Interaction between baricity (glucose concentration) and other factors influencing intrathecal drug spread

• Published in: British journal of anaesthesia : BJA 1994-12, Vol.73 (6), p.744-746
• Main Authors: SANDERSON, P., READ, J., LITTLEWOOD, D.G., MCKEOWN, D., WILDSMITH, J.A.W.
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Anaesthetic techniques; Anaesthetic techniques, subarachnoid; Anaesthetics local; Anaesthetics local, bupivacaine; Anesthesia, Endotracheal; Anesthetics. Neuromuscular blocking agents; baricity; Biological and medical sciences; bupivacaine; Bupivacaine - administration & dosage; Bupivacaine - chemistry; Bupivacaine - metabolism; Bupivacaine - pharmacokinetics; Dose-Response Relationship, Drug; Drug Carriers; Drug Interactions; Female; Glucose - administration & dosage; Glucose - pharmacokinetics; Humans; Male; Medical sciences; Middle Aged; Nerve Block; Neuropharmacology; Pharmacology. Drug treatments; Physics; Physics, baricity; Spinal Puncture; subarachnoid; Time Factors
• ISSN: 0007-0912; 1471-6771
• DOI: 10.1093/bja/73.6.744

The effects of intrathecal injection of 0.5% bupivacaine in solutions containing various concentrations of glucose have been studied in four groups of 20 patients. When solutions containing 0.8% glucose were injected at the L3–4 interspace the median maximum extent of block was higher, and the range of blocks wider, with the 8% solution. All patients receiving 0.8% glucose had blocks between the T5 and T10 dermatomes, confirming previous work on the benefits of this concentration of glucose. In the two other groups 0.5% bupivacaine containing 0 or 0.8% glucose was injected at the L2–3 interspace. In both groups of patients a wider range of blocks, with a median maximum extent that was higher, was produced. These results demonstrate how glucose concentration may be used to influence the spread of intrathecal solutions and how other factors can obscure the effect of glucose concentration.