adjunct to the NST to elicit an acceleration of the FHR o Handheld instrument

Adjunct to the nst to elicit an acceleration of the

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adjunct to the NST to elicit an acceleration of the FHR o Handheld instrument such as an artificial larynx (esp designed for this purpose) is positioned on maternal abdomen near fetal head (leopold maneuvers are performed to determine location), & low frequency vibration & buzzing sound are emitted
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o Stimulus applied for 1-2 sec in attempt to awaken the fetus & may be repeated up to 3x w a 1- min rest period btwn attempts o Once fetal response (FHR acceleration) achieved, additional stimuli not required o Fetus that shows no response to applied stimulus may be neurologically compromised or acidotic & requires further eval - Contraction Stress Test o CST evaluates FHR response to uterine contractions o Uses electronic fetal monitor to obtain a baseline FHR tracing for 20min o If spontaneous uterine contractions do not occur during this time, uterine stimulation produced through IV oxytocin infusion(begin w 0.5mu/min & inc dose by 0.5 mu/min @15-30min intervals) or pt nipple self-stimulation until 3 contractions of at least 40sec duration occur within a 10 min time frame o CSTs evaluated according to presence or absence of late FHR decel o Late decel, associated w fetal hypoxia, is one that begins @ peak of the contraction & persists after conclusion of contraction o Episodic patterns (accel, variable decel, prolonged decel) FHR pattern do not have direct relation to uterine contractions o Test (-) if no evidence of late or significant variable decel o (+) CST is one in which there are late decelerations w 50% of contractions, even if frequency is less than 3 in 10 min o equivocal/suspicious result indicates presence of either intermittent late decels or significant (severe) variable decel o equivocal/hyperstimulatory result indicates presence of 1 of following: late decels occurring w uterine contractions that are more frequent than 5 contractions in 10 min, late decels occurring w uterine contractions that are more frequent than every 2 min, or late decel occurring w uterine contractions lasting longer than 90 sec o unsatisfactory or equivocal/unsatisfactory result occurs when there are fewer than 3 uterine contractions within a 10 min period or when a poor quality FHR data tracing occurs that is perceived as uninterpretable or intermediate o Bc CST based on presence of uterine contractions – several contraindications to the test Pts who have experienced 3 rd trimester bleed from placenta previa or marginal abruptio placentae, W who have had extensive uterine surgery (including classic c/s), those @ high risk for PTL, & those w PROM not candidates for CST - Electronic FHR monitoring o Use electronic techniques to give ongoing assessment of fetal well-being o EFM provides info r/t the response of the FHR in presence or absence of uterine contractions o Electronic monitoring of FHR can be accomplished either internal or external SPECIAL CONDITIONS AND CIRCUMSTANCES THAT MAY COMPLICATE PREGNANCY - The Pregnant Woman Who Requires Bedrest o Muscle wasting, bone loss, failure to gain weight, & CV & psychological difficulties o
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