The Study of Oxygen Therapy with Modified T - piece in Pediatric Patients after Open Heart Surgery

Choi, In Cheol; Kim, Chong Sung

Abstract

Oxygen therapy is the important method of critical care especially to pediatric patients of post-open heart surgery. The purpose of this study is to investigate the effect of oxygen therspy with modified T-piece in pediatric patients. We supply oxygen via modified T-piece after ventilatory weaning as following rates in turn : group 1; 0.05L/min/kg, group 2; 0.1L /min/kg, group 3; 0.3L/nun/kg, group 4; 0.5L/min/kg. Arterial blood gas analysis was done and heart rate, systolic and diastolic blood pressure, body temperature and oxygen sat uration were recorded. We defined absolute oxygen flow as oxygen flow/weight x weight. The relationshiop between oxygen flow/weight or absolute oxygen flow and PaO2 SaO2, was statistically significant. We got the regression equation as following : PaO2,=119.7xoxygen flow/weight+132.7 (R2=0.13), SaO2=3.2xoxygen flow/weight+97.9 (R2=0.11), PaO2=6.7Xabsolute oxygen flow+141.6 (R2=0.11), SaO2=0.16Xabsolute oxygen flow+96.2 (R2= 0.1). There were significant factors, by which PaO2, was influenced, such as oxygen flow/ weight(Pearson correlation coefficient, r=0.34), absolute oxygen flow(r=0.37), SaO2(r= 0.57), heart rate(r=-0.35), body temperature(r=0.21). As the result of mutiple regression analysis of these factors, we got the regression equation as following : PaO2=-1254.8+67.1Xoxygen flow/weight+14.5XSa0-1.6XPaCO2-0.5XheartXrate+ 2.7Xbody tempersture (R2= 0.44), PaO2=-1240+5.4Xabsolute oxygen flow+14.0XSaO2-1.4 PaCO2-0.6Xheart rate+4.0 body temperature-2.1Xweight (R2=0.46) It were group 1; 0.66, group 2; 0.69, group 3; 0.71, group 4; 0.75 that were calculated FIO2 using AaDO2 in case of FIO2=1.0 and increased significantly. However, because R2 that we got in the regression equation is too small, even though there is statistical significance, we think that clinical application of the result of our study is difficult.