D-dimer in the early diagnosis of acute mesenteric ischemia secondary to arterial occlusion in rats

BACKGROUND: Early diagnosis of mesenteric ischemia can be life saving. The aim of this study is to investigate the time-dependent diagnostic value of plasma D-dimer and other ancillary laboratory evaluations such as creatine phosphokinase, lactic dehydrogenase, aspartate aminotransferase, alanine aminotransferase, amylase, and leukocyte count in an experimental superior mesenteric arterial occlusion (SMA-O) model in rats. METHODS: Forty male Wistar-Albino rats were separated into 4 groups: 2-, 4-, 6-, and 12-hour SMA-O groups. After laparotomy, the SMA was identified and ligated for 2, 4, 6 and 12 h in the 4 respective study groups. Blood samples were taken for laboratory tests 2 h after laparotomy in the control group and at the end of the ischemic period in the study groups. RESULTS: The longer the duration of mesenteric ischemia, the higher were the serum D-dimer levels in the study groups, and statistical significance was obtained at 2 h (p = 0.021). Sensitivity, positive predictive value, negative predictive value, and accuracy of the relation were 88.8, 88.8, 100 and 90%, respectively. Leukocyte count was significantly higher than controls after 12 h. No other laboratory parameter correlated positively with the duration of mesenteric ischemia. CONCLUSION: Serum D-dimer measurements may be a valuable diagnostic parameter in the early diagnosis of mesenteric ischemia.     

The use of intraperitoneal xenon for early diagnosis of acute mesenteric ischemia

We evaluated the technique of intraperitoneal use of xenon Xe 133, previously described for the diagnosis of early intestinal strangulation obstruction in rats and dogs, for the recognition of acute mesenteric vascular occlusion in these animals. 133Xe was injected intraperitoneally into five groups of six rats: control, sham operation, superior mesenteric artery (SMA) ligation, superior mesenteric vein ligation, and portal vein ligation. Residual gamma-activity was monitored by external counting and camera imaging. At 30 minutes after injection, the activity was significantly higher in the rats from the three groups with vascular ligation than in the control and sham operation animals (P less than 0.001). gamma-Camera images reflected these findings, with positive images only in the rats that underwent vascular ligation. "Blinded" readings of the 30 sets of scans confirmed the diagnostic accuracy of the images. Results were essentially the same in a second series of experiments in eight control dogs and six dogs with balloon occlusion of the SMA. Concentrations of isotope in ischemic intestine ranged from 10(3) to 10(5) times the levels in adjacent normal bowel. These levels and the positive images appeared early, prior to the development of tissue necrosis. The intraperitoneal use of 133Xe therefore continues to show promise for the recognition of patients with early intestinal ischemia.     

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目的 探讨急性肠系膜血管供血不全的诊断和治疗。方法 对1972年11月至1999年10月经治的20例急性肠系膜血管供血不全的临床资料进行回顾性分析。结果 该病多为高龄，常伴有心血管疾病和发生绞窄性肠梗阻，病死率很高（本组为45%）。结论 充分认识该病，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。     

CT灌注成像早期诊断犬急性脑梗死的实验研究

目的探讨CT灌注成像技术(CTP)对脑梗死超急性期诊断的应用价值。方法成年比格犬10只,介入技术建立犬急性脑栓塞动物模型,分别在栓塞前及栓塞后2 h行脑血管造影,观察所栓塞血管的血流情况,同时在栓塞后2 h行CT平扫及CTP检查。24 h处死动物后取脑组织进行病理检查。结果10只犬全部成功栓塞左侧大脑中动脉,其中4只合并其他脑血管栓塞,至栓塞后2 h造影所有被栓血管没有发生再通。CT平扫没有发现明确异常,CTP检查显示9只局部脑血流量减少为对侧的33.7%~69.2%(平均0.483±0.132),1只无明显的变化,与数字减影血管造影诊断比较没有明显的统计学差异(P>0.05)。24 h后动物均存活,没有出现严重并发症,病理检查证实在深部脑组织皆出现脑梗死病灶。结论CTP检查可快速、准确、无创地评价犬急性局部脑梗死动物模型的脑血流动力学变化。     

Early diagnosis of acute mesenteric ischemia after cardiopulmonary bypass

BACKGROUND: The aim of this study is to identify significant risk factors and eventual clinical markers associated with acute mesenteric ischemia (AMI) after cardiopulmonary bypass. METHODS: The study was retrospectively performed on a group of 19 patients (group A) undergoing cardiac surgery between January 1991 and December 1999, who developed AMI within 30 days of their hospitalization. A control group of 48 patients (group B) was compared in order to define preoperative and operative risk factors for AMI. RESULTS: At the abdominal operation, a non-occlusive mesenteric ischemia was found in every case. In-hospital mortality was 84.2% (16/19). Compared to the control, there was a significant difference in aortic cross-clamp time (p<0.001) and use of inotropic drugs (p<0.01). Postoperatively, the studied group (group A) had a significantly higher mean value of the enzymatic serum levels at any time. CONCLUSIONS: A high index of suspicion for mesenteric ischemia after cardiopulmonary bypass should be considered in patients with conditions of hypoperfusion. The early laboratory signs of AMI might be searched during the first postoperative hours.     

Effects of glucagon and prostacyclin in acute occlusive and postocclusive canine mesenteric ischemia

Effects of glucagon and prostacyclin (PGI2) were studied in anesthetized dogs during sequential occlusive and postocclusive mesenteric ischemia induced by 90 min of tourniquet stenosis of the superior mesenteric artery (SMA). After 30 min of SMA stenosis, glucagon (1 microgram/kg/min, n = 7), PGI2 (30 ng/kg/min, n = 7), or saline (1 ml/min, n = 3) was infused intravenously for 30 min, followed by 30 min of continued ischemia. SMA flow and distal SMA pressure ( SMAP ) decreased 76% with SMA stenosis (P less than 0.01). Ileal wall flow measured by radiolabeled microspheres decreased from 45 to 13 ml/min/100 g (P less than 0.01); mesenteric AV O2 difference ( AVDO2 ) increased from 5.1 to 10.1 ml/dl (P less than 0.01); and mesenteric O2 consumption (VO2) decreased by 48% (P less than 0.05). Glucagon infusion caused a further decrease in ileal wall flow, to 10 ml/min/100 g (P less than 0.05), and an increase in AVDO2 to 11 ml/dl (P less than 0.05), despite a 22% increase in cardiac output. PGI2 caused a similar decrease in ileal wall flow and an increase in AVDO2 , although these were not statistically significant. Saline infusion caused no change in measured variables. In the second phase of this study, SMA blood flow was restored by tourniquet release. After animals had stabilized for 30 min, a repeat 30-min drug infusion was studied. In this postocclusive period, persistent gut ischemia was indicated by a reduction in VO2 to 76% of original baseline, associated with a 50% decrease in both CO and SMAQ . Intravenous infusion of glucagon at this time increased SMAQ by 195% (P less than 0.05) and resulted in a return of VO2 to its original baseline level. PGI2 infusion caused a 21% increase in SMAQ and a 16% decrease in AVDO2 (NS), but had no significant effect on VO2. Glucagon was effective in the management of postocclusive mesenteric ischemia but appeared to have a detrimental effect on ileal blood flow in severe occlusive ischemia.     

急性肠系膜血管缺血性疾病的早期诊断和治疗(附14例报告)

目的　探讨急性肠系膜缺血性疾病的早期诊断和治疗方法。方法　分析 1987年 1月- 2 0 0 1年 12月急性肠系膜缺血性疾病 14例临床资料。结果　急性肠系膜上动脉栓塞 6例 ,急性肠系膜上动脉血栓形成 3例 ,急性肠系膜上静脉血栓形成 4例 ,非血管阻塞性急性肠缺血 1例 ,均经病理证实。 10例有与腹部体征不相符的剧烈腹痛 ,6例存在慢性肠缺血表现。选择性肠系膜动脉造影确诊 1例 ,CT确诊 2例 ,11例为术中发现。 14例均行手术治疗 ,术后均行溶栓、抗凝治疗 ,9例治愈 ,5例死亡。结论　①器质性心脏病、动脉硬化、血栓等病史伴与腹部不相符的剧烈腹痛是急性肠系膜缺血性疾病的重要临床特征 ;②选择性动脉造影和CT是最有价值的诊断方法 ;③血管的再管化、必要的肠切除和术前、后抗凝及溶栓是提高疗效的重要保证 ;④出现慢性肠缺血表现时 ,预防性抗凝可能是降低死亡率的有效方法     

Nonocclusive acute mesenteric ischemia

The authors present one case of acute mesenteric ischemia appeared to the patient 70 years old, with HTA and coronary heart disease with heart arrhythmia treated with angiotensin-converting-enzyme inhibitor, anti arrhythmia agents and antithrombin therapy (trombostop). Acute mesenteric ischemia is not an isolated clinical entity, but a complex of diseases, including acute mesenteric arterial embolus and thrombus, mesenteric venous thrombus and nonocclusive mesenteric ischemia. These diseases have common clinical features caused by impaired blood perfusion of the intestine, bacterial translocation and systemic inflammatory response syndrome. Reperfusion injury is another important feature of nonocclusive mesenteric ischemia. We discuss about the nonocclusive mesenteric ischemia is the most lethal form of acute mesenteric ischemia because of the poor understanding of its pathophysiology and its nonspecific symptoms, which often delay its diagnosis. Although acute mesenteric ischemia is still lethal and in-hospital mortality rates have remained high over the last few decades, accumulated knowledge on this condition is expected to improve its prognosis.     

Aggressive approach to acute mesenteric ischemia.

An aggressive diagnostic and therapeutic approach to acute mesenteric ischemia can dramatically lower the mortality of this lethal disease. The cornerstones of this approach are the earlier and more liberal use of angiography and the use of intra-arterial infusions of vasodilators in the treatment of both nonocclusive and occlusive mesenteric ischemia.     

Management of acute mesenteric ischemia

Acute mesenteric ischemia is a serious illness requiring prompt surgical attention. The clinical presentation, diagnostic strategy, and management of this disease are reviewed. Options for revascularization are briefly outlined.     

Perioperative diagnosis of mesenteric ischemia in acute aortic dissection by transesophageal echocardiography

Objective: Although computed tomography, angiography, or magnetic resonance imaging is most commonly used for diagnosing mesenteric ischemia caused by acute aortic dissection, use of these modalities is often limited in the perioperative period. Thus, we have introduced transesophageal echocardiography to cover this deficit. Purpose of this study is to report the feasibility and accuracy of transesophageal echocardiographic diagnosis on mesenteric ischemia. Methods: The consecutive 24 cases with acute aortic dissection which involved abdominal aorta and underwent surgery were examined. The celiac artery and superior mesenteric artery was visualized with 5 MHz biplane transesophageal echocardiography and was assessed for presence of dissection and blood flow in each of true and false lumen. The transesophageal echocardiographic findings were then correlated to the clinical course, computed tomographic findings, and laboratory data. Results: The celiac artery and superior mesenteric artery was successfully visualized in 24 cases (100%) and 23 cases (95.8%), respectively. Perfusion patterns in superior mesenteric artery were categorized into four patterns: (1) intact artery with adequate perfusion (type A: 14 cases); (2) dissection in the artery but with adequate perfusion in true lumen (type B: 5 cases); (3) dissection in the artery with narrowed true lumen compressed by false lumen without detectable blood flow (type C: 1 case); and (4) obstruction of arterial orifice by the intimal flap with narrowed true lumen in the proximal aorta (type D: 2 cases). One case with immediate postoperative death and another case with unsuccessful visualization of superior mesenteric artery were excluded from the analysis. Clinically apparent intestinal ischemia was present in three cases: one case with type C and two cases with type D, but in none of the remaining 19 cases with type A or type B (both sensitivity and specificity were 100%). The superior mesenteric artery was opacified in all of these three cases with ischemia. Conclusions: The transesophageal echocardiographic assessment is feasible in nearly all patients and potentially provides correct diagnosis on intestinal ischemia in the perioperative period of acute aortic dissection. Types C and D indicate significant mesenteric malperfusion.     

血清酶谱检查在家兔急性肠系膜缺血性疾病诊断中的作用

目的研究急性肠系膜缺血后各时段酶谱变化规律,为临床早期诊治该病提供帮助。方法将36只家兔分为动脉阻断、静脉阻断、动静脉阻断3组,每组12只。每组动物分别于阻断前、阻断后1、3、6、9h抽静脉血,检验血清内丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、碱性磷酸酶(ALP)、谷酰转酞酶(γ-GT)、肌酸激酶(CK)、肌酸激酶同工酶(CK—MB)、乳酸脱氢酶(LDH)水平。同时观察肠管的颜色变化。结果各组家兔肠管在血管被阻断3h后开始发生坏死,同时ALT、AST、ALP、γ-GT、LDH均有明显升高。结论血清酶谱检查有助急性肠系膜缺血性疾病的诊断。     

Early diagnosis in acute mesenteric ischemia. Case series and clinical review

The AA report on 12 cases of intestinal infarction for acute mesenteric ischemia (IMA) in critical patients observed in the last 2 years. In this work some clinical data, blood tests and strumental considerations are described. IMA is a vascular emergency with severe prognosis and high rate morbidity and mortality, often correlated to a diagnostic delay. The discrepancy between symptoms and clinical objectivity must suggest the suspect, especially in patients with cardiac pathology, short lasting diarrhoea, bowel hemorrhage or only abdominal pain rebel to the analgesics; with the laboratory indexes and strumental data it can be carried out an early diagnosis and then begin the more opportune therapeutical treatment. The increase of blood sugar together to the triad leucocytosis--haemoconcentration and metabolic acidosis, in previously non diabetic patients, confirm the suspect of IMA in the very initial phases of this pathology.     

腹腔镜早期诊治急性肠系膜静脉血栓的价值

目的 :探讨腹腔镜对急性肠系膜静脉血栓 (MVT)的早期诊治价值。方法 :分析在诊断性腹腔镜检查中获得早期诊治MVT 5例的临床资料 ,判断价值。结果 :5例MVT全部确诊并获得及时治疗。结论 :诊断性腹腔镜检查可以提高MVT早期确诊率 ,避免和减少肠管的坏死和切除     

Serum phosphate levels in acute bowel ischemia. An aid to early diagnosis

Serum phosphate levels were studied in 18 patients with acute intestinal infarction as proved by laparotomy. Serum phosphate was increased preoperatively (6.12 +/- 0.75 mg/dl) in 94.4 per cent of cases. False-positive results were not recorded. The rise in phosphate was observed 4-12 hr (6.82 +/- 2.65) after the beginning of symptoms and was significantly higher when compared with both normal limits (3-5 mg/dl) and phosphate levels of 24 patients with acute abdominal conditions not associated with intestinal ischemia. This study suggests that determination of serum phosphate should be used as screening method for early detection and treatment of patients with acute intestinal ischemia.     

Neutrophil-to-lymphocyte ratio as a diagnostic biomarker for the diagnosis of acute mesenteric ischemia

Purpose

Due to the diagnostic challenges and dreadful consequences of delayed treatment of acute mesenteric ischemia (AMI), a variety of diagnostic markers have been previously studied. However, the diagnostic value of neutrophil-to-lymphocyte ratio (NLR), which has been suggested to be a predictor of inflammation, has never been studied for AMI.

Methods

The data of 70 patients who underwent laparotomy (n = 8) and/or bowel resection (n = 62) for AMI (n = 70) between January 2009 and March 2014 were retrospectively analyzed. To investigate the studied parameters’ role in the differential diagnosis of AMI, control groups were selected from most common reasons of inflammation-related emergent surgery, acute appendicitis (AA, n = 62) and normal appendix (NA, n = 61). White blood cell (WBC), red cell distribution width (RDW), NLR and mean platelet volume (MPV) values were recorded. Outcome variables of the study were defined as diagnostic and prognostic role of NLR in AMI.

Results

RDW and NLR values were found to be higher in the AMI group than the AA group (p < 0.001 and p < 0.001). Also, WBC and MPV values were higher in the AMI group than the NA group (p = 0.001 and p < 0.001). Combined sensitivity, specificity, positive predictive value and negative predictive value of RDW and NLR for recommended cut-off values were 69.4, 71.2, 57.8 and 80.4 %, respectively.

Conclusion

High NLR value (>9.9) seems to be a valuable diagnostic marker of acute mesenteric ischemia. Combined use of NLR, RDW and other clinical assessment, could help the diagnosis of AMI, especially in the absence of advanced imaging modalities and expert radiologic interpretation.