Letters to the Editor: Letters & Announcements
To the Editor:
We read with interest the three case reports by Chan et al. (1) regarding persistent fluid leak, confirmed as cerebrospinal fluid (CSF), following combined spinal epidural anesthesia. They discussed the dilemma of management of the leak, exacerbated by the fistulous track left by the indwelling epidural catheter. Recently, we had a similar dilemma in the management of a patient who had an epidural infusion for postoperative pain relief after laparotomy. It was considered impractical to site the epidural before induction, so, after instituting general anesthesia, the epidural space was identified using “loss of resistance to air” technique at the T11/T12 interspace (16-gauge Tuohy needle, left lateral position). When the epidural catheter (Portex, multi-orifice), not prefilled with fluid, was threaded through the needle, clear fluid was seen in it, which could not however be aspirated freely. The catheter was withdrawn to 11 cm at the skin and flushed with normal saline. Free flow of fluid was noticed up and down the catheter when opened to air, therefore, implying that the catheter was within the spinal canal, although the possibility of a dural tap by the catheter was noted.
The postoperative course was uneventful until the second postoperative day, 3 hours after the epidural catheter had been removed. Clear fluid was seen leaking from the epidural puncture site that was initially assumed to be CSF. However, the patient had neither headache nor any neurological signs or symptoms. Examination of the back revealed dependent edema along the length of the back and a normal epidural puncture site. A sample of the leakage fluid was collected and tested with a reagent strip, which was consistent with this fluid being interstitial fluid and not CSF. The leak subsided spontaneously on the fifth postoperative day without any further active management.
We feel situations like this might occur more frequently in future because of increasing use of epidural infusion postoperatively for analgesia in high-risk surgical patients. In a recent audit of epidurals for postoperative pain relief in surgical patients conducted in the hospital, the incidence of fluid leak from epidural puncture site was found to be 10% despite there being no identified dural taps. We did not, however, analyze the composition of the leaking fluid biochemically. This increasing problem of fluid leak from epidural puncture sites needs to be studied in more detail so that the true incidence of fluid leak (CSF or interstitial) can be identified to help plan the logical steps for diagnosis and management of this problem.
Sujesh Bansal, MD, DNB
West Wales General Hospital
Carmarthen, United Kingdom
1. Chan BO, Paech MJ. Persistent cerebrospinal fluid leak: a complication of the combined spinal-epidural technique. Anesth Analg 2004;98:828–30.