Final answer:
Possible complications of high dose bupivacaine injection into the subarachnoid space include spinal headache, arachnoiditis, and spinal cord injury.
Step-by-step explanation:
When bupivacaine is injected into the subarachnoid space, several complications can arise. One possible complication is a condition called spinal headache, which is characterized by severe head and neck pain. Another potential complication is a condition known as arachnoiditis, which is inflammation of the arachnoid membrane. Finally, high dose bupivacaine injection can lead to spinal cord injury, resulting in symptoms such as numbness, weakness, and difficulty walking.