Scielo RSS <![CDATA[Acta Cirurgica Brasileira]]> vol. 32 num. 8 lang. en <![CDATA[SciELO Logo]]> <![CDATA[Perconditioning combined with postconditioning on kidney ischemia and reperfusion]]> Abstract Purpose: To evaluate if combination of perconditioning and postconditioning provides improved renal protection compared to perconditioning alone in a model of renal reperfusion injury. Methods: Thirty rats were assigned into 6 groups: normality; sham; ischemia and reperfusion; postconditioning; perconditioning; perconditioning + postconditioning. Animals were subjected to right nephrectomy and left renal ischemia for 30 minutes. Postconditioning consisted of 3 cycles of 5 min renal perfusion followed by 5 min of renal ischemia after major ischemic period. Perconditioning consisted of 3 cycles of 5 min hindlimb ischemia followed by 5 min of hindlimb perfusion contemporaneously to renal major ischemic period. After 24 hours, kidney was harvested and blood collected to measure urea and creatinine. Results: Perconditioning obtained better values for creatinine and urea level than only postconditioning (p&lt;0.01); performing both techniques contemporaneously had no increased results (p&gt;0.05). Regarding tissue structure, perconditioning was the only technique to protect the glomerulus and tubules (p&lt;0.05), while postconditioning protected only the glomerulus (p&lt;0.05). Combination of both techniques shows no effect on glomerulus or tubules (p&gt;0.05). Conclusions: Perconditioning had promising results on ischemia and reperfusion induced kidney injury, enhanced kidney function and protected glomerulus and tubules. There was no additive protection when postconditioning and perconditioning were combined. <![CDATA[Corneal angiogenesis based on different protocols of alkaline cauterization in murine models]]> Abstract Purpose: To establish and compare protocols of alkaline cauterization for inducing corneal angiogenesis in murine models. Methods: Twenty-four adult Wistar rats were distributed into four groups (G1, G2, G3, and G4). The right eye cornea from each rat was cauterized using filter paper (3 mm), soaked in a solution of silver and potassium nitrates (3:1). Cauterization times were 10 (G1 and G4), or 20 seconds (G2 and G3). Cauterized corneas were washed with Ringer’s lactate solution. The filter paper was either removed before washing (G1 and G2), or kept on the corneas (G3 and G4). Corneas were photographed at multiple time points (2, 4, 6, 8, 11, 13, and 15 days after the procedure), and neovascularization parameters were assayed. Results: Neovascularization was observed in 66% of G1 corneas, and 100% of G2, G3, and G4 corneas. On day 15, G1 corneas showed smaller vascularized areas (12.63 ± 12.59%) compared to those in the G3 (41.95 ± 17.32%) and G4 (33 ± 11.74%) (P &lt; 0.05) groups. Conclusions: The silver and potassium nitrate solution effectively induced corneal angiogenesis. The G2, G3, and G4 protocols showed excellent reproducibility, and induced vascularization in 100% of corneas. <![CDATA[Inside-out and standard vein grafts associated with platelet-rich plasma (PRP) in sciatic nerve repair. A histomorphometric study]]> Abstract Purpose: To evaluated the tubulization technique with standard and inside-out vein, filled or not with platelet-rich plasma (PRP), in sciatic nerve repair. Methods: Seventy male Wistar rats were randomly divided into five groups: IOVNF (Inside-Out Vein with No Filling); IOVPRP (Inside-Out Vein filled with PRP); SVNF (Standard Vein with No Filling); SVPRP (Standard Vein filled with PRP); Sham (Control). The left external jugular vein was used as graft in a 10 mm nervous gap. Results: In the morphological analysis of all groups, myelinated nerve fibers with evident myelin sheath, neoformation of the epineurium and perineurium, organization of intraneural fascicles and blood vessels were observed. In the morphometry of the distal stump fibers, SVPRP group had the highest means regarding fiber diameter (3.63±0.42 μm), axon diameter (2.37±0.31 μm) and myelin sheath area (11.70±0.84 μm2). IOVPRP group had the highest means regarding axon area (4.39±1.16 μm2) and myelin sheath thickness (0.80±0.19 μm). As for values of the fiber area, IOVNF group shows highest means (15.54±0.67 μm2), but are still lower than the values of the Sham group. Conclusion: The graft filled with platelet-rich plasma, with use standard (SVPRP) or inside-out vein (IOVPRP), promoted the improvement in axonal regeneration on sciatic nerve injury. <![CDATA[Evaluation of the effectiveness of sodium hyaluronate, sesame oil, honey, and silver nanoparticles in preventing postoperative surgical adhesion formation. An experimental study]]> Abstract Purpose: To evaluate the effectiveness of sodium hyaluronate, sesame oil, honey, and silver nanoparticles in preventing of postoperative surgical adhesion formation. Methods: Forty male Wistar rats were randomly assigned into five groups with eight rats in each group including control, hyaluronate, sesame, honey and silver groups. After two weeks the animals underwent laparotomy and were evaluated by two different blinded surgeons for severity of adhesions based on the two different classification scoring systems including Nair classification and cumulative adhesion scoring scale. Results: The scores of severity of adhesions in the hyaluronate and sesame groups were significantly lower than the control group based on the Nair classification (both P-values = 0.02), however based on the cumulative adhesion scoring scale just the score of severity of adhesions in the hyaluronate group was significantly lower than the control group (P-value = 0.02). In the hyaluronate group the severity of adhesions was decreased by 48% based on the cumulative adhesion scoring scale. Conclusions: Sodium hyaluronate and sesame oil may have a significant effect in preventing postoperative surgical adhesion formation. <![CDATA[Hyperin protects against cisplatin-induced liver injury in mice]]> Abstract Purpose: To evaluate the effect of hyperin in cisplatin-induced liver injury in mice. Methods: Mice were pretreated with hyperin at doses of 25 mg/kg and 50 mg/kg, respectively, for six days, and intraperitoneal injection of cisplatin (40 mg/kg) was administrated one hour after the final intragastrication of hyperin. Twenty-four hours later, blood and liver were collected for further research. Results: A single injection of cisplatin (40 mg/kg) for 24 h significantly increased serum alanine and aspartate aminotransferases (ALT/AST) and gamma glutamyl transferase (GGT) activities, whileas hyperin reversed cisplatin-induced such increases. Liver histopathological examination further demonstrated the protection of hyperin against cisplatin-induced liver injury. Further results showed hyperin reversed cisplatin-induced the increase in content of malondialdehyde (MDA) and the decrease in level of total antioxidant capacity (T-AOC) in liver. Moreover, hyperin increased the levels of superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), glutathione peroxidase (GPx), glutathione-s transferase (GST) in cisplatin-induced liver. Conclusion: Hyperin inhibits cisplatin-induced hepatic oxidative stress, which contributes greatly to the amelioration of cisplatin-induced liver injury in mice. <![CDATA[Bacterial translocation and mortality on rat model of intestinal ischemia and obstruction]]> Abstract Purpose: To develop an experimental model of intestinal ischemia and obstruction followed by surgical resection of the damaged segment and reestablishment of intestinal transit, looking at bacterial translocation and survival. Methods: After anesthesia, Wistar rats was subject to laparotomy, intestinal ischemia and obstruction through an ileal ligature 1.5cm of ileum cecal valve; and the mesenteric vessels that irrigate upstream of the obstruction site to approximately 7 to 10 cm were ligated. Abdominal wall was closed. Three, six or twenty-four hours after, rats were subject to enterectomy followed by an end to end anastomosis. After 24h, mesenteric lymph nodes, liver, spleen and lung tissues were surgically removed. It was studied survival rate and bacterial translocation. GraphPadPrism statistical program was used. Results: Animals with intestinal ischemia and obstruction for 3 hours survived 24 hours after enterectomy; 6hx24h: survival was 70% at 24 hours; 24hx24h: survival was 70% and 40%, before and after enterectomy, respectively. Culture of tissues showed positivity on the 6hx24h and negativity on the 3hx24h. Conclusion: The model that best approached the clinic was the one of 6x24h of ischemia and intestinal obstruction, in which it was observed bacterial translocation and low mortality rate. <![CDATA[Intestinal inflammatory and redox responses to the perioperative administration of teduglutide in rats]]> Abstract Purpose: To investigate the inflammatory and redox responses to teduglutide on an animal model of laparotomy and intestinal anastomosis. Methods: Wistar rats (n=62) were allocated into four groups: “Ileal Resection and Anastomosis” vs. “Laparotomy”, each one split into “Postoperative Teduglutide Administration” vs. “No Treatment”; and euthanized at the third or the seventh day. Ileal and blood samples were recovered at the baseline and at the euthanasia. Flow cytometry was used to study the inflammatory response (IL-1α, MCP-1, TNF-α, IFN-γ and IL-4 levels), oxidative stress (cytosolic peroxides, mitochondrial reactive species, intracellular glutathione and mitochondrial membrane potential) and cellular viability and death (annexin V/propidium iodide double staining). Results: Postoperative teduglutide treatment was associated with higher cellular viability index and lower early apoptosis ratio at the seventh day; higher cytosolic peroxides level at the third day and mitochondrial overgeneration of reactive species at the seventh day; higher tissue concentration of IL-4 and lower local pro-to-anti-inflammatory cytokines ratio at the seventh day. Conclusion: Those findings suggest an intestinal pro-oxidative and anti-inflammatory influence of teduglutide on the peri-operative context with a potential interference in the intestinal anastomotic healing. <![CDATA[A study on reducing the absorption of lidocaine from the airway in cats]]> Abstract Purpose: To determine if the combination of lidocaine with epinephrine or gamma globulin would decrease the rate or reduce the amount of local absorption of lidocaine through the airway. Methods: Twenty adult male cats were randomly and evenly distributed into four groups: 1) Group LG: lidocaine administered with gamma globulin; 2) Group LS: lidocaine administered with physiological saline); 3) Group LE: lidocaine administered with epinephrine; 4) Group C: control group. Invasive blood pressure, heart rate, and concentration of lidocaine were recorded before and after administration. Results: The peak of plasma concentrations appeared difference (Group LG: 1.39 ± 0.23 mg/L; Group LS: 1.47 ± 0.29 mg/L and Group LE: 0.99 ± 0.08 mg/L). Compared to Group C, there were significant differences in the average heart rate of Groups LG, LS, and LE (P &lt; 0.05). The average systolic blood pressures were significantly different when each group was compared to Group C (P &lt; 0.05). The biological half-life, AUC0-120, peak time, and half-life of absorption among the three groups have not presented statistically significant differences (P &gt; 0.05). Conclusion: Administering lidocaine in combination with gamma globulin through airway causes significant decrease the rate and reduce the amount of local absorption of lidocaine in cats. <![CDATA[Use of fibrinogen and thrombin sponge in pediatric split liver transplantation]]> Abstract Purpose: To analyze the use of this sponge in pediatric patients undergoing split-liver transplantation. Methods: Retrospective study, including 35 pediatric patients undergoing split-liver transplantation, divided into two groups according to the use of the sponge: 18 patients in Group A (no sponge) and 17 in Group B (with sponge). Results: The characteristics of recipients and donors were similar. We observed greater number of reoperation due to bleeding in the wound area in Group A (10 patients - 55.5%) than in Group B (3 patients - 17.6%); p = 0.035. The median volume of red blood cells transfused in Group A was significantly higher (73.4 ± 102.38 mL/kg) than that in Group B (35.1 ± 41.67 mL/kg); p = 0.048. Regarding bile leak there was no statistical difference. Conclusion: The use of the human fibrinogen and thrombin sponge, required lower volume of red blood cell transfusion and presented lower reoperation rates due to bleeding in the wound area. <![CDATA[Fixation of the short-term central venous catheter. A comparison of two techniques]]> Abstract Purpose: To compare the fixation of the central venous catheter (CVC) using two suture techniques. Methods: A clinical, analytical, interventional, longitudinal, prospective, controlled, single-blind and randomized study in adult, intensive care unit (ICU) patients. After admission and indication of CVC use, the patients were allocated to the Wing group (n = 35, catheter fixation with clamping wings and retainers) or Shoelace group (n = 35, catheter fixation using shoelace cross-tied sutures around the device). Displacement, kinking, fixation failure, hyperemia at the insertion site, purulent secretion, loss of the device, psychomotor agitation, mental confusion, and bacterial growth at the insertion site were evaluated. Results: Compared with the Wing group, the Shoelace group had a lower occurrence of catheter displacement (n=0 versus n =4; p = 0.04), kinking (n=0 versus n=8; p=0.001), and fixation failure (n=2 versus n=8; p=0.018). No significant difference was found in bacterial growth (n=20 versus n=14; p=0.267) between groups. Conclusion: The Shoelace fixation technique presented fewer adverse events than the Wing fixation technique.