Fetal transabdominal pulse oximeter studies using a hypoxic sheep model.
OBJECTIVE
This study investigates the validity of transabdominal pulse oximetry using a sheep fetal hypoxia model with fetal arterial hemoglobin saturation.


METHODS
Four pregnant ewes were anaesthetized and cannulated through the brachial artery to measure direct arterial blood saturation, SaO(2). Next, the transabdominal pulse oximeter was used to measure indirect measurement of the arterial saturation of the fetus, SpO(2), from the maternal abdomen. Hypoxia was induced by a balloon placed in the maternal aorta.


RESULTS
There is a linear relationship between SaO(2), arterial blood saturation values of the fetus, and SpO(2), the values measured by the transabdominal pulse oximetry with a slope of 0.75 (r(2)=0.76).


CONCLUSIONS
This information can be used to calibrate the transabdominal pulse oximeter as a measurement of fetal arterial saturation. With these results, we can advance the accurate, no-risk, noninvasive transabdominal fetal pulse oximeter for human use. This research may contribute to the more accurate diagnosis of the diseases of the fetus including Hypoxic Ischemic Encephalopathy.
Nioka
Shoko
S
Department of Biochem/Biophysics, University of Pennsylvania, PA 19104, USA. nioka@mail.med.upenn.edu
Izzetoglu
Meltem
M
Mawn
Theresa
T
Nijland
Michael J
MJ
Boas
David
D
Chance
Britton
B
D000005:Abdomen; D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D005315:Fetal Diseases / Q000097:blood* / Q000503:physiopathology; D005311:Fetal Hypoxia / Q000097:blood*; D007700:Kinetics; D010092:Oximetry / Q000379:methods*; D011247:Pregnancy; D012756:Sheep