A comparison of a homemade central line simulator to commercial models.

BACKGROUND

Simulation is quickly becoming vital to resident education, but commercially available central line models are costly and little information exists to evaluate their realism. This study compared an inexpensive homemade simulator to three commercially available simulators and rated model characteristics.

MATERIALS AND METHODS

Seventeen physicians, all having placed >50 lines in their lifetime, completed blinded central line insertions on three commercial and one homemade model (made of silicone, tubing, and a pressurized pump system). Participants rated each model on the realism of its ultrasound image, cannulation feel, manometry, and overall. They then ranked the models based on the same variables. Rankings were assessed with Friedman's and post hoc Conover's tests, using alphas 0.05 and 0.008 (Bonferroni corrected), respectively.

RESULTS

The models significantly differed (P < 0.0004) in rankings across all dimensions. The homemade model was ranked best on ultrasound image, manometry measurement, cannulation feel, and overall quality by 71%, 67%, 53%, and 77% of raters, respectively. It was found to be statistically superior to the second rated model in all (P < 0.003) except cannulation feel (P = 0.134). Ultrasound image and manometry measurement received the lowest ratings across all models, indicating less realistic simulation. The cost of the homemade model was $400 compared to $1000-$8000 for commercial models.

CONCLUSIONS

Our data suggest that an inexpensive, homemade central line model is as good or better than commercially available models. Areas for potential improvement within models include the ultrasound image and ability to appropriately measure manometry of accessed vessels.