Examkin

Question

Difficulty: EasyObstetric Complications

A primigravid patient is evaluated in the labor and delivery unit at 38 weeks gestation for active labor. She is currently 5 centimeters dilated and is receiving an intravenous oxytocin infusion for labor augmentation. Continuous electronic fetal monitoring displays a baseline heart rate of 145/min with moderate variability. During the observation period, the fetal heart rate tracing demonstrates recurrent, symmetric, gradual decreases in heart rate that consistently begin after the peak of the uterine contractions. The nadir of these decreases occurs after the contraction peak, and the heart rate slowly returns to baseline after the contraction has completely ended. Maternal vital signs are within normal limits. Which of the following is the most appropriate initial step in the management of this patient?

  1. Discontinuation of the oxytocin infusionAnswer
  2. B
    Proceeding to immediate cesarean delivery
  3. C
    Prophylactic amnioinfusion
  4. D
    Application of a fetal scalp electrode
  5. E
    Observation and maternal reassurance

Answer

Discontinuation of the oxytocin infusion
The clinical scenario describes recurrent late decelerations, which are visually characterized by a gradual, symmetric decrease in the fetal heart rate that begins after the peak of a uterine contraction and recovers after the contraction ends. Late decelerations are a classic sign of uteroplacental insufficiency, resulting in transient fetal hypoxemia. The primary goal of management is to improve placental perfusion via intrauterine resuscitation. The most appropriate initial steps include maternal repositioning (e.g., left lateral decubitus position to relieve aortocaval compression), administration of intravenous fluid boluses, maternal oxygen supplementation, and the immediate discontinuation of uterotonic agents such as oxytocin. Stopping oxytocin directly reduces uterine activity, thereby restoring adequate placental blood flow between contractions.

Step-by-Step Solution

1
Analyze the fetal heart rate tracing described in the stem.
The tracing shows recurrent, gradual decreases in heart rate that begin after the peak of contractions, which defines late decelerations.
Accurate interpretation of the fetal heart rate pattern is required to identify the underlying physiological stressor.
2
Correlate the deceleration pattern with its pathophysiology.
Late decelerations are indicative of transient fetal hypoxemia caused by uteroplacental insufficiency during contractions.
Understanding the cause directs the clinical intervention toward improving blood flow to the placenta.
3
Determine the first-line management for this condition.
The best initial step is intrauterine resuscitation, which includes stopping uterotonics like oxytocin.
Stopping oxytocin reduces uterine contraction frequency and intensity, allowing time for placental reperfusion and improving fetal oxygenation.

Key Concept

Recurrent late decelerations indicate uteroplacental insufficiency and should be initially managed with intrauterine resuscitation, including the discontinuation of uterotonic agents such as oxytocin.
Rate this question

Topics

Obstetric Complications

More questions from this topic