Measurement and Control of Oxygen Saturation Levels in Neonates http://vubme.vuse.vanderbilt.edu/group13_00 Group Members Charlie Artime Kit Eward Suzanne Flanary Heather Sweeney Advisors John Penn, PhD Paul King, PhD

Background Studies published by our advisor, Dr. John Penn, and others concluded that variability in blood oxygen saturation levels, along with prolonged exposure to hypoxic conditions, increases the risk for retinopathy of prematurity.1,2,3 Penn JS, et al. “The range of PaO2 variation determines the severity of oxygen-induced retinopathy in newborn rats.” Invest. Ophthalmol. Vis. Sci. 1995 Sep;36(10):2063-70. Yoshihiro Saito, et al. “The Progression of retinopathy of prematurity and fluctuation in blood gas tension” Graefe's Archive for Clinical and Experimental Ophthalmology 1993, 231:151-156 Penn JS, et al. “Arterial Oxygen Fluctuation and Retinopathy of Prematurity in Premature Infants”

Retinopathy of Prematurity Develops in over 20% of all very low birth weight premature infants (<1500g). Characterized by abnormal blood vessel growth in the peripheral regions of the retina. Leads to detachment of the retina and, in severe cases, blindness (13% of all ROP cases). Leading cause of blindness in children.

Project Definition Team project goal: design a computer- based integrator that recommends the proper adjustment in FiO2 to avoid fluctuation in SaO2. Ultimate goal: monitor and control, with minimum variation, the blood oxygen saturation level of neonates in order to avoid development of retinopathy.

Device Specifications Pulse Oximeter Heart Rate Oxygen Saturation Level (SaO2) Integrator Amount of O2 needed to adjust inspired air (FiO2) Oxygen Blender New FiO2

IWB Diagram

How Our Device Will Help Currently, when neonates exhibit a significant change in blood oxygen saturation, adjustments to the fraction of oxygen in the inspired air must be made by hand. Typically, this results in an overshoot of the blood oxygen saturation of the neonate, and stabilization to the acceptable SaO2 range can take hours. This device can be used to help over 50,000 premature infants born each year at risk for developing ROP.

Work Completed Literature research Preliminary experimentation with the respiratory gas monitor Established liaison with NICU Worked with Innovation Workbench software Met with Dr. Lindstrom; obtained IBM laptop and Ohmeda oximeter similar to those used in the NICU. Established link between laptop and oximeter and tested data collection. Obtained last year’s SIMON data from Patrick Norris.

Current Work Making arrangements for data acquisition Dr. Penn is currently contacting Dr. Lindstrom, Dr. Walsh, and several neonatology fellows. Analyzing last year’s SIMON data. Research the relationship between pulse rate and SaO2 in infants. Tour NICU

Future Work and Timeline Task Feb. March April Collect data from NICU **** Designsafe analysis * Analyze data to determine trends ** *** Determine monitor’s sensitivity characteristics Write program to interpret data and determine necessary adjustments ********** Test and Debug

Acknowledgements Dr. Paul King and Dr. John Penn - project advisors Dr. Dan Lindstrom, Dr. Bill Walsh, and Dr. Kendall Graham -NICU Patrick Norris Dr. Richard Fries and Datex-Ohmeda