spinal anesthesia

References

spinal anesthesia

pathology

Also known as: Intrathecal anesthesia, saddle block

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July 14, 2026

Quick Summary

Spinal anesthesia, also known as a spinal block, is a type of local anesthesia administered by injecting a local anesthetic agent into the cerebrospinal fluid in the lumbar region of the spine. This procedure numbs a significant area of the body, typically the abdomen, legs, and feet, while allowing the patient to remain conscious.1

A lumbar puncture is the process of aspirating cerebrospinal fluid (CSF) through a needle inserted into the lower back, usually between the third and fourth lumbar vertebrae, into the subarachnoid space of the spinal cord. This procedure is performed to measure CSF pressure, collect a sample for examination, or administer substances like spinal anesthetics.2

Spinal anesthesia is often used for cesarean sections or when delivery is anticipated within a couple of hours. A specific type, the saddle block, targets the inner thighs, buttocks, and perineum. While effective, potential risks include maternal hypotension and a reduced urge to push.1

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birth
Spinal anesthesia
Spinal anesthesia (sometimes called spinal block) is produced when a local anesthetic agent, such as lidocaine or bivucaine, sometimes mixed with a narcotic, is injected into the cerebrospinal fluid in the lumbar region of the spine. This technique allows the woman to be…
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Spinal anesthesia (sometimes called spinal block) is produced when a local anesthetic agent, such as lidocaine or bivucaine, sometimes mixed with a narcotic, is injected into the cerebrospinal fluid in the lumbar region of the spine. This technique allows the woman to be…
Read More

therapeutics
Local drug therapy
Spinal anesthesia and epidural anesthesia, in which a local anesthetic is injected into the subarachnoid or epidural space of the lumbar (lower back) area of the spinal canal, provide pain relief during childbirth or surgery that involves the pelvic area yet lack the problems associated…
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Spinal anesthesia and epidural anesthesia, in which a local anesthetic is injected into the subarachnoid or epidural space of the lumbar (lower back) area of the spinal canal, provide pain relief during childbirth or surgery that involves the pelvic area yet lack the problems associated…
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cardiovascular disease
Neurogenic shock
Thus, spinal anesthesia—injection of an anesthetic into the space surrounding the spinal cord—or severance of the spinal cord results in a fall in blood pressure because of dilation of the blood vessels in the lower portion of the body and a resultant diminution of venous return…
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Thus, spinal anesthesia—injection of an anesthetic into the space surrounding the spinal cord—or severance of the spinal cord results in a fall in blood pressure because of dilation of the blood vessels in the lower portion of the body and a resultant diminution of venous return…
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anesthetic
Local anesthetics
…into the cerebrospinal fluid (spinal or intrathecal anesthesia). In spinal anesthesia, the specific gravity of the local anesthetic solution is appropriately adjusted, and the patient is positioned in such a way that the anesthesia is confined to a particular region of the spinal cord. In both epidural and spinal…
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…into the cerebrospinal fluid (spinal or intrathecal anesthesia). In spinal anesthesia, the specific gravity of the local anesthetic solution is appropriately adjusted, and the patient is positioned in such a way that the anesthesia is confined to a particular region of the spinal cord. In both epidural and spinal…
Read More