angiography of the abdomen and pelvis is the first-line imaging test for suspected AMI and should be expedited. A systematic "inside-out" approach to interpreting CT angiographic images, beginning with the bowel lumen and proceeding outward to the bowel wall, mesentery, vasculature, and extraintestinal viscera, provides radiologists with a practical framework to improve detection and synthesis of imaging findings. The subtypes of AMI are arterial and venoocclusive disease, nonocclusive ischemia, and strangulating bowel obstruction; each may demonstrate specific imaging findings. Chronic mesenteric ischemia is more insidious at onset and almost always secondary to atherosclerosis. Potential pitfalls in the diagnosis of AMI include mistaking pneumatosis as a sign that is specific for AMI and not an imaging finding, misinterpretation of adynamic ileus as a benign finding, and pseudopneumatosis. Several enterocolitides can mimic AMI at CT angiography, such as inflammatory bowel disease, infections, angioedema, and radiation-induced enterocolitis. Awareness of pitfalls, conditions that mimic AMI, and potential distinguishing clinical and imaging features can assist radiologists in making an early and accurate diagnosis of AMI. ^©RSNA, 2020.

Non-oclusive mesenteric ischemia as a complication of dialysis

We present the case of a 69-year-old male ex-smoker, whose medical background included hypertension, chronic renal failure, atrial fibrillation anticoagulation, and chronic lower limb arterial ischemia. He suffered from abdominal pain associated with nausea and vomiting after a hemodialysis session. The analysis showed C-reactive protein at 7 mg/L, 14,500 leukocytes with neutrophilia, and lactate at 2.8. A computerized axial tomography (CAT) scan was performed and portal pneumatosis as well as a distal ileum segment with intestinal pneumatosis were observed, which was compatible with non-occlusive mesenteric ischemia.

Non-occlusive mesenteric ischemia (NOMI): evaluation of 2D-perfusion angiography (2D-PA) for early treatment response assessment

Purpose

To evaluate the feasibility of 2D-perfusion angiography (2D-PA) for the analysis of intra-procedural treatment response after intra-arterial prostaglandin E1 therapy in patients with non-occlusive mesenteric ischemia (NOMI).

Methods

Overall, 20 procedures in 18 NOMI patients were included in this retrospective case–control study. To evaluate intra-procedural splanchnic circulation changes, post-processing of digital subtraction angiography (DSA) series was performed. Regions of interest (ROIs) were placed in the superior mesenteric artery (SMA; reference), the portal vein (PV; ROI_PV), as well as the aorta next to the origin of the SMA (ROI_Aorta). Peak density (PD), time to peak (TTP), and area under the curve (AUC) were assessed, and parametric ratios ‘target ROI_{PD, TTP, AUC}/reference ROI’ were computed and compared within treatment and control group. Additionally, a NOMI score was assessed pre- and post-treatment compared to 2D-PA.

Results

Vasodilator therapy leads to a significant decrease of the 2D-PA-derived values PD_Aorta (p = 0.04) and AUC_Aorta (p = 0.03). These findings correlated with changes of the simplified NOMI score, both for overall (4 to 1, p < 0.0001) and for each category. Prostaglandin application caused a significant increase of the AUC_PV (p = 0.04) and TTP_PV was accelerated without reaching statistical significance (p = 0.13). When compared to a control group, all 2D-PA values in the NOMI group (pre- and post-intervention) differed significantly (p < 0.05) with longer TTP_Aorta/PV and lower AUC_Aorta/PV and PD _Aorta/PV.

Conclusion

2D-PA offers an objective approach to analyze immediate flow and perfusion changes following vasodilatory therapies of NOMI patients and may be a valuable tool for assessing treatment response.

The Incidence of Chronic Mesenteric Ischemia in the Well-Defined Region of a Dutch Mesenteric Ischemia Expert Center

INTRODUCTION

This study aimed to determine the incidence of chronic mesenteric ischemia (CMI) and to examine the influence of the etiological cause, location, and severity of a mesenteric artery stenosis on the probability of having CMI.

METHODS

A prospective database, containing the details of all patients with suspected CMI referred to a renowned CMI expert center, was used. Patients residing within the expert centers' well-defined region, between January 2014 and October 2019, were included. CMI was diagnosed when patients experienced sustained symptom improvement after treatment.

RESULTS

This study included 358 patients, 75 had a ≥50% atherosclerotic stenosis of 1 vessel (CMI 16%), 96 of 2 or 3 vessels (CMI 81%), 81 celiac artery compression (CMI 25%), and 84 no stenosis (CMI 12%). In total, 138 patients were diagnosed with CMI, rendering a mean incidence of 9.2 (95% confidence interval [CI] 6.2-13.7) per 100,000 inhabitants. Atherosclerotic CMI was most common, with a mean incidence of 7.2 (95% CI 4.6-11.3), followed by median arcuate ligament syndrome 1.3 (95% CI 0.5-3.6) and chronic nonocclusive mesenteric ischemia 0.6 (95% CI 0.2-2.6). The incidence of CMI was highest in female patients (female patients 12.0 [95% CI 7.3-19.6] vs male patients 6.5 [95% CI 3.4-12.5]) and increased with age. CMI was more prevalent in the presence of a ≥70% atherosclerotic single-vessel stenosis of the superior mesenteric artery (40.6%) than the celiac artery (5.6%).

DISCUSSION

The incidence of CMI is higher than previously believed and increases with age. Probability of CMI seems highest in suspected CMI patients with multivessel disease or a ≥70% atherosclerotic single-vessel superior mesenteric artery stenosis.

An unusual cause of bowel ischemia in an intensive care unit patient with herpes simplex virus encephalitis

We present a case of an unexpected cause of bowel ischemia in an intensive care unit patient with herpes simplex virus encephalitis who required an operation. A 79-year-old lady was being worked up and treated for encephalitis with antibiotics and an antiviral. On Day 13, she developed abdominal pain, and an ultrasound showed cholelithiasis but no cholecystitis; thus conservative treatment was advocated. By Day 18, pain localized to the right iliac fossa, and she had an emergency laparotomy that showed bowel ischemia and perforation of the caecum with the cause being a terminal ileal adhesional band. An extended right hemicolectomy and ileostomy was performed. Patients with significant comorbidities who are intensive care unit-dependent may still have unexpected clinical challenges. We advocate an increased clinical vigilance in this cohort for unexpected life-threatening presentations such as bowel ischemia and more specifically the cause of the bowel ischemia.

Management of infected pancreatic necrosis in the intensive care unit: a narrative review

BACKGROUND

Severe acute pancreatitis is marked by organ failure and (peri)pancreatic necrosis with local complications such as infected necrosis. Infection of these necrotic collections together with organ failure remain the major causes of admission to an intensive care unit (ICU) in acute pancreatitis. Appropriate treatment of infected necrosis is essential to reduce morbidity and mortality. Overall knowledge of the treatment options within a multidisciplinary team-with special attention to the appropriate use of antimicrobial therapy and invasive treatment techniques for source control-is essential in the treatment of this complex disease.

OBJECTIVES

To address the current state of microbiological diagnosis, antimicrobial treatment, and source control for infected pancreatic necrosis in the ICU.

SOURCES

A literature search was performed using the Medline and Cochrane libraries for articles subsequent to 2003 using the keywords: infected necrosis, pancreatitis, intensive care medicine, treatment, diagnosis and antibiotic(s).

CONTENT

This narrative review provides an overview of key elements of diagnosis and treatment of infected pancreatic necrosis in the ICU.

IMPLICATIONS

In pancreatic necrosis it is essential to continuously (re)evaluate the indication for antimicrobial treatment and invasive source control. Invasive diagnostics (e.g. through fine-needle aspiration, FNA), preferably prior to the start of broad-spectrum antimicrobial therapy, is advocated. Antimicrobial stewardship principles apply: paying attention to altered pharmacokinetics in the critically ill, de-escalation of broad-spectrum therapy once cultures become available, and early withdrawal of antibiotics once source control has been established. This is important to prevent the development of antimicrobial resistance, especially in a group of patients who may require repeated courses of antibiotics during the prolonged course of their illness.

A Retrospective Analysis of Nonocclusive Mesenteric Ischemia in Medical and Surgical ICU Patients: Clinical Data on Demography, Clinical Signs, and Survival

Background:

To analyze demography, clinical signs, and survival of intensive care patients diagnosed with nonocclusive mesenteric ischemia (NOMI) and to evaluate the effect of a local intra-arterial prostaglandin therapy.

Methods:

Retrospective observational study screening 455 intensive care patients with acute arterial mesenteric perfusion disorder in a tertiary care hospital within the past 8 years. Lastly, 32 patients with NOMI were enrolled, of which 11 received local intra-arterial prostaglandin therapy. The diagnosis of NOMI was based on the clinical presentation and established biphasic computed tomography criteria. Clinical and biochemical data were obtained 24 hours before, at the time, and 24 hours after diagnosis.

Results:

Patients were 60.5 (49.3-73) years old and had multiple comorbidities. Most of them were diagnosed with septic shock requiring high doses of norepinephrine (NE: 0.382 [0.249-0.627] μg/kg/min). The Sequential Organ Failure Assessment (SOFA) score was 18 (16-20). A decrease in oxygenation (Pao₂/Fio₂), pH, and bicarbonate and an increase in international normalized ratio, lactate, bilirubin, leucocyte count, and NE dose were early indicators of NOMI. Median SOFA score significantly increased in the last 24 hours before diagnosis of NOMI (16 vs 18, P < .0001). Overall, 28-day mortality was 75% (81% nonintervention vs 64% intervention cohort; P = .579). Median SOFA scores 24 hours after intervention increased by +5% in the nonintervention group and decreased by 5.5% in the intervention group (P = .0059).

Conclusions:

Our data suggest that NOMI is a detrimental disease associated with progressive organ failure and a high mortality. Local intra-arterial prostaglandin application might hold promise as a rescue treatment strategy. These data encourage future randomized controlled trials are desirable.

Non-occlusive mesenteric ischemia: two case reports and a short review of the literature

INTRODUCTION

Non-occlusive mesenteric ischemia (NOMI) is an infrequent cause of acute mesenteric ischemia with atypical symptoms and a high mortality.

PATIENTS AND METHODS

We report two cases of NOMI characterized by their difference in etiology, treatment and outcome.

RESULTS

In the first case, the patient developed NOMI after septic shock, she was successfully treated with surgery. The second patient experienced two episodes of cardiac arrest followed by NOMI. He received only supportive care and died shortly after. We present a short review of the literature, discussing epidemiology, pathophysiology, clinical presentations, diagnosis and management of NOMI.

CONCLUSION

NOMI is a rare disease with a difficult diagnosis. Early recognition and treatment with supportive therapy, vasodilator drugs and possibly surgery can significantly lower mortality.

The Pathogenesis of Nonocclusive Mesenteric Ischemia: Implications for Research and Clinical Practice

Nonocclusive mesenteric ischemia (NOMI) is a condition that can encompass ischemia, inflammation, and infarction of the intestinal wall. In contrast to most patients with acute mesenteric ischemia, NOMI is distinguished by patent arteries and veins. The clinical presentation of NOMI is often insidious and nonspecific, resulting in a delayed diagnosis. Patients most at risk are those with severe acute and critical disease, including major surgery and trauma. Nonocclusive mesenteric ischemia is part of a spectrum, from mild, asymptomatic, and an unexpected finding on CT scanning, through to those exhibiting abdominal distension and peritonitis. Severe NOMI is associated with a significant mortality rate. This review of NOMI pathophysiology was conducted to document current concepts and evidence, to examine the implications for diagnosis and treatment, and to identify gaps in knowledge that might direct future research. The key pathologic mechanisms involved in the genesis of NOMI represent an exaggerated normal physiological response to maintain perfusion of vital organs at the expense of mesenteric perfusion. A supply-demand mismatch develops in the intestine due to the development of persistent mesenteric vasoconstriction resulting in reduced blood flow and oxygen delivery to the intestine, particularly to the vulnerable superficial mucosa. This mismatch can be exacerbated by raised intra-abdominal pressure, enteral nutrition, and the use of certain vasoactive drugs, ultimately resulting in the development of intestinal ischemia. Strategies for prevention, early detection, and treatment are urgently needed.

Nrf2 protects against acute lung injury and inflammation by modulating TLR4 and Akt signaling

Lung injury, which is associated with systemic inflammatory responses, is a common problem with significant morbidity and mortality. Here, we examined the involvement of toll-like receptor 4 (TLR4) and nuclear factor erythroid 2-related factor 2 (Nrf2) on intestinal ischemia-reperfusion (I/R)-induced lung injury in vivo and in vitro. Analysis of lung tissues in Nrf2-knockout mice by western blotting, immunohistochemistry, and TUNEL assay, and analysis of bronchoalveolar lavage fluid showed that Nrf2 deficiency upregulated TLR4, enhanced I/R-induced lung injury, apoptosis, inflammation, and autophagy, and increased the I/R-induced inactivation of Akt. In mouse lung epithelial cells subjected to oxygen and glucose deprivation/reperfusion (OGD/Rep), Nrf2 silencing increased the OGD/Rep-induced upregulation of TLR4 and MyD88 and downregulation of HO-1, and exacerbated OGD/Rep-induced apoptosis, autophagy, and the downregulation of phospho-Akt. TLR4 silencing and Akt inhibition experiments indicated that OGD/Rep-induced cell death by suppressing Akt signaling, and Nrf2 protected lung cells by modulating TLR4 and Akt signaling. These results indicated that the Nrf2/TLR4/Akt axis plays a role in inflammation-associated lung damage, suggesting potential therapeutic targets for the treatment of lung injury.

Diagnostic Accuracy of the Combination of Clinical Symptoms and CT or MR Angiography in Patients With Chronic Gastrointestinal Ischemia

BACKGROUND

No golden diagnostic standard is available to diagnose chronic gastrointestinal ischemia (CGI).

GOALS

We aimed to establish an accurate prediction model for CGI, based on clinical symptoms and radiologic evaluation of the amount of stenosis in the celiac artery (CA) and superior mesenteric artery (SMA) by means of computed tomography-angiography or magnetic resonance (MR)-angiography.

STUDY

We prospectively included 436 consecutive patients with clinical suspicion of CGI in a tertiary referral center. Predictors for CGI were obtained by comparing clinical parameters to the diagnosis of CGI. Multivariable logistic regression was used to combine the strongest predictors in a model. A score chart based on the prediction model was provided to calculate the risk of CGI.

RESULTS

CGI was present in 171/436 (39%) patients (67 y; range, 54 to 74 y; 27% male). Strongest predictors for CGI were female gender [odds ratio (OR)=1.44; 95% confidence interval (CI), 0.85-2.43], weight loss (OR=1.63, 95% CI, 0.98-2.72), concomitant cardiovascular disease (OR=1.70, 95% CI, 1.04-2.78), duration of symptoms (OR=0.88, 95% CI, 0.79-0.99), and stenosis of CA and SMA (50% to 70% stenosis CA: OR=1.33, 95% CI, 0.56-3.19; >70% stenosis CA: OR=5.79, 95% CI, 3.42-9.81; 50% to 70% stenosis SMA: OR=3.21, 95% CI, 0.81-12.74; >70% stenosis SMA: OR=4.39, 95% CI, 2.30-8.41). A model based on clinical symptoms alone showed limited discriminative ability for diagnosing CGI (c-statistic 0.62). Adding radiologic imaging of the mesenteric arteries improved the discriminative ability (c-statistic 0.79).

CONCLUSIONS

Clinical symptoms alone are insufficient to predict the risk of CGI. Radiologic evaluation of the mesenteric arteries is essential. This tool may be useful for clinicians to assess the risk of CGI and to decide whether further diagnostic work-up for CGI is needed.

Diagnosis and treatment of chronic mesenteric ischemia: An update

Although the prevalence of mesenteric artery stenoses (MAS) is high, symptomatic chronic mesenteric ischemia (CMI) is rare. The collateral network in the mesenteric circulation, a remnant of the extensive embryonal vascular network, serves to prevent most cases of ischemia. This explains the high incidence of MAS and relative rarity of cases of CMI. The number of affected vessels is the major determinant in CMI development. Most subjects with single vessel mesenteric stenosis do not develop ischemic complaints. Our experience is that most subjects with CA and SMA stenoses with abdominal complaints have CMI. A special mention should be made on patients with median arcuate ligament compression (MALS). There is ongoing debate whether the intermittent compression, caused by respiration movement, can cause ischemic complaints. The arguments pro and con treatment of MALS will be discussed. The clinical presentation of CMI consists of postprandial pain, weight loss, and an adapted eating pattern caused by fear of eating. In end-stage disease more continuous pain, diarrhea or a dyspepsia-like presentation can be observed. Workup of patients suspected for CMI consists of three elements: the anamnesis, the vascular anatomy and proof of ischemia. The main modalities to establish mesenteric vessel patency are duplex ultrasound, CT angiography or MR angiography. Assessing actual ischemia is still challenging, with only tonometry and visual light spectroscopy as tested candidates. Treatment consists of limiting metabolic demand, treatment of the atherosclerotic process and endovascular or operative revascularisation. Metabolic demand can be reduced by using smaller and more frequent meals, proton pump inhibition. Treatment of the atherosclerotic process consists of cessation of smoking, treatment of dyslipidemia, hypertension, hyperglycaemia, and medication with trombocyte aggregation inhibitors.

Acute mesenteric ischemia (part I) - Incidence, etiologies, and how to improve early diagnosis

Acute mesenteric ischemia (AMI) is generally thought to be a rare disease, but in fact, it is more common cause of acute abdomen than appendicitis or ruptured abdominal aortic aneurysm in patients over 75 years of age. In occlusive AMI, surgical treatment without revascularization is associated with as high as 80% overall mortality. It has been shown that early diagnosis with contrast-enhanced computed tomography and revascularization can reduce the overall mortality in AMI by up to 50%. However, only a minority of patients with AMI are being treated actively with revascularization in the United States, and the situation is very likely similar in Europe as well. What can we do to improve diagnostic performance, so that more patients get proper treatment? The diagnosis is a collaborative effort of emergency department surgeons, gastrointestinal and vascular surgeons, and radiologists. The etiological categorization of AMI should be practical and guide the therapy. Furthermore, the limitations of the diagnostic examinations need to be understood with special emphasis on computed tomography findings on patients with slowly progressing "acute-on-chronic" mesenteric ischemia.

Acute mesenteric ischemia (Part II) - Vascular and endovascular surgical approaches

The modern treatment of acute mesenteric ischemia (AMI) requires seamless collaboration of gastrointestinal surgeons, vascular surgeons, and interventional radiologists. The treatment strategy is straightforward aiming at rapid restoration of blood flow to the intestine. Bowel resection is performed on demand. The first thing to consider is the patient's clinical condition at presentation, whether there are signs of peritonitis or not, and whether the patient is hemodynamically stable or not. Second, there are four etiologies of AMI that need to be distinguished as they differ in treatment: superior mesenteric artery embolism, mesenteric arterial occlusive disease, mesenteric venous thrombosis, and non-occlusive mesenteric ischemia. In this review, we describe the basic vascular and endovascular treatment modalities accompanied by a simple algorithm for the various situations in AMI. Furthermore, the indications for damage control and primary definitive surgery are discussed.

Bowel Ischemia in Refractory Status Epilepticus: Report of Two Cases and Review of the Literature

BACKGROUND

Bowel ischemia is a rare life threatening complication seen in patients with refractory status epilepticus (RSE). The few reported cases of bowel ischemia in this setting have been associated with the use continuous barbiturate infusions. We report two patients with RSE in the absence of barbiturate infusion and without clear structural, infectious, anatomic, vascular, or autoimmune etiology. We review the clinical details of the cases and potential factors involved in the development of non-occlusive bowel ischemia in patients with RSE.

METHODS

The following is a retrospective review of two cases of non-occlusive mesenteric ischemia that occurred during the management of RSE. The clinical data and the details of pathological examination of the infarcted segments of bowel are presented in both cases.

RESULTS

In both cases, the bowel ischemia occurred in the absence of barbiturate infusion or evidence of clear thrombosis, infection, or autoimmune etiology. Case 1 had extensive ischemic necrosis of the small bowel with secondary pseudomembrane formation, and case 2 had full thickness infarction of both the large and small bowel.

CONCLUSIONS

The mechanism of bowel infarction in these cases is likely multifactorial and was not associated with barbiturate use. Likely contributors to ischemia include RSE itself, systemic hypotension, vasopressor use, general anesthesia, and abnormal cardiac function. During the management of RSE, every effort must be made to avoid the secondary complications such as bowel ischemia.

Delayed intestinal stenosis of nonocclusive mesenteric ischemia after autologous blood collection: A case report

INTRODUCTION

Nonocclusive mesenteric ischemia (NOMI) has been reported to be associated with high mortality. Early diagnosis of NOMI and prompt restoration of the intestinal blood flow is necessary in order to achieve a favorable outcome.

PRESENTATION OF CASE

We present the case of a patient who developed NOMI after autologous blood collection and was treated by selective infusion of the superior mesenteric artery with papaverine, intestinal decompression using a long intestinal tube, the administration of antibiotics, and fluid replacement. Although this non-surgical management was successful, 8 weeks after the ischemic event, segmental bowel resection was necessary because of repeated intestinal obstruction caused by bowel stricture.

DISCUSSION

Autologous blood collection might be a risk factor of NOMI. In addition, the possibility of delayed intestinal stenosis remains, even if bowel necrosis and surgical resection were avoided with non-surgical management including vasodilator therapy.

CONCLUSION

Rapid diagnosis and intervention are essential to minimize intestinal ischemia.

Update on ischemic colitis: from etiopathology to treatment including patients of intensive care unit

Ischemic colitis is the result of colonic hypoperfusion and is regarded as a relatively rare condition. It can be roughly classified as occlusive and non-occlusive. Pathogenesis includes a usually transient compromise in the colonic vasculature, with a parallel activation of an inflammatory cascade caused primarily by reperfusion. Diagnosis of ischemic colitis remains often difficult and requires a combination of diagnostic techniques, whereas clinical signs are occasionally only seen late as complications. Gold standard is considered to be colonoscopy. Clinical presentation and treatment of ischemic colitis vary widely depending on the degree of ischemia. Patients of intensive care unit (ICU) with ischemic colitis are often under-diagnosed, since the parallel co-morbidities and the nonspecific nature of symptoms that mimic almost any abdominal pathology, can mislead the doctor. Moreover, sedated or ventilated patients can mask many of the characteristic features of ischemic colitis and make the diagnosis challenging. Bedside colonoscopy and diagnostic laparoscopy in ICUs are two options, which seem lately to be reliable and promising in diagnosing ischemic colitis in critically ill patients.

Mesenteric Ischemia

Acute mesenteric ischemia (AMI) is a rare disease that most commonly affects the elderly. The vague symptoms often lead to delayed diagnosis and consequent high mortality. Physical exam and laboratory findings lack the sensitivity and specificity to exclude AMI, but computed tomography angiography can rapidly and accurately confirm the diagnosis. Survival improves with prompt restoration of perfusion and resection of nonviable bowel. Advances in imaging, operative techniques, and critical care have led to a steady decline in overall mortality; however, long-term survival is limited because of the comorbidities in this patient group.

Recent Advances of Mucosal Capnometry and the Perspectives of Gastrointestinal Monitoring in the Critically Ill. A Pilot Study

Mucosal capnometry involves the monitoring of partial pressure of carbon dioxide (PCO2) in mucous membranes. Different techniques have been developed and applied for this purpose, including sublingual or buccal sensors, or special gastrointestinal tonometric devices. The primary use of these procedures is to detect compensated shock in critically ill patients or patients undergoing major surgery. Compensatory mechanisms, in the early phases of shock, lead to the redistribution of blood flow towards the vital organs, within ostensibly typical macro-haemodynamic parameters. Unfortunately, this may result in microcirculatory disturbances, which can play a pivotal role in the development of organ failure. In such circumstances mucosal capnometry monitoring, at different gastrointestinal sites, can provide a sensitive method for the early diagnosis of shock. The special PCO2 monitoring methods assess the severity of ischaemia and help to define the necessary therapeutic interventions and testing of these monitors have justified their prognostic value. Gastrointestinal mucosal capnometry monitoring also helps in determining the severity of ischaemia and is a useful adjunctive in the diagnosis of occlusive splanchnic arterial diseases. The supplementary functional information increases the diagnostic accuracy of radiological techniques, assists in creating individualized treatment plans, and helps in follow-up the results of interventions. The results of a pilot study focusing on the interrelation of splanchnic perfusion and gastrointestinal function are given and discussed concerning recent advances in mucosal capnometry.

Necrotizing enterocolitis and the use of loop diuretics in very low birth weight neonates

BACKGROUND

Necrotizing enterocolitis (NEC) is a gastrointestinal disease of premature, very low birth weight neonates resulting in sepsis and death. Loop diuretics are widely used in neonates as a treatment for pulmonary fluid retention. An association between diuretic use and NEC has not been explored.

METHODS

The medical records of all neonates admitted to Duke Children's Hospital between 2007 and 2012 with a birth weight ≤1,500 grams were reviewed.

RESULTS

Using multivariable logistic regression analysis, we found that loop diuretic administration was not a risk factor for the development of NEC. On subanalysis, 75% of medical NEC infants had prior exposure to loop diuretics, compared with 100% of surgical NEC infants (P = .004).

CONCLUSIONS

Loop diuretics do not increase the risk of development of NEC in very low birth weight neonates. However, on diagnosis of NEC, administration of loop diuretics may be associated with the progression of NEC severity from medical NEC to surgical NEC.

Catecholamine use is associated with enterocyte damage in critically ill patients

Small bowel damage is frequent but underdiagnosed among critically ill patients with shock. High catecholamine doses may have a deleterious effect on mesenteric blood flow. Plasma intestinal fatty acid-binding protein (I-FABP) concentration is a marker of enterocyte damage, whereas plasma citrulline concentration is a marker of functional enterocyte mass. We hypothesized that high doses of catecholamines in critically ill patients may be associated with enterocyte damage. This study aimed to determine the link between catecholamine use and dose with enterocyte damage. This is a prospective observational study performed in a large regional university teaching hospital. Critically ill patients requiring epinephrine and/or norepinephrine at admission to a medical intensive care unit (ICU) were included, as well as controls not receiving catecholamines. We evaluated at admission plasma I-FABP and citrulline concentrations, abdominal perfusion pressure (APP), and variables relating to prognosis and treatment. Patients were categorized according to the quartiles of catecholamine dose at ICU admission. Sixty critically ill patients receiving catecholamines and 27 not receiving catecholamines were included. Plasma I-FABP was higher among patients receiving catecholamine than in controls. Among patients receiving catecholamines, a dose of 0.48 γ kg min or more at ICU admission was associated with a higher I-FABP concentration. A Sepsis-related Organ Failure Assessment score higher than 11 and plasma I-FABP more than 524 pg mL at ICU admission were independently associated with 28-day mortality (odds ratio, 4.0 [1.24-12.95] and odds ratio, 4.90 [1.44-16.6], respectively). Catecholamine use is associated with I-FABP elevation in critically ill patients. Critically ill patients receiving more than 0.48 γ kg min of epinephrine and/or norepinephrine at ICU admission have high I-FABP concentrations. This suggests that enterocyte damage reflects the severity of shock, and an adverse effect of catecholamines per se is possible.

Mesenteric ischemia

PURPOSE OF REVIEW

Diagnosis of acute mesenteric ischemia in the early stages is now possible with modern computed tomography (CT), using intravenous contrast enhancement and imaging in the arterial and/or portal venous phase. The availability of CT around the clock means that more patients with acute mesenteric ischemia may be treated with urgent intestinal revascularization.

RECENT FINDINGS

The establishment of a hybrid operation room is most important to be able to perform explorative laparotomy for evaluation of the extent of mesenteric ischemia and successful intestinal revascularization. Endovascular recanalization and stenting has become an important alternative, especially in patients with both acute and chronic thrombotic superior mesenteric artery (SMA) occlusion. Aspiration embolectomy, thrombolysis and open surgical embolectomy, followed by on-table angiography, are the treatment options for embolic SMA occlusion. Endovascular therapy may be an option in the few patients with mesenteric venous thrombosis who do not respond to anticoagulation therapy. The concept of damage-control surgery is recommended after intestinal revascularization.

SUMMARY

Intestinal revascularization in patients with arterial occlusive mesenteric ischemia reduces bowel morbidity and mortality. Observational studies report that both endovascular and open vascular therapy options are effective, but endovascular technique may be preferred in these often elderly and fragile patients.

Gastro-oesophageal reflux disease increases the risk of intensive care unit admittance and mechanical ventilation use among patients with chronic obstructive pulmonary disease: a nationwide population-based cohort study

Introduction

Gastro-oesophageal reflux disease (GORD) is common among chronic obstructive pulmonary disease (COPD) patients and may have a deleterious effect on COPD prognosis. However, few studies have investigated whether GORD increases the risk of severe outcomes such as intensive care unit (ICU) admittance or mechanical ventilator use among COPD patients.

Methods

Propensity score matching by age, sex, comorbidities and COPD severity was used to match the 1,210 COPD patients with GORD sourced in this study to 2,420 COPD patients without GORD. The Kaplan-Meier method was used to explore the incidence of ICU admittance and machine ventilation with the log rank test being used to test for differences. Cox regression analysis was used to explore the risk of ICU admittance and mechanical ventilation use for patients with and without GORD.

Results

During the 12-month follow-up, GORD patients and non-GORD patients had 5.22 and 3.01 ICU admittances per 1000 person-months, and 4.34 and 2.41 mechanical ventilation uses per 1000 person-month, respectively. The log rank test revealed a difference in the incidence of ICU admittance and machine ventilation between the two cohorts. GORD was found to be an independent predicator of ICU admittance (adjusted hazard ratio (HR_adj) 1.75, 95% confidence interval (CI) 1.28-2.38) and mechanical ventilation (HR_adj 1.92, 95% CI 1.35-2.72).

Conclusion

This is the first investigation to detect a significantly higher incidence rate and independently increased risk of admission to an ICU and mechanical ventilation use among COPD patients who subsequently developed GORD during the first year following their GORD diagnosis than COPD patients who did not develop GORD.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-0849-1) contains supplementary material, which is available to authorized users.

Effects of probiotics in treatment of severe acute pancreatitis

AIM: To investigate the effects of probiotics in the treatment of severe acute pancreatitis (SAP).

METHODS: Thirty-nine SAP patients were randomly divided into two groups: a control group and a treatment group. The treatment group was given probiotics through the nasointestinal feeding tube, and the control group was given placebo (starch preparations). Infectious complications (including infected necrosis of the pancreas, pneumonia, urosepsis and bacteraemia), duration of intensive care, and rates of percutaneous drainage, intestinal ischemia and necrosis were compared between the two groups.

RESULTS: There was no significant difference (P > 0.05) in infectious complications, duration of intensive care or the rate of percutaneous drainage between the two groups, but the rate of intestinal ischemia and necrosis was significantly higher in the treatment group than in the control group.

CONCLUSION: Using probiotics does not reduce infectious complications, shorten the duration of intensive care, or reduce the rate of percutaneous drainage in patients with SAP, but increase the rate of intestinal ischemia and necrosis.

Perioperative organ injury

Despite the fact that a surgical procedure may have been performed for the appropriate indication and in a technically perfect manner, patients are threatened by perioperative organ injury. For example, stroke, myocardial infarction, acute respiratory distress syndrome, acute kidney injury, or acute gut injury are among the most common causes for morbidity and mortality in surgical patients. In the current review, the authors discuss the pathogenesis of perioperative organ injury, and provide select examples for novel treatment concepts that have emerged over the past decade. Indeed, the authors are of the opinion that research to provide mechanistic insight into acute organ injury and identification of novel therapeutic approaches for the prevention or treatment of perioperative organ injury represent the most important opportunity to improve outcomes of anesthesia and surgery.

Management of ischemic colitis

Ischemic colitis is a commonly misunderstood clinical condition. Although the colon is the most common region of ischemia in the gastrointestinal tract, many surgeons have difficulty with diagnosis and treatment of ischemic colitis. The process can occur from either occlusive vascular disease or nonocclusive disease, and can be gangrenous or nongangrenous. Differentiating gangrenous from nongangrenous disease can be a difficult clinical challenge as both sets of patients generally present with abdominal pain and bloody diarrhea. Although the majority of patients have transient ischemia with nongangrenous colitis that can be successfully managed nonoperatively, prompt recognition and surgical intervention is critical in patients with gangrenous colitis. In this article, the diagnosis and treatment of ischemic colitis is reviewed with emphasis on a systematic, evidence-based approach to management.

Retrospective analysis of disease association and outcome in histologically confirmed ischemic colitis

OBJECTIVE

To identify risk factors, clinical features and complications in patients with ischemic colitis (IC).

METHODS

All patients diagnosed with biopsy proven IC within a 2-year period were identified; clinical data were retrospectively collected and subsequently analyzed.

RESULTS

In total, 72 IC patients with a mean age of 68 years were included in this study. Among them, 18 (25.0%) were younger than 65 years with a female predominance. One-third of the patients was found to be without vascular risk factors, and 8 patients met the criteria for irritable bowel syndrome. No history of oral contraceptives or hormonal replacement therapy use could be found among the women diagnosed with IC. Over a mean duration of follow-up of 9.5 months (range 0-65 months), the rate of recurrent disease was 16.7%, while only 2 (2.8%) patients developed extra intestinal vascular sequelae. Statistical analysis identified a history of atrial fibrillation and the use of furosemide to be the only significant predictors of a poor outcome, while coronary artery disease and chronic renal failure predicted recurrence and low platelet count predicted stricture formation.

CONCLUSIONS

Although most patients with IC are elderly and have conventional vascular risk factors, it should also be considered in young patients without vascular risk factors, especially in women, who may have an atypical distribution of the disease. Severe complications and extraintestinal vascular sequelae are rare, however, residual gastrointestinal complaints and recurrent disease are relatively common and there are no reliable predictors of the outcome.

Mesenteric blood flow, glucose absorption and blood pressure responses to small intestinal glucose in critically ill patients older than 65 years

PURPOSE

To compare nutrient-stimulated changes in superior mesenteric artery (SMA) blood flow, glucose absorption and glycaemia in individuals older than 65 years with, and without, critical illness.

METHODS

Following a 1-h 'observation' period (t (0)-t (60)), 0.9 % saline and glucose (1 kcal/ml) were infused directly into the small intestine at 2 ml/min between t (60)-t (120), and t (120)-t (180), respectively. SMA blood flow was measured using Doppler ultrasonography at t (60) (fasting), t (90) and t (150) and is presented as raw values and nutrient-stimulated increment from baseline (Δ). Glucose absorption was evaluated using serum 3-O-methylglucose (3-OMG) concentrations during, and for 1 h after, the glucose infusion (i.e. t (120)-t (180) and t (120)-t (240)). Mean arterial pressure was recorded between t (60)-t (240). Data are presented as median (25th, 75th percentile).

RESULTS

Eleven mechanically ventilated critically ill patients [age 75 (69, 79) years] and nine healthy volunteers [70 (68, 77) years] were studied. The magnitude of the nutrient-stimulated increase in SMA flow was markedly less in the critically ill when compared with healthy subjects [Δt (150): patients 115 (-138, 367) versus health 836 (618, 1,054) ml/min; P = 0.001]. In patients, glucose absorption was reduced during, and for 1 h after, the glucose infusion when compared with health [AUC(120-180): 4.571 (2.591, 6.551) versus 11.307 (8.447, 14.167) mmol/l min; P < 0.001 and AUC(120-240): 26.5 (17.7, 35.3) versus 40.6 (31.7, 49.4) mmol/l min; P = 0.031]. A close relationship between the nutrient-stimulated increment in SMA flow and glucose absorption was evident (3-OMG AUC(120-180) and ∆SMA flow at t (150): r (2) = 0.29; P < 0.05).

CONCLUSIONS

In critically ill patients aged >65 years, stimulation of SMA flow by small intestinal glucose infusion may be attenuated, which could account for the reduction in glucose absorption.

Treatment of necrotizing pancreatitis

Acute pancreatitis is a common and potentially lethal disease. It is associated with significant morbidity and consumes enormous health care resources. Over the last 2 decades, the treatment of acute pancreatitis has undergone fundamental changes based on new conceptual insights and evidence from clinical studies. The majority of patients with necrotizing pancreatitis have sterile necrosis, which can be successfully treated conservatively. Emphasis of conservative treatment is on supportive measures and prevention of infection of necrosis and other complications. Patients with infected necrosis generally need to undergo an intervention, which has shifted from primary open necrosectomy in an early disease stage to a step-up approach, starting with catheter drainage if needed, followed by minimally invasive surgical or endoscopic necrosectomy once peripancreatic collections have sufficiently demarcated. This review provides an overview of current standards for conservative and invasive treatment of necrotizing pancreatitis.

[A case of idiopathic recurrent duodenojejunitis]

There are various etiologies of duodenojejunitis such as Henoch-Schönlei purpura (H-S purpura), vasculitis, Crohn's disease, celiac sprue, ischemia, lymphoma, Zollinger-Ellison syndrome, bacteria or parasite infection, radiation, drug induced jejunitis, eosinophilic jejunitis, and toxins. A 31-year-old man presented with left upper quadrant pain. He did not have febrile sense, hematochezia, melena, diarrhea, arthralgia and hematuria. He had neither drug history nor traveling history. Esophagogastroduodenoscopy showed diffuse mucosal erythema and segmental hemorrhagic erosions on the distal area to the descending portion of the duodenum and proximal jejunum, which were commonly observed in the gastrointestinal involvement of H-S purpura. However, he showed no skin lesions, joint and urologic problems until the discharge. Autoimmune markers such as antinuclear antibody and antineutrophil cytoplasmic antibody were negative. Celiac and mesenteric angiogram showed no vascular abnormality. After the administration of oral prednisolone 40 mg daily for therapeutic trial, abdominal pain and endoscopic lesions were improved. He experienced relapses of same episode without skin lesions 16 times during follow-up of 8 years, which were also treated with prednisolone. The abdominal computed tomography during the follow-up also showed no significant finding. We report a case of primary recurrent duodenojejunitis similar to the gastrointestinal involvement of H-S purpura without purpura.

Lower gastrointestinal bleeding in chronic hemodialysis patients

Gastrointestinal (GI) bleeding is more common in patients with chronic kidney disease and is associated with higher mortality than in the general population. Blood losses in this patient population can be quite severe at times and it is important to differentiate anemia of chronic diseases from anemia due to GI bleeding. We review the literature on common causes of lower gastrointestinal bleeding (LGI) in chronic kidney disease (CKD) and end-stage renal disease (ESRD) patients. We suggest an approach to diagnosis and management of this problem.

TLR4 mediates lung injury and inflammation in intestinal ischemia-reperfusion

BACKGROUND

Splanchnic ischemia is common in critically ill patients, and it can result in injury not only of the intestine but also in distant organs, particularly in the lung. Local inflammatory changes play a pivotal role in the development of acute lung injury after intestinal ischemia, but the underlying molecular mechanisms are not fully understood. We sought to examine the role of Toll-like receptor 4 (TLR4) in the mouse model of intestinal ischemia-reperfusion (I/R)-induced lung injury and inflammation.

MATERIALS AND METHODS

Adult male TLR4 mutant (C3H/HeJ) mice and TLR4 wild-type (WT) (C3H/HeOuJ) mice were subjected to 40 min of intestinal ischemia by clamping the superior mesenteric artery followed by 6 h of reperfusion. Lung histology was assessed and parameters of pulmonary microvascular permeability, inflammatory cytokine expression, and neutrophil infiltration were measured. Activation of mitogen-activated protein kinases (MAPKs) and the transcription factors nuclear factor κB (NF-κB) and activator protein-1 (AP-1) in the lungs were also detected.

RESULTS

After intestinal I/R, lungs from TLR4 mutant mice demonstrated a significantly lower histological injury, a marked reduction of epithelial apoptosis associated with the decreased level of cleaved caspase-3 and the increased ratio of Bcl-xL to Bax proteins, and a large reduction in pulmonary vascular permeability and myeloperoxidase (MPO) activity in comparison with WT mice. TLR4 mutant mice also displayed marked decreases in tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), and macrophage inflammatory protein-2 (MIP-2) expression. Following intestinal I/R, phosporylation of p38 MAPK and activation of NF-κB and AP-1 were significantly inhibited in lung tissue from TLR4 mutant mice compared with WT controls.

CONCLUSIONS

These data suggest that TLR4 plays an important role in the pathogenesis of intestinal I/R-induced acute lung injury and inflammation and that p38 kinase and NF-κB may be involved in TLR4 signaling-mediated lung inflammatory processes during intestinal I/R.

Clinical features of ischemic colitis

Ischemic colitis (IC) is the most common form of ischemic injury of the gastrointestinal tract and occurs more frequently in the elderly. It presents either as an occlusive or a non-occlusive form of intestinal ischaemia. The clinical presentation of IC is variable and non-specific. Colonoscopy is the most common diagnostic method and the golden standard for confirmation of IC. Therapy and outcome depend on the severity and complications of the disease. Most cases of the non-gangrenous form show a favorable prognosis after conservative therapy, while high mortality and urgent operative intervention are the hallmarks of gangrenous IC.

Fulminant nonocclusive mesenteric ischemia just after hip arthroplasty

Nonocclusive mesenteric ischemia (NOMI) is not a rare clinical entity in intensive medicine, and it can be a consequence of several clinical or surgical situations. This pathology results from reduced intestinal microvascular blood supply associated with an acute inflammatory process, culminating with bowel necrosis. This is a case on a female patient who developed immediate postsurgical NOMI following hip arthroplasty and died. Since diagnosis of this potentially fatal condition remains a dilemma, NOMI should always be considered an eventual postoperative complication in high-risk surgical patients such as elderly individuals with previous history of nicotine abuse, congestive heart failure, and essential hypertension. The present paper highlights the importance of early diagnosis and prompt adequate treatment of NOMI in subjects with diminished cardiac output and severe abdominal pain.