Rosana Celestina Morandin

Importance Of Anesthesia For The Genesis Of Neurogenic Pulmonary Edema In Spinal Cord Injury.

There are reports describing both provocation and inhibition of neurogenic pulmonary edema by anesthetic drugs. Therefore, we compared the effect of two types of anesthesia on the formation of neurogenic pulmonary edema in rats with balloon-induced acute spinal cord injury. Animals with sham procedure (group 1) were anesthesized by intraperitoneal sodium pentobarbital. In the experimental groups, rats were submitted to acute spinal cord lesion by insufflations of a balloon in the epidural space at T8 for 1 min (group 3 under i.p. sodium pentobarbital and group 2 under i.p. xylazine-ketamine anesthesia). In rats with pentobarbital anesthesia, systolic blood pressure doubled the baseline value during compression, whereas this effect was less pronounced in the ketamine-xylazine group. The pulmonary index (100 x wet lung weight/body weight) was 0.395 (+/-0.018) in sham-operated rats, rose to 0.499 (+/-0.060) in group 2, and was maximum under pentobarbital anesthesia (0.639+/-0.14; p=0.0018). Histologic examination of the spinal cord showed parenchymal ruptures and acute hemorrhage. Comparison of the pulmonary index with histologic slides of lung parenchyma revealed that relevant intra-alveolar edema occurred only for index values above 0.55. On electron microscopy, endothelial alterations, and damage of the alveolar lining cells were found. Our study indicates that neurogenic pulmonary edema caused by spinal cord injury is less pronounced in rats under xylazine-ketamine anesthesia, when compared with pentobarbital.

Hemodynamic parameters and neurogenic pulmonary edema following spinal cord injury: an experimental model

Neurogenic pulmonary edema is a serious and always life-threatening complication following several lesions of the central nervous system. We report an experiment with 58 Wistar-Hanover adult male rats. Two groups were formed: control (n=4) and experimental (n=54). The experimental group sustained acute midthoracic spinal cord injury by Fogartys balloon-compression technique containing 20 microL of saline for 5, 15, 30 or 60 seconds. The rats were anesthetized by intraperitoneal (i.p.) sodium pentobarbital (s.p.) 60 mg/Kg. The quantitative neurological outcome was presented at 4, 24 and 48 hours from compression to characterize the injury graduation in different groups. Poor outcome occurred with 60 seconds of compression. Six animals died suddenly with pulmonary edema. Using the procedure to investigate the pulmonary edema during 60 seconds of compression, followed by decompression and time-course of 60 seconds, 20 rats were randomly assigned to one of the following groups: control (1, n=4, anesthetized by i.p. s.p., 60 mg/Kg but without compression) and experimental (2, n=7, anesthetized by i.p. xylazine 10 mg/Kg and ketamine 75 mg/Kg) and (3, n=9, anesthetized by i.p. s.p., 60 mg/Kg). The pulmonary index (100 x wet lung weight/body weight) was 0.395 +/- 0.018 in control group, rose to 0.499 +/- 0.060 in group 2, and was 0.639 +/- 0.14 in group 3. Histologic examination of the spinal cord showed parenchymal ruptures and acute hemorrhage. Comparison of the pulmonary index with morphometric evaluation of edema fluid-filled alveoli by light microscopy showed that relevant intra-alveolar edema occurred only for index values above 0.55. The results suggest that the pulmonary edema induced by spinal compression is of neurogenic nature and that the type of anesthesia used might be important for the genesis of lung edema.

Total hepatic ischemia and reperfusion after state controlled hemorrhagic shock, with used of different solutions: effects of neutrophils sequestration in kidney of rats

Purpose: To evaluate and compare neutrophils sequestration in the renal cortex of rats, result of total hepatic ischemia and reperfusion after controlled hemorrhagic shock, with use of different electrolytic solutions. Methods: Used 18 rats Wistar, males, adult, divided into three groups as the solution used to reanimation: Group PSS: physiologic saline solution; Group HSS: hypertonic saline hypertonic (7,5%) followed by lactated ringer’s solution; Group LRS: lactated ringer’s solution. All the animals were submitted to the bleeding controlled until mean arterial pressure (MAP) 40 mmHg, for 20 minutes. Performed volemic replacement until PAM=80 mmHg with the solution according the studied group, followed by laparotomy and Pringle’s Maneuver for 15 minutes. The animals were accompanied until for two hours. To statistical comparisons between mean of neutrophils sequestration, in interstitium of the renal cortex, were made the tests One-way ANOVA and covariance analysis, adjusting itself for time of supervened. The hemodynamic parameters evaluated were: MAP, heat rate, cardiac index, vascular resistance system index. The analyzed metabolic variables were: pH, bicarbonate, base deficit and lactato, besides electrolytes. Results: The mean values of supervened, in minutes, for group were: Group PSS 79,0±12,0; Group LRS 97,0±11,0; Group HSS 67,0±10. The mean values of neutrophils/field in the renal cortex were: Group PSS 0,55±0,68; Group LRS 1,68±0,53; Group HSS 1,33±0,43. When adjusted for time of supervened: Group PSS 0,55; Group LRS 1,62; Group HSS 1,39. There was statistically significant difference in neutrophils sequestration, between Group PSS regarding the others groups, using itself or not the adjustment by time of supervened (p=0,016 and p=0,0128). Conclusion: Both critical situations in this model, controlled hemorrhagic shock followed by Pringle’s maneuver, promoted neutrophils sequestration in the interstitium renal of rat, and the physiologic saline solution demonstrated minor mean, differentiating statistically of the others solutionsPURPOSE To evaluate and compare neutrophils sequestration in the renal cortex of rats, result of total hepatic ischemia and reperfusion after controlled hemorrhagic shock, with use of different electrolytic solutions. METHODS Used 18 rats Wistar, males, adult, divided into three groups as the solution used to reanimation: Group PSS: physiologic saline solution; Group HSS: hypertonic saline hypertonic (7.5%) followed by lactated ringers solution; Group LRS: lactated ringers solution. All the animals were submitted to the bleeding controlled until mean arterial pressure (MAP) 40 mmHg, for 20 minutes. Performed volemic replacement until PAM=80 mmHg with the solution according the studied group, followed by laparotomy and Pringles Maneuver for 15 minutes. The animals were accompanied until for two hours. To statistical comparisons between mean of neutrophils sequestration, in interstitium of the renal cortex, were made the tests One-way ANOVA and covariance analysis, adjusting itself for time of supervened. The hemodynamic parameters evaluated were: MAP, heat rate, cardiac index, vascular resistance system index. The analyzed metabolic variables were: pH, bicarbonate, base deficit and lactato, besides electrolytes. RESULTS The mean values of supervened, in minutes, for group were: Group PSS 79.0+/-12.0; Group LRS 97.0+/-11.0; Group HSS 67.0+/-10. The mean values of neutrophils/field in the renal cortex were: Group PSS 0.55+/-0.68; Group LRS 1.68+/-0.53; Group HSS 1.33+/-0.43. When adjusted for time of supervened: Group PSS 0.55; Group LRS 1.62; Group HSS 1.39. There was statistically significant difference in neutrophils sequestration, between Group PSS regarding the others groups, using itself or not the adjustment by time of supervened (p=0.016 and p=0.0128). CONCLUSION Both critical situations in this model, controlled hemorrhagic shock followed by Pringles maneuver, promoted neutrophils sequestration in the interstitium renal of rat, and the physiologic saline solution demonstrated minor mean, differentiating statistically of the others solutions.

Tratamento do trauma duodenal complexo: comparação entre sutura simples e sutura associada à exclusão pilórica e gastrojejunostomia em cães

PURPOSE The goal of this study is to compare the results of two different procedures to complex duodenal lesion (grade III), in an animal model. METHODS Twenty-four mongrel dogs, weighting 10 to 15 kg, were distributed in 4 groups of 6 animals each. All animals were submitted to a complex duodenal lesion (grade III), with a 50% loss of its circumference. All animals were treated with a longitudinal repair, resulting a significant narrowing of the duodenal lumen. Groups A and C animals were submitted solely to repair while groups B and D, also underwent pyloric exclusion and gastrojejunostomy as a protection method. Groups A and B animals were sacrificed at day 7 post op, while groups C and D were sacrificed at day 14. The following parameters were studied: weight-loss, degree of duodenal stenosis, operative site, vomiting, anastomotic leak, intra-abdominal abscess formation and death. RESULTS The results obtained with simple duodenal repair were superior to pyloric exclusion and gastrojejunostomy in that the animals lost less weight and vomited less. It was also a simpler and less traumatic procedure. There were no differences in duodenal stenosis, leak, intra-abdominal abscess incidence or death between the two treatment groups. CONCLUSION Duodenal suture associated to pyloric exclusion and gastrojejunostomy resulted more weight-loss and more vomiting incidence; the healing process of the duodenal suture line were similar between the two treatments; both treatments resulted similar increase in the duodenal stenosis degree; there were no cases of suture dehiscence, anastomotic leak, intra-abdominal abscess or death related to the kind of treatment; all animals submitted to pyloric occlusion had it intact at the time of necropsis.PURPOSE: The goal of this study is to compare the results of two different procedures to complex duodenal lesion (grade III), in an animal model. METHODS: Twenty-four mongrel dogs, weighting 10 to 15 kg, were distributed in 4 groups of 6 animals each. All animals were submitted to a complex duodenal lesion (grade III), with a 50% loss of its circumference. All animals were treated with a longitudinal repair, resulting a significant narrowing of the duodenal lumen. Groups A and C animals were submitted solely to repair while groups B and D, also underwent pyloric exclusion and gastrojejunostomy as a protection method. Groups A and B animals were sacrificed at day 7 post op, while groups C and D were sacrificed at day 14. The following parameters were studied: weight-loss, degree of duodenal stenosis, operative site, vomiting, anastomotic leak, intra-abdominal abscess formation and death. RESULTS: The results obtained with simple duodenal repair were superior to pyloric exclusion and gastrojejunostomy in that the animals lost less weight and vomited less. It was also a simpler and less traumatic procedure. There were no differences in duodenal stenosis, leak, intra-abdominal abscess incidence or death between the two treatment groups. CONCLUSION: Duodenal suture associated to pyloric exclusion and gastrojejunostomy resulted more weight-loss and more vomiting incidence; the healing process of the duodenal suture line were similar between the two treatments; both treatments resulted similar increase in the duodenal stenosis degree; there were no cases of suture dehiscence, anastomotic leak, intra-abdominal abscess or death related to the kind of treatment; all animals submitted to pyloric occlusion had it intact at the time of necropsis.

Isquemia e reperfusão hepática total associada ao estado de choque hemorrágico controlado: efeitos no seqüestro de neutrófilos no fígado do rato

BACKGROUND:The purpose of this experimental study was to evaluate the effects of total hepatic ischemia and reperfusion on the accumulation of neutrophils in the liver of rats, under normal conditions and in rats submitted to controlled hemorrhagic shock . METHODS: Thirty two adult male Wistar rats, were divided into four groups: the Control group, was submitted to the standard procedures for a period of 60 min of observation; Shock group, was submitted to controlled hemorrhagic shock (mean arterial blood pressure = 40 mmHg, 20 min) followed by volume resuscitation (lactated Ringers solution + blood, 3:1) and reperfusion for 60 min; Pringle group, was submitted to total hepatic ischemia for 15 min and reperfusion for 60 min; The Total group, was submitted to controlled hemorrhagic shock for 15 min followed by volume resuscitation (lactated Ringers solution + blood, 3:1), total hepatic ischemia for 15 min and reperfusion for 60 min. Measurements of serum lactate and base excess were used to characterize the hemorrhagic shock state with low tissue perfusion. The counting of neutrophils on the liver tissue was performed after the euthanasia of animals. RESULTS: Values for the counting of neutrophils on the liver indicate that, the animals from Pringle group differed from Shock and Total groups (Control 10.30±3.20, Shock 13.94±2.84, Pringle 7.00±3.40, Total 12.45±3.65) but did not differ from Control group. CONCLUSIONS: Rats submitted to controlled hemorrhagic shock state associated to total hepatic ischemia for 15 minutes, followed by 60 minutes of reperfusion, did not present significant neutrophils accumulation on liver tissue.

Fatores de risco no tratamento de lesões do ceco com sutura primária em ratos

Purpose: Analyze the results of primary suture in the treatment of cecum traumatic injuries in rats, after the exposure to increasing time intervals between the trauma and the surgery and with different peritonitis degrees. Methods: In a randomized double-blinded study, 96 Wistar male rats, weight ranging between 200 and 250 grams, underwent laparotomy, in which a 5-milimiter-diameter-injury in the contramesenteric edge of the cecum was performed. In 12 animals of the control-group a prompt primary suture was executed, with total and separated stitches, with 7.0 polypropylene thread. In the other groups, with 12 animals each, a laparotomy for repair of the injury was executed after intervals of 30 minutes, 1, 2, 4, 6, 9 and 12 hours. At the time of injury repair, one of its edges was ressected and sent for anatomopathological examination. A daily control after the surgery was done, observing the presence of complications, specially dehiscence of the suture, and the euthanasia of the animals were done in the 1st, 4th, 7th and 14th day after the surgery. Necropsy was executed in all animals, observing the macroscopic and microscopic findings in the area of suture. Results: There was no association between the delay for surgical treatment of the injury and peritonitis degrees. The mortality in the 14 animals with diffuse peritonitis was 100%. Global mortality was 25% (24 animals), and 6 animals (25%) died before treatment. None of the animals treated that evolved to death had complications related to the suture of the injury. These early deaths were due to peritonitis and sepsis. Among the 72 surviving rats, there was dehiscence of the suture in 9 animals (12.5%). This complication was statistically significant greater in animals operated on after the sixth hour following the trauma. The incidence of dehiscence was also greater in the rats presenting more intense fecal contamination. Intensity of the peritonitis at the moment of suture observed in histological examination had no association with the occurrence of complications of the primary suture. Conclusion: The primary suture as a risky procedure to treat rats, after an interval superior to six hours after the trauma or in the period of intense contamination of the cavity by feces.

Recruitment of neutrophils across the blood-brain barrier: the role of posttraumatic hepatic ischemia

PURPOSE: To study the effects of total hepatic ischemia, and reperfusion on the accumulation of neutrophils in the brain of rats submitted to normovolemic conditions as well as to controlled hemorrhagic shock state. METHODS: Thirty two adult male Wistar rats, were divided into four groups: the Control group, was submitted to the standard procedures for a period of 60 min of observation; Shock group, was submitted to controlled hemorrhagic shock (mean arterial blood pressure=40mmHg, 20min) followed by volemic resuscitation (lactated Ringers solution + blood, 3:1) and reperfusion for 60min; Pringle group, was submitted to total hepatic ischemia for 15min and reperfusion for 60min. The total group was submitted to controlled hemorrhagic shock for 20min followed by volemic resuscitation (lactated Ringers solution + blood, 3:1), total hepatic ischemia for 15min and reperfusion for 60min. Measurements of serum lactate and base excess were used to characterize the hemorrhagic shock state with low tissue perfusion. The counting of neutrophils on the brain was performed after the euthanasia of animals. RESULTS: The values for the counting of neutrophils on the brain indicate that did not occur difference among studied groups (p=0.196) (Control 0.12± 0.11, Shock 0.12± 0.13, Pringle 0.02± 0.04, Total 0.14± 0.16). CONCLUSION: Hemorrhagic shock associated to total hepatic ischemia for 15 minutes, followed by 60 minutes of reperfusion, did not causes significant neutrophils accumulation in the brain of rats.