Advantages and limitations of NST
Advantages and limitations of NST ( 5 Questions)
A nurse is performing a nonstress test (NST) for a pregnant client at 32 weeks of gestation.
The nurse observes that the fetal heart rate (FHR) does not increase with fetal movement.
What factors could contribute to this result? (Select all that apply.)
Maternal medications and technical errors can contribute to a nonreactive nonstress test (NST), which means that the fetal heart rate (FHR) does not increase with fetal movement. Some medications, such as narcotics, antihypertensives, and magnesium sulfate, can affect the FHR and its variability.Â
A fetal sleep cycle usually lasts 20 to 40 minutes, and the NST can be extended or repeated if the FHR is not reactive within 20 minutes. Choice C is wrong because maternal obesity does not affect the FHR or its reactivity, but it may make it harder to obtain a clear signal from the transducer. Choice D is wrong because fetal breathing movements are a sign of fetal well-being and do not cause a nonreactive NST.
Maternal obesity does not affect the FHR or its reactivity, but it may make it harder to obtain a clear signal from the transducer.Â
Fetal breathing movements are a sign of fetal well-being and do not cause a nonreactive NST. A normal NST will show a baseline FHR between 110 and 160 beats per minute with moderate variability (5 to 25 interbeat variability) and two qualifying accelerations in 20 minutes with no decelerations. An acceleration is defined as an increase in the FHR of at least 15 beats per minute for at least 15 seconds.
Technical errors, such as poor transducer placement or loose belts, can also interfere with the accuracy of the NST.
Maternal medications and technical errors can contribute to a nonreactive nonstress test (NST), which means that the fetal heart rate (FHR) does not increase with fetal movement. Some medications, such as narcotics, antihypertensives, and magnesium sulfate, can affect the FHR and its variability. Technical errors, such as poor transducer placement or loose belts, can also interfere with the accuracy of the NST.
Choice B is wrong because a fetal sleep cycle usually lasts 20 to 40 minutes, and the NST can be extended or repeated if the FHR is not reactive within 20 minutes.
Choice C is wrong because maternal obesity does not affect the FHR or its reactivity, but it may make it harder to obtain a clear signal from the transducer.
Choice D is wrong because fetal breathing movements are a sign of fetal well-being and do not cause a nonreactive NST.
A normal NST will show a baseline FHR between 110 and 160 beats per minute with moderate variability (5 to 25 interbeat variability) and two qualifying accelerations in 20 minutes with no decelerations. An acceleration is defined as an increase in the FHR of at least 15 beats per minute for at least 15 seconds.