Diagnostic value of arterial blood gas lactate concentration in the different forms of mesenteric ischemia.

PURPOSE: The role of serum lactate measurement in patients with intestinal ischemia still remains unclear. The aim of this study was to prospectively evaluate the diagnostic performance of arterial blood gas lactate concentrations in the patients with acute mesenteric ischemia and its different forms. METHODS: All the patients reporting abdominal pain associated with risk factors for mesenteric ischemia underwent arterial blood gas and contrast enhanced abdominal computer tomography (CT). RESULTS: At CT, 201 patients (70.7%) showed a nonischemic disease (group 1) and 83 patients (29.2%) showed findings of mesenteric ischemia. Out of these, 35 patients (42.1%) showed bowel ischemia secondary to non vascular causes (group 2) and 48 (57.8%) had a vascular intestinal ischemia (group 3). Out of these, 20 showed small bowel arterial occlusion (group 3a), 13 a small bowel nonocclusive ischemia (group 3b), 7 a venous small bowel occlusion (group 3c) and 8 showed isolated colonic ischemia (group 3d). The median lactate serum level was significantly higher in patients with vascular ischemia if compared with patients with nonischemic disease and secondary mesenteric ischemia (p < 0.0001; Kruskal-Wallis test). The areas under ROC curves for the lactate serum levels in the groups 2, 3, 3a, 3b, 3c and 3d were, respectively, 0.61, 0.85, 0.93, 0.93, 0.68 and 0.67. CONCLUSIONS: Arterial blood gas lactate levels seem to show good diagnostic accuracy in diagnosing small bowel arterial and nonocclusive ischemia and poor accuracy in diagnosing secondary mesenteric ischemia, small bowel venous ischemia and ischemic colitis.

Non operative management of blunt splenic trauma: a prospective evaluation of a standardized treatment protocol.

PURPOSE: The advantages of the conservative approach for major spleen injuries are still debated. This study was designed to evaluate the safety and effectiveness of NOM in the treatment of minor (grade I-II according with the American Association for the Surgery of Trauma; AAST) and severe (AAST grade III-V) blunt splenic trauma, following a standardized treatment protocol. METHODS: All the hemodynamically stable patients with computer tomography (CT) diagnosis of blunt splenic trauma underwent NOM, which included strict clinical and laboratory observation, 48-72 h contrast-enhanced ultrasonography (CEUS) follow-up and splenic angioembolization, performed both in patients with admission CT evidence of vascular injuries and in patients with falling hematocrit during observation. RESULTS: 87 patients [32 (36.7 %) women and 55 (63.2 %) men, median age 34 (range 14-68)] were included. Of these, 28 patients (32.1 %) had grade I, 22 patients (25.2 %) grade II, 20 patients (22.9 %) grade III, 11 patients (12.6 %) grade IV and 6 patients (6.8 %) grade V injuries. The overall success rate of NOM was 95.4 % (82/87). There was no significant difference in the success rate between the patients with different splenic injuries grade. Of 24 patients that had undergone angioembolization, 22 (91.6 %) showed high splenic injury grade. The success rate of embolization was 91.6 % (22/24). No major complications were observed. The minor complications (2 pleural effusions, 1 pancreatic fistula and 2 splenic abscesses) were successfully treated by EAUS or CT guided drainage. CONCLUSIONS: The non operative management of blunt splenic trauma, according to our protocol, represents a safe and effective treatment for both minor and severe injuries, achieving an overall success rate of 95 %. The angiographic study could be indicated both in patients with CT evidence of vascular injuries and in patients with high-grade splenic injuries, regardless of CT findings.

7T mMR in the assessment of acute arterial mesenteric ischemia in a rat model.

To validate a rat model of acute arterial mesenteric ischemia correlating MRI patterns with macro and microscopic changes in the small bowel. Thirty Sprague-Dawley rats were assigned to two experimental groups (Group I and Group II) of fifteen rats each. Group I underwent surgical procedure of superior mesenteric artery (SMA) ligation, followed by macroscopic observation. In Group II, a loop was tied loosely around the SMA without occluding the vessel. Three days after surgery, the loop was tied by external tips to completely occlude the artery. 7T microMR (7Tesla microMR) was performed before and 8 hours after SMA occlusion. At predetermined time-points the histopathological examinations were performed in both of groups. Macroscopic monitoring revealed thinning of mesenteric vessels, hypotonic reflex ileus and chromatic change of some loops. 7T microMR sequences evidenced loop dilation with gas-fluid mixed stasis, intraperitoneal free fluid and bowel wall hyperintensity. There were no significant differences in the histological analysis between the two groups. The gap of three days from surgery, adopted in the Group 2, allowed to avoid signs of peritoneal and mesenteric irritation which could bias imaging patterns. MR succeeded to identify the signs of arterial mesenteric ischemia.

Gastrointestinal perforation: ultrasonographic diagnosis.

Gastrointestinal tract perforations can occur for various causes such as peptic ulcer, inflammatory disease, blunt or penetrating trauma, iatrogenic factors, foreign body or a neoplasm that require an early recognition and, often, a surgical treatment.Ultrasonography could be useful as an initial diagnostic test to determine, in various cases the presence and, sometimes, the cause of the pneumoperitoneum.The main sonographic sign of perforation is free intraperitoneal air, resulting in an increased echogenicity of a peritoneal stripe associated with multiple reflection artifacts and characteristic comet-tail appearance.It is best detected using linear probes in the right upper quadrant between the anterior abdominal wall, in the prehepatic space.Direct sign of perforation may be detectable, particularly if they are associated with other sonographic abnormalities, called indirect signs, like thickened bowel loop and air bubbles in ascitic fluid or in a localized fluid collection, bowel or gallbladder thickened wall associated with decreased bowel motility or ileus.Neverthless, this exam has its own pitfalls. It is strongly operator-dependant; some machines have low-quality images that may not able to detect intraperitoneal free air; furthermore, some patients may be less cooperative to allow for scanning of different regions; sonography is also difficult in obese patients and with those having subcutaneous emphysema. Although CT has more accuracy in the detection of the site of perforation, ultrasound may be particularly useful also in patient groups where radiation burden should be limited notably children and pregnant women.

Intestinal Ischemia: US-CT findings correlations.

BACKGROUND: Intestinal ischemia is an abdominal emergency that accounts for approximately 2% of gastrointestinal illnesses. It represents a complex of diseases caused by impaired blood perfusion to the small and/or large bowel including acute arterial mesenteric ischemia (AAMI), acute venous mesenteric ischemia (AVMI), non occlusive mesenteric ischemia (NOMI), ischemia/reperfusion injury (I/R), ischemic colitis (IC). In this study different study methods (US, CT) will be correlated in the detection of mesenteric ischemia imaging findings due to various etiologies. METHODS: Basing on experience of our institutions, over 200 cases of mesenteric ischemia/infarction investigated with both US and CT were evaluated considering, in particular, the following findings: presence/absence of arterial/venous obstruction, bowel wall thickness and enhancement, presence/absence of spastic reflex ileus, hypotonic reflex ileus or paralitic ileus, mural and/or portal/mesenteric pneumatosis, abdominal free fluid, parenchymal ischemia/infarction (liver, kidney, spleen). RESULTS: To make an early diagnosis useful to ensure a correct therapeutic approach, it is very important to differentiate between occlusive (arterial,venous) and nonocclusive causes (NOMI). The typical findings of each forms of mesenteric ischemia are explained in the text. CONCLUSION: At present, the reference diagnostic modality for intestinal ischaemia is contrast-enhanced CT. However, there are some disadvantages associated with these techniques, such as radiation exposure, potential nephrotoxicity and the risk of an allergic reaction to the contrast agents. Thus, not all patients with suspected bowel ischaemia can be subjected to these examinations. Despite its limitations, US could constitutes a good imaging method as first examination in acute settings of suspected mesenteric ischemia.

Primary cutaneous cryptococcosis.

Cryptococcal infections in immuno-compromised patients are of major importance. Current opinion holds that cutaneous cryptococcal infections in these patients indicate disseminated disease. In our renal transplant patient with primary cutaneous cryptococcosis, intravenously administered antifungal chemotherapy resulted in resolution of the disease and appears to have prevented disseminated infection.