What is the term for the penetration of anesthetic into the subarachnoid space?

The term for the penetration of anesthetic into the subarachnoid space is indeed a spinal block. This technique involves the injection of a local anesthetic directly into the cerebrospinal fluid (CSF), which envelops the spinal cord within the subarachnoid space. By doing so, it allows for rapid and effective anesthesia for various surgical or medical procedures, particularly those involving the lower body.

The specific nature of a spinal block distinguishes it from other forms of anesthesia. For instance, an epidural block involves administering anesthetic agents into the epidural space, which is outside the dura mater and does not penetrate into the CSF, making its anesthetic effect and onset differ significantly from that of a spinal block. Frequent block and neuroleptic block do not refer to this specific technique and focus on entirely different contexts in anesthetic and psychiatric treatment.

Thus, understanding that a spinal block directly targets the subarachnoid space provides clarity on its use in clinical practice and highlights its importance in delivering localized anesthesia effectively.