Term
What are the 5 factors for adequate fetal oxygenation? |
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Definition
Placental blood flow Maternal 02 saturation Exchange of O2 and CO2 in placenta Vessels in umbilical cord Fetal circulatory & O2 carrying functions |
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Term
How does O2 get to the fetus? |
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Definition
O2 & nutrients in maternal blood pass into the fetal blood via the intervillous spaces of the placenta via the spinal arteries. |
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Term
How are waste products removed from the fetus? |
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Definition
Maternal blood carrying fetal waste products drains from the intervillous spaces through endometrial veins and returns to the mom’s circulation for elimination from her body |
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Term
What happens to the uteroplacental arteries during labor when contractions are occurring? |
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Definition
Contractions gradually compress the uteroplacental arteries, temporarily stopping maternal blood flow into the intervillous spaces.
During UCs, the fetus depends on oxygen supply already present in body cells, fetal RBCs, and intervillous spaces. |
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Term
What happens when contractions stop? |
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Definition
As the contraction relaxes, freshly oxygenated maternal blood re-enters the intervillous spaces and waste-laden blood drains out. 1-2 minutes |
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Term
What is fetal circulation? |
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Definition
The umbilical vein carries oxygenated blood to the fetus. Two umbilical ateries carry deoxygenated blood from the fetus to the placenta
opposite of adult!!! |
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Term
What are the 3 shunts in fetuses? |
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Definition
the ductus venosus, the ductus arteriosus, and the foramen ovale—allow most blood from the placenta to bypass the fetal lungs and liver. |
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Term
What regulates fetal heart rate? |
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Definition
Autonomic nervous system: Parasympathetic: decreases heart rate Sympathetic: increases heart rate Baroreceptors Chemoreceptors Adrenal Glands CNS Causes HR to increase with fetal movement Causes HR to decrease when fetus sleeps |
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Term
How do barorecptors affect FHR? |
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Definition
cells in the carotid arch and major arteries respond to stretching when the fetal BP increases. The baroreceptors stimulate the vagus nerve to slow the FHR and decrease BP. As fetal BP falls, the HR accelerates to maintain normal CO2. |
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Term
How do chemoreceptors affect FHR? |
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Definition
Cells that respond to changes in oxygen, CO2, and pH are found in the medulla oblongta and in the aortic and carotid bodies. Decreased O2 content, increased CO2 or lower pH in the blood triggers an increase in HR. Prolonged hypoxia, hypercapnia, and acidosis depress the FHR. |
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Term
How do adrenal glands affect FHR? |
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Definition
secrete epinephrine and norepinephrine in response to stress, causing the sympathetic NS to accelerate the FHR. |
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Term
How does the CNS effect FHR? |
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Definition
The fetal cerebral cortex causes the HR to increase during fetal movement and to decrease when the fetus sleeps. Cerebral cortex (↑HR w/fetal movement & ↓HR w/fetal sleep) Hypothalamus (coordinates ANS) Medulla (maintains balance between stimuli that speed and stimuli that slow the HR) |
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Term
What are the maternal pathologic influences on fetal oxygenation? |
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Definition
Cardiopulmonary alterations Uterine Activity Placental Cord |
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Term
What does maternal HTN cause? |
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Definition
Maternal HTN→vasospasm and narrowing of the spiral arteries causes decreased blood flow to the placenta i.e. the patient w/HTN who might need to be delivered early…placenta may start to infarct d/t ↓flow |
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Term
What does maternal blood volume loss cause? |
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Definition
Blood volume=Hemorrhage or Altered distribution of blood volume without loss… For example, epidural causes generalized maternal vasodilation which causes hypotension which causes decreased blood flow to the placenta CHANGES IN BP, OXYGENATION, ACID BASE, ASTHMA, SMOKING |
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Term
How does uterine activity effect the fetus? |
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Definition
HYPERTONIC ACTIVITY: over 90-120 sec or too frequent (closer than q 2 min) or too short of an interval (less than 30 sec relaxation) remember what happens to the intervillous spaces during UCs and the amount of o2 reserve (1-2 min) |
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Term
How does placental activity affect the fetus? |
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Definition
Open circulation paths…abruptio placentae (DESCRIBE WHAT IT IS-JESSICA STORY) INFARCTS: Amount and location of disruption relates to the degree of impairment of uteroplacental exch |
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Term
How does the cord effect the fetus? |
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Definition
Interruptions in umbilical flow or OLIOGHYDRAMNIOS: may not be enough fluid to cushion the cord. |
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Term
What are the fetal pathologic influences on fetal oxygenation? |
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Definition
Low fetal blood volume Fetal anemia Fetal hypotension Prolonged bradycardia Prolonged tachycardia |
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Term
How does low fetal blood volume effect oxygenation? |
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Definition
May be hypoxic despite adequate oxygen supply from Mom and adequate exchange in the placenta LOW FETAL BLOOD VOLUME, FETAL HYPOTENSION, FETAL ANEMIA |
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Term
How does fetal CNS abnormalities effect? |
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Definition
CNS or Cardiac abnormalities: may cause abnormal rate and rhythm |
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Term
How does prolonged bradiacardia effect the fetus? |
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Definition
both a response to hypoxia and causes hypoxia/OXYGENATION IS RATE-DEPEND |
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Term
How does prolonged tachy effect the fetus? |
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Definition
decreases CO-ventricles have less time to fill with oxygenated blood |
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Term
What is electronic fetal monitoring? |
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Definition
Method of assessing fetal status both before and during labor. Indicator of uteroplacental physiology and fetal oxygenation. |
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Term
What are the 2 modes of fetal monitoring? |
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Definition
be external or internal 2 modes for external monitoring Intermittent/Continuous |
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Term
What other data should fetal monitoring be used with? |
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Definition
Maternal/fetal risk factors Stage of labor/etc. |
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Term
What is the nurses responsibility? |
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Definition
assess FHR patterns, implement nursing interventions, and report non-reassuring patterns to primary care provider |
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Term
What is intermittent monitoring? |
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Definition
Perform Leopold’s maneuvers Auscultate using Doppler Palpate abdomen at fundus to assess uterine contractions Count FHR 30-60 sec for baseline Auscultate FHT during contraction and for 30 sec after end of ctx Identify any non-reassuring patterns and notify provider |
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Term
What are the advantages of external fetal monitoring? |
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Definition
Noninvasive/reduces infection Membranes may be intact Cervix does not have to be dilated Placement can be performed by nurse Records permanent record of FHR tracing |
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Term
What are the disadvantages of external fetal monitoring? |
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Definition
Contraction intensity is NOT measurable Patient movement requires repositioning of transducers Obesity and fetal position affect quality of tracing |
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Term
What are the advantages to auscultation monitoring? |
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Definition
mobility, water-based methods of pain mgmt (whirlpool, tub), more NATURAL |
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Term
What are the disadvantages of auscultation monitoring? |
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Definition
FHR & UCs assessed for only portions of labor, no continuous printed record is available to show fetal response throughout labor or to identify subtle trends in the response. Some women don’t like the interruptions of auscultation: distracting More staff-intensive than EFM |
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Term
What are the advantages of continuous monitoring? |
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Definition
Supplies more data about the fetus: early, late, variable decels; variability; Permanent record Gradual trends in FHR and uterine activity are more apparent Women may find constant sound of FHR soothing and comforting The coach can use the tracing to anticipate UCs Allows one nurse to monitor 2 laboring women; allows time for other interventions like teaching. |
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Term
What are the disadvantages of continuous monitoring? |
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Definition
Reduced mobility Frequent adjustment of equipment Belts, monitors may be uncomfortable Woman may concentrate on making a good tracing vs. comfort Technical rather than natural |
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Term
When do you externally monitoring a low risk woman in the latent phase? |
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Definition
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Term
When do you externally monitor a high risk woman in the latent phase? |
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Definition
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Term
When do you externally monitor a low risk woman in the active phase? |
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Definition
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Term
When do you externally monitor a high risk woman in the active phase? |
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Definition
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Term
When do you monitor a low risk woman in the second stage of labor? |
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Definition
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Term
When do you monitor a high risk woman in the 2nd stage of labor? |
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Definition
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Term
WHen is routine monitoring done? |
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Definition
Rupture of membranes Before and after ambulation Before and after medication administration Peak action of anesthesia Following vaginal exam Following expulsion of enema After urinary catheterization Following period of abnormal/excessive ctx’s |
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Term
What are the 2 external monitoring systems? |
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Definition
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Term
What are the 2 internal monitoring systems? |
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Definition
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Term
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Definition
Fetal scalp electrode and intrauterine pressure catheter. A, Parts of the fetal scalp electrode before it is applied. B, Fetal scalp electrode and intrauterine pressure catheter in place and connected to the bedside monitor unit. |
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Term
How do you assess tracings for fetal heart tones? |
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Definition
Baseline (#1) Variability (#2) Periodic changes (#3) |
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Term
How do you assess for contraction pattern? |
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Definition
Frequency, duration, strength MUST PALPATE FOR STRENGTH |
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Term
What is the upper grid for? |
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Definition
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Term
What is the lower grid for? |
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Definition
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Term
What are the indications of continuous fetal monitoring? |
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Definition
Multiple gestations Placenta previa Oxytocin (Pitocin) infusion Fetal bradycardia/tachycardia Maternal complications: Diabetes, Pregnancy HTN Intrauterine growth restriction (IUGR) Post dates Meconium-stained fluid Abruption placenta (suspected or actual) Abnormal nonstress test Abnormal uterine contractions Fetal distress Facility/provider preference |
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Term
What maternal history calls for continuous monitoring? |
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Definition
Prior stillbirth, Prior C/S, Poor nutrition, Chronic diseases, Acute infections, Hematologic problems |
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Term
What antepartum conditions calls for continuous monitoring? |
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Definition
HTN, PIH, DM, CV disease, Sickle cell, preterm, Post-term >42 weeks, Multiples, IUGR, Maternal age ↓fetal movement, Placental abnormalities, Severe anemia, Maternal trauma, Maternal infection |
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Term
What intrapartum conditions call for contunous monitoring? |
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Definition
Maternal Problems: PROM, Prolong ROM, Hypotension or hypertension, Hypertonic Ucs, Failure To Progress (FTP), Chorioamnionitis, Fever, Bleeding ,Pitocin, PTL, CPD, VBAC Fetal or Placental Problems: Fetal anemia, Abnormal FHR or pattern, Meconium-stained amniotic fluid Abnormal presentation or position, Prolapsed cord, Abruptio placentae |
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Term
What factors effect the apparent intensity of the strip? |
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Definition
1.Fetal size: small fetus doesn’t allow the uterus to push firmly against the abdominal wall w/each UC, making contractions appear less intense. 2. Abdominal fat thickness: thicker layer absorbs energy from UCs while thin woman may appear to have intense contractions that are actually mild. 3. Maternal position: different maternal positions may increase or decrease pressure against the toco 4. Location of the transducer: uterine activity is best detected where it’s strongest and where the fetus lies close to the uterine wall= upper uterus=fundus Internal IUPC- must be 2-3 cm dilated |
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Term
What does the internal uterine monitoring system show? |
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Definition
Frequency Duration Intensity Resting Tone |
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Term
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Definition
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Term
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Definition
Less than 120 bpm for 10 mins or longer |
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Term
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Definition
More than 160 bpm for 10 mins or longer |
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Term
How is variability scored? |
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Definition
Absent Minimal Moderate Marked |
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Term
When is baseline FHR assessed? |
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Definition
between contractions with no fetal movement noted |
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Term
Over how many minutes is the FHR taken? |
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Definition
Over 2 mins
Rounded up to 5 bpm Example: 125, 140, 135 Excludes temporary increases or decreases |
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Term
What causes fetal bradycardia? |
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Definition
Uteroplacental insufficiency Umbilical cord prolapse Maternal hypotension Prolonged cord compression Fetal congenital heart block Anesthetic medications |
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Term
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Definition
Maternal infection Maternal dehydration Maternal cocaine or meth use Fetal anemia Fetal heart failure Fetal cardiac dysrhythmia |
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Term
What are the nursing interventions for fetal brady? |
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Definition
Notify provider Stop oxytocin Left side Administer O2 Start IV Administer tocolytic Terbutaline Scalp stimulate |
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Term
What are the nursing interventions for fetal tacky? |
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Definition
If fever, antipyretics Administer O2 Bolus IV fluids |
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Term
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Definition
Fluctuations in baseline FHR: the normal irregularity of the FHR |
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Term
What does variability result from? |
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Definition
Results from a continuous balancing of the sympathetic (cardioacceleration) and the parasympathetic (cardiodeceleration) branches of the ANS. |
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Term
What is variability an indicator of? |
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Definition
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Term
What does variability reflect? |
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Definition
Reflects neurological modulation of the FHR |
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Term
What is the amplitude range of absent variability? |
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Definition
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Term
What is the amptitude range of minimal variability? |
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Definition
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Term
What is the amplitude of moderate variability? |
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Definition
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Term
What is the amplitude of marked variability? |
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Definition
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Term
What is long term variability? |
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Definition
Rhythmical and cyclical fluctuations Interpretation of LTV is made by visual examination of the rise and fall and frequency of changes in FHR within the baseline range. Assessed w/either external or internal monitors It’s the zigzag you see in the FHR line |
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Term
What is short term variability? |
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Definition
Changes in FHR from one beat to the next (beat-to-beat) Internal scalp electrode is only method to accurately measure STV Presence of STV indicates the fetus is appropriately responding to nerve impulses and has an intact ANS Indicator of fetal oxygenation and oxygen reserve in the tissue |
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Term
What are the causes of decreased variability? |
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Definition
Medications that depress the CNS Narcotics, barbiturates, tranquilizers, general anesthetics Fetal hypoxemia with resulting acidosis Fetal sleep cycle Congenital anomalies |
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Term
What are the nursing interventions r/t decreased variability? |
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Definition
Position patient to left lateral position Stimulate the fetal scalp Assist provider with scalp electrode or fetal blood PH sampling |
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Term
T or F? VARIABILITY YOU SEE EXTERNALLY WILL OFTEN BE LESS INTERNALLY |
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Definition
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Term
What causes increased variability? |
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Definition
Mild hypoxia Fetal stimulation |
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Term
What causes decreased variability/ |
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Definition
Extreme prematurity Arrhythmias Hypoxia Acidosis Drugs Fetal sleep |
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Term
What are periodic changes? |
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Definition
Temporary, recurrent changes from baseline that are associated with uterine contractions |
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Term
What are the types of decels? |
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Definition
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Term
What is the most common periodic change in the fhr? |
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Definition
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Term
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Definition
Increase in FHR of > 15 BPM above baseline lasting 15 seconds-2minutes |
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Term
What is an acceleration a sign of? |
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Definition
Not a sign of distress Reassuring symptom of fetal well being. Indicates intact CNS system Normal response Indicates REACTIVE NON-STRESS TEST |
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Term
When do early decels occur? |
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Definition
only during contractions as the fetal head is compressed |
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Term
When do early decels end? |
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Definition
Return to the baseline fetal heart rate by the end of the contraction |
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Term
What are early decels mirror images of? |
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Definition
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Term
Are early decels associated with fetal compromise? |
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Definition
NO
HEAD COMPRESSION-vagal stimulation Requires no additional interventions |
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Term
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Definition
Reflect impaired placental exchange or uteroplacental insufficiency Another cause: maternal hypertension |
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Term
What are the characteristics of late decesl? |
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Definition
Look similar to early decels Begin well after the contraction begins (often near the peak of contraction) FHR returns to baseline after the contraction ends THEY ARE “LATE” TO RETURN TO BASELINE! |
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Term
What nursing intervention is there r/t late decelerations? |
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Definition
Require nursing intervention to improve placental blood flow and fetal oxygen supply
Position on left side! Discontinue Oxytocin if infusing Administer O2 at 8-10L/min via face mask Start an IV if not in place or IV rate Notify provider of care Prepare for assisted vaginal birth or C/S |
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Term
What causes a variable deceleration? |
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Definition
Umbilical cord compression Also: Short cord, Prolapsed cord, Nuchal cord (cord around neck), Oligohydramnios |
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Term
What are the characteristics of a variable deceleration? |
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Definition
The shape, duration, and degree of fall below baseline rate are variable: V, U, W shaped The fall and rise in rate is abrupt May be nonperiodic =not associated with UCs |
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Term
When do variable decelerations occur? |
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Definition
After rupture of membranes |
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Term
What is the nursing intervention r/t variable decelerations? |
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Definition
#1-Change position (any position!) Discontinue Oxytocin if infused Administer 8-10 L/min per mask Perform or assist with vaginal exam Assist with amnioinfusion if ordered |
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Term
What causes variable decels? |
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Definition
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Term
What causes early dccels? |
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Definition
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Term
What causes accelerations? |
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Definition
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Term
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Definition
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Term
What are non reassuring patterns? |
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Definition
Tachycardia Bradycardia Decreased or absent variability Late decelerations Variable decelerations Below 70 bpm for longer than 60 sec. indicates a nonreassuring pattern Prolonged decelerations Hypertonic uterine activity |
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Term
What are the main things to remember with fetal monitoring? |
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Definition
Identify the cause of the pattern Evaluate for probable cause Evaluate maternal vital signs Identify prolapsed umbilical cord Stop oxytocin (Pitocin) infusion Reposition woman – R or L side |
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Term
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Definition
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Term
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Definition
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Term
What interventions should you do with nonreassurring fetal heart rate? |
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Definition
Increase rate of infusion of a nonadditive intravenous fluid Administer oxygen by face mask at 8 to 10 L/min Initiate continuous electronic fetal monitoring (if not already in place) Notify physician or nurse-midwife Prepare for immediate delivery, if necessary |
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Term
What is fetal scalp stimulation? |
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Definition
Fetal scalp stimulation identifies fetal response to gentle massage. An acceleration in the fetal heart rate of 15 beats per minute for 15 seconds suggests that the fetus is in normal oxygen and acid-base balance. Accelerations often occur with vaginal examination unrelated to nonreassuring fetal heart rate patterns. |
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Term
What is vibroacoustic stimulation? |
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Definition
the application of a vibratory sound stimulus to the abdomen of a pregnant woman to induce FHR accelerations. |
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Term
Where does the fetal o2 monitor work? |
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Definition
special sensor places near fetal cheek or temple O2 sat of 30-70% normal because of high HCT/HGB Critical for use: single fetus/36 wks/vertex/nonreassuring FHR/ruptured/2cm/-2 station Critical Threshold=less than 30% Technical issues (faint/debris) |
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Term
What is fetal scalp blood sampling? |
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Definition
Ph < 7.2= acidosis Requirements ROM Cervix 3cm Used to verify FHR pattern |
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Term
When is cord blood gases and pH done? |
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Definition
After birth not during labor |
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Term
What is the nursing interventions r/t mother's during non reassuring patterns |
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Definition
Identify potential candidates/Assist/Provide comfort and reassurance/communicate and document findings and interventions |
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Term
What is a cord blood gas test? |
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Definition
Obtaining a blood sample to determine umbilical cord blood gas values and pH. Samples are drawn from the umbilical artery and vein. Arterial samples most closely reflect fetal oxygen and acid-base status. The samples in capped syringes may be kept for up to 60 minutes at room temperature. |
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Term
When should you document? |
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Definition
Every 15 min during 1st Stage Every 5 min during 2nd Stage Before and after procedures With changes in activity |
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