ORIGINAL: Meniscus Sign: A Test for the Confirmation of Correct Placement of Epidural Catheter

West Afr J Med. 2021 April; 38(4): 374-379 PMID: 33903091

Abstract

Background: Localization of epidural space has no clear-cut end point like during subarachnoid block, making it an enigma to the anaesthetist. Confirmation of correct placement of the catheter is desirable in order to prevent failure, high or total spinal when large amount of local anaesthetic agent is inadvertently injected in the intrathecal space, subdural block and lastly local anaesthesia systemic toxicity. This study evaluated the use of meniscus sign to confirm correct placement of epidural catheter.

Materials and method: A total of 80 patient's scheduled for epidural anaesthesia were recruited into this prospective observational study. The epidural space was located using the loss of resistance to air (LORA) technique. An epidural catheter was inserted gradually through the Tuohy needle, with its removal, 4cm of catheter left in the space and a test dose of 2% lidocaine with adrenaline was instilled. The presence of meniscus sign on the catheter was used to confirm correct placement. The number of correctly placed epidural catheters, intravascular or peri-dura placements were all noted.

Result: Of the 80 patients, meniscus sign confirmed correct epidural catheter placement in 74 of them"(92.5% success)". The study showed 100% success for both sensitivity and specificity when the meniscus sign was used for locating epidural placement.

Conclusion: The meniscus sign is a reliable indicator of correct epidural catheter placement, with high sensitivity and specificity.