Intrathecal Analgesia via a Percutaneous Port With Patient-Controlled Intrathecal Analgesia for the Management of Movement-Evoked Breakthrough Cancer Pain of Refractory Lower Extremity Cancer Pain: A Retrospective Review

BACKGROUND: Intrathecal analgesia (ITA) is a valuable treatment option for refractory cancer-related pain. However, there is still no general consensus on the analgesic effect of movement-evoked breakthrough pain (MEBTP) in the ITA setting. OBJECTIVES: This study aimed to conduct a retrospective observational study to examine the effect of ITA via percutaneous port (ITAPP) with patient-controlled ITA (PCIA) on analgesic efficacy, emphasizing MEBTP in patients with refractory lower extremity cancer pain. STUDY DESIGN: A retrospective chart review included all patients with refractory lower extremity cancer pain who received ITAPP at our hospital between January 2017 and December 2020. METHODS: Data on the Numeric Rating Scale scores of spontaneous resting pain intensity (SRPI) and MEBTP intensity (MEPI), opioid doses, and perceived time to onset were collected from medical records prior to ITAPP and at a one-month postimplant visit. RESULTS: A total of 16 patients were included in the study group. Mean SRPI decreased from 8.75 pre-ITAPP to 3.75 post-ITAPP (P < 0.05); mean MEPI fell from 8.83 pre-ITAPP to 4.25 post-ITAPP (P < 0.05); mean daily morphine equivalent dosing decreased from 360 mg/d to 48 mg/d (P < 0.05); and mean daily morphine equivalent dosing for MEBTP decreased from 87 mg/d to 6 mg/d (P < 0.05). Both total and breakthrough dosing of conventional opioid medications significantly decreased following the initiation of ITAPP with PCIA. The mean perceived time to onset with conventional MEBT medications was 38 minutes, and the mean perceived time to onset with PCIA was 8 minutes (P < 0.05). LIMITATIONS: An effective analysis of IT opioid efficacy was not possible because the power of such a small sample size was low. Second, it is a retrospective study without long-term follow-ups. CONCLUSIONS: In patients with refractory lower extremity cancer pain, ITAPP with PCIA was associated with improved pain control. Compared with conventional MEBTP regimens, appropriate ITAPP with PCIA provided superior analgesia and a much faster onset of action.