title: Simultaneous measurement of fetal tissue pH and transcutaneous pO2 during labor.
abstract: Simultaneous measurement of fetal heart rate (FHR), uterine contractions (UC), continuous fetal tissue pH (TpH) and transcutaneous pO2 (tcpO2) was attempted in 40 high-risk parturients monitored for an average duration of 117 +/- 74 min. There were only two failures (9%) in the last 23 cases, with satisfactory recording of all parameters in 78% of the total. At present, the feasibility of simultaneous biochemical monitoring is limited to the active phase of labor. Fetal scalp and umbilical arterial blood pH and pO2 were obtained as well. The biochemical data showed a good correlation between tcpO2, scalp capillary pO2 and umbilical artery pO2 (P less than 0.02). The correlation was not significant between similar pH comparisons, although an average difference of 0.04 pH units was observed between the final tpH and umbilical artery pH. Both fetal TpH and tcpO2 fell progressively during labor. Preliminary findings comparing TpH, tcpO2 and FHR suggest that changes in tcpO2 rapidly reflect changing maternal and fetal conditions, while TpH responds more slowly and less sensitively.
mesh_terms: D000138:Acidosis / Q000453:epidemiology; D000328:Adult; D004566:Electrodes; D005260:Female; D005315:Fetal Diseases / Q000453:epidemiology; D005318:Fetal Heart / Q000503:physiopathology; D005311:Fetal Hypoxia / Q000453:epidemiology; D005323:Fetal Monitoring; D006339:Heart Rate; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007231:Infant, Newborn; D007743:Labor, Obstetric; D010100:Oxygen; D010313:Partial Pressure; D011247:Pregnancy; D012306:Risk
chemical_list: D010100:Oxygen