Under oxygen administration heart rate decreased from 77.6±15.7 to 75.9±14.6bpm (P=0.027).
Mean body-surface indexed stroke volumes (SVi) increased slightly but only aortic SVi change was statistically significant (pre:41.5ml/m2; post:43.6ml/m2;P=0.043). Effects
were more pronounced in pts with good Fontan circulation (HR:75.2±15.9 vs. 70.8±16.4bpm,P=0.000;
SVi(AAo):46.1±11.1 vs. 48.7±12.7ml/m2,P=0.045) than in pts with failing Fontan (HR:84.1±9.8
vs. 83.6±9.5bpm,P=n.s.;SVi(AAo):30.4±6.2 vs. 31.1±5.8ml/m2,P=n.s.). Mean absolute blood flow in Fontan patients
for AAo, IVC and SVC was 3.14±0.78, 1.84±0.52 and 0.93±0.38L/min/m2 which remained
unchanged under inhalative oxygen (3.13±0.77, 1.88±0.65 and 0.89±0.32L/min/m2).
Aortic flow rate was elevated during expiration (4.8±5.5%) and decreased during inspiration
(-2.9±8.7%) in relation to mean blood flow, highest flow was detected during inspiration
in IVC (81.1±55.3%) and SVC (18.6±30.8%) and lowest flow during expiration (IVC:-85.7±56.9%,P0.05)
and end-inspiration (SVC:-21.0±19.2%,P0.05), respectively. Differences were unchanged
under oxygen supply in AAo (4.4±5.8%,-3.4±8.6%,n.s.) and SVC (25.3±32.7%,-18.8±33.4%,n.s.),
whereas were slightly elevated in IVC (94.5±66.3%,-98.0±69.0%). Differences were only
statistically significant for end-expiratory IVC blood flow (P=0.033).