Dorsal Versus Ventral Intrathecal Catheter Tip Location and Effect on Dose Escalation and Opioid Use in Patients With Cancer Pain.

OBJECTIVES: In the practice of intrathecal drug delivery, consensus exists regarding the cephalad to caudad location of the catheter tip relative to dermatomal distribution of pain. However, data are lacking on the importance of dorsal vs ventral tip location relative to the spinal cord. We hypothesize that a dorsally placed catheter tip improves efficacy because of closer proximity to nociceptive pathways. MATERIALS AND METHODS: A retrospective review of 298 patients with cancer with intrathecal drug delivery systems implanted at the Huntsman Cancer Institute from May 2014 to June 2020 was performed. Patients were stratified by catheter tip location zones based on available radiographic studies. Patient-controlled intrathecal medication dose requirements and rate of change were compared with catheter zone and other variables, including the presence of adjuncts such as bupivacaine and ziconotide. RESULTS: A total of 158 patients were suitable for analysis demonstrating a dorsal tip in 63.9% (n = 101) and ventral tip in 36.1% (n = 57), with a median follow-up of 17 days (interquartile range [IQR], 10-24). There was no difference in daily dose change from implant to discharge between the dorsal group 8.2% (IQR, 0.0-41.5) and ventral group 20.8% (IQR, 0.0-66.7; p = 0.12). Daily dose change from discharge to follow-up was 2.6% (IQR, 0.0-7.1) in the dorsal group and 1.8% (IQR, 0.0-5.7) in the ventral group (p = 0.92). Catheter tip location had no impact on systemic opioid use. CONCLUSIONS: We did not find significant associations between dorsal vs ventral catheter tip location and measures of pain relief, including change in intrathecal dose or systemic opioid use.

T4 Erector Spinae Plane Block Relieves Postdural Puncture Headache: A Case Report.

Postdural puncture headache (PDPH) is a common complication of neuraxial anesthesia. The gold standard treatment for PDPH is an epidural blood patch (EBP). However, the risks of EBP, and patient willingness to undergo another attempted neuraxial procedure, can prevent patients from receiving this treatment. The erector spinae plane (ESP) block has been used in the treatment of acute postoperative and chronic pain secondary to many indications at many vertebral levels, and a prior case series describes two patients in which ESP block relieved tension headache. In our case report, we describe a novel use of the ESP block at the fourth thoracic vertebral level to relieve PDPH in a super morbidly obese patient with two prior inadvertent dural punctures.