Richard Taylor started working in Professor George’s lab in Spring, 2008, which he describes as the opportunity to work “on an innovative approach to diagnosing asthma, on a team bringing their unique talents and experiences together to solve a common problem.” He found it particularly rewarding to be able to contribute practical results to a problem that is so widespread and poorly understood. Upon graduating from UCI, Richard hopes to make a career of research, pursuing a Ph.D., and eventually working and teaching at a research institution.

Nitric oxide (NO) is present in exhaled breath after being produced by cells throughout the lungs. NO is affiliated with inflammation, including pulmonary inflammatory diseases such as asthma. The widespread and growing presence of asthma highlights the need for improved diagnosis and treatment methodologies; the affiliation between NO and inflammation gives rise to the possibility that NO measurements could be used as a clinical tool in the diagnosis and treatment of inflammatory pulmonary disease. As one step toward this goal, this study sought to discover the most reliable interval of the exhaled NO signal for analysis. Exhaled NO measurements of 51 patients aged 7–16 years with mild to moderate asthma were collected at the Breathmobile operated by the Children’s Hospital of Orange County. Exhaled volume was measured relative to each subject’s airway volume and collected at flows of 50, 100, and 200 ml/s. The volume of exhaled breath was normalized relative to the volume of the airway tree. The data shows that the clearest and most reliable interval of the exhaled breath on which to measure nitric oxide is from four to six airway volumes. This information will enable more reliable use of exhaled nitric oxide, ultimately enabling more accurate asthma diagnosis and treatment decisions for the pediatric population.

Steven C. George Henry Samueli School of Engineering

Exhaled nitric oxide (eNO) is elevated in asthmatics and is a purported marker of airway inflammation. By measuring eNO at multiple flows and applying models of eNO exchange dynamics, the signal can be partitioned into its proximal airway [J’awNO (nl/s)] and distal airway/alveolar contributions [CANO (ppb)]. Several studies have demonstrated the potential significance of such an approach in children with asthma. However, techniques to partition eNO are variable, limiting comparisons among studies. This project demonstrates that when using the multiple flow technique to partition eNO, the method of analysis (constant time versus constant volume interval) significantly affects the estimation of CANO, and thus potentially the assessment and interpretation of distal lung inflammation.