Hyperbaric
Local anesthetic solution with specific gravity greater than cerebrospinal fluid, causing gravitational spread in spinal anesthesia.
Full Definition
Hyperbaric local anesthetic solutions have a specific gravity greater than that of cerebrospinal fluid (CSF), typically achieved by adding dextrose to the anesthetic agent. When injected intrathecally, hyperbaric solutions tend to settle in the most dependent parts of the subarachnoid space due to gravitational forces. This property allows anesthesiologists to direct the spread of spinal anesthesia by positioning the patient appropriately during and after injection. In obstetric anesthesia, hyperbaric bupivacaine is commonly used for cesarean deliveries, providing predictable distribution and adequate surgical anesthesia. Patient positioning during the first 15-30 minutes after injection significantly influences the final distribution of the block.
Usage
Usage note: Specify concentration and positioning when documenting hyperbaric solutions.
In Context
- "Hyperbaric bupivacaine 0.75% was used to ensure adequate cephalad spread for cesarean anesthesia." — Spinal anesthesia documentation
- "The patient was positioned supine immediately after hyperbaric spinal injection to promote appropriate block height." — Anesthetic technique note