Faculty Collaboration Database

Lumbosacral cerebrospinal fluid volume is the primary determinant of sensory block extent and duration during spinal anesthesia. Anesthesiology 1998 Jul;89(1):24-9

Date

07/17/1998

Pubmed ID

9667290

DOI

10.1097/00000542-199807000-00007

Scopus ID

2-s2.0-0031821322 (requires institutional sign-in at Scopus site)   206 Citations

Abstract

UNLABELLED: BACKGROUND. Injection of local anesthetic into cerebrospinal fluid (CSF) produces anesthesia of unpredictable extent and duration. Although many factors have been identified that affect the extent of spinal anesthesia, correlations are relatively poor and the extent of spread remains unpredictable. This study was designed to determine whether variability in the volume of lumbosacral CSF among individuals is a contributing factor in the variability of spinal anesthesia.

METHODS: Spinal anesthesia was administered to 10 healthy volunteers with 50 mg lidocaine in 7.5% dextrose. The technique was standardized to minimize variability in factors known to affect the distribution of spinal anesthesia. The extent of sensory anesthesia was assessed by pin-prick and by transcutaneous electrical stimulation. Motor blockade was assessed in the quadriceps and gastrocnemius muscles by force dynamometry. Duration of anesthesia was assessed by pinprick, transcutaneous electrical stimulation, and duration of motor blockade. Lumbosacral CSF volumes were calculated from low thoracic, lumbar, and sacral axial magnetic resonance images obtained at 8-mm increments. Volumes of CSF were correlated with measures of extent and duration of spinal anesthesia using the Kendall rank correlation test.

RESULTS: Lumbosacral CSF volumes ranged from 42.7 to 81.1 ml. Volumes of CSF correlated with pin-prick assessments of peak sensory block height (P = 0.02) and duration of surgical anesthesia (as assessed by the duration of tolerance to transcutaneous electrical stimulation at the ankle (P < 0.05).

CONCLUSIONS: Variability in lumbosacral CSF volume is the most important factor identified to date that contributes to the variability in the spread of spinal sensory anesthesia.

Author List

Carpenter RL, Hogan QH, Liu SS, Crane B, Moore J

Author

Quinn H. Hogan MD Professor in the Anesthesiology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adult
Anesthesia, Spinal
Cerebrospinal Fluid
Cerebrospinal Fluid Pressure
Female
Genetic Variation
Humans
Lumbosacral Region
Male