1. John Hanlon MSc MD FRCPC Michael Gofeld MD FIPP

2. Background  Intrathecal pump drug refill can result in significant adverse events  Real-time ultrasound-guided pump access is a simple technique that may prevent such complications  The feasibility of teaching ultrasound-guided pump access to individuals with limited experience accessing intrathecal pumps is unknown

3. Study Design We evaluated the feasibility of ultrasound-guided intrathecal pump refill among seven novice trainees using unembalmed cadavers from the University of Washington Willed Body Program Prior to the study phase, each participant received a five minute teaching session on blind and ultrasound- guided pump access

4. Methods  Twenty random order pump access procedures performed by each subject:  10 blind, 10 ultrasound-guided  Low frequency ultrasound probe (MTurbo, SonoSite) and Medtronic pump refill kit were used  Performance videotaped for:  total procedure time  time from needle insertion to the port accessed  Success or failure determined by an expert faculty member  Participants questioned about their procedural confidence at time of study and three months later

5. Results – Table 1 Fellows (n= 7) Mean age (range)33 (32-35) Male (%)5 (71%) Residency completed Anesthesia PMR 6 (86%) 1 (14%) Prior Ultrasound experience (# of procedures) 0-25 26-50 >50 0 (0%) 1 (14%) 6 (86%) Comfort with Ultrasound based procedures Not at all Somewhat Very comfortable 0 (0%) 4 (43%) 3 (57%) Number of Intrathecal pump refills performed 0-10 >10 6 (86%) 1 (14%)

6. p < 0.01

7. p < 0.05

8. Results: Pocket fill and Confidence Number of unrecognized access failures (needle in subcutaneous tissue at procedure completion): Ultrasound-guided: 1/70 (1.4%) Blind: 3/70 (4.3%) Greater confidence in ability to access an intrathecal pump using a blind vs. ultrasound-guided approach? Ultrasound-guided: 7/7 (100%) Blind: 0/7 (0%)

9. Three Month Follow-Up Fellows (n=7) Mean number of “blind” pump accesses? (range) I feel confident with this method 1 (0-4) 7 (100%) Mean number of “US-guided” pump accesses? (range) I feel confident with this method 0 (0) 7 (100%) What would be your approach to refilling an intrathecal pump in a morbidly obese pt? Blind Ultrasound-guided Examine patient first to decide 0 (0%) 5 (71%) 2 (29%)

10. Limitations Pre-clinical pilot study Small number of participants Cadaver model Procedural time as an endpoint Measurement Needle passes and “patient comfort” unmeasurable Economy of motion (path length / movements) not measured Participant Bias

11. Conclusions Ultrasound-guided pump access is a simple technique that can be easily taught to trainees While the overall procedure takes longer than a blind approach, it is still efficient and may result in improved patient comfort due to decreased time from needle insertion to port access It is possible that Ultrasound-guided pump access may result in decreased inadvertent “pocket fills” Confidence in the utility of ultrasound-guided pump access is retained at three months even in the absence of ongoing experience

12. Acknowledgements University of Washington Willed Body Program Participants