The value of D-dimer and platelet-lymphocyte ratio combined with CT signs for predicting intestinal ischemia in patients with bowel obstruction.

OBJECTIVE: To investigate the diagnostic value of D-dimer, platelet-lymphocyte rate (PLR) and CT signs for intestinal ischemia in patients with bowel obstruction. METHODS: We retrospectively analyzed the clinical and imaging data of 105 patients diagnosed with bowel obstruction, and performed univariate and multivariate analyses to determine the independent risk factors for intestinal ischemia in patients with bowel obstruction. Moreover, the receiver operating characteristic curve (ROC) was plotted to examine the diagnostic value of D-dimer, PLR and CT signs in patients with bowel obstruction. Besides, Kappa tests were used to assess inter-observer agreement. RESULTS: We included 56 men (53%) and 49 women (47%) with mean age of 66.05 ± 16 years. Univariate and multivariate analyses showed that D-dimer, PLR and two significant CT signs (i.e., increased unenhanced bowel-wall attenuation and mesenteric haziness) were independent risk factors for intestinal ischemia in patients with bowel obstruction. ROC analysis showed that the combined use of D-dimer, PLR and the said two CT signs had better performance than single indicators in predicting intestinal ischemia in patients with bowel obstruction. The area under the curve (AUC) of the joint model III was 0.925 [95%CI: 0.876-0.975], with a sensitivity of 79.2% [95CI%: 67.2-91.1] and a specificity of 91.2% [95%CI: 83.7-98.9]. CONCLUSION: The combined use of D-dimer, PLR and CT signs has high diagnostic value for intestinal ischemia in patients with bowel obstruction and will prompt surgical exploration to evaluate intestinal blood flow.

Ischemia-modified albumin in rheumatic diseases: A systematic review and meta-analysis.

INTRODUCTION: The identification of novel, easily measurable disease biomarkers might enhance the diagnosis and management of patients with rheumatic diseases (RDs). We conducted a systematic review and meta-analysis of ischemia-modified albumin (IMA), a marker of oxidative stress, acidosis, and ischemia, in RD patients and healthy controls. METHODS: We searched PubMed, Web of Science, and Scopus from inception to January 15, 2024. The risk of bias and the certainty of evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist and GRADE, respectively. RESULTS: In 20 studies investigating a total of 1188 RD patients (mean age 45 years, 64% females) and 981 healthy controls (mean age 44 years, 66% females), RD patients had significantly higher IMA concentrations when compared to controls (standard mean difference, SMD = 0.50, 95% CI: 0.18-0.83, p = .003; I2 = 92.4%, p < .001; low certainty of evidence). In subgroup analysis, the pooled SMD was significantly different in studies investigating ankylosing spondylitis (p < .001), Behçet's disease (p < .001), and rheumatoid arthritis (p = .033), but not familial Mediterranean fever (p = .48). Further associations were observed between the pooled SMD and the broad classification of autoimmune and/or autoinflammatory diseases, the study country, and the method used to measure IMA. CONCLUSION: Our study suggests that IMA is a promising biomarker of oxidative stress, acidosis, and ischemia, as it can effectively discriminate between patients with different types of RDs and healthy controls. Our results warrant confirmation in longitudinal studies of patients with different types of RDs and different ethnicities (PROSPERO registration number: CRD42024509126).

Higher Levels of Cytokines in Patients with Chronic Limb-Threatening Ischemia.

BACKGROUND: Inflammation is a key element in the initiation and progression of peripheral arterial disease (PAD). Understanding the impact of inflammatory molecules, as cytokines in PAD could help us to improve the prognosis of these patients. The main goal of this study was to compare the serum level of cytokines between patients with claudication to those with chronic limb-threatening ischemia (CLTI). The second objective was to evaluate the relationship between the levels of cytokines and death or amputation rate. METHODS: An observational, single-center, and prospective study was conducted from January 2018 to July 2022. The study was approved by the ethical commission of the Local Hospital (75/2017). Patients with PAD, suggested by the clinical history and objective examination and confirmed with ankle-brachial index, attending vascular surgery consultations of the first author were included. The following exclusion criteria were applied: i) bedridden individuals or subjects who refused to participate in the protocol; ii) diseases responsible for body composition changes or proinflammatory state; iii) recent diet change, iv) active malignancy, v) autoimmune disease, vi) active infection, vii) chronic renal failure (glomerular filtration rate <30 mL/min/1.73 m2), or viii) heart failure in the past 3 months. This cohort was observed at admission, 3, 6, and 12 months. A panel of 27 cytokines was determined with ELISA, at baseline. RESULTS: We included 119 subjects (mean age: 67.58 ± 9.60 years old; 79.80% males), 65 patients with claudication and 54 with CLTI. From the 27 cytokines analyzed, patients with CLTI, when compared to those with claudication, had a higher serum level of 11 cytokines: IL1ra, IL-6, IL-8, IL12 p70, G-CSF, IP-10, MCP-1, MIP-1α, PDGF-ß, RANTES, and TNF-α. From the group of patients with CLTI those who underwent a major amputation had a higher serum level of FGF-basic [median = 49.04; interquartile range = 37.03-52.49; versus median = 33.04; interquartile range = 28.60-38.98; P = 0.001]. CONCLUSIONS: Patients with CLTI have higher serum level of inflammatory cytokines, which may have role in the prognosis of these patients.

The Role of Procalcitonin in Predicting Failure of Non-operative Management in Bowel Obstructions.

Procalcitonin has been investigated as a marker for bowel ischemia. This study examined the role of procalcitonin in predicting failure of non-operative management (NOM) in bowel obstructions. Patients with bowel obstructions at a single center from August 2022 to January 2023 were prospectively enrolled (n = 79). Lactic acid (LA) and procalcitonin were collected after surgical consultation. The primary outcome was success or failure of NOM. Univariate analysis, multivariable logistic regression, and performance measures of procalcitonin and LA in predicting bowel ischemia was performed. Of 79 patients included, 48 (61%) required operative intervention during index admission. There were no significant differences in demographics, comorbidities, procalcitonin, nor LA between groups. Time from last bowel movement was associated with failure of NOM (OR 1.03 [95% CI 1.01-1.06]; P = .008), though initial procalcitonin or LA was not. Procalcitonin >.3 ng/mL had acceptable sensitivity in screening for bowel ischemia.

Can Ischemia-Modified Albumin Be a Helpful Marker in the Diagnosis and Follow-Up of Childhood Intussusception?

OBJECTIVES: Intussusception is the invagination of a proximal segment of the intestine into a more distal segment. The present study aimed to determine the sensitivity of the ischemia-modified albumin (IMA) and the correlation between IMA and the severity of intestinal ischemia in intussusception cases. METHODS: Thirty-six consecutive children aged between 0 and 16 years presenting with the clinical and radiological features of intestinal obstruction caused by intussusception were enrolled in the study. The age- and sex-matched control group was composed of patients undergoing outpatient surgery. The patients were categorized as cases of type I (ileoileal), type II (ileocecal), and type III (colocolic) based on the ultrasonography findings. RESULTS: The mean IMA level of the intussusception group was 179.13 ± 220.33 ng/mL, whereas the mean level was found as 89 ± 70.9 ng/mL in the control group. When the patients were categorized as ileoileal, ileocecal, and colocolic, the mean IMA levels were detected as 235.65 ± 268.14 ng/mL, 174.46 ± 212.8 ng/mL, and 46.95 ± 19.56 ng/mL, respectively. There was a moderate correlation between the invaginated segment lengths measured by the surgeon during the operation and IMA levels. CONCLUSIONS: Our study findings reveal that IMA can be used as an auxiliary diagnostic marker in patients presenting with symptoms and signs suggestive of intussusception. Thus, patients can be screened for mechanical bowel obstruction due to intussusception and may be referred to pediatric surgery centers earlier for further examination.

Remnant Cholesterol, Not LDL Cholesterol, Explains Peripheral Artery Disease Risk Conferred by apoB: A Cohort Study.

BACKGROUND: Elevated apoB-containing lipoproteins (=remnants+LDLs [low-density lipoproteins]) are a major risk factor for atherosclerotic cardiovascular disease, including peripheral artery disease (PAD) and myocardial infarction. We tested the hypothesis that remnants and LDL both explain part of the increased risk of PAD conferred by elevated apoB-containing lipoproteins. For comparison, we also studied the risk of chronic limb-threatening ischemia and myocardial infarction. METHODS: apoB, remnant cholesterol, and LDL cholesterol were measured in 93 461 individuals without statin use at baseline from the Copenhagen General Population Study (2003-2015). During up to 15 years of follow-up, 1207 had PAD, 552 had chronic limb-threatening ischemia, and 2022 had myocardial infarction in the Danish National Patient Registry. Remnant and LDL cholesterol were calculated from a standard lipid profile. Remnant and LDL particle counts were additionally measured with nuclear magnetic resonance spectroscopy in 25 347 of the individuals. Results were replicated in 302 167 individuals without statin use from the UK Biobank (2004-2010). RESULTS: In the Copenhagen General Population Study, multivariable adjusted hazard ratios for risk of PAD per 1 mmol/L (39 mg/dL) increment in remnant and LDL cholesterol were 1.9 (95% CI, 1.5-2.4) and 1.1 (95% CI, 1.0-1.2), respectively; corresponding results in the UK Biobank were 1.7 (95% CI, 1.4-2.1) and 0.9 (95% CI, 0.9-1.0), respectively. In the association from elevated apoB to increased risk of PAD, remnant and LDL cholesterol explained 73% (32%-100%) and 8% (0%-46%), respectively; corresponding results were 63% (30%-100%) and 0% (0%-33%) for risk of chronic limb-threatening ischemia and 41% (27%-55%) and 54% (38%-70%) for risk of myocardial infarction; results for remnant and LDL particle counts corroborated these findings. CONCLUSIONS: PAD risk conferred by elevated apoB-containing lipoproteins was explained mainly by elevated remnants, while myocardial infarction risk was explained by both elevated remnants and LDL.

Rivastigmine prevents injury induced by ischemia and reperfusion in rat liver

Abstract Purpose: To evaluate whether pre-treatment with rivastigmine is able to attenuate the I/R induced lesions in rat liver. Methods: SHAM animals or those submitted to I/R, non-treated or pre-treated with rivastigminine (2mg/kg) either 50 or 15 minutes before ischemia, were used. After I/R protocol, these animals were killed and their livers were harvested to measurement of the mitochondrial swelling as well as the malondialdehyde (MDA), nitrite and nitrate tissue concentration. Blood was also harvested for serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) determinations. Results: I/R promoted a significant increase of mitochondrial swelling in the studied animals. This increase of mitochondrial swelling was partially prevented by rivastigmine, but only if administered 50 minutes before ischemia. No significant modification of MDA, nitrite or nitrate tissue concentrations was observed in consequence of I/R, followed or not by rivastigmine treatments. In addition, I/R elevated both AST and ALT. These elevations of serum enzymes were not reversed by the different rivastigmine treatments. Conclusions: Rivastigmine administered 50 minutes before ischemia attenuates I/R-induced mitochondrial swelling, that indicates liver injury. This protective effect may be related to a greater stimulation of α7nAChR present in the Kupffer cells by the non-methabolized ACh, leading to an attenuation of I/R-induced inflammation.

Acetaminophen mitigates myocardial injury induced by lower extremity ischemia-reperfusion in rat model

Abstract Objective: The injury-reducing effect of acetaminophen, an effective analgesic and antipyretic on ischemia-reperfusion continues to attract great attention. This study analyzed the protective effect of acetaminophen on myocardial injury induced by ischemia-reperfusion in an experimental animal model from lower extremity ischemia-reperfusion. Methods: Twenty-four Sprague-Dawley female rats were randomized into three groups (n=8) as (i) control group (only laparotomy), (ii) aortic ischemia-reperfusion group (60 min of ischemia and 120 min of reperfusion) and (iii) ischemia-reperfusion + acetaminophen group (15 mg/kg/h intravenous acetaminophen infusion starting 15 minutes before the end of the ischemic period and lasting till the end of the reperfusion period). Sternotomy was performed in all groups at the end of the reperfusion period and the heart was removed for histopathological examination. The removed hearts were histopathologically investigated for myocytolysis, polymorphonuclear leukocyte (PMNL) infiltration, myofibrillar edema and focal hemorrhage. Results: The results of histopathological examination showed that acetaminophen was detected to particularly diminish focal hemorrhage and myofibrillar edema in the ischemia-reperfusion + acetaminophen group (P<0.001, P=0.011), while there were no effects on myocytolysis and PMNL infiltration between the groups (P=1.000, P=0.124). Conclusion: Acetaminophen is considered to have cardioprotective effect in rats, by reducing myocardial injury induced by abdominal aortic ischemia-reperfusion.

Does platelet activity play a role in the pathogenesis of idiopathic ischemic priapism?

ABSTRACT Purpose Mean platelet volume (MPV) is used to measure platelet size and is defined as a potential marker of platelet reactivity. Higher MPV levels have been defined as a risk factor for increased incidence of intravascular thrombosis and its associated diseases. We aimed to determine whether a relationship exists between the MPV and veno-occlusive component of idiopathic ischemic priapism (IIP). Materials and methods Between 2010 and 2014, 38 subjects were analyzed in two groups. One was composed of 15 patients with diagnosis as IIP in our institute, and the other contained 23 healthy control subjects. Complete blood count reports were retrospectively evaluated in both groups. MPV, platelet count (PLT), platelet distribution width (PDW), white blood cells (WBC), red blood cells (RBC), hemoglobin (Hb), reticulocyte distribution width (RDW) were measured in both groups. : Results The mean ages were similar in IIP patients (45.86±15.82) and control subjects (47.65±10.99). The mean MPV values of IIP patients were significantly higher than control subjects (p<0.05). In contrast, also PLT counts were significantly lower in IIP patients, compared to control subjects (p<0.05). The mean hemoglobin and WBC values were significantly lower in control group (p<0.05). There was no significant difference of RBC, PDW and RDW values in both groups. Conclusions We found that the MPV was significantly higher in IIP patients compared to control subjects. The high MPV levels may have contributed to the veno-occlusive etiopathogenesis of IIP disease. We strongly suggest further prospective studies to recommend the use of MPV in routine practice.

Renal biomarkers of male and female Wistar rats (Rattus norvegicus) undergoing renal ischemia and reperfusion

PURPOSE: To investigate biomarkers of acute renal injury in Wistar rats, subjected to left renal ischemia for 10 minutes, and then compare reperfusion at 24 hours, and at 5, 7, 14 and 21 days after the procedure. METHODS: Eight female and male rats between 60 and 81 days old were used in the Central Animal Facility of the UFMS. Assessed biomarkers included urine protein, urea, creatinine, glucose, sodium, potassium, urine alkaline phosphatase and gamma-glutamyl transferase activities, and protein-to-creatinine ratio; and in serum: urea, creatinine, sodium and potassium, fractional excretion of sodium, potassium, urine flow and creatinine clearance. RESULTS: Greater variance was observed in the parameters at 24 hours and at five days (p<0.05) after reperfusion. On the 21st day, these parameters approximated those obtained for the control group. CONCLUSIONS: Renal ischemia for 10 minutes was sufficient to raise urine levels of protein, glucose, fractional excretion of potassium, urea, creatinine clearance, urine activity of gamma-glutamyltransferase and alkaline phosphatase enzymes in the first 24 hours, up to five days after reperfusion, which may indicate risk of acute kidney injury, according to the RIFLE classification. .

Evaluation of the effects of ischemic preconditioning on the hematological parameters of rats subjected to intestinal ischemia and reperfusion

OBJECTIVES: Intestinal ischemia/reperfusion often leads to acute lung injury and multiple organ failure. Ischemic preconditioning is protective in nature and reduces tissue injuries in animal and human models. Although hematimetric parameters are widely used as diagnostic tools, there is no report of the influence of intestinal ischemia/reperfusion and ischemic preconditioning on such parameters. We evaluated the hematological changes during ischemia/reperfusion and preconditioning in rats. METHODS: Forty healthy rats were divided into four groups: control, laparotomy, intestinal ischemia/reperfusion and ischemic preconditioning. The intestinal ischemia/reperfusion group received 45 min of superior mesenteric artery occlusion, while the ischemic preconditioning group received 10 min of short ischemia and reperfusion before 45 min of prolonged occlusion. A cell counter was used to analyze blood obtained from rats before and after the surgical procedures and the hematological results were compared among the groups. RESULTS: The results showed significant differences in hematimetric parameters among the groups. The parameters that showed significant differences included lymphocyte, white blood cells and granulocyte counts; hematocrit; mean corpuscular hemoglobin concentration; red cell deviation width; platelet count; mean platelet volume; plateletcrit and platelet distribution width. CONCLUSION: The most remarkable parameters were those related to leukocytes and platelets. Some of the data, including the lymphocyte and granulocytes counts, suggest that ischemic preconditioning attenuates the effect of intestinal ischemia/reperfusion on circulating blood cells. Our work contributes to a better understanding of the hematological responses after intestinal ischemia/reperfusion and IPC, and the present findings may also be used as predictive values. .

Isquemia grave de membros inferiores por arterite por HIV / Severe ischemia of lower limbs due to arteritis caused by HIV infection

A isquemia aguda de membros pode se manifestar, embora de forma incomum, como consequência à vasculite associada ao vírus da imunodeficiência humana (HIV). O presente caso descreve a evolução de uma paciente soropositiva para o HIV, que apresentou quadro de isquemia distal bilateral, com diminuição da temperatura de terço distal das pernas e pés, dor intensa, cianose fixa de pododátilos e ausência de pulsos distais. Submetida ao tratamento com terapia trombolítica, apresentou sinais de lesões decorrentes da isquemia e lesão tecidual de reperfusão com perda tecidual em regiões distais dos dedos, porém com melhora dos sinais e sintomas dos membros inferiores. Trata-se de um caso raro na literatura em função da associação da vasculite com o HIV e do acometimento dos vasos distais nos membros inferiores. Entretanto, o conhecimento desta associação é de extrema importância devido à repercussão na vida dos pacientes acometidos.

The acute limb ischemia may manifest itself, albeit unusual, as a consequence of vasculitis associated with human immunodeficiency virus (HIV). This case report described a patient seropositive for HIV who developed bilateral distal ischemia with temperature decrease of distal legs and feet, severe pain, cyanosis of fixed toes, and absence of distal pulses. She underwent treatment with thrombolytic therapy, showed signs of injury resulting from ischemia and reperfusion tissue injury with tissue loss in the distal regions of the fingers, but with improvement of the signs and symptoms of lower limbs. It is a rare case in literature due to the association of vasculitis with HIV and to the torment of distal vases of the lower limbs. Despite of that, the knowledge of the pathology is extremely important because of the repercussion in the patients' lives.

Effect of short-term ornithine alpha-ketoglutarate pretreatment on intestinal ischemia-reperfusion in rats / Efeitos do pré-tratamento em curto prazo com ornitina alfa-cetoglutarato na isquemia-reperfusão intestinal em ratos

PURPOSE: To investigate the effects of preventive enteral administration of ornithine alpha-ketoglutarate (OKG) in an ischemia-reperfusion rat model. METHODS: Sixty rats were randomized into five groups (G1-G5, n = 12). Each group was divided into two subgroups (n = 6) and treated with calcium carbonate (CaCa) or OKG by gavage. Thirty minutes later, the animals were anesthetized with xylazine 15mg + ketamine 1mg ip and subjected to laparotomy. G1-G3 rats served as controls. Rats in groups G4 and G5 were subjected to ischemia for 30 minutes. Ischemia was achieved by clamping the small intestine and its mesentery, delimiting a segment of bowel 5 cm long and 5 cm apart from the ileocecal valve. In addition, G5 rats underwent reperfusion for 30 minutes. Blood samples were collected at the end of the laparotomy (G1), after 30 minutes (G2, G4) and 60 minutes (G3, G5) to determine concentrations of metabolites (pyruvate, lactate), creatine phosphokinase (CPK), thiobarbituric acid reactive substances (TBARS) and glutathione (GSH). RESULTS: There was a significant decrease in tissue pyruvate and lactate and plasma CPK levels in OKG-treated rats at the end of reperfusion period. GSH levels did not change significantly in ischemia and reperfusion groups. However, TBARS levels increased significantly (p<0.05) in tissue samples in OKG-treated rats subjected to ischemia for 30 minutes. CONCLUSION: Short-term pretreatment with OKG before induction of I/R decreases tissue damage, increases pyruvate utilization for energy production in the Krebs cycle and does not attenuate the oxidative stress in this animal model.

OBJETIVO: Investigar os efeitos da administração enteral preventiva de ornitina alfa-cetoglutarato (OKG) em modelo de isquemia-reperfusão no rato. MÉTODOS: Sessenta ratos foram randomizados em cinco grupos (G1-G5, n=12). Cada grupo foi redistribuído em dois subgrupos (n=6) e tratado com carbonato de cálcio (CaCa) ou OKG por gavagem. Trinta minutos mais tarde, os animais foram anestesiados com xilazina 1mg+cetamina 15mg i.p. e submetidos à laparotomia. Os ratos dos grupos G4-G5 foram submetidos à isquemia por 30 minutos. A isquemia foi obtida por pinçamento do intestino delgado, delimitando um segmento com 5 cm de comprimento e distando 5 cm da válvula ileocecal. O grupo G5 foi submetido à reperfusão por 30 minutos. Amostras de sangue foram coletadas no final da laparotomia (G1), após 30 minutos (G2, G4) e 60 minutos (G3, G5) para determinação das concentrações de metabolitos (piruvato, lactato), creatinofosfoquinase (CPK), substâncias reativas ao ácido tiobarbitúrico (TBARS) e glutationa (GSH). RESULTADOS: Observou-se redução significante (p<0,05) das concentrações de piruvato e lactato, teciduais e CPK plasmático em ratos tratados com OKG, no final do período de reperfusão. Não houve alteração significante nos níveis plasmáticos e teciduais de GSH. Entretanto os níveis de TBARS aumentaram significativamente (p<0,05) em amostras de tecido de ratos tratados com OKG submetido à isquemia por 30 minutos. CONCLUSÃO: o pré-tratamento em curto prazo com OKG antes da indução da I/R diminui a lesão tecidual, aumenta a utilização de piruvato para produção de energia no ciclo de Krebs, mas não atenua o estresse oxidativo neste modelo animal.

Oxidized low-density lipoprotein and ankle-brachial pressure index in patients with clinically evident peripheral arterial disease

OBJECTIVES: To investigate whether oxidized low-density lipoprotein is a suitable predictor of peripheral arterial disease severity. The role of oxidized low-density lipoprotein in the pathogenesis of atherosclerosis has already been investigated. Its relevance as a predictor of the appearance and worsening of coronary arterial disease is also well known. However, the same is not true regarding peripheral arterial disease. METHOD: Eighty-five consecutive patients with an ankle-brachial pressure index (ABPI) < 0.9 and the presence of either intermittent claudication or critical lower leg ischemia were included. The plasma level of IgG autoantibodies against oxidized low-density lipoprotein was evaluated through an enzyme-linked immunosorbent assay. The results were categorized into quartiles according to the ankle-brachial pressure index (a marker of peripheral arterial disease severity), and significant differences were investigated with the Kruskal-Wallis test. RESULTS: There was no significant difference between the quartiles for this population (p = 0.33). No correlation was found between the ankle-brachial pressure index and oxidized low-density lipoprotein levels in subjects with clinically evident peripheral arterial disease with a wide range of clinical manifestations. CONCLUSIONS: Oxidized low-density lipoprotein is not a good predictor of peripheral arterial disease severity.

Hematological and hemostaseological alterations after warm and cold limb ischemia-reperfusion in a canine model / Alterações hematológicas e hemostaseológicas após isquemia-reperfusão morna e fria de membro inferior em modelo canino

PURPOSE: Acute ischemia-reperfusion (I/R) of extremities means serious challenge in the clinical practice. Furthermore, the issue of preventive cooling is still controversial. In this canine model we investigated whether limb I/R -with or without cooling- has an influence on hematological and hemostaseological factors. METHODS: Femoral vessels were exposed and clamped for 3 hours. After release the clamps, 4-hour reperfusion was secured. The same procedures with cooling using ice bags, as well as warm and cold sham-operations were performed. Before operations, from the excluded limb by the end of ischemia, during the reperfusion, and for 5 postoperative days afterwards blood samples were collected for testing hematological and blood coagulation parameters. RESULTS: After I/R activated partial thromboplastin time was elongated on 2nd-4th postoperative days. The highest values were on the 2nd day in cold I/R group, accompanied by increased prothrombin time values. The hematological parameters and fibrinogen level showed non-specific changes. In excluded ischemic limb the blood composition showed controversial data. Cold ischemia induced larger alterations, however platelet count, hematocrit changed more expressly in warm ischemia. CONCLUSION: These results indicate the risk of coagulopathy following limb I/R on early post-eventually days, which risk is higher in the case of cold I/R.

OBJETIVO: Isquemia-Reperfusão aguda (I/R) de extremidades representa um desafio sério na prática clínica. Além disso, o tema de prevenção pelo resfriamento é ainda controverso. Nesse modelo canino, investigou-se se I/R de membros -com ou sem resfriamento- tem influência nos fatores hematológicos e hemostaseológicos. MÉTODOS: Os vasos femorais foram expostos e clampeados por 3 horas. Após liberação dos clampes, foi realizada a reperfusão por 4-horas. Os mesmos procedimentos com e sem resfriamento usando bolsas de gelo, assim como operações simuladas com e sem resfriamento foram realizados. Antes das operações, do membro excluído ao final da isquemia, durante a reperfusão e por 5 dias de pós-operatório, amostras sanguíneas foram colhidas para exames hematológicos e parâmetros de coagulação. RESULTADOS: Após I/R, o tempo de tromboplastina parcial ativada foi alargado no 2º.-4º. dias de pós-operatório. Os valores mais altos foram no 2º.dia no grupo deI/R fria, acompanhada pelo aumento dos valores do tempo de protrombina. Os parâmetros hematológicos e o nível de fibrinogênio mostraram mudanças não específicas. No membro isquêmico excluído a composição sanguínea mostrou dados controversos. A isquemia fria induziu maiores alterações, entretanto, a contagem de plaquetas e o hematócrito mudaram mais expressivamente na isquemia morna. CONCLUSÃO: Estes resultados indicam risco de coagulopatia após I/R de membros nos dias mais precoces após o evento, sendo mais elevado no caso da I/R fria.

Efeito do óleo de copaíba nos níveis séricos de uréia e creatinina em ratos submetidos à síndrome de isquemia e reperfusão renal / Copaiba oil effect on urea and creatinine serum levels in rats submitted to kidney ischemia and reperfusion syndrome

OBJETIVO: Avaliar o efeito do óleo de copaíba nos níveis séricos de uréia e creatinina em ratos submetidos a síndrome de isquemia e reperfusão renal. MÉTODOS: Foram utilizados 18 ratos (Rattus norvegicus albinus),da linhagem Wistar, fêmeas, adultas, entre 90 e 120 dias de idade, pesando ente 200g e 250g, distribuídos em dois grupos: Isquemia e Reperfusão (GIR), e Isquemia e Reperfusão Copaíba (GIRC). Os animais dos dois grupos foram submetidos à isquemia renal, de ambos os rins, por 50 minutos, seguida de reperfusão por 24, 48 e 72 horas, com posterior coleta de sangue e análise dos níveis séricos de uréia e creatinina. No GIRC, realizou-se, além da isquemia e reperfusão, a administração diária do óleo de copaíba na dose de 0,63 ml/kg, por gavagem, sete dias antes do procedimento de isquemia renal. RESULTADOS: Foi observada uma diminuição estatisticamente significante dos níveis séricos de uréia no GIRC em 24 e 48 horas de reperfusão renal e uma diminuição do nível sérico de creatinina no GIRC em 48 horas de reperfusão renal quando comparados com o grupo Controle. CONCLUSÃO: Segundo os procedimentos aplicados, o óleo de copaíba diminuiu os níveis séricos de uréia em 24 horas e 48 horas e os de creatinina nas 48 horas após o procedimento de isquemia e reperfusão renal em ratos.

Alterações metabólicas induzidas por isquemia hepática normotérmica experimental e o efeito hepatoprotetor da ciclosporina / Induced metabolic alterations due to experimental normothermic hepatic ischemia and the hepatoprotector effect of cyclosporin

RACIONAL: Transplante de fígado é inevitavelmente associado com períodos de isquemia completa. No entanto, o tempo de oclusão do pedículo hepático é limitado pelas conseqüências da injúria pós-isquêmica do fígado. OBJETIVO: Determinar as principais alterações metabólicas ocasionadas pela isquemia hepática e a provável ação hepatoprotetora da ciclosporina. MÉTODOS: Isquemia hepática normotérmica por 60 minutos foi induzida em ratos. Em seguida, as alterações com o tempo (0, 1, 6, 24 horas) das concentrações sangüíneas e hepáticas de lactato, piruvato, glicose, corpos cetônicos e razão acetoacetato/3-hidroxibutirato, bem como o estado redox citoplasmático e mitocondrial do tecido hepático foram determinados. Outro grupo de animais foi pré-tratado com ciclosporina (10 mg/kg), sendo estudadas as alterações metabólicas no tempo 1 hora após revascularização hepática. RESULTADOS: A isquemia hepática causou elevação da concentração de lactato no fígado, sugerindo que pronunciado grau de metabolismo anaeróbico ocorreu durante o período de isquemia. Isquemia hepática acarretou ainda queda da concentração e da razão dos corpos cetônicos (acetoacetato/3-hidroxibutirato) no sangue arterial no tempo de 1 hora após revascularização. Tal fato reflete que a injuria isquêmica do fígado interfere na cetogênese. CONCLUSAO: O tratamento com ciclosporina causa elevação das concentrações dos corpos cetônicos e da razão acetoacetato/3-hidroxibutirato no sangue arterial após 1 hora de reperfusão hepática, sugerindo que esta droga acelera a cetogênese e, conseqüentemente, a recuperação da lesão isquêmica do fígado.