# A primigravida at 39 weeks gestation is in active labor. Her cervix is 6 cm dilated, 80% effaced, and the fetal head is at -1 station. The fetal heart rate shows a baseline of 140 bpm with moderate variability. Suddenly, the nurse observes a prolonged deceleration lasting 3 minutes with the fetal heart rate dropping to 80 bpm. What is the nurse's priority action?

> source: MyMerci (mymerci.kr)  
> url: https://mymerci.kr/pages/nclex_q.php?qn_id=543006  
> language: ko  
> subject: Maternal Newborn Health

## 문제

A primigravida at 39 weeks gestation is in active labor. Her cervix is 6 cm dilated, 80% effaced, and the fetal head is at -1 station. The fetal heart rate shows a baseline of 140 bpm with moderate variability. Suddenly, the nurse observes a prolonged deceleration lasting 3 minutes with the fetal heart rate dropping to 80 bpm. What is the nurse's priority action?

Emergency fetal heart rate management during active labor

## 보기

1. Document the finding and continue monitoring
2. Increase the oxytocin infusion rate to strengthen contractions
3. Change the mother's position to left lateral and administer oxygen **✔ 정답**
4. Prepare for immediate cesarean delivery

**정답: 3**

## 해설

Prolonged deceleration to 80 bpm indicates severe fetal hypoxia requiring immediate intervention. The priority is to improve fetal oxygenation by changing the mother's position to left lateral and administering oxygen. Other options are inappropriate as they delay care or worsen the situation.

## 심화 해설

Understanding the Clinical Picture

The scenario describes a prolonged deceleration, a critical finding in electronic fetal monitoring (EFM) where the fetal heart rate (FHR) drops below baseline for 2 minutes or more but less than 10 minutes. Here, the FHR dropped to 80 bpm for 3 minutes. This pattern indicates a significant disruption in fetal oxygenation, triggering a chemoreflex that shunts blood to vital organs. The priority is to immediately improve uterine blood flow and maternal oxygenation to resolve the deceleration and prevent progression to fetal hypoxic brain injury, a concern highlighted in the context of category II tracings [1].

Why the Priority Actions Work: Left Lateral Position and Oxygen

A prolonged deceleration is often caused by umbilical cord compression or uteroplacental insufficiency. The nurse's immediate non-invasive interventions directly target these mechanisms. First, changing the mother's position to left lateral displaces the gravid uterus from the inferior vena cava and aorta, instantly increasing venous return, maternal cardiac output, and uteroplacental perfusion. Second, administering oxygen via a non-rebreather mask at 10 L/min increases the maternal partial pressure of oxygen, creating a larger diffusion gradient to enhance oxygen delivery to the fetus. These actions are foundational intrauterine resuscitation techniques designed to restore fetal oxygenation before the base deficit (BDecf) deepens into severe metabolic acidemia [1].

Analyzing the Incorrect Options

Option 1 (Document and continue monitoring) is incorrect because a prolonged deceleration is a nonreassuring fetal heart rate status (NRFHRS) that demands immediate intervention, not passive observation. A systematic review confirms that NRFHRS is associated with adverse immediate outcomes, and active management is required to mitigate these risks [2].

Option 2 (Increase oxytocin infusion rate) is contraindicated and dangerous. Oxytocin increases the frequency and strength of uterine contractions, which inherently reduces intervillous space blood flow and fetal oxygenation. In the presence of a prolonged deceleration, which signals existing fetal hypoxia, stimulating contractions would further compromise the fetus. The priority is to reduce uterine activity, often by discontinuing oxytocin, not increasing it.

Option 4 (Prepare for immediate cesarean delivery) is a premature action. While a prolonged deceleration that does not resolve with conservative measures is an indication for expedited delivery, the nurse's priority is to first implement intrauterine resuscitative measures. If the FHR does not return to baseline after position change, oxygen, and other interventions, then preparation for an operative delivery becomes the next step. The evolution of intrapartum surveillance underscores that the goal of EFM interpretation is to guide timely interventions to prevent unnecessary operative deliveries while avoiding fetal harm .References (research sources)

- [1]Prevention of fetal brain injury in category II tracings.Research articleNakao M, Ross MG, Magawa S, Toyokawa S, Ichizuka K, Kanayama N, Satoh S, Tamiya N, Nakai A, Fujimori K, Maeda T, Oka A, Suzuki H, Iwashita M, Ikeda T. (2023) · DOI: 10.1111/aogs.14675

- [2]Magnitude, associated factors, and immediate outcomes of nonreassuring fetal heart rate status among laboring mothers in Ethiopia: a systematic review and meta-analysis.Meta-analysis/systematic reviewYilak G, Molla B, Tilahun BD, Abate BB, Kitaw TA, Kassie A, Getie A, Erega BB, Ayele M, Lake ES. (2026) · DOI: 10.1016/j.xagr.2026.100620

## 임상 시나리오

Clinical Practice Guide: Intrauterine Resuscitation for Prolonged Deceleration

When a prolonged deceleration is identified, the nurse must act immediately to restore fetal oxygenation and prevent metabolic acidemia. The initial steps of intrauterine resuscitation are non-invasive and can be initiated by the bedside nurse without a direct provider order in most institutional protocols.

Step 1: Maternal Repositioning

The primary goal is to maximize uterine blood flow. The left lateral position is the first-line intervention because it displaces the gravid uterus from the inferior vena cava and aorta, instantly improving maternal venous return and cardiac output. If the left lateral position does not resolve the deceleration, consider right lateral, hands-and-knees, or Trendelenburg positions to relieve potential umbilical cord compression.

Step 2: Administer Oxygen

Apply a non-rebreather face mask at 10 L/min to increase the maternal partial pressure of oxygen (PaO2). This creates a higher diffusion gradient across the placenta, maximizing oxygen delivery to the fetus. Oxygen therapy should be discontinued as soon as the fetal heart rate pattern normalizes to avoid potential fetal harm from prolonged hyperoxia.

Step 3: Address Uterine Activity

Immediately discontinue any oxytocin infusion to reduce contraction frequency and strength, which can further compromise uteroplacental perfusion. If the deceleration persists, the provider may order a tocolytic agent (e.g., terbutaline 0.25 mg subcutaneously) to temporarily relax the uterus.

Step 4: Correct Maternal Hypotension

Assess maternal blood pressure. If hypotension is present, initiate an IV fluid bolus (e.g., 500-1000 mL of Lactated Ringer's solution) as ordered to rapidly expand intravascular volume and improve placental perfusion.

Step 5: Notify the Provider and Prepare for Delivery

While initiating resuscitation, notify the obstetric provider immediately. If the prolonged deceleration does not resolve with these measures and fetal bradycardia persists, the team must prepare for an emergent cesarean delivery, as this indicates severe fetal compromise that cannot be managed conservatively.

Reference: AWHONN Fetal Heart Monitoring Program. (2022). Principles and Practices. 6th ed. Kendall Hunt.

## 핵심 개념

- **Prolonged Deceleration** — A fetal heart rate decrease of at least 15 bpm below baseline lasting 2 minutes or more but less than 10 minutes, indicating a significant disruption in fetal oxygenation.
- **Intrauterine Resuscitation** — A set of immediate interventions, including maternal repositioning, oxygen administration, and IV fluid bolus, aimed at improving fetal oxygenation during labor.
- **Left Lateral Position** — A maternal position that displaces the gravid uterus off the inferior vena cava and aorta, improving venous return, cardiac output, and uteroplacental perfusion.
- **Uteroplacental Insufficiency** — A condition where blood flow and oxygen delivery from the mother to the placenta and fetus are compromised, a common cause of non-reassuring fetal heart patterns.

## 같은 주제 문제

- [A multigravida client at 41 weeks gestation is admitted to the labor and delivery unit. Du…](https://mymerci.kr/pages/nclex_q.php?qn_id=542998)
- [A primigravida client at 38 weeks gestation is admitted to the labor and delivery unit. Du…](https://mymerci.kr/pages/nclex_q.php?qn_id=542999)
- [A primigravida client at 40 weeks gestation is admitted to the labor and delivery unit. Du…](https://mymerci.kr/pages/nclex_q.php?qn_id=543000)
- [A multigravida client at 40 weeks gestation is admitted to the labor and delivery unit. Du…](https://mymerci.kr/pages/nclex_q.php?qn_id=543001)
- [A primigravida client at 38 weeks gestation is admitted to the labor and delivery unit. Th…](https://mymerci.kr/pages/nclex_q.php?qn_id=543002)
- [A primigravida client at 39 weeks gestation is admitted to the labor and delivery unit. He…](https://mymerci.kr/pages/nclex_q.php?qn_id=543003)
- [A 32-year-old primigravida client at 38 weeks gestation is admitted to the labor and deliv…](https://mymerci.kr/pages/nclex_q.php?qn_id=543004)
- [A primigravida at 41 weeks gestation is admitted to the labor unit with strong, regular co…](https://mymerci.kr/pages/nclex_q.php?qn_id=543005)

---

More free questions: [기출문제](https://mymerci.kr/)

_학습 참고용입니다. 실제 임상은 최신 지침과 소속 기관 프로토콜을 따르세요._