Prototype ultrasound-guided robot accurately and safely
draws blood.
Could robots one day replace phlebotomists in
performing routine venipuncture? Researchers at Rutgers University–New Brunswick
demonstrated the efficacy and safety of using a hand-held robotic device to draw
blood in a small cohort of patients, setting the stage for this possibility. “A
device like ours could help clinicians get blood samples quickly, safely, and
reliably, preventing unnecessary complications and pain in patients from
multiple needle insertion attempts,” said lead author Josh Leipheimer, a
biomedical engineering doctoral student, in a statement.
Leipheimer and his
colleagues said this is the first study to assess an automated blood drawing and
testing device in human subjects.
Phlebotomy success rates vary, depending on
patient physiology and the experience of the phlebotomist. Although venous blood
draws are a common clinical procedure, they fail often in vulnerable patients
who are emaciated or those who don’t have palpable or visible veins.
“Difficulties in obtaining venous access result in missed sticks and injury to
patients and typically require alternative access pathways and additional
personnel that lengthen procedure times, thereby creating unnecessary costs to
healthcare facilities,” the authors summarized.
The device, an ultrasound
image-guided robot, combines miniaturized robotics with 2D ultrasound imaging to
identify and cannulate vessels in a patient, said Leipheimer, who developed it
with colleagues Martin Yarmush, MD, PhD, Max Balter, PhD, and Alvin Chen, PhD.
Ultrasound imaging provides the position of a vessel, which the device uses to
determine where to insert the needle. Force sensors along the needle axis record
the insertion force and detect when the needle has successfully punctured the
vessel.
“Because of the precise needle placement and control, along with the
2D ultrasound imaging, the device provides improvement in first-stick accuracy
and completion time and in theory would require minimal training compared to
traditional venipuncture,” Leipheimer explained.
To make it easier to use,
the team modified the technology from a benchtop to a hand-held format. The new
model still has that “human-supervised” element but retains the benefits of
automated vessel identification and cannulation, Leipheimer said. He and his
colleagues used the device to obtain a venous blood sample from the peripheral
forearm veins of 31 participants, 25 of whom had easy-to-access veins.
Among
this small cohort, the device had a success rate of 87%, reaching 97% among
those whose veins were easily accessible, meeting or exceeding clinical
standards. The research team was quick to point out that it wasn’t trying to
directly compare the device against experienced phlebotomists. “The intention of
this device is to improve venipuncture success rates among all patient
demographics, without requiring clinicians to have extensive past experience in
obtaining venous access,” they clarified.
The hope is this tool could improve
success rates and procedure times, especially in patients who have had a history
of difficult venous access, Leipheimer said.
Next steps are to conduct a
larger and more controlled study, comparing the device’s performance directly
against trained clinicians in a clinical environment. Larger studies would help
assess risks and benefits, to ready the device for the U.S. Food and Drug
Administration’s approval process for medical devices.
“Additionally, we are
investigating extending the applications of this technology into other areas of
vascular access as well, such as arterial line placement and other percutaneous
procedures,” Leipheimer said.