Contemporary management of acute mesenteric ischemia: Factors associated with survival

Attenuation of intestinal ischemia-reperfusion-injury by β-alanine: a potentially glycine-receptor mediated effect

BACKGROUND

Acute mesenteric ischemia is often caused by embolization of the mesenteric arterial circulation. Coherent intestinal injury due to ischemia and following reperfusion get visible on macroscopic and histologic level. In previous studies, application of glycine caused an ameliorated intestinal damage after ischemia-reperfusion in rats. Because we speculated that glycine acted here as a signal molecule, we investigated whether the glycine-receptor agonist β-alanine evokes the same beneficial effect in intestinal ischemia-reperfusion.

MATERIALS AND METHODS

β-alanine (10, 30, and 100 mg/kg) was administered intravenously. Ischemia/reperfusion of the small intestine was initiated by occluding and reopening the superior mesenteric artery in rats. After 90 min of ischemia and 120 min of reperfusion, the intestine was analyzed with regard to macroscopic and histologic tissue damage, the activity of the saccharase, and accumulation of macrophages. In addition, systemic parameters and metabolic ones (e.g., acid-base balance, electrolytes, and blood glucose) were measured at certain points in time.

RESULTS

All three dosages of β-alanine did not change systemic parameters but prevent from hyponatremia during the period of reperfusion. Most importantly, application of 100-mg β-alanine clearly diminished intestinal tissue damage, getting visible on macroscopic and histologic level. In addition, I/R-mediated decrease of saccharase activity and accumulation of macrophages in the small intestine were ameliorated.

CONCLUSIONS

The present study demonstrated that β-alanine was a potent agent to ameliorate I/R-induced injury of the small intestine. Due to its diminishing effect on the accumulation of macrophages, β-alanine is strongly expected to mediate its beneficial effect via glycine receptors.

A Review of 2255 Emergency Abdominal Operations Performed over 17 years (1996-2013) in a Gastrointestinal Surgery Unit in India

There is little information regarding the clinical spectrum and outcome of emergency abdominal operations from specialized units in India. We examined these in our gastrointestinal surgery and liver transplantation unit from a prospective database maintained between July 1996 and April 2013. Out of 9966 operations performed, 2255 (26%) were emergency procedures (reoperations during the same admission, e.g., for necrotizing pancreatitis were excluded). The primary outcome was 30-day postoperative mortality. The mean age of the patients was 47 years (range 1-107) and included the following age groups: 0-18 years (n = 105, 4.7%); 19-64 years (n = 1766, 78.3%), and >65 years (n = 384, 17.0%). The majority were males (1609, 71%), and there were 646 females (29%). The most common indications were small bowel emergencies (598, 26.5%), followed by pancreatic (417, 18.5%) and colonic (281, 12.5%) emergencies. Pancreatic operations were the second commonest in the adult and middle aged group. Colorectal operations were the second commonest in the geriatric age group (>65 years). Emergency operations for other conditions were: postoperative complications following elective operations 171 (7.5%), gastroduodenal bleeding or perforation in 144 (6.3%), and liver surgery in 93 patients (4.1%) patients. In the small bowel emergencies, 223 patients (37.2%) had primary diagnosis of adhesive obstruction, gangrene in 135 patients (22.5%), perforation in 121 patients (20%), and fistula in 56 patients (9.3%). Mesenteric venous thrombosis was found to be the primary cause of small bowel emergencies, either as a primary cause in gangrene or as a secondary cause in perforations and adhesions. The postoperative mortality after emergencies was 12.6% compared to 2% in elective procedures. Mortality was significantly higher in males (14%) than females (9.6%), p < 0.005. Category wise mortality was as follows: pancreatic surgery (n = 86, 20.6%), surgery for postoperative complications (n = 33, 19.3%), duodenal surgery (n = 18, 12.5%), small intestinal surgery (n = 68, 11.4%), and colonic surgery (n = 35, 12.45%). Emergency operations comprise a significant proportion of a GI surgical unit's workload. The mortality is greatest after pancreatic operations followed by those done for postoperative complications. Despite advances in surgical and postoperative care, emergency operations for abdominal emergencies are associated with mortality which is six times higher compared to elective procedures.

Surgery for acute exacerbation of chronic mesenteric ischemia: a case report

BACKGROUND

Chronic mesenteric ischemia (CMI) is a rare disease; however, symptomatic CMI has a risk of acute exacerbation without timely revascularization.

CASE PRESENTATION

A 54-year-old man who had had postprandial pain for 6 months was admitted to our hospital because of vomiting and diarrhea. Although the celiac and superior mesenteric arteries were occluded at the proximal portion, contrast enhancement of the bowel wall was good in contrast-enhanced computed tomography (CECT). Endoscopic examination revealed only a healed gastric ulcer and slight mucosal erosions in the colon. He was diagnosed as having acute enteritis or inflammatory digestive disease and observed with conservative therapy, which improved his acute symptoms. On hospitalization day 42, he suddenly complained of lower back pain. CECT showed abdominal free air, which indicated gastrointestinal perforation. Emergency surgery was performed for jejunum resection. Two days later, a second operation was performed for a leak in the anastomotic site of the jejunum. Necrotic change in the small intestinal serosa was also observed and required broad resection of the small intestine. He was diagnosed with acute exacerbation of CMI, and we performed surgical retrograde bypass to the gastroduodenal artery using a saphenous vein graft as the third operation. After the surgery, he was free from digestive symptoms and was discharged.

CONCLUSIONS

When patients complain of chronic and gradual digestive symptoms, we should always consider symptomatic CMI. Timely mesenteric revascularization is important for symptomatic CMI before severe complications occur.

Chronic Visceral Ischemia: Symptom-Free Survival After Open Surgical Repair

A retrospective review of patients treated with a history of chronic visceral ischemia (CVI) was made to determine primary patency of open surgical repair and estimated symptom-free survival. Patients with CVI between 1990 and 2003 were reviewed. Included were those with chronic symptoms alone (C-CVI) and acute-on-chronic symptoms (A-CVI). Data were obtained from a vascular database. Symptom-free survival and graft patency were estimated by using product limit estimates. Fifty-eight patients (13 men, 45 women; mean age: 63 years) were treated surgically for C-CVI (34 patients) and A-CVI (24 patients). All patients had postprandial abdominal pain and weight loss (mean: 17 kg). One fourth reported food fear. Preoperative imaging demonstrated disease of the superior mesenteric artery (SMA) (100%; 64% occluded), celiac axis (89%; 37% occluded), and inferior mesenteric artery (IMA) (54%; 60% occluded). Multiple vessels were involved in 95% of patients (mean: 2.3 vessels/patient). Operative management included antegrade revascularization of 80 vessels. Combined aortic and/or renal procedures were performed in 7 patients. Patient demographics and visceral disease did not differ for C-CVI and A-CVI; however, perioperative mortality differed significantly (10% for C-CVI vs 54% for A-CVI [p<0.001]). Intestinal gangrene at presentation was associated with perioperative (hazard ratio [HR]: 7.6; 95% CI: 2.7–21.6; p=0.0002) and follow-up death (HR: 7.8; CI 2.8–21.9; p< 0.0001). Follow-up (mean: 34 months) was complete for 54/68 vessels (79%). Estimated primary and primary assisted patency at 5 years were 81% and 89% respectively. Estimated symptom-free survival for hospital survivors was 57% at 70 months. Open antegrade methods of visceral artery repair for CVI were durable and associated with 57% symptom-free survival at 70 months. Patient demographics and distribution of visceral artery anatomy were similar; however, perioperative mortality for C-CVI and A-CVI differed dramatically. Improved outcomes for A-CVI require recognition and treatment of CVI before onset of intestinal gangrene.

Tolerability of Enteral Nutrition in Mechanically Ventilated Patients With Septic Shock Who Require Vasopressors

Purpose:

Enteral nutrition (EN) is often held in patients receiving vasopressor support for septic shock. The rationale for this practice is to avoid mesenteric ischemia. The objective of this study is to evaluate the tolerability of EN in patients with septic shock who require vasopressor support and determine factors associated with tolerance of EN.

Materials and Methods:

This was a single-center retrospective review of adult patients admitted to the intensive care unit with a diagnosis of septic shock and an order for EN. The primary outcome was EN tolerance. Secondary outcomes included time to initiation of EN from the start of vasopressor(s), length of stay, and mortality.

Results:

A total of 120 patients were included. Sixty-two percent of patients tolerated EN. The most common reason for intolerance of EN was gastric residuals > 250 mL (74%). No reports of mesenteric ischemia were observed. A multivariate analysis demonstrated that patients with septic shock initiating EN within 48 hours and receiving norepinephrine-equivalent doses of 0.14 μg/kg/min or less were more likely to tolerate EN.

Conclusion:

Based on our observation, early EN may be tolerated and safely administered in patients with septic shock who are adequately fluid resuscitated and receive doses of < 0.14 μg/kg/min of norepinephrine equivalents.

Endovascular Therapy for Acute Mesenteric Ischemia: an NSQIP Analysis

Acute mesenteric ischemia (AMI) continues to carry high morbidity and mortality. Endovascular strategies have been increasingly used in the management of AMI. The purpose of this study was to evaluate the impact of endovascular therapy on outcomes of patients with AMI. The National Surgical Quality Improvement Program database was queried to identify all patients requiring emergency surgical intervention for AMI. Demographics, clinical data, interventions, and outcomes were extracted. Patients were compared according to treatment (endovascular versus hybrid versus open revascularization). Over the six-year study period, a total of 439 patients were found to have AMI [27 (6.2%) endovascular, 23 (5.2%) hybrid, and 389 (88.6%) open revascularization]. A total of 16 (59.3%) patients in the endovascular group avoided laparotomy. There was a trend toward lower transfusion requirements (intraoperative transfusion: 3.7% for endovascular vs 17.4% for hybrid vs 19.3% for open, adjusted. P = 0.127) and complications in particular pneumonia (22.2% vs 39.1% vs 27.8%, respectively, Adj. P = 0.392) and sepsis (25.9% vs 21.7% vs 35.5%, adjusted P = 0.260). Endovascular therapy was associated with a 2.5-fold decrease in the risk of death [odds ratio, 95% confidence interval: 0.4 (0.2, 0.9), adjusted P = 0.018]. In this analysis of morbidity and mortality, endovascular therapy was associated with decreased need for laparotomy and a trend toward lower transfusion requirements and complications, in particular pneumonia and sepsis. Endovascular first therapy was associated with a 2.5-fold decrease in the risk of death. Further prospective evaluation of these results is warranted.

A Statewide Analysis of the Incidence and Outcomes of Acute Mesenteric Ischemia in Maryland from 2009 to 2013

Introduction

Acute mesenteric ischemia is a surgical emergency that entails complex, multi-modal management, but its epidemiology and outcomes remain poorly defined. The aim of this study was to perform a population analysis of the contemporary incidence and outcomes of mesenteric ischemia.

Methods

This was a retrospective analysis of acute mesenteric ischemia in the state of Maryland during 2009–2013 using a comprehensive statewide hospital admission database. Demographics, illness severity, comorbidities, and outcomes were studied. The primary outcome was inpatient mortality. Survivors and non-survivors were compared using univariate analyses, and multivariable logistic regression analysis was performed to evaluate risk factors for mortality.

Results

During the 5-year study period, there were 3,157,499 adult hospital admissions in Maryland. A total of 2,255 patients (0.07%) had acute mesenteric ischemia, yielding an annual admission rate of 10/100,000. Increasing age, hypercoagulability, cardiac dysrhythmia, renal insufficiency, increasing illness severity, and tertiary hospital admission were associated with development of mesenteric ischemia. Inpatient mortality was high (24%). After multivariate analysis, independent risk factors for death were age >65 years, critical illness severity, mechanical ventilation, tertiary hospital admission, hypercoagulability, renal insufficiency, and dysrhythmia.

Conclusion

Acute mesenteric ischemia occurs in approximately 1/1,000 admissions in Maryland. Patients with mesenteric ischemia have significant illness severity, substantial rates of organ dysfunction, and high mortality. Patients with chronic comorbidities and acute organ dysfunction are at increased risk of death, and recognition of these risk factors may enable prevention or earlier control of mesenteric ischemia in high-risk patients.

Update in the management of type B aortic dissection

Stanford type B aortic dissection (TBAD) is a life-threatening aortic disease. The initial management goal is to prevent aortic rupture, propagation of the dissection, and symptoms by reducing the heart rate and blood pressure. Uncomplicated TBAD patients require prompt medical management to prevent aortic dilatation or rupture during subsequent follow-up. Complicated TBAD patients require immediate invasive management to prevent death or injury caused by rupture or malperfusion. Recent developments in diagnosis and management have reduced mortality related to TBAD considerably. In particular, the introduction of thoracic stent-grafts has shifted the management from surgical to endovascular repair, contributing to a fourfold increase in early survival in complicated TBAD. Furthermore, endovascular repair is now considered in some uncomplicated TBAD patients in addition to optimal medical therapy. For more challenging aortic dissection patients with involvement of the aortic arch, hybrid approaches, combining open and endovascular repair, have had promising results. Regardless of the chosen management strategy, strict antihypertensive control should be administered to all TBAD patients in addition to close imaging surveillance. Future developments in stent-graft design, medical therapy, surgical and hybrid techniques, imaging, and genetic screening may improve the outcomes of TBAD patients even further. We present a comprehensive review of the recommended management strategy based on current evidence in the literature.

ESTES guidelines: acute mesenteric ischaemia

PURPOSE

Acute mesenteric ischaemia (AMI) accounts for about 1:1000 acute hospital admissions. Untreated, AMI will cause mesenteric infarction, intestinal necrosis, an overwhelming inflammatory response and death. Early intervention can halt and reverse this process leading to a full recovery, but the diagnosis of AMI is difficult and failure to recognize AMI before intestinal necrosis has developed is responsible for the high mortality of the disease. Early diagnosis and prompt treatment are the goals of modern therapy, but there are no randomized controlled trials to guide treatment and the published literature contains a high ratio of reviews to original data. Much of that data comes from case reports and often small, retrospective series with no clearly defined treatment criteria.

METHODS

A study group of the European Society for Trauma and Emergency Surgery (ESTES) was formed in 2013 with the aim of developing guidelines for the management of AMI. A comprehensive literature search was performed using the Medical Subject Heading (MeSH) thesaurus keywords "mesenteric ischaemia", "bowel ischaemia" and "bowel infarction". The bibliographies of relevant articles were screened for additional publications. After an initial systematic review of the literature by the whole group, a steering group formulated questions using a modified Delphi process. The evidence was then reviewed to answer these questions, and recommendations formulated and agreed by the whole group.

RESULTS

The resultant recommendations are presented in this paper.

CONCLUSIONS

The aim of these guidelines is to provide recommendations for practice that will lead to improved outcomes for patients.

Management of Acute Mesenteric Ischemia

Background:

Acute mesenteric ischemia (AMI) due to a sudden loss or decrease in blood perfusion to the mesentery represents a highly lethal condition. However, the optimal surgical management remains debatable and merits a more clear recommendation based on a higher level of evidence.

Methods:

A systematic review of articles published between 2000 and 2013 was performed. Patients were divided into endovascular treatment (ET), open surgery (OS), and hybrid technique (HT) groups. Data of patients’ demographics, procedural information, clinical outcomes including mortality, morbidity, primary patency rate, technique success, primary intestinal resection rate, and second-look laparotomy rate, and follow-up were all retrieved. Comparison between the ET and the OS groups was made using 2-sided Student t test and 2-sided χ2 test or Fisher exact test where appropriate.

Results:

Twenty-eight articles with a total of 1110 patients were included for the review. The ET group had lower in-hospital mortality and morbidity but similar survival rate during follow-up compared to the OS group. The primary patency rate was higher in the ET group. The overall bowel resection rate was lower in the ET group, and nearly every patient in the cohort who required second-look laparotomy required bowel resection. The HT group seemed to have the lowest mortality and acceptable second-look laparotomy rate and morbidity. Comparison between the HT group and other groups was not possible due to the limited number of cases available for review.

Conclusion:

Endovascular treatment may serve as a first-line therapy for select patients when there is a low suspicion for intestinal necrosis. Open surgery should be reserved for emergency conditions requiring exploratory laparotomy. Hybrid technique may be an especially effective approach for treating AMI, with low morbidity and mortality, although further studies are required comparing it to OS and ET.

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.

Spontaneous Intramural Intestinal Hemorrhage versus Acute Mesenteric Ischemia by CT Evaluation

Objective The purpose of our study was to differentiate the imaging findings of patients with spontaneous intramural intestinal hemorrhage (SIIH) from those with acute mesenteric ischemia (AMI) after abdominal computed tomography (CT) survey in the emergency department. Methods We retrospectively included 83 patients diagnosed with SIIH or AMI after abdominal CT. Results The mean ages of 30 SIIH patients and 53 AMI patients were 74.4±14.6 years and 75.8±11.2 years, respectively. Patients with SIIH had significantly thicker maximal intestinal wall thickening (14.8±3.9 vs. 10.9 ±4.1, p<0.001), a lower rate of ileum involvement (26.7% vs. 77.4%, p<0.001) and a higher rate of ascites (96.7% vs. 64.2%, p<0.001) compared with patients with AMI. Neither pneumatosis intestinalis (p<0.001) nor portomesenteric gas (p<0.01) were detected in SIIH patients but were observed in AMI patients. A receiver-operating characteristic (ROC) curve analysis showed that the optimal cut-off value for maximal intestinal wall thickening between groups was 10.4 mm and the area under the ROC curve between groups was 0.752 (p<0.0001). A multiple logistic regression analysis showed that the independent predictors of SIIH were non-involvement of the ileum (odds ratio, OR, 6.998; p=0.001), maximal intestinal wall thickening ≥10.4 mm (OR, 5.748; p=0.040) and ascites (OR, 13.348; p=0.023). The area under the ROC curve for the model was 0.854 (p<0.001). Conclusion The independent predictors of SIIH from AMI after abdominal CT in acute abdominal patients include non-involvement of the ileum, intestinal wall thickening ≥10.4 mm, and ascites.

Debate: Whether an endovascular-first strategy is the optimal approach for treating acute mesenteric ischemia

Acute mesenteric ischemia continues to be a life-threatening insult in often-elderly patients with many comorbidities. Recognition and correct diagnosis can be an issue leading to delays in therapy that result in loss of bowel or life, or both. The basic surgical principals in treating acute mesenteric ischemia have long been early recognition, resuscitation, urgent revascularization, resection of necrotic bowel, and reassessment with second-look laparotomies. Endovascular techniques now offer a less invasive alternative, but whether an endovascular-first or open surgery-first approach is preferred in most patients is unclear. Our discussants will attempt to clarify these issues.

Isolated Large Cell Calcifying Sertoli Cell Tumor in a Young Boy, not Associated with Peutz-Jeghers Syndrome or Carney Complex

BACKGROUND

Large cell calcifying sertoli cell tumor (LCCSCT) is an exceedingly rare lesion of the testicle. It is most often seen in patients with Carney complex (CNC) or Peutz-Jeghers syndrome (PJS). We now report the first pediatric patient with what appears to be bilateral LCCSCT and no other conditions or a genetic syndrome, such as PJS or CNC, have been associated with it.

METHODS

A 10-year-old boy was found to have a right testicular mass during a routine pediatric examination; he underwent right orchiectomy. He was then evaluated clinically for PJS or CNC and underwent genetic testing. His tumor was studied by immunohistochemistry for the expression of calretinin, NY-ESO-1, inhibin, CD99, S100, PLAP, AE1/AE3, Bcl-2, p53, and Mib1.

RESULTS

Patient did not have clinical features or genetic abnormalities of CNC and PJS. Microscopic features showed large, round or cubical intratubular and aggregated tumor cells with prominent nuclear atypia, large and prominent nucleoli and extensive calcification. In the Immunohistochemical studies, calretinin and inhibin alpha were up regulated in LCCSCT as compared to the adjacent benign Sertoli cells. Meanwhile, NY-ESO-1 and CD99 were down-regulated in LCCSCT. Focally and weakly positive S100 was found in the tumor tissue, but no S100 expression was present in the adjacent Sertoli cells. There was no expression of PLAP, P53, Bcl-2, Mib1 and AE1/AE3 in LCCSCT and adjacent Sertoli cells. Micro-calcifications were found in the other gonad by ultrasonography, suggesting LCCSCT.

CONCLUSION

LCCSCT is a rare testicular neoplasm, and may present in isolated rather than in more typical association with syndromes such as CNC and PJS.

Transcatheter thrombolysis combined with damage control surgery for treatment of acute mesenteric venous thrombosis associated with bowel necrosis: a retrospective study

OBJECTIVE

This study aims to evaluate the clinical outcomes of transcatheter thrombolysis in acute superior mesenteric venous thrombosis (ASMVT) associated with bowel necrosis.

METHODS

A retrospective study of six patients with ASMVT treated with catheter-directed thrombectomy/thrombolysis and damage control surgery at Jinling Hospital (Nanjing, China) between 2010 and 2013 was conducted. Demographics, past medical history, risk factors, therapeutic methods and effects, mortality, and follow-up of the study population were assessed.

RESULTS

Five of six patients underwent arteriovenous combined thrombolysis, while one patient underwent arterial thrombolysis. All patients required damage control surgery, and four of these patients underwent temporary abdominal closure. All patients survived and were free of recurrence.

CONCLUSIONS

Transcatheter thrombectomy/thrombolysis and damage control surgery could help avoid extensive bowel resection, prevent short bowel syndrome and reduce mortality for critically ill patients with acute mesenteric venous thrombosis associated with bowel necrosis.

Refractory Abdominal Pain in a Hemodialysis Patient

Nonocclusive mesenteric ischemia (NOMI) is a rare disorder. Failure of an early diagnosis may cause progressive intestinal ischemia, leading to abdominal pain, sepsis, and death. Patients with end-stage renal disease are among the highest risk populations for developing this lethal complication. The key to a correct diagnosis at an early stage is a high index of suspicion in predisposed patients. In our case, we present a 62-year-old female undergoing maintenance hemodialysis for 8 years; she complained of abdominal pain after hemodialysis in the last 3 months; NOMI was suspected after a CT angiography. She partially recovered after multiple clinical interventions such as decreased ultrafiltration, an increased dose of low molecular-weight heparin and the use of vasoactive drugs. In conclusion, NOMI can be reversible if it is diagnosed as early as possible and after the necessary diagnostic measurements are initiated.

Revascularization of acute mesenteric ischemia after creation of a dedicated multidisciplinary center

OBJECTIVE

Arterial acute mesenteric ischemia (AAMI) is a vascular and gastroenterologic emergency, most often surgical, still associated with a poor prognosis and frequent short bowel syndrome in survivors. We report the results of revascularization in AAMI patients after the creation of an intestinal stroke center.

METHODS

Since July 2009, we developed a multimodal and multidisciplinary management for AMI, focusing on intestinal viability and involving gastroenterologists, vascular and abdominal surgeons, radiologists, and intensive care specialists. This management was the first step to the creation of an intestinal stroke center, based on the stroke unit model. All patients received: (1) a specific medical protocol; (2) endovascular and/or open surgical revascularization whenever possible; and/or (3) resection of non-viable small bowel. We aimed to study survival, morbidity, type of revascularization, and bowel resection in patients who benefited from arterial revascularization in our intestinal stroke center.

RESULTS

Eighty-three patients with AMI were prospectively enrolled in the intestinal stroke center. Among them, 29 patients with AAMI underwent revascularization. The mean age was 50.2 ± 12 years, with 41% of male gender. The mean follow-up was 22.7 ± 19 months. Overall 2-year survival was 89.2%, and 30-day operative mortality was 6.9%. Surgical revascularization included bypass grafting (65%), endarterectomy with patch angioplasty (21%) ± retrograde open mesenteric stenting of the superior mesenteric artery (7%), and endovascular revascularization as first stage procedure (38%). The 2-year primary patency rate of open revascularization was 88%. The rate and the median length of bowel resected were 24% and 43 cm (range, 36-49 cm), respectively.

CONCLUSIONS

In our experience, revascularization of AAMI patients as part of a multidisciplinary and multimodal management leads to encouraging results. Vascular surgeons have a central role in a dedicated intestinal stroke center.

Percutaneous Aspiration Embolectomy Using Guiding Catheter for the Superior Mesenteric Artery Embolism

OBJECTIVE

To evaluate the technical feasibility and clinical outcome of percutaneous aspiration embolectomy for embolic occlusion of the superior mesenteric artery (SMA).

MATERIALS AND METHODS

Between January 2010 and December 2013, 9 patients with embolic occlusion of the SMA were treated by percutaneous aspiration embolectomy in 2 academic teaching hospitals. The aspiration embolectomy procedure was performed with the 6-Fr and 7-Fr guiding catheter. Thrombolysis was performed with urokinase using a multiple-sidehole infusion catheter. The clinical outcome was investigated retrospectively.

RESULTS

Superior mesenteric artery occlusion was initially diagnosed by computed tomography (CT) in all patients, and all patients had no obvious evidence of bowel infarction on CT scan. Percutaneous aspiration embolectomy was primarily performed in 6 patients, and thrombolysis was initially performed in 3 patients. In 3 patients who received primary thrombolysis, percutaneous aspiration was undertaken because the emboli were resistant to urokinase. Complete angiographic success was achieved in 6 patients and partial angiographic success was accomplished in 3 patients. One patient underwent bowel resection. One patient died of whole bowel necrosis and sepsis, and 8 patients survived without complications.

CONCLUSION

Percutaneous aspiration embolectomy is a useful tool in recanalization of embolic occlusion of the SMA in select patients.

Mortality after acute primary mesenteric infarction: a systematic review and meta-analysis of observational studies

AIM

The primary aim of this study was to determine whether the in-hospital mortality for acute mesenteric infarction has reduced in the last decade. The secondary aim was to determine if there was a statistical difference in mortality between patients having acute primary mesenteric infarction due to different causes.

METHOD

A literature search was performed of PubMed, Ovid (Embase) and Google Scholar databases. Studies on acute mesenteric infarction of primary vascular pathology were included for pooled analyses while studies that had reported comparative mortality between arterial, venous and non-occlusive mesenteric infarction (NOMI) were included in meta-analyses. Their quality was assessed using the National Institute for Health and Care Excellence assessment scale. Odds ratios (ORs) of mortality were calculated using a Mantel-Haenszel random effect model.

RESULTS

The total number of patients was 4527 and the male/female ratio was 1912/2247. The pooled in-hospital mortality was 63%. There was no significant reduction of in-hospital mortality rate in the last decade (P = 0.78). There was a significant difference in in-hospital mortality between acute arterial mesenteric infarction (73.9%) compared with acute venous mesenteric infarction (41.7%) [OR 3.47, confidence interval (CI) 2.43-4.96, P < 0.001] and NOMI (68.5%) compared with acute venous mesenteric infarction (44.2%) (OR 3.2, CI 1.83-5.6, P < 0.001). There was no difference in mortality between acute arterial mesenteric infarction and NOMI (OR 1.08, CI 0.57-2.03, P = 0.82).

CONCLUSION

In-hospital mortality rate has not changed in the last decade. Patients with arterial mesenteric infarction or with NOMI are over three times more likely to die during the first hospital admission compared with those with venous mesenteric infarction.

Long-term prognosis and a prediction model for acute bowel ischaemia following cardiac surgery

OBJECTIVES

Bowel ischaemia following cardiac surgery is associated with a high postoperative mortality. No scoring system exists as yet to predict this complication following surgery. In addition, the long-term survival is not known. We sought to evaluate in-hospital outcomes and long-term outcomes in bowel ischaemia following cardiac surgery. We also sought to devise a simple risk prediction model for this catastrophic entity.

METHODS

This was a retrospective study of data entered prospectively into our cardiac surgical database between July 1999 and May 2014. We compared the short- and long-term outcomes of patients who developed bowel ischaemia following cardiac surgery with those who did not develop bowel ischaemia using propensity-matched analysis. We developed a prediction model for bowel ischaemia from logistic regression.

RESULTS

In total, 13 853 patients underwent cardiac surgery. Of these, 85 had confirmed bowel ischaemia following surgery. The in-hospital mortality rate for those with bowel ischaemia was 60%, while in those without bowel ischaemia, the mortality rate was 3% (P < 0.0001). In those bowel ischaemia patients who had a laparotomy for corrective surgery, the in-hospital mortality was significantly less compared with those who did not have a laparotomy (39.2 vs 91.2%, P < 0.0001). The long-term survival for bowel ischaemia at 2, 6 and 10 years was 35% (±5), 31% (±5) and 26% (+/6), respectively. Multivariable analysis revealed that advanced age at surgery, peripheral vascular disease, intra-aortic balloon pump usage, NYHA IV and postoperative atrial fibrillation were the significant (P < 0.005) determinants of developing postoperative bowel ischaemia. We developed a model to predict bowel ischaemia and validated it within our population (c-index = 0.781).

CONCLUSIONS

We have shown that whilst bowel ischaemia carries a higher short-term mortality, the long-term mortality is not significantly greater for those few who survive to discharge. We have developed a simple prediction model to identify those at high risk of developing bowel ischaemia following cardiac surgery in order to optimize perioperative strategies in future.

Serum value of procalcitonin as a marker of intestinal damages: type, extension, and prognosis

BACKGROUND

Ischemic and necrotic damages are complications of digestive diseases and require emergency management. Nevertheless, the decision to surgically manage could be delayed because of no sufficiently preoperative accurate marker of ischemia diagnosis, extension, and prognosis.

METHODS

The aim of this study was to assess the predictive value of serum procalcitonin (PCT) levels for diagnosing intestinal necrotic damages, their extension, and their prognosis in patients with ischemic disease including ischemic colitis and mesenteric infarction by a gray zone approach. Between January 2007 to June 2014, 128 patients with ischemic colitis and mesenteric infarction (codes K55.0 and K51.9) were operated, for whom data on PCT were available. We perform a retrospective, multicenter review of their medical records. Patients were divided into subgroups: ischemia (ID group) versus necrosis (ND group); the extension [focal (FD) vs. extended (ED)] and the vital status [deceased (D) vs. alive (A)].

RESULTS

PCT levels were higher in the ND (n = 94; p = 0.009); ED (n = 100; p = 0.02); and D (n = 70; p = 0.0003) groups. With a gray zone approach, the predictive thresholds were (i) for necrosis 2.473 ng/mL, (ii) for extension 3.884 ng/mL, and (iii) for mortality 7.87 ng/mL.

CONCLUSION

In our population, PCT could be used as a marker of necrosis; especially in case of extended damages and reflects the patient's prognosis.

Plasma biomarkers for early diagnosis of acute intestinal ischemia

Determining the severity of acute mesenteric ischemia or reperfusion injury can be problematic, as early visceral hypoperfusion is difficult to detect by traditional laboratory testing. Likewise gauging the success of resuscitation and therapeutic intervention is also challenging to determine by laboratory analysis alone. Investigators continue to actively search for plasma biomarkers that will aide clinicians in identifying the early microvascular changes associated with visceral splanchnic malperfusion in an effort to allow for earlier diagnosis and expedient intervention in order to minimize overall intestinal ischemia and reperfusion injury for the potential of improving clinical outcomes.

Early enteral nutrition in critically ill patients with hemodynamic instability: an evidence-based review and practical advice

Early enteral nutrition (EEN) in critically ill patients is associated with significant benefit as well as elevated risk of complications. Concomitant use of EEN with vasopressors has been associated with nonocclusive bowel necrosis in critically ill patients with hemodynamic instability. The decision when to initiate enteral nutrition in hemodynamically unstable patients that require vasoactive substances remains a clinical dilemma. This review summarizes the effect of EEN and vasoactive agents on gastrointestinal blood flow and perfusion in critically ill patients, based on current evidence. Animal and clinical data involving simultaneous administration of EEN and vasoactive agents for hemodynamic instability are reviewed, and the factors related to the safety and effectiveness of EEN support in this patient population are analyzed. Moreover, practical recommendations are provided. Additional randomized clinical trials are warranted to provide cutting-edge evidence-based guidance about this issue for practitioners of critical care.

The length of necrosis and renal insufficiency predict the outcome of acute mesenteric ischemia

BACKGROUND

Acute mesenteric ischemia (AMI) is a potentially life-threatening condition because of its diagnostic difficulty, operative challenges, and comorbidities a patient may have. The aim of this study was to identify factors associated with adverse outcomes in patients with AMI.

METHODS

The hospital records and clinical data of all patients with AMI were reviewed for a recent 4-year period. Clinical outcomes and factors influencing mortality were analyzed.

RESULTS

Included in the study were 104 patients (46 females and 58 males) with an overall mean age of 66 ± 13.4 years. The cause of AMI was arterial pathology in 74 (71%) patients, venous thrombosis in 15 (14%) patients, and nonocclusive ischemia in 12 (12%) patients. Abdominal pain was the most common presenting symptom (97% of patients). The 30-day mortality rate was 66%. Univariate analysis showed that mortality was associated with renal insufficiency (p = 0.004), an age greater than 70 years (p = 0.02), the presence of comorbidities (p = 0.001), a leukocyte count greater than 18,000/mL (p = 0.04), and small bowel necrosis of more than 100 cm (p < 0.0001). Logistic regression analysis showed that independent predictors of mortality were small bowel necrosis of more than 100 cm (p = 0.002) and a serum creatinine level greater than 2 mg/dL (p = 0.04).

CONCLUSION

The length of the necrosis and renal insufficiency are the primary factors that result in a poor outcome in AMI patients. Prompt diagnostic evaluation and early therapeutic interventions may help to prevent the development of these fatal predictors.

Impaired intestinal mucosal barrier upon ischemia-reperfusion: "patching holes in the shield with a simple surgical method"

Mesenteric ischemia-reperfusion (IR) is associated with impairment of the gut barrier function and the initiation of a proinflammatory cascade with life-threatening results. Therefore methods directed to ameliorate IR injury are of great importance. We aimed at describing the effects of postconditioning (PC) on the alterations of the intestinal mucosal function and the inflammatory response upon mesenteric IR. Methods. Male Wistar rats were gavaged with green fluorescent protein-expressing E. coli suspensions. Animals were randomized into three groups (n = 15), sham-operated, IR-, and PC-groups, and underwent 60 minutes of superior mesenteric artery occlusion, followed by 6 hours of reperfusion. Postconditioning was performed at the onset of reperfusion. Blood and tissue samples were taken at the end of reperfusion, for histological, bacteriological, and plasma examinations. Results. The PC-group presented a more favorable claudin-2, claudin-3, claudin-4, and zonula occludens-1 membrane expression profile, and significantly lower rates of bacterial translocation to distant organs and plasma D-lactate levels compared to the IR-group. Histopathological lesions, plasma I-FABP, IL-6, and TNF-α levels were significantly lower in the PC-group compared to the IR-group. Conclusion. The use of postconditioning improved the integrity of the intestinal mucosal barrier upon mesenteric IR, and thus reduced the incidence of bacterial translocation and development of a systemic inflammatory response.

Retrograde open mesenteric stenting for acute mesenteric ischemia

OBJECTIVE

Acute mesenteric ischemia (AMI) encompasses the sequels of end-stage untreated chronic mesenteric ischemia and acute mesenteric artery thrombosis. Percutaneous mesenteric artery stenting (PMAS) is the preferred treatment of patients with AMI but is not always feasible. Retrograde open mesenteric stenting (ROMS) is a hybrid technique that combines the advantages of open surgical and endovascular approaches. The literature on the results of this new technique is scarce. The aim of this study was to evaluate the results of ROMS in a consecutive series of patients with AMI.

METHODS

All patients with emergent mesenteric revascularization for AMI between January 2007 and September 2011 were entered in our prospective registry. Technical success, mortality, patency, clinical success, and complication rate at 30 days and 6 and 12 months were assessed.

RESULTS

Sixty-eight patients presented with AMI and 54 underwent PMAS, of which four were unsuccessful and followed by ROMS. Eleven patients were directly treated with ROMS, making a total of 15 patients (10 women and five men; median age, 66 years [interquartile range, 54-73 years]). In all patients, only the superior mesenteric artery was revascularized. In nine of the 15 patients, all three mesenteric arteries were severely stenotic or occluded. Technical success was achieved in 14 patients. At ROMS in two patients, the small bowel was severely ischemic. One of these patients needed a partial bowel resection because of irreversible transmural ischemia. At 30 days, the mortality rate was 20% and the primary patency was 92%. Ten patients underwent unplanned relaparotomy, of whom one needed resection of a large part of the small bowel. At 12 months, the mortality rate was still 20%. The primary patency was 83%. Primary assisted patency was 91%, and secondary patency was 100%. Clinical success at 30 days, 6 months, and 12 months, respectively, was 73%, 67%, and 67%.

CONCLUSIONS

AMI is still a devastating event. If PMAS is not feasible, ROMS is a reliable alternative and is associated with a relatively low mortality and morbidity rate.

Investigating viability of intestine using spectroscopy: a pilot study

BACKGROUND

The differentiation of "viable" from "nonviable" bowel remains a challenge in the treatment of acute mesenteric ischemia. In this study, diffuse reflectance spectroscopy (DRS) was used to investigate the viability of bowel tissue after ischemia and reperfusion in an animal model in vivo and in real time.

METHODS

A total of 25 females Sprague-Dawley rats were divided into five groups based on different bowel ischemia times. In each study group for four of them, the superior mesenteric artery was occluded using a vascular clamp for a different period (i.e., 30, 45, 60, and 90 min; n = 5 for each group). Intestinal reperfusion was accomplished by releasing the clamps after the given occlusion period for each group. Spectra were acquired by gently touching the optical fiber probe to the bowel tissue before the induce ischemia, at the end of the induced ischemia, and after the reperfusion. The data acquired before the ischemia were used as a control group. Without occluding the superior mesenteric artery, the spectra were acquired on the bowel with the same time intervals of the experiments were used as a sham group (n = 5). Subsequently, the same bowel segments were sent for histopathologic examination.

RESULTS

Based on the correlation between the spectra acquired from the bowel segments and the results from the histopathologic investigation, DRS is able to differentiate the histopathologic grading that appears when the Chiu/Park score ≥5 (i.e., high-level ischemic injury) than Chiu/Park score <5. Eight out of nine low-level ischemic injury tissue samples were correctly defined using the spectroscopic classification system. All eleven high-level ischemic injury tissues that were histopathologically assigned grade 5 and above were correctly defined using the spectroscopic classification system in the ischemia-reperfusion groups.

CONCLUSIONS

DRS could potentially be used intraoperatively for the assessment of bowel viability in real time. These preliminary findings suggest that DRS has the potential to reduce unnecessary resection of viable tissue or insufficient resection of nonviable tissues may reduce the mortality and morbidity rates of intestinal ischemia-reperfusion as acute mesenteric ischemia.

Acute Mesenteric Ischaemia-An Indian Perspective

In Western countries, acute mesenteric ischaemia is commonly due to arterial occlusion and occurs in patients who are usually in their seventh decade. A venous cause for intestinal gangrene has been reported in only about 10 %. We examined whether this was so in India and compared the clinical features of patients with mesenteric arterial and venous ischaemia and relate these to their ultimate prognosis. We studied retrospectively, the records of all patients admitted or referred to the department with a diagnosis of acute mesenteric ischaemia between January 1997 and October 2012, noting their demographic details and mode of presentation, the results of preoperative imaging and blood investigations, the extent of bowel ischaemia, and the length of bowel that was resected at operation and their outcome. There were 117 patients, 85 males and 32 females whose median age was 53 years. Mesenteric venous thrombosis was seen in 56 patients (48 %) and mesenteric arterial occlusion in 61 (52 %). Forty six patients died (39 %); 15 with venous occlusion (27 %) and 31 with arterial occlusion (51 %). Compared to patients with arterial occlusion, the patients with venous obstruction were younger, had a longer duration of symptoms, were less frequently hypotensive at presentation, had higher platelet counts, had a shorter length of bowel resected, had fewer colonic resections and had a lower mortality. Other predictors of mortality on multivariate analysis were a longer duration of symptoms, lower serum albumin and higher creatinine levels at presentation and a shorter length of residual bowel. In India, acute mesenteric ischaemia in tertiary care centres is due to venous thrombosis in almost half of the patients who are at least a decade younger than those in the West. Significant predictors of mortality include low serum albumin and raised creatinine levels, a shorter residual bowel length and an arterial cause for mesenteric ischaemia.

Ileocolic to right iliac arterial transposition for the treatment of chronic mesenteric ischemia

The treatment of chronic mesenteric ischemia remains challenging and controversy exists over the best interventional option. Endovascular treatment has emerged as first-line management due to its associated lower morbidity and mortality than surgical reconstruction. However, open mesenteric reconstructions continue to play an important role in patients with lesions that are unsuitable for an endovascular option. Mesenteric operations utilize the aorta or iliac artery as the inflow source for a vein or prosthetic bypass to the celiac artery or superior mesenteric artery. We describe an exceptional case of chronic mesenteric ischemia due to atherosclerosis that was treated successfully with a novel ileocolic to right iliac arterial transposition.

Hypothermia and the acute abdomen

A 64-year old man presented to A&E with a 24 h history of persistent hypothermia and increasing confusion. His medical history included congestive heart failure, hypertension and intermittent claudication secondary to distal abdominal aortic occlusion. Examination revealed profound hypothermia-31°C, bilateral reduced power in the lower limbs and no palpable peripheral pulses. Initial blood tests revealed a metabolic acidosis with hyperlactactaemia, neutrophilia and deranged electrolytes. CT scan of the abdomen revealed extensive thromboemobolic disease of the abdominal arterial tree and diagnosed acute mesenteric ischaemia. The patient was taken to theatre where an emergency laparotomy demonstrated a perforated duodenum, which was subsequently patched, followed immediately by an axillofemoral bypass with subsequent femoral-femoral crossover. Sadly, the patient passed away shortly after completion of surgery.

The effect of silymarin on mesenteric ischemia-reperfusion injury

OBJECTIVE

To examine the effect of silymarin (SM), a mixture of flavonoids and polyphenols extracted from Silybum marianum, on mesenteric ischemia-reperfusion (I-R) injury in a rat model.

MATERIALS AND METHODS

Fifty rats were randomly divided into 5 groups (n = 10). Group 1 was sham operated, while groups 2-5 were subjected to mesenteric I-R lasting 1 h. Group 2 received isotonic sodium chloride, group 3 received SM (100 mg/kg/day) for 7 days before I-R, group 4 received SM for 7 days after I-R, and group 5 received SM for 7 days both before and after I-R. The rats were sacrificed by exsanguination in groups 1-3 at the 24th hour and groups 4 and 5 were sacrificed on the 7th day of reperfusion. Blood and intestinal specimens were taken for biochemical and pathological evaluations.

RESULTS

Serum superoxide dismutase (SOD) and heat shock protein 70 levels were significantly higher in group 2 (5.24 ± 1.76 U/l and 261.4 ± 16.8 ng/ml) compared to the sham group (2.08 ± 1.76 U/l and 189.9 ± 28.7 ng/ml) (p < 0.001 and p < 0.0001, respectively). However, SOD activity and the extent and severity of the histopathological lesions were significantly less in groups 3 [3.11 ± 1.18 U/l, 1.0 (range 0.0-2.0)], 4 [2.15 ± 0.87 U/l, 1.0 (range 1.0-3.0)], and 5 [1.80 ± 0.61 U/l, 0.5 (range 0.0-2.0)], treated with SM, than in group 2 [5.24 ± 1.76 U/l, 2.0 (range 2.0-3.0)] (p = 0.002, p < 0.001, and p = 0.0001; p < 0.001, p = 0.007, and p = 0.0001, respectively). Also, TNF-α levels were lower in the SM-supplemented groups compared to group 2. Serum thiobarbituric acid-reactive substance concentrations were low in the pre-/posttreatment groups treated with SM compared to group 2. No statistical difference was observed for protein carbonyls between the groups.

CONCLUSION

Our findings suggest that SM therapy may attenuate the oxidative and intestinal damage induced by I-R injuries.

Heparin-binding EGF-like growth factor (HB-EGF) therapy for intestinal injury: Application and future prospects

Throughout the past 20 years, we have been investigating the potential therapeutic roles of heparin-binding EGF-like growth factor (HB-EGF), a member of the epidermal growth factor family, in various models of intestinal injury including necrotizing enterocolitis (NEC), intestinal ischemia/reperfusion (I/R) injury, and hemorrhagic shock and resuscitation (HS/R). Our studies have demonstrated that HB-EGF acts as an effective mitogen, a restitution-inducing reagent, a cellular trophic factor, an anti-apoptotic protein and a vasodilator, via its effects on various cell types in the intestine. In the current paper, we have reviewed the application and therapeutic effects of HB-EGF in three classic animal models of intestinal injury, with particular emphasis on its protection of the intestines from NEC. Additionally, we have summarized the protective functions of HB-EGF on various target cells in the intestine. Lastly, we have provided a brief discussion focusing on the future development of HB-EGF clinical applications for the treatment of various forms of intestinal injury including NEC.

Comparison of open and endovascular treatment of acute mesenteric ischemia

INTRODUCTION

Acute mesenteric ischemia (AMI) is a commonly fatal result of inadequate bowel perfusion that requires immediate evaluation by both vascular and general surgeons. Treatment often involves vascular repair as well as bowel resection and the possible need for parenteral nutrition. Little data exist regarding the rates of bowel resection following endovascular vs open repair of AMI.

METHODS

Using the National Inpatient Sample database, admissions from 2005 through 2009 were identified according to International Classification of Diseases, Ninth Revision codes correlating to both AMI (557.0) and subsequent vascular intervention (39.26, 38.16, 38.06, 39.9, 99.10). Patients with a diagnosis of AMI but no intervention or nonemergent admission status were excluded. Patient level data regarding age, gender, and comorbidities were also examined. Outcome measures included mortality, length of stay, the need for bowel resection (45.6, 45.71-9, 45.8), or infusion of total parenteral nutrition (TPN; 99.10) during the same hospitalization. Statistical analysis was conducted by χ(2) tests and Wilcoxon rank-sum comparisons.

RESULTS

Of 23,744 patients presenting with AMI, 4665 underwent interventional treatment from 2005 through 2009. Of these patients, 57.1% were female, and the mean age was 70.5 years. A total of 679 patients underwent vascular intervention; 514 (75.7%) underwent open surgery and 165 (24.3%) underwent endovascular treatment overall during the study period. The proportion of patients undergoing endovascular repair increased from 11.9% of patients in 2005 to 30.0% in 2009. Severity of comorbidities, as measured by the Charlson index, did not differ significantly between the treatment groups. Mortality was significantly more commonly associated with open revascularization compared with endovascular intervention (39.3% vs 24.9%; P = .01). Length of stay was also significantly longer in the patient group undergoing open revascularization (12.9 vs 17.1 days; P = .006). During the study time period, 14.4% of patients undergoing endovascular procedures required bowel resection compared with 33.4% for open revascularization (P < .001). Endovascular repair was also less commonly associated with requirement for TPN support (13.7% vs 24.4%; P = .025).

CONCLUSIONS

Endovascular intervention for AMI had increased significantly in the modern era. Among AMI patients undergoing revascularization, endovascular treatment was associated with decreased mortality and shorter length of stay. Furthermore, endovascular intervention was associated with lower rates of bowel resection and need for TPN. Further research is warranted to determine if increased use of endovascular repair could improve overall and gastrointestinal outcomes among patients requiring vascular repair for AMI.

The diagnosis of acute mesenteric ischemia: A systematic review and meta-analysis

OBJECTIVES

Acute mesenteric ischemia is an infrequent cause of abdominal pain in emergency department (ED) patients; however, mortality for this condition is high. Rapid diagnosis and surgery are key to survival, but presenting signs are often vague or variable, and there is no pathognomonic laboratory screening test. A systematic review and meta-analysis of the available literature was performed to determine diagnostic test characteristics of patient symptoms, objective signs, laboratory studies, and diagnostic modalities to help rule in or out the diagnosis of acute mesenteric ischemia in the ED.

METHODS

In concordance with published guidelines for systematic reviews, the medical literature was searched for relevant articles. The Quality Assessment Tool for Diagnostic Accuracy Studies-2 (QUADAS-2) for systematic reviews was used to evaluate the overall quality of the trials included. Summary estimates of diagnostic accuracy were computed by using a random-effects model to combine studies. Those studies without data to fully complete a two-by-two table were not included in the meta-analysis portion of the project.

RESULTS

The literature search identified 1,149 potentially relevant studies, of which 23 were included in the final analysis. The quality of the diagnostic studies was highly variable. A total of 1,970 patients were included in the combined population of all included studies. The prevalence of acute mesenteric ischemia ranged from 8% to 60%. There was a pooled sensitivity for l-lactate of 86% (95% confidence interval [CI] = 73% to 94%) and a pooled specificity of 44% (95% CI = 32% to 55%). There was a pooled sensitivity for D-dimer of 96% (95% CI = 89% to 99%) and a pooled specificity of 40% (95% CI = 33% to 47%). For computed tomography (CT), we found a pooled sensitivity of 94% (95% CI = 90% to 97%) and specificity of 95% (95% CI = 93% to 97%). The positive likelihood ratio (+LR) for a positive CT was 17.5 (95% CI = 5.99 to 51.29), and the negative likelihood ratio (-LR) was 0.09 (95% CI = 0.05 to 0.17). The pooled operative mortality rate for mesenteric ischemia was 47% (95% CI = 40% to 54%). Given these findings, the test threshold of 2.1% (below this pretest probability, do not test further) and a treatment threshold of 74% (above this pretest probability, proceed to surgical management) were calculated.

CONCLUSIONS

The quality of the overall literature base for mesenteric ischemia is varied. Signs, symptoms, and laboratory testing are insufficiently diagnostic for the condition. Only CT angiography had adequate accuracy to establish the diagnosis of acute mesenteric ischemia in lieu of laparotomy.

Acute mesenteric ischemia after cardiac surgery: an analysis of 52 patients

OBJECTIVE

Acute mesenteric ischemia (AMI) is a rare but serious complication after cardiac surgery. The aim of this retrospective study was to evaluate the incidence, outcome, and perioperative risk factors of AMI in the patients undergoing elective cardiac surgery.

METHODS

From January 2005 to May 2013, all patients who underwent cardiac surgery were screened for participation, and patients with registered gastrointestinal complications were retrospectively reviewed. Univariate analyses were performed.

RESULTS

The study included 6013 patients, of which 52 (0.86%) patients suffered from AMI, 35 (67%) of whom died. The control group (150 patients) was randomly chosen from among cases undergoing cardiopulmonary bypass (CPB). Preoperative parameters including age (P = 0.03), renal insufficiency (P = 0.004), peripheral vascular disease (P = 0.04), preoperative inotropic support (P < 0.001), poor left ventricular ejection fraction (P = 0.002), cardiogenic shock (P = 0.003), and preoperative intra-aortic balloon pump (IABP) support (P = 0.05) revealed significantly higher levels in the AMI group. Among intra- and postoperative parameters, CPB time (P < 0.001), dialysis (P = 0.04), inotropic support (P = 0.007), prolonged ventilator time (P < 0.001), and IABP support (P = 0.007) appeared significantly higher in the AMI group than the control group.

CONCLUSIONS

Prompt diagnosis and early treatment should be initiated as early as possible in any patient suspected of AMI, leading to dramatic reduction in the mortality rate.

Gastro-intestinal vascular emergencies

Gastro-Intestinal Vascular Emergencies include all digestive ischaemic injuries related to acute or chronic vascular and/or haemodynamic diseases. Gastro-intestinal ischaemic injuries can be occlusive or non-occlusive, arterial or venous, localized or generalized, superficial or transmural and share the risks of infarction, organ failure and death. The diagnosis must be suspected, at the initial presentation of any sudden, continuous and unusual abdominal pain, contrasting with normal physical examination. Risk factors are often unknown at presentation and no biomarker is currently available. The diagnosis is confirmed by abdominal computed tomography angiography identifying intestinal ischaemic injury, either with vascular occlusion or in a context of low flow. Recent knowledge in the pathophysiology of acute mesenteric ischaemia, clinical experience and existing recommendations have generated a multimodal and multidisciplinary management strategy. Based on the gastro-intestinal viability around a simple algorithm, and coordinated by gastroenterologists, the dual aim is to avoid large intestinal resections and death.

How to differentiate spontaneous intramural intestinal hemorrhage from acute mesenteric ischemia

OBJECTS

The purpose of our study was to assess the diagnostic values of laboratory tests to differentiate spontaneous intramural intestinal hemorrhage (SIIH) from acute mesenteric ischemia (AMI) after abdominal computed tomography (CT) survey in the emergency department (ED).

METHOD

We retrospectively included 76 patients diagnosed SIIH or AMI after abdominal CT.

RESULTS

The mean ages of 28 SIIH patients and 48 AMI patients were 75.9 ± 13.7 years and 75.8 ± 11.6 years, respectively. Patients with SIIH had significantly higher rate of Coumadin use (P < .001) and localized tenderness (P < .05). In laboratory findings, SIIH patients had prolonged prothrombin time (PT) (83.6 ± 30.0 vs. 13.4 ± 3.2, P < .001), lower blood urea nitrogen (P < .05), lower creatinine (P < .05), and lower creatine kinase (P < .05). Prolonged PT showed good discriminative value to differentiate acute abdomen patients with SIIH from AMI after abdominal CT, with an area under the receiver operating characteristic curve of 0.980 (95% confidence interval, 0.918-0.998; P < .0001). Prolonged PT cut-off value of ≧22.5 seconds had a sensitivity of 92.9% and a specificity of 100%. Logistic regression analysis identified prolonged PT as an independent predictor of SIIH (odds ratio, OR, 22.2; P = .007).

CONCLUSION

Abdominal pain patients with either SIIH or AMI are rare in the ED, but abdominal CT sometimes cannot help to differentiate them due to similar CT findings. Prolonged PT might help emergency physicians and surgeons differentiate SIIH from AMI in such cases.