Long-term Outcome and Adverse Events of Intrathecal Opioid Therapy for Nonmalignant Pain Syndrome.

OBJECTIVE: Intrathecal (IT) opioid pumps are one therapeutic cornerstone of refractory nonmalignant pain syndromes. The aim of this study was to evaluate the efficacy of and surgical and pharmacological complications of IT pumps beyond a time span of 10 years.

METHODS: In this retrospective single-center cohort study, 27 patients (14 female, 13 male, age 64.0 ± 8.9 [median, 1 SD] years) were identified. Pain intensity using the numeric rating scale (NRS), pain and IT pump characteristics, and complications were analyzed. The German Pain Questionnaire was used to investigate the physical and mental health status.

RESULTS: Overall time of IT therapy from first implantation to last follow-up was 20.4 ± 6.0 years. Time to implantation of the second pump (n = 18) was 10.0 ± 5.3 years, and between the second and third pump (n = 6) 6.5 ± 2.7 years; 2 patients received their fourth pump 6 years later. The NRS score was 9.0 ± 0.9 before implantation, 7.0 ± 1.8 1 year after implantation, and 4.0 ± 2.3 at the last follow-up. IT drug dose remained stable after 3 years. Opioid intoxications occurred in 3 patients (10%). One patient (3%) underwent revision surgery due to a catheter infection. Drug side effects occurred in 4 patients (14%). Our patient group had pain-related restrictions in physical activities with menial impact regarding mental and emotional stress.

CONCLUSION: Even after a time span of over 15 years and several exchanges of pump systems, pain intensity was still reduced. After 3 years, IT drug dose remained unchanged with low side-effect and complication rates.