Learner Assessment of an Ocular Tonometry Task Trainer (1090-002346) (Research Abstract Oral: Procedure)
Start time: Monday, January 25, 2021, 8:00 AM End time: Monday, January 25, 2021, 9:00 AM Session Type: Research Abstracts (Completed Studies)
Intraocular pressure (IOP) measurement is vital when assessing patients for ocular pathology. Novice learners are uncomfortable with this procedure due to fear of causing injury or discomfort. Commercially available task trainers carry heavy costs, and do-it-yourself task trainers focus on non-tonometry ophthalmology procedures (1-4). Foley catheter balloons and marbles have been used to teach tonometry. These models do not demonstrate relevant anatomy with accurate tactile feedback and the ability for the instructor to vary anterior chamber pressure. We are not aware of any model that provides these features. We developed a task trainer possessing these qualities for instructing medical students and emergency medicine (EM) interns. We hypothesized that use of this model would result in a significant improvement in learners’ comfort in performing tonometry and confidence in the accuracy of their measurements.
Our model used swine eyes with an angiocatheter inserted through the optic nerve sheath into the vitreous chamber, pressurized via IV tubing and a syringe, to create a model with variable IOP. We incorporated this model into our EM medical student procedure lab and our EM intern ophthalmology boot camp (5). Participation in the study was voluntary, and learners had access to the model and accompanying instruction regardless of their participation. Participants completed a pre-test prior to the instructional session, providing data on basic demographics, knowledge of the procedure, and comfort and confidence related to the procedure. Learners then received instruction on the use of the tonometer followed by guided practice using the swine eye model. After the session, they completed a post-test. The Wilcoxon Signed-Rank test was used to analyze changes in learner comfort and confidence. This study was deemed to meet exemption criteria by the Vanderbilt University Medical Center IRB.
Thirty-six learners in total participated in the study, including 13 EM interns and 23 medical students. All participants completed a pre-test and post-test. Of the medical students, 18 were in their fourth year of medical school, while 5 were in their third year. Of these 36 learners, 16 had never received training on tonometry, 10 had never seen it performed on an actual patient, and 18 had never personally performed the procedure. Among all learners, mean comfort with performing this procedure had a statistically significant increase from 3.26 to 7.64 (Z = -4.95, p < 0.005). Subjects’ mean confidence in the accuracy of their measurements also had a statistically significant increase from 3.11 to 7.56 (Z = -4.8, p < 0.005). The significance of these increases remained when the results for medical students and interns were calculated separately.
We successfully constructed a realistic and inexpensive model for IOP measurement that allowed learners to practice ocular tonometry. This model was created using swine eyes and materials available in a typical emergency department. Only half of our learners had ever performed this procedure before, and nearly one-third had never seen the procedure performed. Both medical students and EM interns demonstrated increases in comfort with performing the procedure and confidence in the IOP measurements they obtained. These increases were both statistically significant and large in effect. Although these results do not directly support an improvement in clinical practice, they demonstrate a poor baseline comfort and confidence related to this procedure among most novice learners, which improved greatly after the use of this task trainer.