Trends in continuous metabolic monitoring during experimental fetal distress.
Intermittent, progressive maternal aortic occlusions were used to produce fetal distress in the fetuses of six pregnant dogs at term. Fetal heart rate and fetal tissue surface pH were continuously recorded and were compared to fetal blood pH, pCO2, pO2 and lactic acid values determined from intermittent sampling. Baseline fetal heart rate was an insensitive indicator of fetal blood pH, tissue surface pH, or of fetal blood lactic acid concentrations. "Delayed" decelerations in fetal heart rate following an occlusive episode were uniformly produced after minimal stress and also did not correlate well with these variables. On the other hand, fetal blood lactic acid concentrations remained elevated even after occlusive episodes were discontinued and other variables had returned to baseline values.
D000818:Animals; D002245:Carbon Dioxide / Q000097:blood; D004285:Dogs; D004562:Electrocardiography; D005260:Female; D005312:Fetal Blood; D005316:Fetal Distress / Q000378:metabolism / Q000503:physiopathology*; D005323:Fetal Monitoring; D006339:Heart Rate; D006863:Hydrogen-Ion Concentration; D000860:Hypoxia / Q000503:physiopathology; D007773:Lactates / Q000097:blood; D019344:Lactic Acid; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D011247:Pregnancy
D007773:Lactates; D002245:Carbon Dioxide; D019344:Lactic Acid; D010100:Oxygen