TY - JOUR
T1 - Noninvasive measurement of isovolumetric contraction time during hypoxemia and acidemia
T2 - Fetal lamb validation as an index of cardiac contractility
AU - Yumoto, Yasuo
AU - Satoh, Shoji
AU - Fujita, Yasuyuki
AU - Koga, Tsuyoshi
AU - Kinukawa, Naoko
AU - Nakano, Hitoo
N1 - Funding Information:
This study was supported by a Grant-in-Aid for Scientific Research (No. 14370322) from the Ministry of Education, Science and Culture, Japan.
PY - 2005/7
Y1 - 2005/7
N2 - Objectives: The objectives of this study are firstly to clarify how the Doppler isovolumetric contraction time (ICT) is influenced by arterial oxygen pressure (PaO2) or pH, and secondly to confirm the relationship between the Doppler ICT and myocardial contractility during hypoxemia and/or acidemia in the fetal lamb. Material and methods: In 12 pregnant ewes, fetal hypoxemia and acidemia were induced by giving ewes a variable mixture of gases for 120 min. The chronological change of fetal PaO2, pH, Doppler ICT and maximum first derivative of the left ventricular pressure waveform (Max dp/dt) was recorded every 30 min. Results: Doppler ICT and PaO2 had no significant regression. On the other hand, Doppler ICT and pH demonstrated a significant negative regression. Moreover, one critical given pH point was indicated with statistical significance at 7.20 and the prolongation of the Doppler ICT was found more markedly in the range below the pH of 7.20 compared with the range above 7.20. A significant negative linear regression was found between the Doppler ICT and the Max dp/dt. Conclusion: The measurement of Doppler ICT enables us to predict severe acidosis and a decrease of myocardial contractility in the fetus.
AB - Objectives: The objectives of this study are firstly to clarify how the Doppler isovolumetric contraction time (ICT) is influenced by arterial oxygen pressure (PaO2) or pH, and secondly to confirm the relationship between the Doppler ICT and myocardial contractility during hypoxemia and/or acidemia in the fetal lamb. Material and methods: In 12 pregnant ewes, fetal hypoxemia and acidemia were induced by giving ewes a variable mixture of gases for 120 min. The chronological change of fetal PaO2, pH, Doppler ICT and maximum first derivative of the left ventricular pressure waveform (Max dp/dt) was recorded every 30 min. Results: Doppler ICT and PaO2 had no significant regression. On the other hand, Doppler ICT and pH demonstrated a significant negative regression. Moreover, one critical given pH point was indicated with statistical significance at 7.20 and the prolongation of the Doppler ICT was found more markedly in the range below the pH of 7.20 compared with the range above 7.20. A significant negative linear regression was found between the Doppler ICT and the Max dp/dt. Conclusion: The measurement of Doppler ICT enables us to predict severe acidosis and a decrease of myocardial contractility in the fetus.
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U2 - 10.1016/j.earlhumdev.2005.04.004
DO - 10.1016/j.earlhumdev.2005.04.004
M3 - Article
C2 - 15970405
AN - SCOPUS:21844457930
SN - 0378-3782
VL - 81
SP - 635
EP - 642
JO - Early Human Development
JF - Early Human Development
IS - 7
ER -