Intrathecal catheterizing

We used inhaled anesthesia. The rats were inhaled 2.5% isoflurane for induction before the surgery and 2% isoflurane for maintenance during the surgery. Intrathecal catheterizing was performed on the special surgical table for rats after anesthesia. The back skin of rats were cleaned and disinfected with iodine gently. We located the L6 by the iliac crest of rats, which made us easy to locate L3-4 interspace. Then, longitudinal skin incision was done to expose muscle and fascia. The inter-spine space was fully exposed by carefully removing redundant lamina and spines. After clearance of L3-4 interspace, we breakthroughed yellow ligament with a fine epidural catheter slowly and gently, then placed it into the cephalic side by 2 cm. The success of subarachnoid cava was confirmed when we saw colorless cerebrospinal fluid flowing out of the catheter. The other end of the catheter was led out of the back neck of the rats subcutaneously. We fixed the tube on the head of rats to prevent it being scratched off by the rats. In addition, 15,000 units of penicillin were injected intraperitoneally to prevent postoperative infection effectively. After 48 h of surgery, the bilateral hind limbs and tail movements of rats were observed to confirm there is no occurrence of spinal nerve injury.