Maternity Nursing: Intrapartum Q 32
Which of the following observations indicates fetal distress?
A. Fetal scalp pH of 7.14
B. Fetal heart rate of 144 beats/minute
C. Acceleration of fetal heart rate with contractions
D. Presence of long-term variability
Correct Answer: A. Fetal scalp pH of 7.14
A fetal scalp pH below 7.25 indicates acidosis and fetal hypoxia. Fetal response to oxygen deprivation is regulated by the autonomic nervous system, mediated by parasympathetic and sympathetic mechanisms. The fetus is equipped with compensatory mechanisms for transient hypoxia during labor, but prolonged, uninterrupted fetal hypoxia may lead progressively to acidosis with cell death, tissue damage, organ failure and potentially death.
Option B: The fetal heart rate changes markedly in response to prolonged oxygen deprivation, making fetal heart rate monitoring a potentially valuable and commonly used tool for assessing fetal oxygenation status in real-time. Non-reassuring fetal heart rate patterns are observed in approximately 15% of labors
Option C: While accelerations are associated with fetal well-being, decelerations, especially prolonged bradycardia, late decelerations, and severe variable decelerations are indicative of fetal stress and should prompt the clinician to evaluate and initiate intrauterine resuscitation with consideration for delivery of the fetus as indicated.
Option D: Abnormal fetal heart rate patterns have high sensitivity, but low specificity and low predictive value to discriminate between neonates with or without metabolic acidosis. While a normal fetal heart rate pattern usually indicates reassuring fetal status, an abnormal fetal heart rate pattern does not necessarily equate with hypoxia or acidosis.