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.