Lumbar epidurography with multi-orifice and single orifice epidural catheters.

The spread of iohexol in the epidural space was studied using two types of epidural catheter. Twenty pre-menopausal women undergoing hysterectomy received lumbar epidural analgesia via either multi-orifice or single orifice catheters. Twenty-four hours after surgery, iohexol was injected before catheter removal with the patient lying supine. Whereas there was no significant difference in the total number of vertebral segments covered by dye or the total number of segments reached above or below the level of epidural insertion, spread was more even to the right and left of midline using the single orifice catheters. Sacral spread of dye was only observed when a single orifice catheter was used. Epidural catheter design affects the distribution of solutions in the epidural space, with single orifice epidural catheters producing more even distribution of dye with sacral extension.