Can Osteopathic Medical Students Accurately Measure Abdominal Aortic Dimensions Using Handheld Ultrasonography Devices in the Primary Care Setting?

Context: The US Preventive Services Task Force (USPSTF) recommends a 1-time ultrasonography (US) screening for abdominal aortic aneurysm (AAA) to reduce AAA-specific mortality in men aged 65 to 75 years who have ever smoked. A 2015 study concluded that less than 50% of at-risk primary care patients are screened for AAA. To increase screening rates, it would be beneficial to train other health care professionals in accurately measuring abdominal aortic dimensions.

Objective: To determine whether osteopathic medical students can use handheld US machines to measure abdominal aortic diameters as accurately as an experienced US technologist.

Methods: Three osteopathic medical students underwent 8 hours of US training with a board-certified radiologist to measure abdominal aortic dimensions using a handheld US device. After the training, students independently conducted AAA US screenings at a clinic on participants meeting USPSTF AAA screening criteria. Transverse and anteroposterior measurements were taken at 3 sites: celiac axis, inferior to the renal arteries, and superior to the iliac bifurcation. A US technologist then measured the participants' aortic diameters in the radiology department at another facility. The measurements from both reports were then compared using a 2-sample t test.

Results: The aortic diameter was measured in 16 participants with a mean (SD) body mass index of 26.7 (3.6). The mean (SD) difference between novice and expert measurement of the abdominal aorta was -0.15 (0.23) cm. No statistically significant difference was found between the US measurements completed by students and a US technologist (t=-1.38, P=.09). None of the participants met the criteria for AAA (>3.0 cm), with the largest abdominal aorta scanned by experts measuring 2.86 cm.

Conclusion: When properly trained, osteopathic medical students can accurately measure abdominal aortic diameters using a handheld US device. Training more medical students in ultrasonography would offer increased screening opportunities and possibly reduce AAA-related mortality. Further studies are needed to assess the ability of osteopathic medical students to accurately measure AAAs, as no participants in this study met the criteria for AAA.