A Kinked Epidural Needle Tip Preventing Placement of an Epidural Catheter.

Abstract

186 www.anesthesia-analgesia.org September 15, 2017 • Volume 9 • Number 6 To the Editor Written informed consent for the publication of this letter was obtained from the patient. A 51-year-old nonobese man with no history of spine disease presented for exploratory laparotomy. The patient was seated for epidural catheter placement and his back was prepped and draped in a sterile fashion. The T9–T10 interspace was identified by surface bony landmarks and a first attempt was performed at midline using a 17-Ga Tuohy needle (Arrow Inc, Reading, MA). After 2 needle redirections, there was persistent bony contact and the approach was abandoned. No out-of-the-ordinary pressure was applied to the needle. A second attempt was performed at the same interspace with the same needle through a left paramedian approach. Loss of resistance was obtained at 6.5-cm depth from skin. Additionally, identification of the epidural space was confirmed via pulsatile waveform on epidural waveform analysis through the needle (for educational purposes).1,2 A 19-Ga catheter (FlexTip Plus, multiport, Arrow Inc) was advanced through the needle, but it was impossible to thread it past 11.5 cm, corresponding to the tip of the needle. At that point, multiple maneuvers were attempted to pass the catheter without success, including injection of saline through the needle, 1-mm advancement of the needle, and rotation of the needle. A third attempt was performed at the same interspace with the same needle through a right paramedian approach with the same result. Close examination of the epidural needle revealed a small kink at the tip, making passage of the catheter impossible (Figure). When a new needle was used with the same approach, the catheter was passed easily and good analgesia was obtained. Other mechanical complications involving epidural needles have been described previously. Schlake et al3 described a case of separation of the hub from the needle shaft. Two cases of fractured Tuohy needle have been reported in obese parturients.4,5 Finally, Lipov et al6 described severe kinking of a Tuohy needle during epidural steroid injection in an obese patient. In the present case, it is likely that forceful bony contacts caused denting of the tip of the needle, which was not noticed until careful visual examination was performed. Another possibility, although much less likely, is that there was a preexisting manufacturing defect. Difficulties with threading an epidural catheter through the needle are not uncommon and often result in maneuvers such as advancing the needle further or rotating it, thereby increasing the risk of dural puncture. It is also sometimes interpreted as inappropriate position of the needle tip outside of the epidural space. In our opinion, anesthesiologists should be aware of the potential for a kinked needle tip and be particularly suspicious when evidence of proper epidural space identification such as convincing loss of resistance or pulsatile epidural waveform is present. We recommend careful examination of the epidural catheterization equipment before and after each insertion attempt, particularly if forceful bony contact has been applied.