Administration of N-acetylcysteine after focal cerebral ischemia protects brain and reduces inflammation in a rat model of experimental stroke

Free radicals and inflammatory mediators are involved in transient focal cerebral ischemia (FCI). Preadministration of N-acetylcysteine (NAC) has been found to attenuate the cerebral ischemia-reperfusion injury in a rat model of experimental stroke. This study was undertaken to investigate the neuroprotective potential of NAC administered after ischemic events in experimental stroke. FCI was induced for 30 min by occluding the middle cerebral artery (MCA). NAC (150 mg/kg) was administered intraperitoneally at the time of reperfusion followed by another dose 6 hr later. Animals were sacrificed after 24 hr of reperfusion. The cerebral infarct consistently involved the cortex and striatum. Infarction was assessed by staining the brain sections with 2,3,5-triphenyltetrazolium chloride. Animals treated with NAC showed a significant reduction in infarct area and infarct volume and an improvement in neurologic scores and glutathione level. Reduction in infarction was significant even when a single dose of NAC was administered at 6 hr of reperfusion. Immunohistochemical and quantitative real-time PCR studies demonstrated a reduction in the expression of proinflammatory cytokines such as tumor necrosis factor alpha (TNFalpha) and interleukin 1beta (IL-1beta) and inducible nitric oxide synthase (iNOS) in NAC compared to that in vehicle-treated animals. The expression of activated macrophage/microglia (ED1) and apoptotic cell death in ischemic brain was also reduced by NAC treatment. These results indicate that in a rat model of experimental stroke, administration of NAC even after ischemia onset protected the brain from free radical injury, apoptosis, and inflammation, with a wide treatment window.     

Abdominal compartment syndrome related to noninvasive ventilation

OBJECTIVE: To study the effects of noninvasive positive pressure ventilation (NIPPV) on intra-abdominal pressure. DESIGN AND SETTING: Single case report from a tertiary teaching hospital. PATIENTS AND METHODS: A 65-year-old man who experienced a sudden respiratory and cardiovascular collapse during NIPPV. This was caused by gastric overdistension due to aerophagia followed by raised intra-abdominal pressure leading to intra-abdominal hypertension and abdominal compartment syndrome. RESULTS: The respiratory and cardiovascular problems resolved immediately after the introduction of a nasogastric tube. This resulted in normalization of IAP. CONCLUSIONS: This is the first case reported of an abdominal compartment syndrome related to NIPPV. Clinicians should be aware of this possible complication while using NIPPV.     

Antibodies to Epstein-Barr virus in patients with chronic fatigue.

To clarify the role of Epstein-Barr virus (EBV) infection and the value of EBV antibody testing in evaluating patients with chronic fatigue, we studied 200 consecutive patients with chronic fatigue (mean duration, 9 years). Complete EBV serologic panels were obtained for 154 patients, 35 (23%) of whom met serologic or clinical criteria for chronic or reactivated EBV infection. We compared these patients with chronic EBV infection (CEBV cases) to 35 age- and sex-matched patients who were selected from the same cohort of fatigued patients but who did not meet the criteria (CEBV control subjects). We found few differences between groups in demographic characteristics, clinical features, and symptoms; CEBV cases were more likely to meet criteria for the proposed chronic fatigue syndrome (14% vs 0%), and to report that they suffered from an influenza-like illness at the onset of their fatigue syndrome (34% vs 12%), that they lost their job because of their fatigue (37% vs 11%), and that their fatigue was improved by recreational activity (26% vs 3%). Physical examination and laboratory testing showed few abnormalities in either group. Psychiatric morbidity was common in both groups, including mood disorders (63% of CEBV cases vs 54% of CEBV controls), anxiety (11% vs 9%) and somatization disorder (9% in each group). We conclude that EBV serologic patterns have little clinical usefulness in evaluating patients with chronic fatigue.     

Results from the International Conference of Experts on Intra-abdominal Hypertension and Abdominal Compartment Syndrome. II. Recommendations

Objective Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) have been increasingly recognized in the critically ill over the past decade. In the absence of consensus definitions and treatment guidelines the diagnosis and management of IAH and ACS remains variable from institution to institution. Design An international consensus group of multidisciplinary critical care specialists convened at the second World Congress on Abdominal Compartment Syndrome to develop practice guidelines for the diagnosis, management, and prevention of IAH and ACS. Methods Prior to the conference the authors developed a blueprint for consensus definitions and treatment guidelines which were refined both during and after the conference. The present article is the second installment of the final report from the 2004 International ACS Consensus Definitions Conference and is endorsed by the World Society of the Abdominal Compartment Syndrome. Results The prevalence and etiological factors for IAH and ACS are reviewed. Evidence-based medicine treatment guidelines are presented to facilitate the diagnosis and management of IAH and ACS. Recommendations to guide future studies are proposed. Conclusions These definitions, guidelines, and recommendations, based upon current best evidence and expert opinion are proposed to assist clinicians in the management of IAH and ACS as well as serve as a reference for future clinical and basic science research.     

Prevalence of intra-abdominal hypertension in critically ill patients: a multicentre epidemiological study

Objective Although intra-abdominal hypertension (IAH) can cause dysfunction of several organs and raise mortality, little information is available on the incidence and risk factors for IAH in critically ill patients. This study assessed the prevalence of IAH and its risk factors in a mixed population of intensive care patients.Design A multicentre, prospective 1-day point-prevalence epidemiological study conducted in 13 ICUs of six countries.Interventions None.Patients Ninety-seven patients admitted for more than 24 h to one of the ICUs during the 1-day study period.Methods Intra-abdominal pressure (IAP) was measured four times (every 6 h) by the bladder pressure method. Data included the demographics, medical or surgical type of admission, SOFA score, etiological factors such as abdominal surgery, haemoperitoneum, abdominal infection, massive fluid resuscitation, and ileus and predisposing conditions such as hypothermia, acidosis, polytransfusion, coagulopathy, sepsis, liver dysfunction, pneumonia and bacteraemia.Results We enrolled 97 patients, mean age 64±15 years, 57 (59%) medical and 40 (41%) surgical admission, SOFA score of 6.5±4.0. Mean IAP was 9.8±4.7 mmHg. The prevalence of IAH (defined as IAP 12 mmHg or more) was 50.5 and 8.2% had abdominal compartment syndrome (defined as IAP 20 mmHg or more). The only risk factor significantly associated with IAH was the body mass index, while massive fluid resuscitation, renal and coagulation impairment were at limit of significance.Conclusion Although we found a quite high prevalence of IAH, no risk factors were reliably associated with IAH; consequently, to get valid information about IAH, IAP needs to be measured.