Furthermore, concerns have been raised over inadequate fluid resuscitation with deleterious hemodynamic and organ perfusion effects [18, 19]. Therefore, experimental models to study fluid resuscitation related to traumatic hemorrhage should be clinically relevant, and contemplate timing and sequence of events that take place in urban or military trauma [13, 20]. Also important are research tools capable of providing information about the actual
consequences of different resuscitation strategies on organ perfusion; one useful tool is the microsphere deposition method [21–24]. In a previous study with radioactive microspheres moderate volume resuscitation improved organ perfusion with less bleeding after venous hemorrhage compared to large volume or no volume [25]. In that study, the interventions were not designed SGC-CBP30 datasheet to
Selleckchem GSK2126458 simulate a real trauma scenario, and the resuscitation regimen used was not pressure guided [25]. The objective of this study was to investigate regional organ perfusion acutely following uncontrolled hemorrhage in an animal model that simulates a penetrating vascular injury and accounts for prehospital times in urban trauma. We set forth to determine if hypotensive resuscitation (permissive hypotension) would result in equivalent organ perfusion compared to normotensive resuscitation. Materials and methods The study was approved by the Animal Research and Ethics Committee of the Federal University of Minas Gerais, Belo Horizonte, Vistusertib nmr Brazil, and conducted under stringent animal ethics protocol. Animals Male Wistar rats (250-335 g) were housed in groups of 3 in appropriate cages, and maintained at 25oC on 12-hour light/dark cycles. Animals were acclimated for 2 weeks before the experiment, were fed rat chow (Purina® Ratochow, Caxias, RS,
Brazil) and water ad-libitum. Monitoring procedures Animals were anesthetized with 60 mg/kg of ketamine and 15 mg/kg of xylazine (Rhabifarma Industria Farmaceutica Ltda., Hortolandia, SP, Brazil) by intraperitoneal injection. Additional doses of ketamine and xylazine were administered intravenously, 2.5 mg/kg and 1mg/kg respectively. Operative sites were prepared with 10% povidone iodine solution. A tracheotomy was performed, and a segment of a 14 G intravenous catheter (Smiths Medical do Brasil, Leukocyte receptor tyrosine kinase Sao Paulo, SP, Brazil), approximately 2.5 cm in length, was inserted into the trachea. The left internal jugular vein, the right carotid artery, and the right femoral artery were cannulated with polyethylene tubing (PE 50; Clay Adams, Sparks, MD) prefilled with heparinized saline solution (Parinex® Hipolabor, Sabara, MG, Brazil). Mean arterial blood pressure (MAP) and heart rate (HR) were continuously monitored with a Biopac (Biopac Systems Inc., Goleta, CA) connected to the right femoral artery after five minutes stabilisation period.