Siavash Ahmadi-Noorbakhsh; Saeed Azizi; Bahram Dalir-Naghadeh; Masoud Maham
Volume 3, Issue 2 , June 2012, , Pages 125-130
Abstract
Oxygen is an essential part of the most important metabolic pathways in aerobic organisms. Oxygen delivery is merely dependent on blood, rendering blood loss a devastating event. Traumatic pre-hospital liver bleeding is a major cause of early trauma deaths in human and animals, with no established therapeutic ...
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Oxygen is an essential part of the most important metabolic pathways in aerobic organisms. Oxygen delivery is merely dependent on blood, rendering blood loss a devastating event. Traumatic pre-hospital liver bleeding is a major cause of early trauma deaths in human and animals, with no established therapeutic method yet. Increasing intra-abdominal pressure (IAP) has been shown to reduce liver bleeding by half. Although reduction of blood loss could be in favor of blood oxygen delivery, however, the complex interaction between increased IAP and respiratory mechanics during severe hemorrhagic shock remained unclear. We used a novel model of liver trauma in 16 rabbits and randomly assigned them to either normotensive abdomen group or increased IAP by fluid infusion (HA) groups (n=8 each). Liver size and the amount of liver injury were evaluated. Various blood oxygenation parameters were recorded. Both groups were identical in terms of the liver size and injury. The HA group had significantly lower shock index. Arterial oxygen capacity and oxygen content were higher in the HA group. No significant statistical difference was seen between groups in terms of abdominal perfusion pressure; alveolar pressure of oxygen; dissolved oxygen in blood plasma; alveolar to arterial oxygen tension gradient; arterial to alveolar oxygen pressure ratio; the ratio between partial pressure of arterial oxygen and fraction of inspired oxygen; and respiratory index. In conclusion, the novel therapeutic method of increasing IAP by fluid infusion in a rabbit model of liver hemorrhage preserved blood oxygenation better than the classic therapeutic method.
Saeed Azizi; Rahim Mohammadi; Keyvan Amini; Roza Fallah; Kiana Karegar
Volume 1, Issue 2 , September 2010, , Pages 107-115
Abstract
Despite promising results observed using silicone rubber chamber, no previous comprehensive work was performed on behavior of the conduit. Present study aimed at further functional, histomorphometrical and immunohistochemical assessment of nerve regeneration in the same animal along a 10-mm rat ...
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Despite promising results observed using silicone rubber chamber, no previous comprehensive work was performed on behavior of the conduit. Present study aimed at further functional, histomorphometrical and immunohistochemical assessment of nerve regeneration in the same animal along a 10-mm rat sciatic nerve gap. Fifty- four male Wistar rats were divided into three experimental groups (n = 18), randomly: Sham-operation (NC), Transected control (TC) and silicone conduit (SIL). In NC group after anesthesia left sciatic nerve was exposed through a gluteal muscle incision and after haemoestasis the muscle was sutured. In TC group left sciatic nerve was exposed the same way and transected proximal to the tibio-peroneal bifurcation leaving a 10-mm gap. In SIL group left sciatic nerve was transected the same way and proximal and distal stumps were each inserted into a silicone tube. Each group was subdivided into three subgroups of six animals each and were studied 4, 8, 12 weeks after surgery. Functional analysis showed significant improvement of nerve function in SIL group than in TC group (P < 0.05). Morphometric indices and immuohistochemistry indicated there were significant differences (P < 0.05) between SIL and TC groups 12 weeks after surgery. Silicone entubulation technique has offered the hope of providing a method for achieving the peripheral nerve regeneration in the least harmful way that is available, easily performed. Using silicone tubes in bridging of nerve defects could be promising because it is inert and does not induce extensive scarring or degeneration after implantation.
