Heart-rate changes and gasping during intra-partum asphyxiation of a piglet. A case report.

Fetal heart rate and gasping were monitored in a chronically-catheterized fetal piglet which became asphyxiated during delivery. This piglet was the fourth to be delivered in a litter of seven. Prior to delivery of the second piglet in the litter (which was next to the affected piglet in the uterine horn), blood pH and pO(2) values were within normal limits and heart rate changes were restricted to acceleration during uterine contractions. After expulsion of the second piglet in the litter, fetal heart rate became very irregular and fetal gasping became pronounced. Terminally, periods of severe bradycardia (with gasping) which occurred late in or after uterine contractions were observed between periods when the fetal heart rate was increased. These late decelerations followed a pattern similar to those seen in asphyxiated human infants.