Thursday, April 25, 2013

A group of mechanical and materials engineering students from UAB School of Engineering capillary_articleL to R: Mark Haynes, Clay Shelton, Claire McCall, & Satyam Patelwere asked to develop a device to simulate capillary refill on a medical training dummy. Dr. Nancy Tofil from Children’s of Alabama Pediatric Simulation Center introduced the idea and provided insight to the students. Dr. Tofil explained the importance of medical professionals utilizing capillary refill of patient’s to determine the patient’s health status. A capillary refill simulator would provide a way to train medical professionals on capillary refill.

Capillary Refill is a technique used in the medical field, mainly in pediatrics, to determine the body temperature and current health status of a patient. When pressure is applied anywhere on the body, the blood that runs through the capillaries in that part of the body is expelled from the capillaries. When the pressure is released, there is a visible difference in skin coloration when that area is compared to its surrounding area. In a healthy individual, the blood will return to capillaries within 0.2-2 seconds. If the patient’s body temperature is below normal body temperature (98.6° F) or if the patient is in shock, the blood may take up to 8 seconds to return to the capillaries and means that the patient is not experiencing normal blood flow.  This indicates that immediate medical action needs to be taken. If the patient’s body temperature is above normal body temperature, the blood may return slightly faster than that of a healthy person as long as the patient is not in shock. A capillary refill simulator would increase the realism of medical simulations and aid healthcare personnel training.

Optimally, the designed device would be a finger sleeve, however attaching Capillary_Article_Photo1the device to the palm of the hand or the sole of the foot was also acceptable. The device was required to be removable and have a lifelike appearance.  The capillary refill simulator should fit dummies ranging in size from preemie to adult; however a device that only fits dummies ranging in size from 1 to 10 years old would be acceptable.  The device must be capable of simulating capillary refill times of 0.2s-8s with skin temperatures of 92°F-105°F.   The device should have independent controls for temperature and capillary refill time. 

The group utilized their knowledge of materials, fluids, and electronics to develop a working prototype. The device is currently being reviewed by the UAB Research Foundation to establish Intellectual Property.