2012 Poster Sessions : HaemoBot: a Robotic System for IV Insertion

Student Name : Reuben Brewer
Advisor : Kenneth Salisbury
Research Areas: Artificial Intelligence
Over 250 million intravenous (IV) catheterizations take place in the United States annually, and 28% of
those insertions fail on the first attempt in normal adults. The failure rate for children is as high as 54%. At least 27% of patients require 3 attempts or more to obtain a successful insertion. Beyond producing
pain and disfiguration, failed sticks can result in permanent injury such as venous scarring and nerve damage. In patients with chronic illnesses that require repeated insertions, the veins can scar to an extent that insertions are impossible in hands or arms.

We are developing an assistive robotic system that will make IV catheterization more reliable and less painful. Our system enhances the sensory and motor abilities of human practitioners while keeping the human in full control of the insertion via a haptic device (high degree-of-freedom joystick that can transmit forces to the user's hand). As an example, practitioners often report feeling a “pop” as the needle and catheter penetrate the vein wall. Failure to feel this sensory cue often causes doctors to insert the needle too far and penetrate the back-wall of the vein. However, our robot can reliably detect this “pop” as a force/acceleration spike and automatically slow the practitioner’s hand to prevent back-wall penetration.

Practitioners often have great difficulty seeing or feeling small veins, as found in women and children, or veins that lie beneath a layer of fat, as found in children and obese patients. One way to visualize veins that are particularly difficult to detect is the use of infrared imaging. We have developed an infrared imaging system and algorithm that searches infrared images of the hand for venous bifurcations as insertion sites. Such automatic vein-finding can be used to suggest insertion points to a human practitioner, or for autonomous insertion altogether.

Our robot gives full motion control of the needle and catheter and is designed with clinical convenience and safety in mind. We are investigating motions that the robot can perform to facilitate insertion that are too difficult for a human practitioner. To provide a better understanding of the mechanics and limitations
of IV insertion by human practitioners, we have conducted a clinical study with the Stanford Department of Anesthesiology, wherein 30 patients underwent IV insertions with highly instrumented IV needles so that we could examine the forces, accelerations, and motions during IV insertions.

Reuben Brewer is a Mechanical Engineering Ph.D. candidate in Professor Ken Salisbury's robotics lab. His research focuses on medical robotics and electromechanical design. Beyond his current thesis topic of
robotic IV insertion, Reuben has worked on medical projects including force control of small permanent magnets inside the body for minimally-invasive procedures and devices for performing faster, less invasive colonoscopies. His other electromechanical designs include development of a spherical haptic device, a highly dexterous robot hand, the hardware for a low-cost 7 degree-of-freedom robot arm, and the proof-of-concept omnidirectional platform for the PR1 personal robot that was later adapted into the platform for Willow Garage's PR2 personal robot. Beyond research, Reuben is interested in teaching students how to design and fabricate the mechanical hardware of robots. He developed and is colecturing the course, "CS235: Applied Robot Design for Non-Robot-Designers" with has advisor, Ken Salisbury. Reuben received his MS in Mechanical Engineering from Stanford University and BS in
Mechanical Engineering from Johns Hopkins University.