Mesenteric ischemia

In all forms of mesenteric ischemia, early diagnosis and treatment is imperative. As this disease entity can be evident as a sole clinical event or a secondary event, close observation and suspicion of the diagnosis is advised in those who are at high risk. As the nurse caring for these patients, careful monitoring of the patient's fluid and electrolyte status, nutritional and gastrointestinal status is essential. This, along with assessing for complications and recurrence of ischemia, are the sine qua non of treatment for mesenteric ischemia.     

Mesenteric ischemia: still a deadly puzzle for the medical community

The main goal of this article is to update etiology, epidemiology, diagnosis, treatment and outcome of the various causes of mesenteric ischemia in order to elucidate its labyrinthine clinical riddle, by reviewing the current English medical literature. Mesenteric ischemia is a quite uncommon disorder, observed in the emergency department. It is a life-threatening vascular emergency that requires early diagnosis and intervention to restore mesenteric blood flow and to prevent bowel necrosis and patient death. Consequently, it is a vital diagnosis to make because of its high mortality rate and its thorny complications. The underlying causes vary, and the prognosis depends on the specific findings during clinical examination. Vague and nonspecific clinical findings and limitations of diagnostic studies make the diagnosis a significant challenge. The prognosis of acute mesenteric ischemia of any type is grave. The complications following this medical jigsaw puzzle are also severe. Patients in whom the diagnosis is missed until infarction occurs have a mortality rate of 90%. Even with good treatment, up to 50-80% of patients die. Survivors of extensive bowel resection face lifelong disability. Despite the progress in understanding the pathogenesis of mesenteric ischemia and the development of treatment modalities, the entity remains a diagnostic challenge for clinicians. Delay in diagnosis contributes to a high mortality rate. Early diagnosis and adequate treatment can improve the clinical outcome. Even if diagnostic modalities have improved since the first successful attempts to confront effectively this clinical entity, mesenteric ischemia still remains a lethal diagnostic enigma for the medical community.     

Small bowel enema and diagnosis of chronic nonischemic disturbance of superior mesenteric venous blood flow

Chronic nonischemic disturbance of mesenteric venous blood flow is reported in 11 patients with a mean age of 19 years. This entity, rarely discussed n the literature, is different from acute thrombosis and chronic thrombotic forms with portal hypertension or hypercoagulopathy. In eight patients this syndrome was secondary to organic lesions of different origin: mesenteric vein squeezed by fibrous bands or an abnormal jejunal artery (four cases), lymphoma involving the distal superior mesenteric veins (three cases), hemangioma causing microthrombi (one case). In three patients no etiology or predisposing factor was found. All patients presented with rectal hemorrhage. Small bowel enema showed a constant pattern in 11 patients: small nodules, modified by compression or peristalsis, involving the mesenteric border of the jejunoileal segment, and associated with thick, straight but regular folds. Mesenteric varices were suspected and led to angiographic studies which were normal in three cases, confirmed varices in eight cases, and thrombosis in four cases. Laparotomy was normal in three cases and established the etiological diagnosis in eight cases. Varices were shown in six cases. Arteriography and laparotomy were unable to reach a complete diagnosis.     

ACR appropriateness criteria® imaging of mesenteric ischemia

Mesenteric ischemia is a rare disease associated with high morbidity and mortality. Acute mesenteric ischemia is most commonly secondary to embolism followed by arterial thrombosis, nonocclusive ischemia, and less commonly venous thrombosis. Chronic mesenteric ischemia is almost always caused by atherosclerotic disease, with rare causes including fibromuscular dysplasia and vasculitis. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment. Patients with mesenteric ischemia usually present with nonspecific abdominal symptoms and laboratory findings. This document evaluates and rates the appropriateness of imaging to evaluate patients with clinically suspected mesenteric ischemia. While catheter-based angiography has been considered the reference standard and enables diagnosis and treatment, advances in computed tomography have made it a first-line test in many patients because it is a fast, widely available, and noninvasive study. Abdominal radiographs and ultrasound have a limited role in diagnosing mesenteric ischemia but are commonly the first ordered tests in patients with abdominal pain and may diagnose more common pathologies.     

肠系膜血管栓塞致肠缺血的CT诊断

目的：分析肠系膜血管栓塞致肠缺血的CT表现，提高对本病的CT诊断水平。材料与方法：回顾性分析经临床及病理证实的13例肠系膜血管栓塞的CT平扫及增强表现。结果：10例患者表现出肠系膜血管栓塞直接征象：受累血管内见栓子，其中7例患者CT平扫即表现为系膜血管增粗，管腔密度增高或减低，1例患者因就诊较晚直接表现为系膜血管及门静脉内积气；2例患者CT平扫未见明显系膜血管病变，增强扫描表现为管腔充盈缺损；另3例患CT平扫系膜血管未见异常改变，剖腹探查术后病理证实为系膜血管栓塞。13例患者均表现出肠系膜血栓的间接征象肠缺血：其中11例表现为肠腔扩张积气积液；8例肠壁增厚；5例肠壁变薄；4例肠壁密度增高；2例肠壁积气；4例出现肠系膜水肿；1例系膜内积气；4例肠缺血并发腹膜炎出现腹水。结论：腹部CT检查尤其是增强扫描可直接显示肠系膜血管及其主要分支的管腔情况，对肠系膜血管栓塞致肠缺血具有很高的诊断价值，对不明原因的急性腹痛患者应作为首选检查方法。     

Acute intestinal ischemia due to occlusion of the superior mesenteric artery: detection with Doppler sonography.

The aim of our study was to assess the feasibility of using Doppler sonography for the detection of acute intestinal ischemia due to occlusion of the superior mesenteric artery. Between September 1993 and March 1995, abdominal sonography with Doppler imaging of the mesenteric vessels was performed in 770 patients with emergency admissions for acute abdominal pain. In six cases, the diagnosis, based on surgery or arteriography and computed tomography, was acute intestinal ischemia due to complete or localized occlusion of the superior mesenteric artery. Five cases of occlusion of the superior mesenteric artery were correctly detected by Doppler sonography. These results suggest that Doppler sonography may be a feasible method for detecting acute intestinal ischemia due to proximal superior mesenteric artery occlusion.     

肠系膜血管供血不全12例诊治探讨

目的探讨急性肠系膜血管供血不全的诊断和治疗.方法对1990～2005年经治的12例急性肠系膜血管供血不全病例的临床资料进行回顾性分析.结果本病患者多为高龄,常伴有心血管疾病,易发生绞窄性肠梗阻,死亡率高.结论选用恰当的检查技术、早期诊断、及时手术是提高急性肠系膜血管供血不全治疗效果的关键.     

Conduite à tenir devant une suspicion d’ischémie mésentérique aiguë

Acute mesenteric ischemia (AMI) is a diagnostic and therapeutic emergency medicine. Its mortality remains high (30 to 95%), depending on both its etiologies and the rapidity of treatment. The term acute mesenteric ischemia is currently applied to a wide spectrum of bowel injuries within the distribution of the superior mesenteric vessels, ranging from reversible alterations in bowel function (acute mesenteric ischemia syndrome) to transmural necrosis of the bowel wall (mesenteric infarction). AMI may result from a superior mesenteric embolus, thrombosis of the superior mesenteric artery or vein, or non-occlusive mesenteric ischemia. The lack of specific clinical signs requires other diagnostic means. Abdominal computed tomographic scan is currently the most efficient diagnostic tool. It also helps to rule out diseases that may mimic AMI. Intravenous contrast injection may show mesenteric vascular occlusion and specific abnomalities of the bowel mucosae. Initial treatment consists of volume resuscitation and administration of appropriate doses of vasopressive drugs. The vasospasm treatment needs further clinical research. Diagnostic and therapeutic angiography is not easy to perform in regular practice, whereas a selective superior mesenteric artery catheter may allow a specific treatment for some patients. A multidisciplinary approach is needed for an accurate diagnosis and treatment.     

CT and MR diagnoses of intestinal ischemia

CT and MR imaging have an important role in establishing the diagnosis of mesenteric ischemia. However, without specific signs such as thromboembolism in the mesenteric vessel, intramural or portal venous gas, and the absence of bowel wall enhancement, mesenteric ischemia can be confused with inflammatory or neoplastic gastrointestinal diseases. Arterial or venous occlusion or low-flow state are the main direct causes of mesenteric ischemia. Delayed diagnosis in equivocal cases can be avoided through an understanding of the patholophysiological aspects of mesenteric ischemia as they occur in a variety of other conditions, including: thromboembolism, bowel obstruction, neoplasm, vasculitis, inflammatory diseases, trauma, and drug or radiation therapy.     

Computed tomography in pneumatosis intestinalis: Differential diagnosis and therapeutic consequences

Case reports of five patients with pneumatosis intestinalis diagnosed by computed tomography (CT) are presented. Etiology, differential diagnoses, and clinical consequences arising from CT imaging are discussed. In four of the patients, pneumatosis was found to be secondary to gastric ulcer, colon carcinoma, metastasis in the mesentery, and trauma-induced mesenteric ischemia. In one patient, the etiology remained elusive. Using CT, both the extent and the distribution pattern of pneumatosis could be depicted, allowing for differentiation of primary and secondary forms and assessment of prognosis. Evaluation with a lung window is a prerequisite for reliable diagnosis of pneumatosis with CT. The presence of gas in the mesenteric or portal venous system in mesenteric ischemia is indicative of an unfavorable prognosis.     

Hepatic portal venous gas: clinical significance of computed tomography findings

Hepatic portal venous gas (HPVG) is a rare radiographic finding of significance. Most cases with HPVG are related to mesenteric ischemia that have been associated with extended bowel necrosis and fatal outcome. With the help of computed tomography (CT) in early diagnosis of HPVG, the clinical outcome of patients with mesenteric ischemia has improved. There has been also an increasing rate of detection of HPVG with certain nonischemic conditions. In this report, we present two cases demonstrating HPVG unrelated to mesenteric ischemia. One patient with cholangitis presented abdominal pain with local peritonitis and survived after appropriate antibiotic treatment. Laparotomy was avoided as a result of lack of CT evidence of ischemic bowel disease besides the presence of HPVG. The other case had severe enteritis. Although his CT finding preluded ischemic bowel disease, conservative treatment was implemented because of the absence of peritoneal signs or clinical toxic symptoms. Therefore, whenever HPVG is detected on CT, urgent exploratory laparotomy is only mandatory in a patient with whom intestinal ischemia or infarction is suspected on the basis of radiologic and clinical findings. On the other hand, unnecessary exploratory laparotomy should be avoided in nonischemic conditions that are usually associated with a better clinical outcome if appropriate therapy is prompted for the underlying diseases. Patients with radiographic diagnosis of HPVG should receive a detailed history review and physical examination. The patient's underlying condition should be determined to provide a solid ground for exploratory laparotomy. A flow chart is presented for facilitating the management of patients with HPVG in the ED.     

Nonocclusive mesenteric ischemia: a lethal complication in peritoneal dialysis patients.

Nonocclusive mesenteric ischemia (NOMI) is a relatively uncommon disorder, seen primarily in elderly patients with cardiac disease, and is characterized by progressive intestinal ischemia leading to infarction, sepsis, and death. It is suspected of being the underlying cause in at least 20% - 30% of acute mesenteric ischemia patients. End-stage renal disease patients are among the highest risk populations for developing this lethal complication; however, NOMI is not unique to hemodialysis and can occur in peritoneal dialysis patients as well. Unfortunately, the presentation of NOMI is very similar to that of peritonitis. The key to correct diagnosis is a high index of suspicion in predisposed patients. The high mortality rate is a clear reflection of failure to recognize the syndrome at an earlier, treatable stage. We present our case experience and an extensive review of the literature regarding this dreadful complication that may be reversible if considered early as a possible etiology and the appropriate diagnostic maneuvers undertaken.     

Ischemic enteritis

Ischemic enteritis is a rare disease, but its mortality is high, whether it is caused by anatomic occlusion of the mesenteric macrovasculature or pathophysiologic vasospasm at the microvascular level. Despite advances in the management of the critical ill patient, a large proportion of the patients recognized with this diagnosis succumb acutely to their condition. Lesser degrees of mesenteric ischemia (particularly, in small intestine), even when not manifest overtly as the classic clinical syndrome, may contribute to the development of systemic sepsis and the multiple organ failure syndrome, which leads to death. Therefore, the understanding, recognition, and proper management of mesenteric vascular insufficiency has become very important.     

急性肠系膜血管缺血性疾病的早期诊治探讨

目的探讨急性肠系膜血管缺血性疾病的早期诊断和治疗方法。方法 回顾性总结１９６５～１９９９年急性肠系膜血管缺血性疾病的３９例临床资料。分析其诊断和治疗方法。结果 器质性心脏病、动脉硬化、血栓等病史伴有与腹部体征不相符的剧烈腹痛，应首先考虑肠系膜血管缺血。结论 选择性动脉造影和给药是早期诊断、治疗最有价值的方法。血Ｄ－Ｄｉｍｅｒ是实验室检查血栓形成的敏感指标。及早应用抗凝、溶栓和罂粟硷等药物是避免手术治疗和预防术后复发的有效方法。     

Chronic mesenteric ischemia: stenting of mesenteric arteries

This article focuses on stent placement in mesenteric arteries in patients with the rare diagnosis of chronic mesenteric ischemia. We present a survey from the initial stage of recognition of this gastrointestinal disorder and its manifestations to treatment by stenting to avoid further ischemic episodes and bowel infarction and necrosis. The advantages of stent placement in splanchnic arteries are discussed in comparison to open surgical revascularization.     

双源CT血管成像诊断急性肠系膜缺血价值

目的探讨双源CT血管成像（dual—sourceCTangiography,DSCTA）在急性肠系膜缺血（acutemesentericischemia,AMI）诊断中的价值。方法回顾性分析14例经手术或介入治疗证实AMI患者的DSCTA影像资料。结果14例患者中肠系膜上动脉栓塞2例,肠系膜上动脉血栓形成6例,肠系膜上静脉血栓形成3例（1例合并门静脉血栓）,肠系膜上动脉重度狭窄1例,表现为血管突然中断,管腔内充盈缺损,管壁增厚,管腔变小,钙化影;肠系膜上动脉夹层2例,显示为真假双腔,内膜片清晰。间接征象为不同程度肠腔扩张,肠管内气液平,肠壁增厚或变薄,腹腔积液。增强扫描时肠壁不强化或强化延迟、减弱。结论DSCTA可准确显示AMI直接征象,是较理想的影像学检查方法。     

Acute mesenteric ischemia and malpractice claims

BACKGROUND: Acute mesenteric ischemia can be a difficult diagnosis to make, but delay contributes directly to infarction, and this may provide a setting for malpractice claims. METHODS: We reviewed 180 consecutive malpractice claims submitted by attorneys for medical expert (ME) review during the 12 years ending in late 1998. Seven cases involved acute mesenteric ischemia. RESULTS: Alleged failure to make a timely diagnosis was the basis for 5 of these claims, failure to provide anticoagulant protection for 1, and failure to prevent nonocclusive ischemic infarction for 1. Six claims were closed after ME review and 1 claim involving late diagnosis was settled before trial. CONCLUSIONS: The risk of a malpractice claim is reduced by consideration of computed tomography (CT), angiography, and surgical consultation as soon as a patient is seen whose differential diagnosis includes acute mesenteric ischemia.     

Evaluation of acute mesenteric ischemia: accuracy of biphasic mesenteric multi-detector CT angiography

The purpose of this study was to explore the accuracy of multi-detector row helical CT (MDCT), using a biphasic mesenteric angiography protocol for evaluation of acute mesenteric ischemia (AMI). In total, 79 consecutive patients with clinical signs of AMI underwent contrast enhanced 16- or 40-channel MDCT. MDCT findings were correlated with surgery, endoscopy and clinical outcome. Sensitivity, specificity, and positive and negative predictive values were calculated using the patients in which AMI had been excluded as a control group. In 28 patients the final diagnosis was AMI. In 27 patients (96.4%) MDCT correctly diagnosed AMI (specificity of 97.9%). A sensitivity of 93%, specificity of 100%, and positive and negative predictive values of 100% and 94%, respectively were achieved for the CT findings of visceral artery occlusion, intestinal pneumatosis, portomesenteric venous gas or bowel wall thickening in combination with either portomesenteric thrombosis or solid organ infarction. Our findings suggest that mesenteric MDCT angiography is an accurate tool for fast diagnostic work-up of patients with suspected AMI.     

Contrast‐enhanced sonography in the diagnosis of acute mesenteric ischemia: Case report

Acute mesenteric ischemia is a serious condition associated with high mortality. Multislice CT and magnetic resonance angiography have proved accurate in diagnosing this pathology, which requires a prompt diagnosis to start appropriate therapy. We report the case of an 87‐year‐old woman with acute mesenteric ischemia, in whom contrast‐enhanced sonography visualized the occluded superior mesenteric artery and the infarcted portion of the intestine. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2010     

Computed tomography of superior mesenteric vein thrombosis following appendectomy

During a 5-year period, superior mesenteric vein (SMV) thrombosis was detected with computed tomography (CT) in six patients shortly after an appendectomy. No sign of SMV was present at appendectomy, and a period of more than 2 weeks free of clinical symptoms had elapsed between the appendectomy and the onset of the SMV thrombosis. In four cases, the appendicitis was complicated. These patients had nonspecific signs and symptoms, although two of them had elevation of blood hepatic enzyme levels. In all cases, postcontrast CT demonstrated enlargement of the SMV, with well-defined enhancement of the vascular wall and an intraluminal clot. In one case, CT showed extension of the thrombus to the portal vein with the presence of low-attenuation areas in the liver, consistent with hepatic infarcts. Two patients had predisposing diseases: idiopathic hypersplenism in one case and chronic hepatic disease in the other. SMV thrombosis is a possible complication of appendicitis, and early appendectomy in appendicitis can prevent this complication. Moreover, as in any abdominal surgery, early appendectomy may be complicated by thrombosis of the SMV, thus creating problems of postoperative diagnosis. The complication is more frequent when the initial operation is performed under difficult conditions (peritonitis), or when the patient presents with a coagulopathy. CT is useful in the diagnosis of SMV thrombosis, thus leading to early management with anticoagulant therapy, with a view to avoiding complications such as intestinal ischemia, portal vein thrombosis, and hepatic infarction. Received: 19 March 1997/Accepted after revision: 15 July 1997