6. During spinal anesthesia, all of the following SIGNIFICANTLY influence the distribution of local anesthetic in the cerebrospinal fluid (CSF), EXCEPT?

Answer: Cerebrospinal fluid circulation

By and large, increasing the dose of local anesthetic injected into the CSF will affect the level of spinal anesthesia.  The higher the dose injected the greater the spread.  Baricity in combination with the shape of the spinal column and position of the patient have the most profound effect on the spread of local anesthetic in the CSF.  Cerebrospinal fluid circulation is a slow process and has little effect on the distribution of local anesthetic in the CSF.

Reference:

Greene NM: Distribution of local anesthetic solutions within the subarachnoid space. Anesth Analg 1985; 64: 715-730

Return to this Question    Next Question