Ultrasound guidance versus landmark guidance for intrathecal baclofen pump refill: A randomized pilot study

Background: Refilling difficult-to-access intrathecal baclofen (ITB) pumps by a trainee can result in longer procedures, more needle punctures, and more frequent attending interventions. Though ultrasound guidance can be used, there has not been an investigation into the impact of ultrasound guidance on refill outcomes. Objective: To determine the feasibility of ultrasound guidance during difficult ITB refills to improve the experience of patients and providers. Design: Nonblinded, randomized controlled trial with crossover element. Setting: Outpatient clinic at a tertiary academic rehabilitation hospital. Participants: Patients ≥18 years old with historically difficult refills who were scheduled for repeat refills. “Difficult” was defined as body mass index > 30.0, a deep/tilted pump, previously requiring >1 skin puncture, or previously needing special positioning to access. Interventions: Consented participants were randomized into a template-guided group (control) or an ultrasound-guided group (experimental) using a coin flip. Patients were crossed over if (1) a second refill occurred during the study period or (2) the randomized technique failed. Main Outcome Measures: The primary measure was time spent with needle under skin (seconds). Number of needle punctures and needle passes, frequency of attending intervention, pain during and after the procedure, patient satisfaction, and practitioner perceived difficulty were investigated. Results: Seventeen patients underwent 21 refills (12 template guided and 9 ultrasound guided). No patients experienced adverse events. Although without statistically significant difference, the average time in the experimental group was shorter than the control (175 seconds vs 401 seconds), there were fewer episodes of multiple needle punctures (0 vs 2), multiple needle passes (2 vs 5), and attending interventions (0 vs 3) in the experimental group. No significant/clinical difference was found in pain during procedure, pain after procedure, patient satisfaction, or practitioner subjective difficulty. Conclusions: This pilot study demonstrates that ultrasound-guided ITB refills may reduce time spent with the needle in the skin, number of needle punctures, number of needle passes, and frequency of attending intervention during trainee refilling of pumps that are difficult to access.