Identification and confirmation of the epidural space in infants and children

I read the comprehensive review on identification and confirmation of the epidural space by Dr. Teng WN1 with a great interest. I would like to provide additional information on the technique I have been using in pediatric epidural analgesia for more than a quarter of a century. Robin Cox also quotes this technique in the special article. This technique is one of the methods that modify the loss of resistance technique. A sterile intravenous micro-drip infusion set, prepared with saline as for an intravenous infusion, is added to the standard epidural tray. The tip of the epidural needle is inserted into inter spinous ligament, the stiletto is removed and the distal end of the infusion set is connected to the needle hub. The micro-drip chamber is kept about 1 m above the puncture site. The clamp of the infusion set is opened fully; no dripping should be observed if the tip of the needle is in inter spinous ligament. An assistant observes the drip chamber while the anesthesiologist advances the needle slowly and carefully. At the first sight of dripping (an objective sign of loss of resistance), the anesthesiologist is notified immediately. He stops advancing the needle, confirms free flow of fluid in the drip chamber, and closes the clamp. Usually, movement of a tiny air bubble at the hub of the epidural needle towards the epidural space can be observed by the anesthesiologist.