Clinical Research Directory

A Non Invasive Confirmatory Sign for Correct Epidural Catheter Placement During Normal Vaginal Delivery

Epidural anesthesia for pain control during normal vaginal delivery is a blind maneuver and so we need a confirmatory sign for being in the correct epidural space. Loss of resistance sign using air may guide us wrongly as it may occur if we entered into the paravertebral muscles or cavities in the interspinal ligaments. So, additional confirmatory sign beside loss of resistance sign by air is strongly needed. We noticed that after occurence of loss of resistance sign by air and insertion of the epidural catheter a dew was formed on the internal sides of the epidural catheter after aspiration to be sure that there are no blood or cerebrospinal fluid in the catheter. This dew formation (Ramy sign) is characteristic for air in the epidural space when transferred from the warm epidural space (temperature about 38-39 celsius degree) to the colder aspect of the catheter outside the patient which nearly has the same operating room temperature (22 celsius degree). This sign may be associated with correct placement and good function of the epidural catheter.