@article{NguyenDuongTranetal.2012,
  author    = {Nguyen, Nhu Huynh and Duong, Minh Tuan and Tran, Thanh Ngoc and Pham, Phu Tinh and Grottke, O. and Tolba, R. and Staat, Manfred},
  title     = {Influence of a freeze-thaw cycle on the stress-stretch curves of tissues of porcine abdominal organs},
  series = {Journal of Biomechanics},
  volume    = {45},
  journal   = {Journal of Biomechanics},
  number    = {14},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-2380},
  doi       = {10.1016/j.jbiomech.2012.07.008},
  pages     = {2382 -- 2386},
  year      = {2012},
  abstract  = {The paper investigates both fresh porcine spleen and liver and the possible decomposition of these organs under a freeze-thaw cycle. The effect of tissue preservation condition is an important factor which should be taken into account for protracted biomechanical tests. In this work, tension tests were conducted for a large number of tissue specimens from twenty pigs divided into two groups of 10. Concretely, the first group was tested in fresh state; the other one was tested after a freeze-thaw cycle which simulates the conservation conditions before biomechanical experiments. A modified Fung model for isotropic behavior was adopted for the curve fitting of each kind of tissues. Experimental results show strong effects of the realistic freeze-thaw cycle on the capsule of elastin-rich spleen but negligible effects on the liver which virtually contains no elastin. This different behavior could be explained by the autolysis of elastin by elastolytic enzymes during the warmer period after thawing. Realistic biomechanical properties of elastin-rich organs can only be expected if really fresh tissue is tested. The observations are supported by tests of intestines.},
  language  = {en}
}
@article{GrottkeBraunschweigPhilippenetal.2010,
  author    = {Grottke, O. and Braunschweig, T. and Philippen, B. and Gatzweiler, Karl-Heinz and Gronloh, N. and Staat, Manfred and Rossaint, R. and Tolba, R.},
  title     = {A new model for blunt liver injuries in the swine},
  series = {European Surgical Research},
  volume    = {44},
  journal   = {European Surgical Research},
  number    = {2},
  publisher = {Karger},
  address   = {Basel},
  issn      = {1421-9921},
  doi       = {10.1159/000265053},
  pages     = {65 -- 73},
  year      = {2010},
  abstract  = {Background: To elaborate the impact of new haemostatic agents we developed an instrument for the pressure-controlled induction of blunt liver injuries in a porcine animal model. Materials and Methods: A dilutional coagulopathy of 80\% of animal blood volume was induced in 9 anaesthetized pigs. Animals were randomly assigned to be injured with a force of 112 Newton (N) (n = 1), 224 ± 19 N (n = 4) or 355 ± 35 N (n = 4). The impact of injury was measured by blood loss, survival time and coagulation parameters. Liver histology was obtained to evaluate the degree of liver injury. Results: The profound haemodilution resulted in a significant alteration of all coagulation parameters. After inflicting the injury with 355 ± 35 N, both the survival time (30 ± 9 min; p = 0.006) and blood loss (68 ± 16 ml min-1, p = 0.002) were significantly different as compared to injuries with 224 ± 19 N (survival time: 76 ± 20 min, blood loss: 23 ± 4 ml min-1). In contrast, an injury with 112 N led to an insignificant blood loss of only 239 ml. Conclusion: We developed a pressure-controlled clamp that allows for the induction of blunt liver traumas with highly reproducible injuries with a positive correlation with blood loss and survival.},
  language  = {en}
}