Simulation-based ultrasound-guided lumbar puncture training using a flipped classroom: a single-arm pilot programme evaluation

Background Traditional landmark-guided lumbar puncture (LP) has high failure rates among novice emergency medicine (EM) clinicians. While ultrasound guidance improves success, structured training models remain limited and expensive. We evaluated a cost-effective, simulation-based flipped classroom curriculum for teaching ultrasound-guided LP to EM residents and trainees. Methods We developed a high-fidelity, custom 3D-printed spinal simulator costing approximately $40 USD per unit. The curriculum utilized a flipped classroom model combining online theoretical modules with hands-on, deliberate practice. Results Twenty-two participants (9 EM residents, 13 PGY trainees) completed the training programme; paired landmark-versus-ultrasound OSCE data were available for the seven residents who completed both phases. Among EM residents with paired data (n = 7), the ultrasound-guided phase OSCE completion rate was 100%, compared to 43% during the earlier landmark phase (a large but statistically non-significant difference, p = 0.125, McNemar’s exact test). The ultrasound-guided phase was associated with higher rubric-rated performance scores and overall ratings (nominally significant, uncorrected for multiple comparisons); needle passes (median 7 vs. 12) and procedure times were also lower but did not reach statistical significance in this small paired sample. Both groups reported significantly lower procedural stress with ultrasound guidance, with a smaller, non-significant increase in confidence. Conclusions A flipped classroom curriculum utilizing a low-cost, 3D-printed simulator is a feasible and well-received educational innovation for teaching ultrasound-guided LP, with encouraging but preliminary performance findings for EM residents that require confirmation in controlled studies.