ObjectiveTo explore the effectiveness and safety of a new temporary intravascular shunt (TIVS) device for limb injury in dogs.MethodsEighteen adult beagle dogs, male or female, weighing (20±2) kg, were taken for experiment. A semi-amputated limb model was made by circular amputating the knee joint of one hindlimb, which retained only skin, femoral artery, femoral vein, femoral nerve, and femur. Then the femoral artery was clamped for 2 hours in all animals, resulting in the ischemic environment of the distal limbs. The animals were randomly divided into 3 groups (n=6). In group A, the bypass was started by using a new TIVS device and replenishing saline through the infusion port; In group B, after intravenous injection of heparin sodium solution, the bypass was started by using a new TIVS device and replenishing 3% heparin sodium solution through the infusion port; In group C, the bypass was started by using the self-made bypass tube. The bypass was end after 12 hours. The general vital signs (body temperature, heart rate, blood pressure) before and after bypass were measured, and the time required for the insertion of the bypass tube, the patency during the bypass, shedding, and thrombosis were recorded. Routine blood test and blood coagulation indicators [white blood cell (WBC), red blood cell (RBC), platelet (PLT), hemoglobin (HGB), activated partial thromboplastin time (APTT), fibrinogen (Fib)] and biochemical indicators [lactic dehydrogenase (LDH) and creatine kinase (CK)] were recorded before bypass and after 3, 6, 9, and 12 hours of bypass, respectively. The gastrocnemius muscles on the surgical side before and after bypass were harvested and the muscle necrosis, the wet-to-dry weight ratio, and the content of malondialdehyde (MDA) and myeloperoxidase (MPO) were measured. In addition, the gastrocnemius muscle and femoral artery were observed after bypass by HE staining.ResultsThere was no significant difference in body temperature, heart rate, and blood pressure between groups before and after bypass (P>0.05). Compared with groups A and B, the time required for the insertion of the bypass tube in group C was significantly longer (P<0.05), and the number of thrombus in the bypass tube, the blockage time significantly increased (P<0.05). Shedding and sliding of bypass tube occurred in 3 cases of group C, but no shedding or sliding of bypass tube occurred in groups A and B; there was no significant difference in the incidence of shedding between groups (P=1.000). There was no significant difference (P>0.05) in routine blood test, blood coagulation indicators, LDH, CK, MPO, MDA, and wet-to-dry weight ratio between groups before bypass. After bypass, the routine blood test and blood coagulation indicators of the 3 groups did not change significantly, and the differences between groups was not significant (P>0.05); LDH and CK gradually increased (P<0.05), and group C significantly higher than groups A and B at 12 hours (P<0.05). After bypass, thrombosis was seen in the bypass tube, the distal gastrocnemius muscle necrosis occurred in group C, and the femoral artery injury was slightly heavier than that in groups A and B.ConclusionThe new TIVS device is safe and effective and has the advantages of convenient implantation, lower thrombosis rate, and less limb ischemia-reperfusion injury.
Severe extremity injury results from high-energy trauma and causes extensive damage to multiple tissues. Such injuries directly threaten both limb viability and patient survival and remains a major challenge in trauma orthopaedics. The cornerstone of treatment is based on comprehensive assessment by a multidisciplinary team to guide evidence-based decisions on limb salvage. In repair and reconstruction strategies, the timing of soft-tissue coverage plays a critical role. Delayed primary flap coverage, performed 3-7 days after injury, has become the preferred approach. After repeated debridement to ensure a clean wound bed, this strategy improves flap survival and reduces infection risk. Fracture fixation requires dynamic decision-making. External fixators provide damage control and temporary stabilization and allow soft tissues to recover. Once conditions permit, conversion to internal fixation, such as intramedullary nails or plates to achieve stable fixation. Complex cases with severe contamination or infection require staged management. After thorough early debridement, local antibiotic delivery using antibiotic-loaded bone cement, such as vancomycin cement, can be applied. This is often combined with negative-pressure wound therapy, and external fixation may serve as definitive treatment. Large segmental bone defects can be managed using the induced membrane technique or bone transport. In addition, emerging strategies such as recombinant Staphylococcus aureus vaccines for infection prevention and three-dimensional-printed personalised implants for bone reconstruction show promising clinical potential.
