Intrathecal Baclofen Infusion Pumps in the Treatment of Spasticity: A Retrospective Cohort Study in a Portuguese Centre

INTRODUCTION

Spasticity is a complex problem in patients with neurological disorders and may distress their quality of life. Intrathecal baclofen infusion pumps reduce spasticity with low doses and minimal side effects but are not free from complications. We aimed to evaluate the efficacy and safety of intrathecal baclofen infusion pumps as well as patients' satisfaction.

MATERIAL AND METHODS

Retrospective cohort study including all intrathecal baclofen infusion pumps placed up to December 2015. Demographic characteristics, clinical diagnoses, date of placement or withdrawal/replacement of intrathecal baclofen infusion pumps, baclofen dosage and complications of intrathecal baclofen infusion pumps were collected. Assessments from the Ashworth and Penn's scales, Katz index and patients' global satisfaction were analysed.

RESULTS

In 19 years we placed 251 intrathecal baclofen infusion pumps in 155 patients. The mean age was 41.1 ± 15.8 years. The most frequent conditions were: trauma (34%), cerebral palsy (14%), multiple sclerosis (12%) and stroke (12%). Eighty-five patients (55%) required a second pump, and eleven (7%) a third one. The lifetime of the first pump was 72 (36 - 89) and the total follow-up time was 96 (9 - 132) months. The causes of withdrawal/replacement were: battery failure (57%), catheter migration/kinking (24%), infection (14%) and pump displacement/exteriorization (7%). The complication rate was 0.21 events/month. There was a significant improvement in the Ashworth and Penn's scales after the placemen of intrathecal baclofen infusion pumps (p < 0.001 for all diagnoses) and the patients were satisfied with the treatment.

DISCUSSION

The incidence of complications was within range of other international studies despite our long follow-up time. Events per month, loss to follow-up, re-intervention rate, incidence of infection and mortality were similar to other studies.

CONCLUSION

Intrathecal baclofen infusion pumps are safe and effective in the treatment of spasticity. Infusion pumps provide a high level of satisfaction regarding treatment and quality of life.

High-Resolution Three-Dimensional Computed Tomography for Assessing Complications Related to Intrathecal Drug Delivery

BACKGROUND

The assessment of the functionality of intrathecal drug delivery (IDD) systems remains difficult and time-consuming. Catheter-related problems are still very common, and sometimes difficult to diagnose.

OBJECTIVES

The aim of the present study is to investigate the accuracy of high-resolution three-dimensional computed tomography (CT) in order to detect catheter-related pump dysfunction.

STUDY DESIGN

An observational, retrospective investigation.

SETTING

Academic medical center in Germany.

METHODS

We used high-resolution three dimensional (3D) computed tomography with volume rendering technique (VRT) or fluoroscopy and conventional axial-CT to assess IDD-related complications in 51 patients from our institution who had IDD systems implanted for the treatment of chronic pain or spasticity.

RESULTS

Twelve patients (23.5%) presented a total of 22 complications. The main type of complication in our series was catheter-related (50%), followed by pump failure, infection, and inappropriate refilling. Fluoroscopy and conventional CT were used in 12 cases. High-resolution 3D CT VRT scan was used in 35 instances with suspected yet unclear complications. Using 3D-CT (VRT) the sensitivity was 58.93% - 100% (CI 95%) and the specificity 87.54% - 100% (CI 95%).The positive predictive value was 58.93% - 100% (CI 95%) and the negative predictive value: 87.54% - 100% (CI 95%).Fluoroscopy and axial CT as a combined diagnostic tool had a sensitivity of 8.3% - 91.7% (CI 95%) and a specificity of 62.9% - 100% (CI 95%). The positive predictive value was 19.29% - 100% (CI 95%) and the negative predictive value: 44.43% - 96.89% (CI 95%).

LIMITATIONS

This study is limited by its observational design and the small number of cases.

CONCLUSION

High-resolution 3D CT VRT is a non- invasive method that can identify IDD-related complications with more precision than axial CT and fluoroscopy.

Catheter-tip Granulomas Associated with Intrathecal Drug Delivery--A Two-Center Experience Identifying 13 Cases

BACKGROUND

Intrathecal (IT) drug therapy with implanted pumps is an effective treatment modality for chronic pain and/or spasticity, especially after non-invasive treatment has failed. Long-term use of intrathecal opioids may cause formation of inflammatory masses at the tip of intrathecal catheters, possibly leading to neurological deficits and/or catheter revision.

OBJECTIVE

We aimed to identify risk factors for catheter-tip granuloma (CG) formation.

STUDY DESIGN

Retrospective study.

SETTING

Tertiary Spine Centers in Germany and Switzerland.

METHODS

We retrospectively reviewed data at 2 Swiss centers (Kantonsspital St. Gallen, Swiss Paraplegic Centre Nottwil) between 01/1994 and 10/2013. Collected data were age at operation, gender, smoking status, previous spinal operations, spinal level of catheter-tip, clinical symptoms, catheter testing with contrast agent, applied drugs, drug concentration, as well as cumulative daily drug dosages.

RESULTS

Thirteen patients with a mean age of 52.6 years and CG formation after a mean of 6.9 years of follow-up were identified and compared to 54 patients of similar age and length of follow-up (48.6 years, P = 0.535; follow-up 5.3 years, P = 0.236) without CG. In the analysis of risk factors, catheter ending in the middle thoracic spine (Th4-8; 38.5 vs. 6.5%; P = 0.010), previous spinal surgery (75 vs. 41%; P = 0.051), and chronic pain as an underlying primary symptom for IT drug therapy (100 vs. 56%, P = 0.003) were associated with CG formation. IT drug therapy for spasticity appeared to be much less associated with CG formation (0 vs. 44%, P = .0003). As the symptomatology is closely related to the medical treatment applied, patients with CG were more likely to be treated with IT morphine (77 vs. 20%; P < 0.001), and as tendency with IT clonidine (54 vs. 26%; P = 0.092) and IT bupivacaine (46 vs. 20%; P = 0.077). Average in-pump morphine concentration (30.3 vs. 19.5 mg/mL; P = 0.05) as well as average daily dose of morphine (12.5 vs. 6.2 mg/d; P = 0.037) were significantly higher in the CG group. Smoking could not be identified as risk factor for CG formation.

LIMITATIONS

Limitations include the retrospective approach, the limited group size of granuloma patients, as well as missing data in the investigated patient groups.

CONCLUSION

Our patient cohort with CG differed in some features, of which some like catheter localization, choice, dosage, and the concentration of drugs are potentially modifiable. These results could contribute to the prevention of CG in the future.

Intrathecal analgesia: time to consider it for your patient?

When systemic analgesics or antispasmodics fail to control chronic pain or cause intolerable adverse effects, an intrathecal drug delivery system may be the best bet.

Rising complication rates after intrathecal catheter and pump placement in the pediatric population: analysis of national data between 1997 and 2006

BACKGROUND

Intrathecal delivery of baclofen (ITB) is effective at controlling spasticity. However, it requires the placement of a catheter into the intrathecal space, and a pump with a reservoir for the medication. The process of placing the catheter and pump are prone to complications.

OBJECTIVES

The objective of this paper is to determine factors contributing to rising complication rates after intrathecal catheter/pump placement in a national sample of pediatric patients.

STUDY DESIGN

This was a retrospective observational database study.

METHODS

We queried the Kids' Inpatient Database for all children greater than 4 years old and under 20 years old for the years 1997, 2000, 2003, and 2006 who had an intrathecal catheter and pump placed. We then compared demographics and hospital characteristics of patients with and without complications. We performed univariate and multivariate analyses to determine the relative contribution of various factors to the development of complications.

RESULTS

We identified 2,843 patients who met our criteria, and 514 of these patients had one or more complications after placement of intrathecal pump/catheter. There were 1.14 complications per patient. The complication rate was 10.2% in 1997, and increased to 21.9% in 2006. Mechanical complications were the most common type of complication in this population, account for nearly two-thirds of all complications occurring. Age, hospital type, hospital size, and admission source were independent predictors of complications.

LIMITATIONS

We did not have access to ASA status, operative details, and access to patient charts.

CONCLUSIONS

Complication rates after placement of intrathecal pump/catheters have increased in the pediatric population between 1997 and 2006 mainly due to an increase in mechanical complications.