Deceleration

In obstetrics, deceleration is the term used to describe a drop in the fetal heart rate . This can be seen with cardiotocography or heard with a Pinard tube . In conjunction with the labor activity , decelerations are divided as follows:

• Dip I or early deceleration: The deceleration is the mirror image of the contraction, i. H. when the contraction is at its peak, the fetal heart rate is at its lowest and then increases again. The reason for this is a vagus stimulus , which is triggered by the pressure on the child's head in the contraction; such decelerations are harmless and indicate a healthy child. This vagus stimulus response is often described as a reactive CTG, as the fetus reacts to the contraction by decelerating.
• Dip II or late deceleration : The bottom of the deceleration is after the peak of labor. The cause of this is usually an insufficient supply of oxygen to the fetus; they are signs of an impending or imminent danger of death for the child.
• Dip 0 : A short drop in the fetal heart rate lasting less than 30 seconds.
• Variable decelerations : The deceleration is independent of the labor activity and the decelerations themselves differ in shape and duration. This can be a sign of an umbilical cord complication (e.g. entanglement ) or a premature detachment of the placenta , or it can be completely harmless. In the case of variable deceleration, it should be checked whether the heart rate shown is not a maternal signal.

literature

• Klaus Goeschen, Eckhard Koepcke (Hrsg.): Cardiotocography practice. 6th completely revised edition. Thieme, Stuttgart 2003, ISBN 3-13-591206-X .