Helena Vala

Evaluation of renal injury caused by acute volume replacement with hydroxyethyl starch 130/0.4 or Ringer's lactate solution in pigs

This work aimed to evaluate the effects on renal tissue integrity after hydroxyethyl starch (HES) 130/0.4 and Ringers lactate (RL) administration in pigs under general anesthesia after acute bleeding. A total of 30 mL/kg of blood were passively removed from the femoral artery in two groups of Large White pigs, under total intravenous anesthesia with propofol and remifentanil. After bleeding, Group 1 (n = 11) received RL solution (25 mL/kg) and Group 2 (n = 11) received HES 130/0.4 solution (20 mL/kg). Additionally, Group 3 (n = 6) was not submitted to bleeding or volume replacement. Pigs were euthanized and kidneys were processed for histopathological and immunohistochemical analyses. Minimal to moderate glomerular, tubular, and interstitial changes, as well as papillary necrosis, were observed in all experimental groups. Pre-apoptosis and apoptosis indicators were higher in pigs that received HES 130/0.4, indicating a higher renal insult. Both HES 130/0.4 and RL administration may cause renal injury, although renal injury may be more significant in pigs receiving HES 13/0.4. Results also suggest that total intravenous anesthesia with propofol and remifentanil may cause renal injury, and this effect can be dose related.

Renal Apoptosis Signalling in a Pig Haemorrhagic Model after Volume Replacement with HES 130/0.4 or Ringer's Solution

RENAL APOPTOSIS SIGNALLING IN A PIG HAEMORRHAGIC MODEL AFTER VOLUME REPLACEMENT WITH HES 130/0.4 OR RINGER’S SOLUTION R. Cruz*,y,z, H. Vala*,y, A. Machado*,y, C. Venâncio z, J.R. Mesquita*,y, A. Silva x, A.L. Ortiz{ and D. Ferreira *ESAV, IPV, yCI&DETS, IPV, zUTAD, xREQUIMTE, Portugal, {Le on University, Spain and CICV/FMV-ULHT, Portugal Introduction: TUNEL labelling is one of the most frequently used methods to detect apoptosis in renal tissues. The aim of this study was to evaluate kidney damage after acute haemorrhage and volume replacement with a colloid or a crystalloid, in a pig model. Materials and Methods: In accord with animal welfare regulations, three groups (n 5 6) of large white pigs were enrolled in the study. All groups underwent total intravenous anaesthesia and were subjected to acute haemorrhage and volume replacement with Ringer’s lactate or HES 130/0.4, 20 min after haemorrhage. Control pigs did not undergo bleeding and volume replacement. Pigs were killed and renal samples were taken and analyzed by the TUNEL method. ANOVA was used to compare data between groups. Results: An intense positive signal in tubular epithelial cells was observed in all samples. The level of signalling per mm was significantly lower in the group receiving Ringer’s lactate (11.94) compared with the group receiving HES130/0.4 (67.94) and controls (146.34) (P !0.05). Conclusions: Signalling levels were lower in pigs subjected to fluid replacement with Ringer’s lactate when compared with the control group. Ringer’s lactate might promote better renal perfusion in the presence of severe hypoperfusion. HISTOLOGICAL EVALUATION OF THE SPLEEN AFTER ACUTE BLEEDING FOLLOWED BY VOLUME REPLACEMENT WITH TWO DIFFERENT PHYSIOLOGICAL SOLUTIONS M. Cabral*, A. Ortiz y, C. Venâncio z, J. Mesquita x, C. N obrega x, A. Silva{, H. Vala x and D. Ferreira *Agrarian Superior School, IPV Viseu, Portugal, yUniversity of Le on, Spain, zIBMC-Porto, xCEETS-IPV Viseu, {REQUIMTE, Porto and CICVULHT, Lisboa, Portugal Introduction: The spleen is important for many haemopoietic and immunological functions, particularly in haemodynamic compensation during haemorrhagic shock, with a crucial role in restoring blood volume in situations of acute haemorrhage. The administration of physiological solutions is of great importance for the correction of circulating volume, avoiding complications due to hypovolaemia. The aim of this study was to evaluate histopathological changes in the spleen associated with volume replacement using two different physiological solutions (hydroxyethyl starch [HES] 130/0.4 and Ringer’s lactate), after acute controlled bleeding, in a pig model. Materials andMethods: Thirty-one large white pigs underwent total intravenous anaesthesia with propofol and remifentanil. A total of 25ml/kg of blood was removed passively over 20 min. Intravascular volume was replaced using Ringer’s lactate at 25 ml/kg (group 1, n 5 13) or HES130/0.4 at 20 ml/kg (group 2, n 5 11). Spleen samples were processed for routine histopathological evaluation. Results: Significant differences were found in lymphoid follicular hyperplasia between the control group and group 1, and between group 1 and group 2, with increased follicular hyperplasia in group 1. Conclusions: Volume replacement with HES130/0.4 may reduce follicular lymphoid hyperplasia when compared with volume replacement with Ringer’s lactate after acute bleeding.