Physiological Integrity Q 23
A vaginal exam reveals that the cervix is 4cm dilated, with intact membranes and a fetal heart tone rate of 160–170 bpm. The nurse decides to apply an external fetal monitor. The rationale for this implementation is:
A. The cervix is closed.
B. The membranes are still intact.
C. The fetal heart tones are within normal limits.
D. The contractions are intense enough for insertion of an internal monitor.
Correct Answer: B. The membranes are still intact.
The nurse decides to apply an external monitor because the membranes are intact. The test is used to determine if a fetus is at risk for intrauterine death or neonatal complications, usually secondary to high-risk pregnancies or suspected fetal hypoxemia. The frequency of use is based on clinical judgment, but is common because it is non-invasive and presents a low maternal and fetal risk; however, the test does not hold predictive value and only indicates fetal hypoxia at time of the test.
Option A: The cervix is dilated enough to use an internal monitor, if necessary. Fetal heart rate is monitored using the Doppler ultrasound transducer, and the tocodynamometer is applied to detect uterine contractions or fetal movement. Fetal activity may be recorded by the patient using an event marker or noted by the staff performing the test.
Option C: An internal monitor can be applied if the client is at 0-station. The Non-Stress Test (NST) is an assessment tool used from 32 weeks of gestation to term to evaluate fetal health through the use of electronic fetal monitors that continuously record the fetal heart rate (FHR). The test is used to determine if a fetus is at risk for intrauterine death or neonatal complications, usually secondary to high-risk pregnancies or suspected fetal hypoxemia.
Option D: Contraction intensity has no bearing on the application of the fetal monitor. The NST involves 20 minutes of monitoring the FHR while assessing the number, amplitude, and duration of accelerations that usually correlate with fetal movement. A normal test result, as defined by the American College of Obstetrics and Gynecologist, is one in which two or more accelerations peak at 15 bpm or more above baseline, each lasting 15 seconds or more, and all occurring within 20 minutes of beginning the test.