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Zorluk: OrtaObstetric Complications

A nulliparous woman presents to the labor unit at 40 weeks and 2 days of gestation reporting regular uterine contractions. She is 24 years old and has had an uncomplicated pregnancy. On initial assessment, her cervix is dilated to 5 cm and completely effaced, with the fetal vertex at 0 station. Over the next hour, her contractions occur every 3 minutes. The continuous fetal monitor displays a baseline heart rate of 130/min with moderate variability. However, there are recurrent, abrupt decreases in the fetal heart rate to 80/min that reach their nadir within 15 seconds. These episodes last approximately 45 seconds and occur concurrently with the majority of the contractions before rapidly returning to baseline. The nursing staff assists the patient in changing to the left lateral decubitus position and administers an intravenous normal saline bolus, but the fetal heart rate pattern does not change. A subsequent cervical examination reveals no palpable umbilical cord.

Which of the following is the most appropriate next step in the management of this patient?

  1. A
    Proceed immediately to cesarean delivery
  2. B
    Administer intravenous terbutaline
  3. Perform an amnioinfusionCevap
  4. D
    Reassure the patient and continue observation
  5. E
    Perform an operative vaginal delivery

Cevap

Perform an amnioinfusion
The correct answer is performing an amnioinfusion. This patient is experiencing recurrent variable decelerations, defined by abrupt decreases in the fetal heart rate (onset to nadir less than 30 seconds). Variable decelerations are caused by transient umbilical cord compression. When they become recurrent (occurring with at least half of the contractions) and do not respond to initial resuscitative measures such as maternal repositioning and intravenous fluid boluses, an amnioinfusion is the most appropriate next step. Amnioinfusion involves instilling normal saline into the uterine cavity to artificially restore amniotic fluid volume, which cushions the umbilical cord, often resolving the decelerations and preventing fetal acidemia.

Adım Adım Çözüm

1
Analyze the fetal heart rate (FHR) tracing characteristics.
The tracing shows an abrupt decrease (onset to nadir < 30 seconds) in FHR, with a nadir of 80/min lasting 45 seconds, associated with contractions.
Identifying the specific type of deceleration (variable, early, or late) is required to determine the underlying pathophysiology.
2
Correlate the FHR pattern with its underlying etiology.
Abrupt FHR decreases represent variable decelerations, which are caused by umbilical cord compression.
Variable decelerations are typically reflex responses to transient cord compression during contractions.
3
Evaluate the response to initial intrauterine resuscitation.
Maternal repositioning and intravenous fluid administration failed to resolve the recurrent variable decelerations, and there is no overt cord prolapse on exam.
Initial management aims to alleviate cord compression mechanically and improve uteroplacental perfusion, but persistent decelerations require escalated intervention.
4
Select the most appropriate definitive next step.
Amnioinfusion is the appropriate step to artificially increase amniotic fluid volume and cushion the umbilical cord.
When initial measures fail, amnioinfusion can effectively relieve cord compression in the first stage of labor, often preventing the need for surgical delivery.

Anahtar Kavram

Amnioinfusion is indicated for recurrent variable decelerations that do not resolve with initial resuscitative measures (e.g., maternal repositioning, fluid bolus) to relieve umbilical cord compression and prevent fetal acidemia.
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Obstetric Complications

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