Abstract:ObjectiveTo establish an upper thoracic epidural anesthesia model in rats. MethodsA total of 120 rats were used in this study. Rats were fixed in a prone position, and an epidural catheter was implanted into the spinal epidural space through the T4-5 joint in cephalad direction. At 48 hours after catheterization, 100 μL/kg methylene blue was injected into the epidural cavity in rats to evaluate whether the catheterization was successful or not, and to identify the location and distribution of the drug solution. ResultsThe thoracic epidural anesthesia model was successfully performed in 85.8% of the rats. The infection rate of the epidural cavity was 0, and the rate of catheter prolapse was 5% after 48 hours. ConclusionsT4-5 cephalad catheterization is feasible to provide a stable upper thoracic epidural anesthesia model in rats, with apparent advantages such as mild traumatic injury, good stability, high success rate, lower cost, and less time consuming.