Subarachnoid Catheter
A catheter inadvertently placed in the subarachnoid space during intended epidural catheterization. Requires recognition and appropriate management to prevent complications from intrathecal drug injection.
Full Definition
A subarachnoid catheter is an epidural catheter that has been unintentionally threaded through a dural puncture into the subarachnoid space during attempted epidural catheter placement. This complication can occur when the epidural needle punctures the dura but cerebrospinal fluid is not immediately recognized, and the catheter is advanced into the intrathecal space. Recognition may occur through CSF aspiration from the catheter, lack of resistance to injection, or unexpectedly high block levels with test doses. Management options include removing the catheter and re-attempting epidural placement at a different level, or intentionally using the catheter for continuous spinal anesthesia with appropriately reduced drug doses. The decision depends on clinical circumstances, urgency of the case, and institutional protocols. Failure to recognize subarachnoid placement can result in total spinal anesthesia or cardiac arrest if epidural doses are administered intrathecally.
Usage
Usage note: Be precise about anatomical location; 'subarachnoid' is more accurate than 'spinal' when referring to catheter placement.
In Context
- "CSF aspiration from the catheter indicated subarachnoid placement, prompting catheter removal and re-insertion." — Procedure note
- "The anesthesiologist elected to use the subarachnoid catheter for continuous spinal anesthesia with reduced drug concentrations." — Anesthesia record