2026 SOAP Annual Meeting

Recognize signs of delayed intravascular migration of an epiduralcatheter after initially normal placement
Identify risk factors and mechanisms contributing to epiduralcatheter knot formation
Describe safe management strategies when encounteringresistance during catheter removal
Apply preventative techniques to reduce mechanicalcomplications of neuraxial anesthesia

A 32-year-old ASA II patient underwent epidural catheterplacement at the L4–L5 level for labor analgesia. Loss-of-resistance to saline was achieved without difficulty, and thecatheter was advanced to 5 cm past depth of loss-of-resistance.Initial aspiration was negative, and a test dose produced nohemodynamic or neurologic changes.
Approximately 2 hours later, the patient reported worsening painwith contractions. Examination revealed:
9/10 pain with contractions
Tinnitus
Sensory level to cold above L1
Repeat aspiration yielded blood, raising concern forintravascular migration.
Catheter removal was attempted but met with resistance. Aftermultiple repositioning attempts, the catheter was successfullyremoved using slow, steady traction. Inspection revealed adistal knot.
The patient experienced no neurologic deficits, bleeding, orvascular complications at time of discharge.

This case highlights several important clinical considerations:

Delayed intravascular migration can occur despite initiallynegative aspiration and test dosing; inadequate analgesia shouldprompt reassessment
Advancing the catheter beyond recommended depth (typically 3–5cm) may increase the risk of looping and knot formation
Resistance during catheter removal should raise suspicion formechanical complications such as knotting
Forceful traction must be avoided due to risks of:
Catheter fracture
Retained fragments
Vascular or neurologic injury

Best Practices Include:

Limiting catheter advancement to 3-5 cm
Frequent reassessment of analgesia quality
Gentle, patient repositioning during difficult removal
Maintaining high suspicion for delayed complications

Simultaneous intravascular migration and knot formation of anepidural catheter is an exceptionally rare but clinically significantcomplication (Approximately 1 in 3.3 million). Early recognition,careful management, and adherence to safe neuraxialtechniques are critical to minimizing patient harm and improvingoutcomes.

2026 SOAP Annual Meeting

Simultaneous Intravascular Migration and Knot Formation of an Epidural Catheter: A Rare Mechanical Complication

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