Differences in efficacy and safety between intrathecal infusion devices in cancer pain.

BACKGROUND: Intrathecal infusion therapy is widely accepted for cancer pain patients when conventional analgesic treatments are not sufficient. There are different types of devices for carrying out this therapy: partially externalized devices (PED), used when life expectancy is under 3 months, and totally implanted devices (TID), when it is larger. Our objective is to compare the efficacy, functionality, and complication rate in both types. METHODS: We included 132 patients with mild-severe cancer pain, treated with intrathecal infusion therapy by fixed flow devices, PED, or TID, during the study time. Demographic, physical oncologic, and pain control data of the patients were recorded prior to starting therapy and at months 1, 3, and 6. Functionality status and complications were also collected from the patient's medical records and clinical files. RESULTS: Pain control improved after starting therapy, with an overall reduction of 4.75 points in VAS score at 1 month in the both groups, without significant differences between them, keeping it at 3 months and 6. 33.3% of the patients developed complications and were more frequent in the PED group, being catheter dislocation the most common. Patients with TID required more often hospital admission to solve the complication. CONCLUSIONS: Intrathecal infusion therapy has been shown to be a very effective and safe therapy for the treatment of moderate to severe oncologic pain. There are no significant differences between PED and TID in terms of degree of pain control, therapeutic success, efficacy on episodic or nocturnal pain, or the presence of serious complications.

Predictive factors for efficacy and safety of intrathecal infusion devices for oncological pain.

Introduction: In an important percentage of intrathecal infusion therapy, the pain after implantation of a spinal device does not improve. Our objective is to identify factors that can predict therapeutic success and complications, developing a predictive model based on univariate and multivariate analyses. Methods: Retrospective observational study, including 132 patients with oncological pain who were implanted with a fixed-flow device for intrathecal infusion. Four time points were established for data collection and, in addition to demographic and anthropometric data, variables related to oncologic pain pathology, initiation of therapy, pain control and complications were collected. Based on univariate and multivariate analyses, we performed predictive models on efficacy and complications. Results: The mean baseline pain intensity was VAS 7.78, and when comparing the values before implantation with those at month 1, we observed an overall decrease of 4.75 points, maintained at months 3 and 6. Nocturnal pain progressively decreased in incidence from 50.0% before implantation to 21.8%, 9.1% and 4.3% at 1, 3 and 6 months. Episodic pain was present in 90.1% of the patients before implantation (7.79 episodes/day), and at 6 months the incidence remained at 53.8%. Most of the patients (66.6%) had no complications related to therapy. We constructed a highly significant multivariate model for the efficacy of the therapy with a predictive capacity of 30.2% and composed of factors: absence of nocturnal pain before implantation and clinical improvement on day 2 after implant. Regarding the prediction of complications, it was not possible to achieve a significantly multivariate effective model. Conclusion: We identify two factors that predict therapeutic success in a multivariate model: the absence of nocturnal pain before implantation and the improvement of pain on the second day after implantation.