Korean J Anesthesiol.  2006 Jun;50(6):642-645. 10.4097/kjae.2006.50.6.642.

The Effect of the Spinal Block Level on the Requirements of Propofol for Sedation

• Shin IW
• Go JE
• Park KE
• Sohn JT
• Chung YK
• Lee HK

• KMID: 1862239
• DOI: http://doi.org/10.4097/kjae.2006.50.6.642

Abstract

BACKGROUND: It has been reported that spinal anesthesia has a sedative effect and so this decreases the hypnotic requirement of intravenous anesthetic. Therefore, we have conducted a prospective randomized study to investigate the effect of the spinal anesthesia level on the hypnotic requirements for conscious sedation.
METHODS
Forty adult patients were scheduled to undergo spinal anesthesia, and they were randomly allocated to one of the two groups. After subarachnoid injection of 0.5% hyperbaric bupivacaine 16 mg, the patients in group 1 and group 2 were maintained in a reversed Trendelenburg position and a Trendelenburg position, respectively. After fifteen minutes, the target controlled infusion of propofol was started for achieving a target concentration of 1 microgram/ml, and the mean BIS for 1 min was checked after an effect site concentration (Ce) of 1 microgram/ml was reached. The target controlled infusion of propofol was restarted at a target concentration (Tc) of 1.5 microgram/ml, and the mean BIS for 1 min was checked after the Ce level of 1.5 microgram/ml was reached.
RESULTS
The mean BIS at 1 microgram/ml Ce was 90.0 +/- 8.5 and 77.8 +/- 10.3 in group 1 and group 2, respectively. The mean BIS at 1.5 g/ml Ce was 73.6 +/- 19.4 and 60.0 +/- 13.1, respectively.
CONCLUSIONS
There was a significant difference in the requirements of propofol for conscious sedation between the below T12 block group and the above T4 block group.

Keyword

bispectral index; hypnosis; propofol; spinal anaesthesia

MeSH Terms

Adult
Anesthesia, Spinal
Bupivacaine
Conscious Sedation
Head-Down Tilt
Humans
Hypnosis
Hypnotics and Sedatives
Propofol*
Prospective Studies
Bupivacaine
Hypnotics and Sedatives
Propofol