A nurse is reviewing the electronic fetal monitoring (EFM) tracing of a client in active labor.
The nurse notes that the baseline FHR is 150 bpm, with moderate variability and no decelerations.
The nurse also observes that the FHR increases by 25 bpm for 15 seconds, four times in a 20-minute period.
What term is used to describe these FHR changes?
A.
Accelerations
B.
Early decelerations
C.
Late decelerations
D.
Variable decelerations
The Correct Answer and Explanation is:
The correct answer is A. Accelerations.
Explanation:
In electronic fetal monitoring (EFM), accelerations refer to transient increases in the fetal heart rate (FHR) that occur in response to fetal movements, contractions, or other stimuli. These increases are typically defined as an increase in FHR of at least 15 beats per minute (bpm) from the baseline, lasting at least 15 seconds but less than 2 minutes. In the scenario described, the FHR increases by 25 bpm for 15 seconds, four times in a 20-minute period. This fits the definition of accelerations, as the increase in FHR is both above 15 bpm and lasts for 15 seconds or more.
Early decelerations are a type of decrease in FHR that occur simultaneously with uterine contractions. They are often a result of fetal head compression during contractions and are generally considered benign and indicative of a normal physiological response during labor. They typically mirror the contraction pattern, beginning and ending at the same time as the contraction.
Late decelerations are characterized by a decrease in FHR that begins after the onset of a contraction and returns to baseline after the contraction has ended. They are associated with uteroplacental insufficiency and can indicate a potential compromise in oxygen delivery to the fetus.
Variable decelerations are abrupt decreases in FHR that vary in duration, timing, and depth and are often caused by umbilical cord compression. They can occur randomly, independent of uterine contractions, and their appearance on the tracing can be variable.
In this case, since there is no decrease in FHR but rather an increase, and there are no decelerations of any type observed, the FHR changes described are best characterized as accelerations. These are a reassuring sign, indicating fetal well-being and an adequate response to stimuli during labor.