"Pocket ultrasounds are a point-of-care game changer, equivalent to the initial development and use of the stethoscope," said Cecilia B. Leggett, MD, an obstetrics and gynecology resident at Cedars-Sinai and first author of the study.
Leggett said the idea to use the handheld devices came to her while scouring a labor room desperately seeking a power outlet for the ultrasound machine. She thought about the pocket imaging probes used by her colleagues in internal medicine.
"Ultrasound machines are heavy, need to be wheeled on a cart from one location to the next, require a power outlet and take at least a minute to load," Leggett said. "This means at every patient interaction a physician needs to think about whether or not to do an ultrasound."
These steps can translate to delays in diagnosis and care. But pocket ultrasounds make it possible for clinicians to image pregnant women and their fetuses in seconds, according to Leggett.
Leggett approached her supervisors about making the technological switch. Although they were open to the change, they needed evidence pocket ultrasounds are just as reliable as standard ultrasounds. Leggett decided to find out.
Leggett's study included 100 patients who were 19 to 39 weeks pregnant. Patients were recruited to participate in the study during their scheduled ultrasound visits. Those who chose to participate underwent a full obstetric scan with both a standard ultrasound machine and a pocket ultrasound.
An analysis of the data showed the pocket ultrasound was just as reliable as the standard ultrasound. The two imaging methods produced consistent measurements for fetal weight, fetal cardiac activity, presence of a fetal bladder, amniotic fluid, placental location and the position of the fetus.
Pocket ultrasound probes, which connect to a smartphone or tablet for image display and do not require a power outlet, are now widely used at Cedars-Sinai.
“This study contributed important data proving this is a valid clinical tool for use in pregnant patients,” said senior author Melissa S. Wong, MD, MHDS, assistant clinical professor in the Department of Obstetrics and Gynecology at Cedars-Sinai and a mentor to Leggett.
Leggett said pocket ultrasounds can be especially useful in low-resource settings.
"In some settings, like clinics in developing countries, power outlets may not even be available or the ultrasound machines may be prohibitively expensive," Leggett said. "Pocket ultrasounds can also be used to image patients who live in remote areas, whether in the U.S. or elsewhere."
Leggett and colleagues have carried out another study that found it takes clinicians about 14 minutes to make a diagnosis with a standard ultrasound as compared with just over two minutes with a pocket ultrasound.
The benefits may extend beyond patient care, though.
"Having that probe in your pocket—knowing it's right there and easy to use—is great for provider satisfaction," Leggett said. "I've heard from the residents that it does contribute to a bit less of a sense of burnout on a busy shift."
Other Cedars-Sinai researchers who worked on the study include Mariam Naqvi, MD; Tania Esakoff, MD; Marcio Diniz, PhD; and Melissa Wong, MD, MHDS.