1 AWHONN Fetal Heart monitoring basics

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Helps Assess Fetal Well-Being Can Use external Doppler US Device or Internal Fetal Scalp Electrode Should Be Monitored Every 30 Minutes in Stage I, Every 15 Minutes in Stage 2

Fetal Heart Rate Monitoring (two methods)

Uses sonar to track the fetal myocardium & converts movement into sound. If placed incorrectly may pick up maternal heart. Perform Leopold's maneuvers to find fetal back, locate heartbeat, count FHR, check mothers pulse and compare.

Handheld Fetal Doppler

Similar to toco tracings, contractions are in (mm HG) and appear as elevations from the baseline resting tone and are quantified measures of contractions intensity and resting tone. Normal baseline tone is 5-20 mmHg Mild contractions w/ peak of <40 mm Hg Moderate contractions w/ peak of 40-70 mm Hg Strong contractions w/ peak of >70 mm Hg

How are IUPC tracings displayed, what are normal values?

ID risk factors such as HTN (=vasoconstriction), Maternal smoking, abruption, post-term pregnancy, maternal diabetes and consider FHR characteristics

How can you determine if the placenta is functioning optimally?

Change the mother's position to her side, sitting up, on hands and knees, or a combination of position to maximize umbilical circulation.

How do you alleviate umbilical cord compression?

Fetal heart rate patterns 5 characteristics 1 Baseline heart rate 2 Rhythm 3 FHR variability 4 Presence of accelerations 5 Periodic or episodic deceleration's

How do you determine fetal oxygenation? Name the 5 characteristics

Using your fingertips at the fundus you can assess duration and frequency. Intensity: nose= mild chin=moderate forehead=strong

How do you palpate a contraction? Describe the intensities.

vaginal exam

How do you rule out cord prolapse?

Used to measure uterine contractions it is inserted via sterile introducer tube placed within the cervix next to the presenting part. The catheter itself is flexible is inserted into the uterus. Insertion is complete when the mark on the catheter is just visible at the introitus.

How is an IUPC intrauterine pressure catheter placed?

This depends on oxygenation which is reflected in FHR variability and accelerations on the fetal monitor tracings.

How many uterine contractions can be tolerated?

500-700ml to the uterus per minute, 80% is directed to the placenta

How much blood normally flows to the placenta?

ACOG says if no risk factors on admission Q30min in 1st stage then Q15min in 2nd stage active pushing of labor If on oxytocin or risk factors then Q15 in 1st stage then Q5 in 2nd stage active pushing of labor

How often should I assess the FHR when using electronic monitoring?

Interventions may include administering a tocolytic to decrease uterine activity if tachysystole or elevated resting tone are present. Admin. Oxygen at 10 L/min by non rebreather and notify MD

What actions would you take for late decels that are recurrent and occur with minimal or absent FHR variability?

true

True or False A preterm fetus my be more susceptible to hypoxemia

true

True or False The nervous system is not fully developed in fetuses prior to 32 wks gest.

Minimal- Small fluctuations in the FHR, detectable but not more than 5 BPM

What is the variability?

Moderate-note the span of the fluctuations in the baseline FHR. They are 10-20 BPM in height. The range of moderate variability is 6-20 BPM

What is the variability?

The response of the FHR to a vibroacoustic stimulus. An acceleration on NST (> 15 bpm for > 15 sec) is a positive result. An acceleration in response is an indicator of fetal oxygenation. Useful adjunct to decrease the time to achieve a "reactive" NST (R-NST) and to decrease the proportion of non-reactive NST at term, precluding the need for further testing.

What is vibroacoustic stimulation?

top center is where you should receive the most accurate reading of uterine contractions as term.

Select the best location for placement of Toco for a term pregnancy.

Uterus

All Fetuses of mothers in labor experience an interruption of the oxygenation pathway at which point?

Assess baseline FHR Determine rhythms (regular vs irregular) ID accelerations and deceleration's but not the type of deceleration (early/late/variable) The fetal heartbeat is best heard over the fetal back.

Auscultation of Fetal Heart Sounds tell you what information? Where is the best place to listen?

30-50% lateral recumbent or semi-Fowler's

By what % does maternal cardiac output increase above the non-pregnant state and what position helps this uteroplacental blood flow?

Visually apparent decreases of the fetal heart rate below baseline. A gradual decrease is if there are 30 sec. or more from onset of decel to the nadir (deepest point) An abrupt decrease is if there are less than 30 sec. from onset of decel to the nadir (deepest point)

Define fetal heart rate decelerations.

Visually apparent, usually symmetrical, gradual decrease (>30 seconds from onset to nadir), and return of the FHR associated with a contraction. The nadir is typically coincident with the peak of the contractions, giving a mirror image appearance. They begin early in the contraction, reach their lowest point at the peak of the contraction and return to baseline at the end of the contraction. Usually due to pressure on the fetal head from contractions. They cause changes in intracranial pressure and cerebral blood flow, which stimulates the vagus nerve. They are a normal reflex response.

Define early deceleration

Likely the cause of late decels is tachysystole. Tachysystole interrupts blood flow which can result in fetal hypoxemia. The lack of oxygen availability has led to slowing of the FHR. Contractions are so close in timing that Fetal heart is unable to recover as normally would. 3 Goals to achieve through assessment and interventions: reduce uterine activity max uterine blood flow max oxygenation SO: notify MD, DC oxytocin, change position, admin IV fluid bolus, admin oxygen by non-rebreather mask 10L/min

Case study #1 First pregnancy. Contractions every 7 min lasting 40 seconds, moderate by palpation, pain rated 4/10. Vaginal exam shows 4cm dilated, 100% effaced and -1 station. However no change in the last 3 hours. Oxytocin was ordered to augment, an FSE & IUPC was placed. 2hrs after oxytocin started this is the tracing. Contractions q 1.5 min, lasting 60-70 seconds, 55-60 mmHg. Resting tone btwn contractions is 25 mmHg. Baseline FHR 155 BPM w minimal variability. A pattern of late decelerations is emerging. You should be able to see relationship btwn uterine activity pattern & FHR tracing characteristics.

Category I Shows normal FHR baseline, moderate variability, and accelerations. Normal baseline, moderate variability, accelerations, and decelerations absent meet criteria for Category I tracing.

Classify and explain the tracing as I, II or III.

Category III Shows tachycardia, recurrent late decelerations and absent variability.

Classify and explain this tracings as I, II or III.

Category II it shows tachycardia and minimum variability.

Classify the tracing as I, II or III and explain.

A baseline FHR of <110 BPM for at least 10 min. Contributing factor include stimulation the fetal vagus nerve possibly due to prolonged head compression or application of the forceps or vacuum, fetal cardiac conduction defect such as heart block, maternal hypotension and drugs that timulate the parasympathetic branch or block the sympathetic branch of the autonomic nervous system such as anesthesia and regional analgesia or hypoxemia. Hypoxic causes include maternal hypotension, placental abruption, cord prolapse or uterine rupture.

Define fetal bradycardia and factors that contribute to fetal bradycardia.

increase in FHR above baseline of at least 15 bpm above baseline, usually 15-20 sec duration and associated with intact fetus, unstressed by hypoxia and acidemia reassuring and usually indicates fetal well being. Before 32 wks an acceleration is at least 10 bpm above baseline with a duration of 10 seconds or greater. Prolonged accelerations last at least 2 min but less than 10 min. An acceleration over 10 min is a FHR baseline change.

Define fetal heart rate accelerations.

Chronic deficiency of placenta function, usually from an interruption of oxygenation pathway due to abruption, mat. hypo or hypertension or other issues. Infant is not tolerant of contractions. Can result in fetal grow restrictions (FGR)

Define Uteroplacental insufficiency (UPI)

Category I (normal) FHR tracings are normal & predictive of normal fetal acid-base status at that time. No action is required. Baseline FHR rate: 110-160BPM Baseline FHR variability: moderate Accelerations: present or absent Late or variable decelerations: absent Early decelerations: present or absent

Define a category I (normal) fetal heart rate tracing.

Category II (indeterminate) FHR tracings are indeterminate & not predictive of abnormal fetal acid-base status at that time. They do not reliably correlate with positive outcomes and require an evaluation and continued surveillance and reevaluation with review and consideration of all clinical factors. Interventions should be initiated appropriate to the situation, physician notified, and documentation. Baseline FHR rate: Bradycardia not accompanied by absent variability or tachycardia Baseline FHR variability: Minimal baseline variability, absent baseline variability not accompanied by recurrent decelerations, marked baseline variability Accelerations: the absence of induced accelerations after fetal stimulation Periodic or episodic decelerations: -recurrent variable decelerations accompanied by minimal or moderate baseline variability -Prolonged deceleration > 2 min but < 10 min -Recurrent late decelerations with moderate FHR baseline variability -Variable decelerations with other characteristics such as slow return to baseline, overshoots or shoulders

Define a category II (indeterminate) fetal heart rate tracing.

Category III (abnormal) FHR tracings are predictive of abnormal fetal-acid base status at that time & may be indicative of current or impending fetal asphyxia so sever that the fetus is at risk for injury & include: Absent FHR baseline variability with recurrent late decels, with recurrent variable decels, with bradycardia or sinusoidal patterns. They require prompt evaluation and resolution. Interventions include oxygen via non-rebreather mask, changing position, d/c of oxytocin and treatment of maternal hypotension.

Define a category III (abnormal) fetal heart rate tracings.

Shaped like an early decel-visually apparent, usually symmetrical, gradual decrease and return of the FHR associated with a contraction -the lowest point of the decel will occur after the peak of the contraction. They dip no more than 30-40 BPM below the baseline. This does not tell the degree of hypoxia.

Define a late deceleration

Visually apparent abrupt increases from the onset of the acceleration to peak in <30 seconds in the FHR above baseline. They may be periodic (assoc. w/contractions) or episodic (not assoc. w/contractions) The peak must be >15 BPM and must last >15 seconds from onset to return to baseline. Before 32 wks gest. an acceleration is defined as >10 BPM and a duration of >10 seconds.

Define accelerations in FHR

A decrease of blood flow and O2 delivery to fetus & increases CO2 level in fetus. Transient cord compression can be common in labor. Variable FHR decel's is frequently associated with cord compression.

Define cord compression.

Changes in the FHR from baseline. Can be periodic or episodic and are defined depending on their timing in relation to contractions. Classification of a tracing w/ decelerations depends on the the type and context of the tracing. They are quantified by depth and nadir in BPM(except transient spikes or electronic artifact). The duration is quantified in minutes and seconds from beginning to end of the deceleration.

Define decelerations of the FHR.

A baseline FHR of 160 BPM for at least 10 min. Contributing factors include hyperthermia, infections (maternal or fetal), maternal dehydration, hyperthyroidism, anxiety, drugs that stimulate the central nervous system, fetal immaturity, a cardiac conduction defect, or hypoxemia.

Define fetal tachycardia and factors that contribute to fetal tachycardia.

Fluctuations in the baseline FHR that are irregular in amplitude and frequency. Visually quantified as the amplitude of the peak to the trough in BPM within the baseline range. It is an indirect measure of fetal oxygenation.

Define fetal variability.

systolic BP >= 140mm hg, a diastolic BP>= 90 mm hg or MAP of >=105

Define maternal hypertension (gestational).

A decrease in FHR of > 15 BPM lasting > 2 min but < 10min from onset to return to baseline. Any decel longer than >10 min is a baseline change. Prolonged decels are due to a sudden significant change in the fetal environment rather than a repetitive stimulus. Immediate communication/ intervention is necessary.

Define prolonged deceleration of the FHR.

>5 contractions in 10 min (more frequently than Q 2 min) averaged over 30 min window. Caused by oxytocin, aminoinfusion or in rare cases spontaneously.

Define tachysystole contractions and the cause of.

higher conc. to lower concentration. 1.Oxygen from maternal (higher) to fetal compartment (lower) to fetal hgb then transported to fetal tissue. 2. CO2 returns to intervillous space by passive diffusion and is removed by the mat. venous system.

Describe passive diffusion as related to the maternal placental fetal system.

The electrode is sterilely inserted through the dilated 2-3 cm cervix to the presenting part. Gently turning the electrode clockwise 1.5 turns allows the spiral tip to penetrate the top layer of skin (scalp or buttock) avoiding fontanels, suture lines, face or genitals enabling production of the the ECG. Once secure remove the introducer & attach the wires to the leg plate & secure to mothers thigh or abd near symphysis. To remove turn counter clockwise, do not pull as it can cause injury. Wires are non sterile so remove prior to C/S.

Describe the procedures for application and removal of the FSE

1. Presentation (at the inlet of the pelvis)-palpate fundus if head is at fundus. 2. Position/lie (relationship of the presenting part to the pelvis anterior, posterior or transverse) and (long axis, fetal spine long smooth hard plane longitudinal, transverse or oblique.) 3. Descent (floating or engaged) grasp abd. above symphysis pubis note contour, size, consistency of presenting part. Head is firm, globular, mobile if unengaged and immoble if engaged. Breech is smaller, softer and irregular. 4. Prominence of the head over the pelvic brim. Press in direction of the pelvic inlet for cephalic prominence. If prominence is on opposite of fetal back is likely the forehead and is in vertex or well tucked position.

Describe the the 4 maneuvers of Leopold's maneuvers.

A. Absent notice the smoothness of the tracing indicating absent variability.

Describe the variability in this tracing: A. Absent B. Minimal C. Moderate D. Marked

D. Late decelerations notice the gradual decrease in baseline that follows the peak of each contraction.

Describe this tracing: A. Accelerations B. Early Decelerations C. Variable decelerations D. Late decelerations E. Episodic deceleration

Contraindications- Maternal infections like HIV, Hepatitis or GBS +, complete placenta previa, undiagnosed vaginal bleeding, do not place FSE on face, fontanels or genitalia.

Discuss contraindications for use of the FSE.

*IUPC is assoc w/ increased risk of uterine, placental and cord perforation. *is an invasive method *limits maternal ambulation *catheter tips may be wedged against wall or body part preventing accurate data *higher pressure readings may occur *maternal position may affect the pressure readings

Discuss the limitations of the IUPC

*check all attachment points *verify position (can be displaced or perforated uterus or uterine rupture) have pt cough/valsalva if place correctly tracing will spike with cough simultaneously palpate abd to verify presence/absence of contractions *a tracing with no visible resting tone may be improperly zeroed. *abnorm wave form can be due to IUPC lodging against uterine wall or body part *Notify MD if none of above helps and use another method to monitor such as toco or palpation

Discuss troubleshooting of the IUPC

Elevated tone 30 mmHg is above the normal resting tone of 20-25

Does this IUPC tracing show normal resting tone or elevated tone ?

Normal resting tone 15 mm Hg is with in the normal range of 5-20 mm Hg

Does this IUPC tracing show normal resting tone or elevated tone ?

Normal resting tone 15 mm Hg is with in normal range of 5-20 mm Hg

Does this IUPC tracing show normal resting tone or elevated tone?

No more than 20-30 BPM and rarely below 100-110 BPM

Early decelerations drop below baseline by how many BPM?

undetectable amplitude range can be indicative of impending fetal hypoxia

Explain absent FHR variability.

Its an isolated event sometimes in conjunction with a procedure. May occur in response to transient cord compression, uterine tachysystole or excessive uterine activity, administration of anesthetics, maternal position change, or vaginal exam. By definition, they do not occur uniformly or repetitively. Ask 3 questions: 1. is there an obvious event that caused the decel? 2. Does FHR return to baseline when the event is over? 3. Is there moderate variability assoc. with the decleration?

Explain an episodic deceleration and what causes episodic decelerations. What are the 3 questions to ask related to episodic decels?

Category II shows recurrent variable decelerations and a prolonged deceleration. Although recurrent variable decelerations appear, moderate baseline variability is still present. Note the presence of a prolonged deceleration may indicate a decline in fetal acid-base status so it may be trending towards a category III.

Explain and classify the tracing as I, II or III.

FSE is only direct method for monitoring the FHR & is less affected by outside interference. The tip if FSE is fine surgical grade wire in shape of corkscrew attached to the fetal presenting part. The electrode detects fetal heart electrical activity, sending and ECG signal to the monitor & produces PQRST waves. BPM are converted btwn R to R intervals.

Explain how the FSE monitors FHR.

Auscultate to confirm FHR. Turn off artifact elimination switch per manufacturers instructions. Check ECG cable and leg plate using self test per manufacturer. Check placement may be dislodged or attached to cervix instead of fetus. If none of the above works than apply new FSE or monitor by other means (US or auscultation)

Explain how to trouble shoot an FSE that shows intermittent makings on the tracing rather than a continuous line.

amplitude range >25 BPM

Explain marked variability.

amplitude >undetectable (visually detectable but less than or equal to 5 BPM) can be indicative of impending fetal hypoxia

Explain minimal variability.

amplitude range 6-25 BPM

Explain moderate variability.

May lead to hypoxemia and fetal acidemia. The depth of variable deceleration's is not enough to determine degree. Evaluate oxygenation through baseline heart rate characteristics through rate, variability and presence or absence of accelerations.

Explain persistent or recurrent cord compression concerns and what to look at.

Recurrent decelerations that occur with >50% of contractions in any 20 minute period. Intermittent decelerations occur with <50% of contractions in any 20 minute period.

Explain recurrent and intermittent decelerations.

Defined as having a smooth, sine wave-like undulating pattern in the FHR baseline with a cycle frequency of 3-5/min. that persists for at least 20 minutes. It DOES NOT represent variability. You usually see amplitudes of 5-15 BPM. You will not see any accelerations with the sinusoidal pattern. Decelerations with a sinusoidal pattern are an even more ominous sign.

Explain sinusoidal pattern FHR.

Generated in the fetal brainstem carried via the vagus nerve to the fetal heart. Stimulates vagus nerve which increases fetal blood pressure, decreases firing rate at SA node and decreases FHR. Also influences the presence of fetal heart variability. The parasympathetic nervous system matures later in pregnancy. This balances out the sympathetic branch, the baseline heart rate gradually decreases toward the middle of the normal range.

Explain the parasympathetic impulses of the fetal central nervous system.

You could stop oxytocin for recurrent late decels or diminishing FHR variability. You can add tocolytic's to reduce uterine activity. Terbutaline can be given to reduce excessive uterine activity (tachysystole). Anesthesia may = vasodilation/ mat hypotension to prevent normally prehydrate IV 500/1000ml crystalloid. Mat. hypotension can cause FHR tracing w late declel's, prolonged decels or bradycardia. Treat w epinephrine /norepinephrine = vasoconstrictions & improves utereoplacental blood flow. Amnioinfusion (NS or LR) can resolve cord compression in cases of oligohydramnios and variable decelerations.

Explain the pharmacologic interventions used for intrauterine resuscitation.

If the reflecting surface is moving the reflected signal has a frequency change known as a doppler shift. If the reflecting surface is moving toward the signal source the frequency of the signal increases; if the frequency decreases the surface is moving away. The back and forth movement of the fetal myocardium will produce an alternately higher and lower frequency. Stationary surfaces undergo no frequency change. The US ignores all reflected signals that have the same frequency as the transmitted signal. Those signals that have undergone a frequency change - a Doppler shift- are converted into electronic signals.

Explain the principles of the Doppler shift as related to FHR monitoring.

Generated in the fetal brainstem carried via sympathetic fibers to the heart. Increases FHR, strength of myocardial contraction of the heart and fetal cardiac output. Sympathetic stimulation influences FHR variability. The sympathetic branch of the autonomic nervous system is present very early in fetal development.

Explain the sympathetic impulses of the fetal central nervous system.

A normal part of labor. As contractions build increased uterine pressure prevents blood from entering/leaving the intervillous space. During the peak the fetus relies completely on its oxygen reserve (an aerobic challenge that is not an issue for a health fetus.

Explain transient interruptions in fetal oxygen supple during labor.

Monitors changes in the contour of the maternal abdomen caused by uterine contractions, is placed over the fundus. Can measure relative changes in pressure, duration and frequency of contractions. Can NOT measure intensity. Women with large amounts of abdominal adipose tissue can be difficult to monitor.

Explain what a Tocodynamometer is, what it measures and its limitations.

Most accurate method of assessing uterine contractions. Inserted through dilated cervix, its sensor tip monitors changes in pressure of the amniotic fluid. Measures resting tone, duration, frequency and intensity of contractions. Can NOT be used unless membranes are ruptured.

Explain what an intrauterine pressure catheter is, what it measures and its limitations.

too high or low FHR pattern- *maternal pulse interference, palpate mothers pulse compare to assure differentiation. *dysrhythmia can cause unusual pattern, auscultate FHR to confirm *May double FHR if below 30 BPM and 1/2 FHR if > 240BPM, establish rate by auscultation *test button to reset *check connections *reposition the US transducer *reposition the mother *monitor by other means (auscultation or fetal spiral electrode FSE)

Identify clinical measures for troubleshooting the ultrasound transducer.

External- Doppler ultrasound transducer (converts movement into sound to tracing on paper) Tocodynamometer (TOCO) monitors externally contractions. Internal- Fetal Spiral Electrode (FSE) monitors internally FHR. Intrauterine pressure catheter (IUPC) monitors internally contractions.

Identify the 4 types of electronic instrumentation used to assess FHR and uterine activity.

140 BPM Minimal variability Late decelerations Normal uterine activity Present accelerations

Identify the tracing characteristics: FHR Baseline FHR variability FHR Decelerations Uterine Activity FHR Accelerations

Tachycardia absent variability Variable decelerations Normal uterine activity Absent accelerations

Identify the tracing's characteristics: FHR Baseline FHR variability FHR Decelerations Uterine Activity FHR Accelerations

a. Uterine contraction wave form normal b. Maternal respiration c. Valsalva maneuver or pushing d. Maternal activity such as vomiting or seizure e. Fetal movement/activity f. Maternal position change or sudden baseline shift g. Obscured or low baseline setting h. Inverted waveform r/t placement of toco

Identify the uterine contraction variation:

a. Uterine contraction wave form normal b. Maternal respiration c. Valsalva maneuver or pushing d. Maternal activity such as vomiting or seizure e. Fetal movement/activity f. Maternal position change or sudden baseline shift g. Obscured or low baseline setting h. Inverted waveform related to placement of toco

Identify the uterine contraction variation:

140 BPM Moderate variability No decelerations Normal uterine activity Present accelerations

Identify this tracing's characteristics: FHR Baseline FHR variability FHR Decelerations Uterine Activity FHR Accelerations

Notify MD regarding the irregular rhythm, request physician assess for preterm labor and perform an ultrasound. If found + for preterm contractions she would be treated appropriately, then discharged to follow up with a level 2 ultrasound for confirmation of arrhythmia.

In this situation what could you do to be sure you are obtaining accurate information about FHR? 17y/o pt G2 T0 P1 A0 L1. She is 23 5/7wks gest, her mom is with her, states she has been contracting for several hours. Reports this is a normal pregnancy thus far. You assess using Leopold's to determine fetal position, palpating frequent movement but have difficulty detecting the FHR due to baby activity and size. A handheld Doppler helps to better locate FHR but an unusual rhythm. The electronic fetal monitor ultrasound signal shows an interrupted rate of 160BPM, irregular pattern with long interruptions in the rhythm.

Baseline FHR is 130 BPM which falls within the range of normal baselines 110-160 BPM

Is the baseline in this fetal tracing of a fetus at 40 weeks gestation normal or abnormal?

The baseline heart rate is 210 BPM which is outside the range of the normal baseline of 110-160 BPM.

Is this baseline in this fetal tracing of a fetus at 24 weeks gestation normal or abnormal?

Baseline FHR is 135 BPM which falls within the range of normal baselines 110-160 BPM

Is this baseline in this fetal tracing of a fetus at 26 weeks gestation normal or abnormal?

Palpation to determine presentation and position of the fetus and aid in location of fetal heart sounds. Head=hard, round, movable object Buttocks=soft and irregular shape Back=smooth, hard surface felt on one side of the abdomen Irregular knobs and lumps on opposite side of abdomen may be hands, feet, elbows, and knees

Leopold's Maneuvers

Advantage- FSE is only direct means of assessing the FHR. Limitations- *Most will not record R-R intervals (FHR) greater than 240 BPM *Maternal pacemaker may interfere. *Requires ROM and dilated cervix. *May measure maternal heart rate in case of fetal demise. *small possibility of electronic interference and artifact although less than with external ultrasound.

List advantages and limitations of the FSE.

Advantages-detects FHR baseline, variability, accels, decels, & rhythm. Provides permanent recording of tracing. Non-invasive, can be used prior to ROM and w/o cervical dilation. Limitations-Movement may result in weak or absent tracing. Elevated BMI, fetal position, presentation & anterior placental location my affect signal quality. May double FHR if below 30 BPM and 1/2 FHR if > 240BPM. US indirectly measures Fetal heart movement. External US monitoring may restrict ambulation.

List advantages and limitations of the ultrasound transducer.

failing to : monitor FHR or contractions evaluate the information obtained recognize deteriorating fetal condition taking appropriate actions in response to FHR patterns notify a provider and obtain a timely response monitor the FHR in the delivery room or OR prior to C/S

List documentation issues that may increase liability.

Maintaining mat. volume, mat. positioning, intravenous hydration. Decreasing mat. pain/anxiety. 1. Reposition pt to side. 2. Admin IV fluid bolus. 3. Admin 0.25mg terbutaline SQ. 4. Admin O2 10L via non rebreather face mask.

List interventions for tachysystole contractions.

1. Performing Leopold's maneuvers. 2. Applying the conduction gel. 3. Securing the ultrasound. 4. Reading the FHR tracing.

List the 4 steps in using the external ultrasound device.

latent phase <4cm latent phase 4-5cm active phase >6cm second stage passive fetal descent second stage active pushing

List the phases of (latent/active/2nd) labor and their associated descriptions.

Place her in lateral position, & increase IV fluids. If no improvement may need to give epi to increase vascular tone.

Maternal hypotension is a potential side effect of regional anesthesia and analgesia. What nursing interventions could you use to raise the client's blood pressure? Choose all that apply. A) Place the woman in a supine position. B) Place the woman in a lateral position. C) Increase intravenous (IV) fluids. D) Continuous Fetal Monitor E) Administer ephedrine per MD order

(Per AWHONN) If no risk factors are present at admission, evaluate the standard Q 30 min in the latent (4-5 cm) and active phases of the 1st & 2nd stage passive fetal descent phase and Q15min in the 2nd stage active pushing stage of labor. If risk factors present on admission or appear during labor evaluate Q 15 min during active phase, the 2nd stage passive fetal descent, and at least Q 5 mind during 2nd stage active pushing. If the FHR baseline changes in my 10 min window document what the tracing shows you. Write a note describing it. If baseline started out at 120 BPM and increases to 130 BPM...write it.

Monitoring and intervention questions: What should I do if the fetal heart rate (FHR) baseline changes? What if the FHR baseline changes in my 10 min window?

failing to : perform initial assessment ongoing mat/fetal assessments recognize changes in mat/fetal status take appropriate precautions /actions neglecting to document or communicate information notify and obtain timely response involvement in a surgical team's error stabilize and transport appropriately

Name areas of potential liability.

Ultrasound monitors externally FHR. Fetal Spiral Electrode (FSE) monitors internally FHR. Tocodynamometer (TOCO) monitors externally contractions. Intrauterine pressure catheter (IUPC) monitors internally contractions.

Name several techniques/devices of fetal monitoring.

Early Late Variable Prolonged

Name the 4 types of decelerations of FHR

decrease or slow down

Parasympathetic impulses decrease or increase a fetal heart rate?

increase or speed up

Sympathetic impulses decrease or increase a fetal heart rate?

a) Throughout labor and delivery unless the use of a more accurate method is clearly indicated

The FHR can be monitored using doppler ultrasound? a) Throughout labor and delivery unless the use of a more accurate method is clearly indicated b) Internally c) Only early in labor d) The FHR cannot be monitored by doppler ultrasound

Category I as it has accelerations, moderate FHR variability, normal FHR baseline and no interventions are needed at this time.

The tracing is classified as: Category I Category II Category III

A baseline with in normal range. The range is 110-160 BPM

The tracing shows: Tachycardia A baseline within normal range Bradycardia

Moderate the jaggedness of this tracing indicates variability is present, and the amplitude of variability is between 6 and 25 BPM.

The variability in this tracing is: Absent Minimal Moderate Marked

C. Tocodynamometer

This instrument: -Is used to eternally monitor uterine contractions. - Is noninvasive and can be placed without rupture of membranes. -Cannot detect uterine resting tone or exact intensity of contractions. A. Doppler Ultrasound B. Fetal Spiral electrode C. Tocodynamometer D. Intrauterine pressure catheter

A. Doppler Ultrasound

This instrument: -Is used to externally monitor the fetal heart rate. -Is noninvasive and can be placed without rupture of membranes. -May be affected by maternal or fetal motion. A. Doppler Ultrasound B. Fetal Spiral electrode C. Tocodynamometer D. Intrauterine pressure catheter

D. Intrauterine pressure catheter

This instrument: -Is used to internally monitor contractions. -Provides absolute, rather than relative, measurements. -Carries with it a slightly increased chance of uterine infection. A. Doppler Ultrasound B. Fetal Spiral electrode C. Tocodynamometer D. Intrauterine pressure catheter

B. Fetal Spiral electrode

This instrument: -is used internally to monitor fetal heart rate. -detects fetal heart rates up to 240 bpm -requires rupture of membranes and cervical dilation for placement. A. Doppler Ultrasound B. Fetal Spiral electrode C. Tocodynamometer D. Intrauterine pressure catheter

B. A baseline within normal range The baseline is 150 BPM which is within the range for normal fetal baseline heart rate.

This tracing shows: A. Tachycardia B. A baseline within normal range C. Bradycardia

Mother's inhalation to lungs to mat. circulatory system to hemoglobin in RBC's to bloodstream in uterus. Uterus to spiral arteries to placenta to intervillous space to travel via simple diffusion into the villi. The capillaries to the umb. vein to the fetus. The umb. artery sends waste (CO2) to the intervillous space to the mothers venous system.

Trace the flow of oxygen from mother to fetus and back.

Assess fetal lie, presentation, position and descent by abdominal palpation. This includes 4 maneuvers to assess the fetal part in the upper uterus, location of fetal back, presenting part and descent of the presenting part.

What are Leopold maneuvers are used to determine?

Must be 2 min of segments. Range 110-160 BPM (represented in a multiple of 5) <32 weeks is usually high normal >32 weeks gradual decrease due to increased vagal tone. Change in baseline is >10min.

What are fetal baseline guidelines? Range? <32 weeks gest >32 weeks gest change in baseline

1. When labor and not progressing & assessment of the adequacy of the contraction is needed. 2. When the nature or event of previous uterine scarring necessitates internal monitoring 3. Amnioinfusion is required 4. Differentiation of FHR patterns relative to contractions is needed

What are indications for IUPC monitoring?

Abnormal fetal acid-base status and require an evaluation and prompt intervention.

What are late decels with absent variability predictive of?

Early Late Variable

What are the 3 classifications of periodic decelerations?

Advantages- it is external so it is non invasive and ROM is not necessary Limitations- it is location sensitive so improper placement or movement can cause uninterpretable tracing. It is not a means of assessing true resting tone or intensity so must use in conjunction with direct palpation. Toco only gives an approximate measure of duration and frequency. Reading can vary greatly based on mat. weight, mat. position, and position of belt.

What are the advantages and limitation of Toco?

1. Higher baseline FHR i.e. a 23 wk gest may have a baseline of 155 BPM but at term, the same baby may have a baseline of 130 BPM. Any baseline above 160 BPM is still considered tachycardia. 2. Decreased variability bc the central nervous system is not fully developed, variability may be decreased. 3. lower amplitude accels in preterm (before 32 wks) accels of at least 10 BPM above baseline for at least 10 sec is acceptable. 4. more frequent occurrences of variable decels

What are the different characteristics of a fetus prior to 32 wks gest. than a term fetus?

Generally, the goal of all 3 categories is fetal oxygenation. You are determining the impact of contractions on fetal oxygenation. Category I- (normal) no intervention fetus is sufficiently oxygenated. Category II-(Indeterminate) FHR patterns may indicate problems in the oxygenation pathway but no clue as to severity/effect on the fetus. Category III- (abnormal) fetal oxygenation is severely compromised resulting in hypoxemia and possible acidemia.

What are the interventions for category I, II and III?

Recurrent if they occur in > 50% of contractions in any 20 min segment. Intermittent if they occur in < 50% of contractions in any 20 min segment.

What are the parameters for decelerations to be recurrent versus intermittent?

May be periodic or episodic, the most common pattern seen during labor. Their shape and depth are variable, not like early or late's, rarely smooth and regular. A visually apparent abrupt decrease in FHR from onset of decel to nadir of <30 seconds. The decrease is >15 BPM lasting >15 seconds and < 2 minutes in duration. Usually assoc. with cord compression, fetal baroreceptors increase the FHR to maintain cardiac output.

What are variable decelerations?

Prior to a contraction the umbilical arteries and vein are wide open; fetal BP is stable. With the beginning of the contraction of the vein, then the arteries are compressed & the fetal body detects decreased blood flow from the fetal heart. In response, the fetal baroreceptor increases the FHR to maintain cardiac output. As it continues to strengthen arteries are compressed increasing fetal BP. The vagus nerve slows down FHR. As the contraction eases the umbilical arteries are released and FHR returns to baseline, fetal HTN is resolved and carbon dioxide can be cleared from the fetal body. Lastly the umb. the vein is released, blood press stabilizes and oxygenation normalizes.

What causes a variable deceleration?

Umb. cord -Proplapse Mat. inhalation -Asthma Placenta -Calcification Uterus -Tachysystole Fetus -Rh isoimmunization (fetal anemia) Mat. circulation -Hypertension

What conditions impact the following pathways: Umbilical cord Maternal inhalation Placenta Uterus Fetus Maternal circulation

relieve cord compression, maximize umb. circulation and rule out cord prolapse and amnioinfusion. Admin oxygen by non-rebreather facemask, reduce or stop oxytocin to decrease uterine activity if needed. Inform the physician if recurrent variable decels with absent FHR baseline variability as a quick delivery may be necessary.

What do you do if variable decelerations are associated with absent FHR variability or abnormal baseline rate and the absence of accelerations?

A compromised fetus. possible causes are severe fetal anemia from RH isoimmunization, massive feto-maternal hemorrhage, ruptured vasa previa, twin to twin transfusion, fetal intracranial hemorrhage.

What does it mean to have an undulating FHR pattern? What are the causes of undulating patterns in FHR?

An increase in variability from moderate to marked may indicate early stages of fetal hypoxemia or can be normal. Therefore baseline is a key assessment.

What does marked variability suggest?

Moderate variability shows intact neurological modulation of the FHR, normal cardiac responsiveness, and fetal reserve. This predicts the absence of fetal metabolic acidemia at the time it is seen and indicates the fetus is well oxygenated.

What does moderate variability suggest?

Abnormal fetal acid-base status and possible hypoxemia or impending acidemia. This pattern requires prompt evaluation and intervention.

What does persistent absent variability of the FHR in combination with recurrent late or variable decelerations or bradycardia suggest?

Contractions by detecting abdominal wall contour changes. The device converts this to electronic impulses that register and print out on paper. Toco does NOT quantify resting tone or intensity of contractions. Changes of the abd wall can be caused by a number of events besides contractions (mat. respirations, pushing, vomiting, seizures, fetal activity and movement). A normal contraction creates a smooth and even fall on the tracing

What does the Tocodynamometer measure?

Marked- note the wide span of the fluctuations in the baseline FHR. In this case the fluctuations are >25BPM.

What is the variability?

Can be a sign of inadequate oxygenation, may indicate a fetal central nervous system or cardiovascular anomaly, or may indicate a pre-existing fetal brain injury. May also result from maternal medications such as mag sulfate or narcotics.

What does the absence of variability suggest?

Late decels with normal FHR baseline, moderate variability and/or accelerations can be managed conservatively versus late decels with minimal or absent variability. Interventions are toward maximizing uteroplacental blood flow thereby improving oxygen delivery to the fetus. Turn mom on her side, increase IV fluids, decrease or d/c oxytocin, notify MD. Document assessment, interpretation, interventions and evaluate effects of actions.

What does the presence of late decelerations tell us about the oxygen status of the fetus?

1. Mother (blood plasma, cardiac output, hemoglobin concentration & O2 saturation) 2. Placenta/intervillous space (uterine contractions & calcification's) 3. Fetus (vagal response aka decel or cord compression)

What factors impact maternal oxygen delivery?

A method of assessing fetal acid-base status through vigorously rubbing the fetal head with a gloved hand to elicit an acceleration. This is dune when FHR is at baseline. Do not do during a deceleration to attempt to increase the FHR. A well-oxygenated fetus will respond with an acceleration of 15 BPM or more for > 15 seconds. This is a reliable prediction of the absence of fetal metabolic acidemia at that time. This does not predict fetal acidemia or fetal compromise. Stimulation is not needed if the tracing has category I characteristics.

What is Scalp Stimulation?

MVU's quantify uterine activity over 10 min period, requires the use of an IUPC. Minus the resting tone from the peak intensity of each contraction in a 10 min period and add the values together. At least 200 MVU's results in progressive cervical change.

What is a Montevideo unit (MVU)? How do you calculate MVU's?

a visually apparent decrease in FHR below the baseline rate of 15 bpm or more and lasting > 2 minutes but < 10 minutes, prolonged decels are usually isolated events that end spontaneously. Prolonged decel's typically have an abrupt onset, reach the nadir in <30 sec, and are in response to a sudden significant change in the fetal environment. IF > 10 min it is a baseline change. With prolonged decelerations, further maternal and fetal assessment is needed to determine if immediate intervention is needed.

What is a prolonged deceleration?

It is the only method that directly measures the uterine resting tone, contraction intensity, frequency and duration. It is an invasive procedure that requires ROM and cervical dilation. IUPC is used when there is a need for more detailed information than palpation or toco can provide. The IUPC measures hydrostatic pressure in the uterus, measuring intrauterine pressure during and between contractions.

What is an Intrauterine pressure catheter (IUPC) and what does it measure?

Overshoots are exaggerated compensatory increases in FHR after a variable deceleration. Overshoots are usually at least 10-20 BPM above baseline range and at least 20 seconds in duration. Overshoots are usually accompanied by minimal or absent variability and a gradual return to baseline FHR. They resemble accelerations however unlike accels their significance to fetal acid-base status is unclear.

What is an overshoot?

Duration of contractions lasting more than 120 second may have a negative impact on fetal oxygenation.

What is an unfavorable duration for contractions?

A frequency of (tachysystole) more than 5 contractions in 10 min. over a 30 min. window.

What is an unfavorable frequency of contractions?

Intensity via palpation is termed mild, moderate or strong. Intensity via IUPC averages 30mm hg in early 1st stage, 50-60 in the later 1st stage and 70-80 in the second stage of labor.

What is contraction intensity and what are the averages via IUPC during early 1st stage, late 1st stage, and the 2nd stage of labor?

Intrauterine resuscitation's refer to interventions done to correct Category II (indeterminate) and category III (abnormal) FHR characteristics : shifting maternal position, maternal IV hydration, administering oxygen and reducing pain and anxiety and modification of maternal pushing efforts during the 2nd stage of labor. Also you could stop oxytocin for recurrent late decels or diminishing FHR variability. You can add tocolytic's to reduce uterine activity. Terbutaline can be given to reduce excessive uterine activity (tachysystole)

What is intrauterine resuscitation?

Resting tone when assessed externally is termed soft or firm. When assessed via IUPC 5-20 is normal, >20 may be elevated tonus and can hinder O2/CO2 exchange.

What is resting tone and how is it described?

It is the heart's internal pacemaker. It is specialized clump of cells at the top of the right atrium that gives electrical impulses to cause the heart to beat. The intrinsic rate is 110-160 in term fetus. Early in gestation (15-20 wks) can be much higher. In 26-28 weeks may be in the upper range of normal.

What is the SA Node?

Periodic are associated with uterine contractions. Episodic are NOT associated with contractions.

What is the difference between decelerations that are periodic and episodic?

-Duration (the time elapsed from beginning to end) 60-80 seconds = 6-8 small boxes -Frequency (time elapsed from beginning of one contraction to the beginning of the next) 2 minutes = 2 darker vertical lines

What is the duration? What is the frequency?

Variable Decelerations, which are a visually abrupt decrease in the fetal heart rate (<30 seconds from onset to beginning of the nadir). The decrease is >15 BPM lasting >15 seconds and < 2 min in duration

What is the most common decel pattern seen in labor?

17g/dl, fetal hgb has a higher oxygen affinity than an adult to develop in an oxygen poor environment. The fetal circulatory pattern ensures blood with higher O2 and nutrition content is delivered to the vital organs (brain and heart) to tolerate the stress of labor.

What is the normal expected value for a term fetal HGB?

b) 110-160 bpm

What is the normal range for FHR base line in a term infant? a) 80-120 bpm b) 110-160 bpm c) 140-180bpm d) it depends on the sex of the fetus

Absent-fluctuations in the FHR are not detectable.

What is the variability?

Document what you see on the tracing. If baseline starts at 120 BPM and increases to 130BPM for 10 min or more this is a baseline change. If the FHR continues to show characteristics of a Category I tracing cont. routine assessment and doc. of variability, accels, uterine activity and other changes you observe.

What should I do if the fetal heart rate baseline changes?

It is likely the tracing is showing the maternal heart rate not the FHR. Readjust the monitor, searching for fetal heart tones, using leopold's maneuvers also assess for for signs of fetal oxygenation with fetal movements. Oxygenation can not be assumed or confirmed without assessing the FHR.

What should I do if the mothers palpated pulse matches what I hear coming from the monitor?

Maternal pulse detected Intermittent markings There is no problem

What the possible cause for the problem with this tracing ?

Maternal pulse detected There is no problem The FHR is abnormally low. Confirm maternal pulse by palpation and replace FSE. OR It is possible the fetus is bradycardic.

What the possible cause for the problem with this tracing ?

Maternal pulse detected Intermittent markings There is no problem Turn off logic switch, check circuitry by a self test, check electrode placement, confirm FHR by auscultation

What the possible cause for the problem with this tracing?

When information can not be obtained by palpation or use of toco and if there are no contraindications to its use. i.e. increasing oxytocin w/ elevated BMI if contractions are not being detected using toco.

When should an IUPC (intrauterine pressure catheter) be placed?

When the US is not recording a consistent tracing. Cervix should be 1-2 cm dilated and there should be no contraindications to the procedure per the maternal history and labor status.

When should the fetal spiral electrode (FSE) be applied?

Between 5-20 mm Hg IUPC gives a quantified measure of intrauterine pressure.

When using IUPC what is the resting tone or baseline? What is the IUPC measuring?

10-20 mm Hg (this is an arbitrary #) Toco detects increases and decreases but can not quantify pressure.

When using toco what do you set the uterine resting tone or baseline to? What is toco measuring?

a) Frequency b) Duration

Which contraction characteristics can be assessed with a tocodynamometer? a) Frequency b) Duration c) Intensity

Accelerations

Which of the following fetal heart rate characteristics does the tracing show: Acceleration Early decelerations Variable decelerations Late decelerations Episodic decelerations

The primary obstetric provider.

Who may insert an IUPC?

1 vein, 2 arteries encased in wharton's jelly. O2 (high content) travels via the vein CO2 travels via 2 arteries back to placenta

detail the umbilical cord


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