POTENTIAL INTRATHECAL LEAKAGE OF SOLUTIONS INJECTED INTO THE EPIDURALSPACE FOLLOWING COMBINED SPINAL EPIDURAL-ANESTHESIA

A combined spinal epidural anaesthetic (CSE), by design, produces a de liberate multicompartment block across a breached dural membrane. Sinc e the lateral holes of the epidural catheter may lie in close proximit y to the dural puncture site, a bolus solution of drug injected via th e epidural catheter has the potential to leak through the dural punctu re into the subarachnoid space. The aim of this study, was to determin e the incidence of intrathecal leak by performing an epidurogram. Fift een patients undergoing surgery with a CSE anaesthetic using a 16 gaug e Tuohy/26 gauge pencil point needle were studied. Within three hours of catheter insertion, 12 ml of contrast (iohexol 300 mg/ml) was injec ted via the epidural catheter under fluoroscopic control with screen r ecording and exposure of lateral and anteroposterior X-ray plates. All films were later reviewed for evidence of intrathecal spread. We did not observe any evidence of intrathecal spread of contrast. However ca ution should be observed during administration of an intraoperative bo lus dose of analgesic agent via a catheter inserted as part of a combi ned spinal epidural anaesthetic technique, particularly with the use o f hydrophilic opiods.