Resumo em Inglês:

PURPOSE: To compare fluid replacement therapy with Hydroxyethyl starch 6% (HES) versus Ringer's lactate (RL) in a rodent model of non-septic renal ischemia. METHODS: Forty male Wistar rats were randomized to receive HES 2 ml.kg-1.hr-1or RL 5 ml. kg-1.hr-1 that underwent 30 minutes of renal ischemia followed by reperfusion. Twelve hours after kidney ischemia, the kidneys were evaluated for histological changes. Serum NGAL levels were obtained at different times of the experimental protocol. RESULTS: Rodents in the HES group had a median (IQR) grade of renal injury 3 (3 to 5) compared to 2 (2 to 4) in the RL group (p=0.03). NGAL levels were not associated with the severity of kidney injury. CONCLUSION: Hydroxyethyl starch administration caused more kidney injury than Ringer's lactate in a non-infectious model of renal hypoperfusion.

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PURPOSE: To investigate the compatibility of a new model of self-expandable tracheal stent in rats. METHODS: A new device of polyurethane covered and non - covered stent was placed in the trachea of Wistar rats. Animals were distributed in two groups: the polyurethane covered and non-covered group. Macroscopic parameters included position within the tracheal lumen, adherence to the mucosa, degree of dilatation, permeability and internal diameter. Microscopic findings evaluated were: incorporation, inflammatory activity, granulation tissue and epithelial revetment injuries. The observation follow-up was six weeks. All parameters were quantified based on determined score values. Incorporation of the stents was evaluated based on the observation if the stent was fixed into the trachea or if it could be removed. Degree of dilatation was performed by external diameter measurements. Granulation tissue was evaluated by measurements of height of the tissue growing into the tracheal lumen. RESULTS: 100% of non-covered stents had total attachment to mucosa and 100% of polyurethane covered type had adherence only. Regarding dilatation, granulation tissue, inflammatory activity and internal diameter measurements, there were no significant differences between the groups. Pathological tracheal wall injuries were present in both groups. CONCLUSION: Both models of stent demonstrated biocompatibility with the trachea. Rats are suitable for an experimental model of tracheal stent study.

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PURPOSE: To evaluate the effect of nitroglycerine (NTG) on sensory and motor block onset and recovery time as well as the quality of tourniquet pain relief, when added to lidocaine (LID) for intravenous regional anesthesia in elective forearm and hand surgery. METHODS: A randomized double-blinded clinical trial was performed on 40 patients that were randomly allocated into two groups received lidocaine 3 mg/kg with NTG 200 µg or received only lidocaine 3 mg/kg as the control. RESULTS: There was no difference between the two study groups in hemodynamic parameters before tourniquet inflation, at any time after inflation and after its deflation. There was no difference in the mean of pain score over time between the two groups. The onset time of sensory and motor blockades was shorter in the group received both LID and NTG. The mean recovery time of sensory blockade was longer in the former group. The frequency of opioid injections was significantly lower in those who administered LID and NTG. CONCLUSION: The adjuvant drug of NTG when added to LID is effective in improving the overall quality of anesthesia, shortening onset time of both sensory and motor blockades, and stabling homodynamic parameters in hand and forearm surgery.

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PURPOSE: To comparatively study the efficacy and maternal and fetal side-effects of two doses of bupivacaine associated with morphine and clonidine, administered by the subarachnoid route for cesarean section. METHODS: The study included 66 pregnant women at term, distributed into two groups. GI: bupivacaine 8.0 mg (1.6mL) + clonidine 75µg (0.5mL) + morphine 100µg (1.0mL) and GII: bupivacaine 10mg (2.0mL) + clonidine 75µg (0.5mL) + morphine 100µg (1.0mL). The following parameters were assessed: onset and maximum level of sensory block; quality of intraoperative and postoperative analgesia; degree and duration of motor block; maternal repercussions and Apgar score. RESULTS: The onset of sensory block, quality of intraoperative analgesia and total duration of analgesia were similar in both groups; maximum extent of sensory block predominated in T4; maximum degree of motor block (Bromage 3); time motor block regression was significantly longer in GII; Hemodynamic, respiratory repercussions, adverse maternal effects and Apgar scores were similar between groups. In both groups, there was a predominance of drowsy or sleeping patients. CONCLUSION: The addition of morphine and clonidine to low doses of hyperbaric bupivacaine produced adequate anesthesia for cesarean section and good postoperative analgesia, without any maternal and fetal repercussions.

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PURPOSE: To assess the effects of unripe Musa sapientum peel on the healing of surgical wounds in rats. METHODS: One hundred and twenty Wistar rats were divided into two treatment groups of 60 animals each: the control group (gel without the active ingredient) and experimental group (4% Musa sapientum peel gel). A 4 x 4 cm surgical wound was created on the back of each animal. The wound was cleaned daily with 0.9% saline, treated with 4% gel or natrosol gel (control), and covered with gauze. Animals from both groups were sacrificed after seven, 14 and 21 days of treatment; the tissue from the wound site was removed together with a margin of normal skin for histological analysis. RESULTS: No significant differences in wound contraction rates (p=0.982) were found between time points (seven, 14 and 21 days of treatment) in both groups. However, a significantly higher wound contraction rate was observed in the control group on day 21 compared with the experimental group (p=0.029). There were no significant differences in histomorphological features between groups. The experimental group showed an increased number of polymorphonuclear cells on day 7, with a significant reduction on day 21 (p=0.026). CONCLUSION: The use of 4% unripe Musa sapientum peel gel on surgical wounds in rats resulted in an increased number of polymorphonuclear cells on day 7, reduced wound contraction, reduced vascular proliferation and increased concentration of collagen fibers on day 21.

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PURPOSE: To investigate the efficiency of electrical stimulation in the muscle maintenance and nerve regeneration after end-to-side neurorrhaphy (ESN). METHODS: Sixty male Wistar rats (Rattus norvegicus) were divided into four experimental groups. Control group (Control), Denervated Group (Denervated); Group with End-to-side neurorrhaphy (ESN); Group with End-to-side neurorrhaphy and electrical stimulation (ESN + ES). We perform electrical stimulation in rats after they had undergone muscle reinnervation by ESN. We collected morphometric and functional data. RESULTS: When comparing the mass of the treated side of cranial tibial muscle (CTM) and that of normal side of CTM, the group ESN + ES (26.12%) exhibited lower mass loss than that of group ESN (37.23%). The peroneal functional index showed that group ESN + ES equaled that of the Control group and showed an evolution of 60.5% while group ESN showed an evolution of 9.5%. In measuring maximum strength of CTM, the group ES + ESN outperformed group ESN. The muscle and nerve morphometry showed superiority of group ES+ESN over ESN group in all parameters. CONCLUSION: Electrical stimulation is an effective means of maintaining functional muscle and nerve regeneration after end-to-side neurorrhaphy.

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PURPOSE: To evaluate the relationship between microvascular density and the expression of vascular endothelial growth factor (VEGF) and KIT as possible markers of angiogenic stimulus in astrocytic tumors and correlate it with histopathological grading. METHODS: We enrolled 99 surgical specimens of supratentorial astrocytic tumors for analysis of VEGF and KIT and subsequent correlation with MVD and grading. RESULTS: KIT and VEGF expression correlated with microvascular density (p<0.005) and both VEGF and microvascular density correlated with grading (p<0.005). KIT had no significant relationship with grading (p=0.657). CONCLUSION: KIT and VEGF constitute important pathways in the angiogenesis of astrocytomas and therefore are promising prognostic tools and options for therapeutic intervention.

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PURPOSE: To analyze the intraoperative and immediate postoperative biochemical parameters of patients submitted to orthotopic liver transplantation. METHODS: Forty four consecutive orthotopic liver transplants performed from October 2009 to December 2010 were analyzed. The patients (38 male and eight female) were divided into two groups: group A, survivors, and group B, non-survivors. Fifty percent of group A patients were Chid-Pugh C, 40% Chid-Pugh B and 10% Chid-Pugh A. In group B, 52% of the patients were Chid-Pugh C, 41% Chid-Pugh B, and 17% Chid-Pugh A. All orthotopic liver transplants were performed by the piggy-back technique without a portacaval shunt in an anhepatic phase. ALT, AST, LDH and lactate levels were determined preoperatively, at five, 60 minutes after arterial revascularization of the graft and 24 and 48 hours after the end of the surgery.( or: after the surgery was finished). RESULTS: There were no preoperative clinical differences (Child and Meld) between the two groups. The times of warm and hypothermal ischemia were similar for both groups (p>0.05). Serum aminotransferases levels at five and 60 minutes after arterial revascularization of the graft were similar (p>0.05) for both groups, as also were lactate levels at the time points studied. There was no significant difference in Δ lactate between groups at any time point studied (p>0.05). No significant difference was observed between groups during the first 24 and 48 hours after surgery (p>0.05). CONCLUSION: No significant difference in any of the parameters studied was observed between groups. Under the conditions of the present study and considering the parameters evaluated, no direct relationship was detected between the intraoperative situation and the type of evolution of the patients of the two groups studied.

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PURPOSE: To assess pregnancy of rabbits submitted to bilateral ovariectomy and orthotopic allogeneic or autologous intact and sliced ovarian transplantation without a vascular pedicle and to determine the morphofunctional aspects of the transplanted ovaries. METHODS: Fifty-six female rabbits were studied. The ovaries were removed and orthotopically transplanted or replaced without vascular anastomoses: Group 1 (n=8), only laparotomy and laparorrhaphy, Group 2A (n=8) intact ovaries were transplanted on both sides, Group 2B (n=8) both ovaries were sliced and orthotopically transplanted, Group 2C (n=8), an intact ovary was transplanted on one side and a sliced ovary on the other side. In Group 3 the ovaries were reimplanted according to the procedure and subgroups described for Group 2. Three months later, the animals were paired with males for copulation. Estradiol, progesterone, FSH and LH hormone levels were assessed. A histologic study was carried out, and the number of pregnancies and litters were also determined. Chi-square test compared the number of pregnancies and litters. One-way ANOVA and the Tukey-Kramer tests compared the hormonal dosages. RESULTS: Pregnancies occurred in seven (87.5%) rabbits of Group 1, in three rabbits (37.5%) of Groups 2A and 3A, in four rabbits (50%) of groups 2B, 3B and 3C, and in five (62.5%) of group 2C. Normal hormone serum levels and histology confirmed the vitality of all ovaries. CONCLUSION: Orthotopic allogeneic and autologous ovarian transplantation without a vascular pedicle is viable in rabbits, and preserves their hormonal levels and fertile functions.

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PURPOSE: To compare three sterilization methods (autoclave, gamma irradiation and ethylene oxide) over non demineralized lyophilized bone allografts. METHODS: Bone allografts were implanted on paravertebral muscles of 21 rats. After 30 days animals were sacrificed and grafts underwent comparative analysis regarding histomorphometric and macroscopic parameters. RESULTS: Allografts that underwent the three sterilization methods presents similar weight gain, cortical thickness similar to control group, and less fibrosis than the control group. Grafts that underwent sterilization in autoclave presented less presence of multinucleated giant cells, although not statistically significant. There was also no statistically significant difference regarding mineralization on the three groups. CONCLUSION: The three sterilization methods cause similar effects on bone allografts regarding macroscopic and histomorphometric parameters.

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PURPOSE: To investigate the effects of preoperative fractioned irradiation using an electron beam on the healing process of colocolonic anastomoses in rats that underwent early and late surgical intervention. METHODS: Thirty Wistar rats, distributed as follows: group A (surgery only), group B (fractionated irradiation for 30 days (if), surgery seven days after the end of it), group C (if for 30 days, and surgery after 30 days of termination). On the seventh postoperative day the anastomotic segment analysis was taken, using tension tests, histology and collagen deposition evaluation by computerized analysis. RESULTS: Regarding the tension resistance of the anastomosis, there were no statistical differences (p=0.42). However, a significant increase in cells number in the inflammatory infiltrate in the group with a longer interval between surgery and pre op radiation (p<0.05). The collagen concentration had no significant variance. CONCLUSION: The irradiation in divided doses increased local inflammatory cellularity when the surgery was performed later. This result did not affect the increase of complications, nor on the local concentration of collagen, achieving similar clinical outcomes.

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PURPOSE: To conduct a systematized review of the literature about the main local hemostatic measures to control postoperative bleeding in anticoagulated patients. METHODS: A systematized review of literature was performed in the electronic database Medline (PubMed) without restriction of the publication date. The eligibility criteria were studies involving maintenance of the anticoagulant therapy, prospective studies, retrospective studies, randomized clinical trials, controlled clinical studies, comparative studies, multicentric studies or case-control studies. Studies discontinuing anticoagulant therapy, case reports, literature reviews, in vitro studies, animal experiments and articles written in language not compatible with the search strategy adopted in this work were excluded. RESULTS: Twenty-four articles that met the adopted eligibility criteria were selected, enrolling 3891 subjects under anticoagulant therapy. A total of 171 cases of hemorrhage was observed. Tranexamic acid was the main local hemostatic measure used to controlling of postoperative bleeding. CONCLUSION: The local hemostatic measures proved to be effective according to previously published studies. Nevertheless, further clinical studies should be conducted to confirm this effectiveness.

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PURPOSE: To evaluate the quality of abstracts of original non-experimental research articles in Brazilian Journals in Surgery. METHODS: Convenience sample of 471 abstracts of original research articles from six Brazilian surgical journals indexed in Thomson Reuters (ISI) Web of Knowledge. The quality of abstracts was measured against a checklist of eight evaluation criteria, which were divided into 32 categories. The total score for each abstract was obtained by summing the score of all criteria present. The overall mean score was also determined. RESULTS: The overall mean score of abstract quality was that of a good abstract. Most of the abstracts contained some information from each of the eight basic categories of an abstract. All abstracts were structured ones. CONCLUSION: The overall quality, for abstracts of original articles of six Brazilian non-experimental journals in surgery, was classified as good.