Maternal hyperventilation as a possible cause of fetal tachycardia sub partu. A clinical and experimental study.
Examination of 28 agitated, hyperventilating patients with fetal tachycardia showed that the mothers were in a hyperventilation-related state of hypocapnia and alkalosis. The mean maternal pCO2 was 17.48 +/- 6.79 mm Hg, the pH 7.54 +/- 0.14, which caused a reflex spasm of the umbilical veins, fetal acidosis and fetal tachycardia. Additional experiments on sheep revealed a similar correlation between maternal hyperventilation, hypocapnia, respiratory alkalosis and fetal tachycardia while the flow volume of the uterus showed no change.
D000472:Alkalosis, Respiratory / Q000097:blood / Q000503:physiopathology; D000818:Animals; D002245:Carbon Dioxide / Q000097:blood; D005260:Female; D005312:Fetal Blood / Q000032:analysis; D005315:Fetal Diseases / Q000097:blood / Q000209:etiology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006985:Hyperventilation / Q000097:blood / Q000503:physiopathology*; D007231:Infant, Newborn; D007744:Obstetric Labor Complications / Q000097:blood / Q000503:physiopathology; D011247:Pregnancy; D051381:Rats; D012756:Sheep; D013610:Tachycardia / Q000097:blood / Q000209:etiology*
D002245:Carbon Dioxide