Summary
Pol-vesfer resin was injected into
Key wordsAnatomy; epidural space.The epidural space lies between the spinal dura mater internally, and the periosteal and ligamentous lining of the vertebral canal externally. It contains loose fatty connective tissues, arteries and a plexus of veins. The shape of the epidural space, as seen in cross-section, is governed by the shapes of the vertebral canal and dural sac. In the lumbar region the vertebral canal is triangular' with the apex in the dorsal midline. The vertebral canal is unyielding but the dural sac may be displaced inwards when the epidural space is distended by injection of fluid. Although the shape of the lumbar epidural space may have important clinical implications, it has been the subject of only limited investigation.
Materials and methodsLow viscosity polyester resin suitable for preparation of anatomical corrosion casts (Trylon Ltd, Wollaston, Northants, NN9 7QJ), was injected into the epidural space of ten adult cadavers within 12 h of death. The cadavers ranged in age from 37 to 65 yr and had no known vertebral or central nervous system disease or deformity. Between 40 and 60 ml of freshly prepared polyester resin was injected through a 17-gauge Tuohy needle introduced via the second or third lumbar interspace (posterior midline approach), or the sacral hiatus. The appropriate timing of injections after preparation of the polyester resin was
Summary
Analgesia mediated by a direct spinal action of narcotic drugs administered via the epidural route may have considerable advantages over conventional (conduction block) epidural analgesia in labour. The efficacy, mode of action and placental transfer of epidurally administered narcotics in labour has not yet been established. We have compared the systemic absorption, analgesia and other effects on the mothers and transfer of drug to the fetus in primigravidae who received epidural or intramuscular pethidine 100 mg in labour. The superior analgesia following epidural pethidine did not appear to be attributable to a selective spinal action but rather to higher plasma concentrations of pethidine together with a possible weak regional conduction block due to local anaesthetic action of 1 % pethidine solution. Epidural pethidine is not an advantageous method for providing analgesia in labour.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.