Disappearance of spinal catheter tip due to catheter stretching: a case report

Continuous spinal anesthesia (CSA) offers precise, prolonged neuraxial anesthesia suitable for high-risk patients. This technique minimizes hemodynamic instability but comes with notable challenges. Vigilant catheter management is crucial to avoid complications, including the risk of catheter retention. We report a case where the mechanical properties of a spinal catheter led to diagnostic uncertainty.

An ASA4 patient underwent a revision of total knee replacement surgery under CSA using a Pajunk IntraLong catheter set. Following successful insertion, the surgery proceeded uneventfully. During catheter removal, the expected tip markings were absent, raising concern for a retained fragment. Imaging confirmed no retained foreign body. To investigate further, stretching of a new catheter replicated the disappearance of tip markings. This finding suggested that the catheter's material had the potential to stretch under tension, leading to fading of the markings and mimicking a retained fragment.

This case underscores the need for awareness of the mechanical properties of spinal catheters, especially their potential for stretching and loss of tip markings. Understanding these characteristics can prevent unnecessary imaging and reduce patient and clinician anxiety.