Intrapartum fetal monitoring

h Historical background
h Electronic Fetal Monitoring
h Other intrapartum fetal assessment techniques
h Nonreassuring fetal status
hMeconium in the Amniotic fluid
hManagement of NR-FHR patterns
h FHR patterns and Brain Injury
h Current Recommendation of EFM
h Intrapartum surveillance and Uterine activity
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vHippocates is said to have described the technique of listening to
the activities of internal body parts
vPerception of fetal heart sound in 1600
vYoung woman heart beat detected by rolling sheets of paper over
her chest in 1816 which later is replaced by wood
vIn the late 1960’s and early 1970’s: the dev’t of EFM
vEFM was used primarily in complicated pregnancies but gradually
became used in most pregnancies
vNow adays more than 85 percent of all live births in the United
States undergo EFM
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vTo study the forces exerted by labour, a rubber bag was inserted into
the Ux which was connected with a manometer
vIn this way it was found that the IUP in the intervals between the
contractions was represented by a column of 20mmHg high
vTonicity of the walls 5mmHg and its contents 15mmHg
vDuring labor pain the mercury rose considerably reaching a height of
from 80 to 250 mm
vCaldeyro-Barcia and Poseiro (1960) from Montevideo, Uruguay were
pioneers in elucidating the patterns of spontaneous uterine activity
throughout pregnancy
vRemot (wireless)monitoring of FHR (Ex...Novii patch) in 2015
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vIntrapartum fetal monitoring (IFM) means simply to watch the fetal
behavior during labor
vThe goal of IFM is to detect hypoxia in labor and to initiate
management depending upon the severity of hypoxia
vEven in a normal labor the baby is subjected to stress due to:
(1) Uterine contractions temporarily curtailing the uteroplacental
circulation
(2) Head compression affecting the function of the vital centers of
the brain
vMore appropriate term to use is “Nonreassuring fetal status”
than “fetal distress” now adays
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❶
❷
❸
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vIntermittent auscultation of FHR using an ordinary stethoscope or a
fetoscope or a handheld Doppler can be done to note its rate, rhythm
and intensity
vThe auscultation should be made for 60 seconds particularly before
and immediately following a uterine contraction
Limitations
(1) As it is a periodic observation, any transient significant abnormality in
between observations is likely to be overlooked
(2) Inherent human error
(3) Difficult to count the FHR during uterine contractions or in case of
obesity or hydramnios
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v Using Electronic Fetal Monitoring (EFM) and IUP catheter
v Ultrasound doppler effect is used to detect fetal pulse rate
from major fetal vessels
Ø This observation has to be rechecked when an
abnormality is detected
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v
1) Internal (Direct) Electronic Monitoring: using
fetal scalp electrode and IUP catheter
2) External (indirect) Electronic Monitoring: Using
the Ultrasound doppler principle and using external
tocodynamometer
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vAccomplished by attaching a bipolar spiral electrode directly
to the fetus
vThe wire electrode penetrates the fetal scalp, and the second
pole is a metal wing on the electrode
vThe electrical fetal cardiac signal: P wave, QRS complex, and
T wave is amplified and fed into a cardiotachometer for FHR
calculation
vThe peak R-wave voltage is the portion of the fetal
electrocardiogram (ECG) most reliably detected
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vWhen the fetus is dead, the maternal R waves are still
detected by the scalp electrode as the next best signal
and are counted by the cardiotachometer
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v
üPrecise FHR monitoring
üIdeal to use in obese women and hydramnios in which
external monitoring will be technically difficult
vDisadvantages of internal EFM
üThe need for rupture of membrane
üRisk of infection
üRisk of Injury to the fetus, Placenta and uterine perforation
üDifficulty in monitoring twin fetuses
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vThe FHR is detected through the maternal abdominal wall
using the ultrasound doppler principle
vUltrasound waves undergo a shift in frequency
vConsists of a transducer that emits ultrasound and a
sensor to detect a shift in frequency of the reflected sound
vTransducer is placed on the maternal abdomen at a site
where FHR is best detected
vA coupling gel must be applied
vThe device is held in position by an elastic belt
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vUltrasound Doppler signals are edited electronically
before FHR data desplayed on the monitor
vReflected ultrasound signals from moving fetal heart
valves are analyzed through a microprocessor
vThe
vBased on the principle that the FHR has regularity where
as noise is random and without regularity
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vElectronic editing greatly improved the tracing quality of
externally recorded FHR
vMonitor twin fetuses and concurrent maternal heart
rate
vDisplay the fetal ECG and record maternal pulse oximetry
values
vTechnological advances allow FHR monitoring from a
remote centralized location
vThe detection accuracy declined as the number of displays
increased
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vNICHD-RPW 2008 propose standardized and unambiguous
definitions for interpretation of FHR patterns during labor
vAdopted by the ACOG
vChoice of vertical and horizontal scaling greatly affects the
appearance of the FHR pattern
vScaling factors recommended by the NICHD Workshop:
ü 30 beats per minute (bpm) per vertical cm and
ü 3 cm/min (1cm/min) chart recorder paper speed
vPattern recognition can be considerably distorted depending
on the scaling factors used
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vThe modal characteristics that prevail apart from periodic
accelerations or decelerations associated with Uterine (Ux)
contractions
vDescriptive characteristics of baseline fetal heart activity:
ü
ü
ü
ü
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vDecreases with increasing fetal maturation
vNormal gradual slowing of FHR corresponds to maturation of
parasympathetic (vagal) heart control
vBaseline FHR is the approximate mean rate rounded to
increments of 5 bpm during a 10min tracing segment.
vMinimum interpretable baseline duration must be at least 2
minutes
vNormal FHR is [110 to 160]
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vThe average FHR is considered the result of tonic balance
between accelerator and decelerator influences on
pacemaker cells
ü Baseline FHR < 110 BPM
ü A rate between 100 and 119 BPM in the absence of other changes is
usually not considered to represent fetal compromise
vCaused by:
Ø Congenital heart block
Ø Serious fetal compromise
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Bradycardia comoliated by Abruption

v Baseline FHR >160 BPM
v Urgent intervention needed if concomitant deceleratiosns
v Can be caused by:
ü Maternal fever
ü Maternal hypotension from Epidural analgesia
ü Fetal compromise
ü Cardiac arrhythmias
ü Maternal use of PNS inhibiting drugs ( like atropine)
ü Sympathomimetics (terbutaline) drugs
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vUnsteady and wanders between 120 and 160 BPM
vSuggestive of a neurologically abnormal fetus
vMay occur as a preterminal event
v
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vNormal beat to beat variability is 6 to 25 BPM
vAn important index of cardiovascular function
vRegulated largely by the ANS push and pull effect mediated
via the SA node
vProduces moment to moment or beat to beat oscillation of
the baseline heart rate
vVariability can be analyzed over the short term and long
term
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hReflects the instantaneous change in FHR from one beat or R wave
to the next
hA measure of the time interval between cardiac systoles
hReliably determined to be normally present only when
electrocardiac cycles are measured directly with a scalp electrode
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hIs used to describe the oscillatory changes during
1 minute
hResult in the waviness of the baseline
hThe normal frequency of such waves is
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vPrecise quantitative analysis of both short and long term
variability is needed to avoid problems related to technical
and scaling factors
vNow adays no evidence suggests that the distinction
between short and long term variability has clinical
relevance
vIn actual practice they are visually determined as a unit
vGrades of baseline fetal heart rate variability: 4/5
grades
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vDefined as an excursion of the baseline of >5 BPM
hCan be affected by several and
processes
hGreater variability with fetal breathing and body
movements
hIncreased baseline variability with advancing
gestation
hAfter 30 weeks, fetal inactivity is associated with
diminished baseline variability
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hFetal activity enhanced beat to beat variability
hLess cardiovascular physiological wandering as beat to
beat intervals shorten with a higher FHR
hThe baseline FHR becomes more physiologically fixed
as the rate rises
vDefined as an excursion of the baseline of ≤5 BPM
vRelated to fetal inactivity in the absence of fetal insult
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v Caused by:
hAdministration of analgesic drugs during labor
üVarious CNS depressant drugs (narcotics,
barbiturates, phenothiazines, tranquilizers) and
üGeneral anesthetics
hUse of Corticosteroids for preterm Px
hUse of Magnesium sulfate (tocolysis/ HDP)
hSevere maternal acidemia like DKA can also lower fetal
beat to beat variability
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vMild degrees of fetal hypoxemia initially have been reported
to enhance variability
vReduced baseline FHR variability is the single most
reliable sign of fetal compromise
vAn ominous sign indicating a seriously compromised fetus
when loss of variability in combination with decelerations
vA persistently flat FHR baseline within the normal baseline
rate range and without decelerations may reflect a previous
fetal insult that has resulted in neurological damage
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vEpisodes of bradycardia <100 bpm, tachycardia >180 BPM
and abrupt baseline spiking
vArrhythmia can only be documented when scalp
electrodes are used
vAnalysis and interpretation of rhythm and rate disturbances
are severely limited from scalp electrode signals as only one
lead is used
v Arrhythmias were encountered in 3 percent of gestations
between 30 to 40 Wks
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vIntermittent baseline bradycardia is frequently due to
congenital heart block
vComplete AV block usually are found in association with
maternal connective tissue diseases
vMost fetal arrhythmias without comorbid fetal hydrops are
inconsequential during labor and antepartum but may
hinder interpretation of FHR tracings
vSonographic evaluation of detailed fetal anatomy and ECHO
can be useful
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v True sinusoidal pattern Can be caused by:
ü Fetal ICH
ü Severe fetal asphyxia
ü Severe fetal anemia
ü Anti-D alloimmunization
ü Fetomaternal hemorrhage
ü Twin-twin transfusion syndrome
ü Fetal parvoviral infection
ü Vasa previa with torential bleeding
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v Modanlou and Freeman (1982) proposed adoption
of a strict definition for True sinusoidal FHR
patterns:
1) Stable baseline FHR of 120 to 160 bpm with regular oscillations
2) Amplitude of 5 to 15 bpm (rarely greater)
3) Long-term variability frequency of 2 to 5 cycles per minute
4) Fixed or flat short-term variability
5) Oscillation of the sinusoidal waveform above or below a
baseline
6) Absent accelerations
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vThe pattern associated with alphaprodine is
indistinguishable from true sinusoidal pattern
vIn order to quantify fetal risk is clssified as:
Ø Mild: Amplitude 5 to 15 BPM
Ø Intermediate: Amplitude 16 to 24 BPM
Ø Major: Amplitude ≥25 BPM
vIntrapartum sine wave like baseline variation with periods
of acceleration defined as pseudosinusoidal which is
seen in 15 percent of monitored labors normally
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q
v Maternal administration of:
ØMeperidine, Morphine
ØAlphaprodine and Butorphanol
v Chorioamnionitis
v Fetal distress and
v Umbilical cord occlusion
v Sine waves are occurring at a rate of 6 cycles per minute
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Intrapartum
sinusoidal
FHR patterns
are not
generally
associated
with fetal
compromise

vAbout 4 percent of fetuses demonstrated sinusoidal
patterns transiently during normal labor
vThe pathophysiology of sinusoidal patterns is unclear
vSeems to have general agreement that antepartum sine
wave baseline undulations portend severe fetal anemia
vIt’s related to waves of arterial blood pressure
vReflecting oscillations in the baroreceptor-chemoreceptor
feedback mechanism
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vRefers to deviations from baseline that are temporally
related to uterine contractions
v refers to a rise in FHR above baseline
v is a drop in FHR below the baseline
h The nomenclature most commonly used is based on the
timing of the deceleration in relation to contractions:
ü Early deceleration
ü Late deceleration
ü Variable deceleration
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vAn abrupt increase above the baseline FHR
vDefined by an onset to peak rise within 30 seconds
Ø Has a peak ≥15 BPM above baseline
Ø Its duration is ≥15 sec but <2 minutes from onset to
baseline return
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Ø A peak ≥10 bpm for 10 seconds to 2 minutes is
considered normal
vProlonged acceleration is defined as ≥2 minutes but
<10 minutes
hMost often occur antepartum, in early labor and in
association with variable decelerations
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vMechanisms for intrapartum accelerations
include:
ü Fetal movement
ü Stimulation by uterine contractions
ü Umbilical cord occlusion
ü Fetal stimulation during pelvic examination
ü Scalp blood sampling and
ü Acoustic stimulation
vThese are virtually always reassuring and
at that time
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vAccelerations represent intact neurohormonal and
cardiovascular control mechanisms linked to fetal
behavioral states
vFHR accelerations during the first or last 30 minutes during
labor or both were a favorable sign for fetal well-being
vThe absence of such accelerations during labor is not necessarily
an unfavorable sign
vThe chance of acidemia in the fetus that fails to respond to
stimulation in the presence of an otherwise nonreassuring
pattern approximates 50 percent
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vA physiological response classically attributed to fetal
head compression
vA gradual FHR decline and return to baseline associated with a
contraction
vThe degree of deceleration is generally proportional to the
contraction strength
vRarely falls below 100 to 110 BPM or 20 to 30 BPM below baseline
vSuch decelerations are common during active Phase
vNot associated with tachycardia, loss of variability or other FHR
changes
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 Early Deceleration

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.Early Dec.n
.Variable Dec..n

vThe FHR response to Ux contractions reflects uterine perfusion or
placental function
vA smooth, gradual and symmetrical decline in FHR beginning at or after
the contraction peak
vThe onset, nadir and recovery of the deceleration occur after the beginning,
peak and ending of the contraction
vMagnitude of late decelerations is seldom more than 30 to 40 bpm below
baseline rate
vThe lower the fetal SPo2 before contractions, the shorter the
lag to the onset of late decelerations
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 Late Deceleration

vThis lag reflected the time necessary for the fetal Po2 to fall
below a critical level necessary to stimulate arterial
chemoreceptors
v
vVariability of the baseline heart rate disappeared as acidemia
developed
v Can be caused by any process that producess:
Ø Maternal hypotension (from epidural analgesia)
Ø Excessive uterine activity (oxytocin stimulation)
Ø Placental dysfunction from maternal disease
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v
vThe onset of deceleration typically varies with successive
contractions
vThe most frequent deceleration patterns encountered during
labor
vClassically attributed to umbilical cord occlusion
vOccurrs only after umbilical blood flow was reduced by at least
50 percent
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vThe extent of cord occlussion determines the form of deceleration
A.
Ø Absent of shoulders of acceleration before and after the deceleration
B.
ØShoulders of acceleration before and after the deceleration
component
ØOcclusion of only the vein reduces fetal blood return triggering a
ØIncreasing IUP and subsequent complete cord occlusion causes fetal
systemic HTN due to obstruction of umbilical arterial flow
ØThis stimulates a
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vThe pattern consists of rapidly recurring couplets of
acceleration and deceleration
vCauses relatively large oscillations of the baseline FHR
vFirst linked to during labor
vSeen in in association with cord
occlusion
v Not associated with fetal compromise
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Saltatory Pattern

vIs a pattern involving an acceleration followed by a variable
deceleration with no acceleration at the end of the deceleration
vThis pattern typically is seen in
vMay result from mild cord compression or stretch
vIs a variable deceleration followed by acceleration
vThe clinical significance of this pattern is controversial
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vDefined as an isolated deceleration ≥15 bpm that lasts ≥2
minutes but <10 minutes from onset to return to baseline
vCan be Caused by:
h Cervical examination and impending delivery
h Uterine hyperactivity
h Cord entanglement and prolapse
h Maternal supine hypotension
h Epidural, spinal or paracervical analgesia
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vDecelerations are virtually ubiquitous
vBaseline tachycardia or Bradycardia and loss of variability
vProlonged second-stage decelerations were associated with
a stillbirth and neonatal death
vAs the total number of decelerations <70 BPM increased,
the 5-minute Apgar score decreased
vLoss of beat-to-beat variability and baseline FHR <90 BPM
predicted fetal acidemia
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vPersistent or progressive baseline bradycardia or baseline
tachycardia was associated with lower Apgar scores
vAbrupt FHR deceleration to <100 BPM associated with
loss of beat-to-beat variability for 4 min or longer is
predictive of fetal acidemia
vAbnormal baseline FHR and absent beat to beat
variability or both in the presence of deep second stage
decelerations is associated with a greater risk for fetal
compromise
v
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vUse of admission EFM did not improve neonatal
outcome
vIncrease number of interventions including operative
delivery
vNo need to do for elective Cesarean deliveries
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vFetal heart rate pattern interpretations are subjective
vPerinatal outcomes such as intrapartum stillbirth,
early neonatal death and neonatal encephalopathy
were not improved by computer assisted
interpretation
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v To measure the pH and Lactate level in capillary scalp
blood
v Either way is equivalent in predicting fetal acidemia
v Low amount of sample needed for lactate (5μl-Vs-50μl)
v Identify the fetus in serious distress
v The pH of fetal capillary scalp blood is usually lower than
that of umbilical venous blood and higher than that of
umbilical arterial blood
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vIf abnormal result, another scalp blood sample is
collected immediately and the mother is taken to the
OR and prepared for surgery
vPrompt delivery is performed if the abnormal pH
and/or lactate level is confirmed
vThe only benefit reported for scalp blood pH or
lactate testing is
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v Record Keeping in a dark brown envelope
hDate and time
hWoman's name
hDate of birth/her age
hHospital number or NHS/MRN number
hThe woman's pulse rate at the start of monitoring
hOther clinical events and keep it as long as possible
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v Fetal scalp stimulation is a reliable alternative to scalp
blood pH determination
v Using of the fetal scalp or
v FHR acceleration in response to pinching the fetal scalp
with an Allis clamp just before obtaining blood is
v Failure to provoke acceleration not uniformly
predictive of fetal acidemia
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vRecommended as a substitute for fetal scalp blood sampling
vUses an electronic artificial larynx placed
approximately 1 cm from or directly onto the maternal
abdomen
vResponse is considered normal if a FHR acceleration of at
least 15 bpm for at least 15 seconds occurs within 15 seconds
after the stimulation and with prolonged fetal movements
vAn effective predictor of fetal acidosis in the setting of
variable and late decelerations
vDon’t predict neonatal outcome in 2nd stage labor
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vAllows assessment of fetal oxyhemoglobin saturation once
membranes are ruptured
vA unique padlike sensor is inserted through the cervix
and positioned against the fetal face
vThe transcervical device reliably registers fetal oxygen saturation
in 70 to 95 % of women throughout 50 to 88 % of their labors
vSaturation values <30 percent were associated with a greater risk
of potential fetal compromise when persistent for 2 min or
longer
vNellcor N-400 Fetal O2 Monitoring System approved by FDA
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vA normal fetus has a T/QRS < 0.25%
vA mature fetus exposed to hypoxemia develops an
elevated ST segment and a progressive rise in the T-
wave height that can be expressed as a T:QRS ratio
vFurther worsening of hypoxia leads to progressively
negative ST-segment deflection that takes on a biphasic
form
vST-segment abnormalities might occur late in the course
of fetal compromise
vST segment changes reflect myocardial tissue hypoxia
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vAbnormal Doppler waveforms may signify
pathological umbilical-placental vessel
resistance
vA poor predictor of adverse perinatal outcomes
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vThe dynamic nature of reassuring and non reassuring
fetal status during labor warrants close follow up
vThese assessments are subjective clinical judgments
that are inevitably subject to imperfection
vObvious Interobserver and intraobserver variation
vUsing three-tier FHR Interpretation System
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v ACOG adopts the 3 tier system of interpretation
developed by NICHD
vA color coded five tier system for both FHR
interpretation and management recommended by
JSOG
vSo far there is not strong consensus on interpretation
and management recommendations for FHR patterns
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1. Clinical picture
2. Cumulative uterine activity
3. Cycling of FHR
4. Central organ oxygenation
5. Catecholamine surge
6. Chemoreceptor or baroreceptor decelerations
7. Cascade of hypoxia
8. Consider the NEXT change on the CTG trace
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vComplicates 12 to 22 percent of labors
vFound to be a low risk obstetrical hazard in Parkland
hospital because the PMR attributable to meconium was
only 1 death per 1000 live births
vCan be explained by three theories regarding fetal
passage of meconium:
I. Fetuses may pass meconium in response to hypoxia
II. Represent normal GIT maturation under neural control
III. Following vagal stimulation from common but transient UC
entrapment with resultant increased bowel peristalsis
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 A Standardized “ABCD” Approach to
Abnormal FHR Management:
1) Assess the oxygen pathway
2) Begin corrective measures as indicated
3) Clear obstacles to rapid delivery
4) Determine decision to delivery time
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1)
2)
q The most common amnioinfusion protocol is to provide 500 to
800 ml bolus of warmed NS followed by continuous infusion of
3ml/min
q Can be used for:
v Treatment of variable or prolonged decelerations
v Prophylaxis for women with oligohydramnios as with
prolonged ruptured membranes and
v Attempts to dilute or wash out thick meconium
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v ACOG concluded that amnioinfusion is a reasonable approach
in the treatment of repetitive variable decelerations
regardless of meconium status
v ACOG does not recommend amnioinfusion to dilute meconium-
stained amnionic fluid
v NICE donot recommend amnioinfusion for intrauterine fetal
resuscitation
3)
4) Oxygen adminstration 10Lt with facemask
5)
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qAtleast 10 minutes of prolonged deceleration was required before
there was evidence of brain damage in surviving fetuses
qACOG recommended UC blood gases analysis when C/D
is performed for:
ØFetal compromise, IUGR
ØAbnormal FHR tracing, Intrapartum fever
ØMaternal thyroid disease, Multifetal gestation and/or
Ø Low 5-minute Apgar score following delivery
qReducing brain To after an inciting event reduce the incidence of
cerebral damage
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vThe temporal increase in fetal monitoring use was
associated with a decline in neonatal mortality rates
vThe PPV of EFM for fetal death in labor or cerebral
palsy is near zero
vHas better NPV
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vAccurate monitoring of uterine contractions
vSignificant improvement of perinatal mortality
vCan detect hypoxia early and can explain the
mechanism of hypoxia and its specific treatment
vImprovement of intrapartum fetal death by 3x
vIt is an important afidavit for medicolegal purpose
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1) Intra- and interobserver error; doubling or halving of FHR
2) Due to error of interpretation, high C/section rate
3) Instruments are expensive and trained personnel are required
4) Mother has to be confined in bed
5) Is a screening test that detects transient intrapartum
interruption of fetal oxygenation
6) Erroneous Monitoring of MHR as FHR
7) Loss of Contact or Poor Signal Quality
8) Incorrect Placement of Thermosensitive Paper
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vIntermittent auscultation or continuous EFM is
considered an acceptable method of intrapartum
surveillance in both low and high risk pregnancies
vThe recommended interval between checking the FHR is
longer in the uncomplicated pregnancy
vAt Parkland Hospital, all high-risk labors are continuously
monitored electronically

vAmnionic fluid pressure is measured between and during
contraction with internal monitoring of contractions
vIUP catheters are used that have the pressure sensor in
the catheter tip
vWith external monitoring, uterine contractions can be
measured by a displacement transducer in which the
plunger is held against the maternal abdominal wall
vInternal monitoring provided a more accurate
measure of intensity
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vMontevideo Units: uterine performance is the product
of contraction intensity in mm Hg multiplied by the
number of contractions in a 10minute span
vUterine activity is relatively quiescent during the first 30
weeks of pregnancy
vUx activity is enhanced during the last weeks of
pregnancy
vLabor commences when uterine activity reaches values
between 80 and 120 Montevideo units
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vUx contractions are clinically palpable only after their intensity
exceeds 10 mm Hg
vPainless until their strength ≥15 mm Hg
vMinimum IUP required to distend the lower uterine segment and
cervix
In first-stage labor
ü Uterine contractions progressively grow in intensity from ≈ 25 mm
Hg at labor commencement to 50 mm Hg at its end
ü Frequency advances from 3 to 5 contractions per 10 minutes
ü Uterine baseline tone rises from 8 to 12 mm Hg
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In 2nd stage
Ø
Ø
Ø
Ø
vMost women achieved 200 to 225 MVU and in 40
percent of women had up to 300 units to effect delivery
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vThe duration of uterine contractions of 60 to 80 seconds
does not lengthen appreciably from early active labor through
the second stage
vThis duration constancy serves fetal respiratory gas exchange
vRespiratory gas exchange is halted during uterine contraction as
the IUP exceeds that of the intervillous space
vThis leads to functional fetal breath holding
vThe clinicians demands on the uterus???
vThe uterus that performs poorly before delivery is also prone to
atony and PPH
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vThe pacemaker theory
vThe right pacemaker usually predominates over the left
and starts most contractile waves
vContractions spread from the pacemaker area throughout
the uterus at 2 cm/sec and the whole organ is
depolarized within 15 seconds
vIntensity is greatest in the fundus and it diminishes in the
lower uterus
vThis descending pressure gradient serves to direct fetal
descent toward the cervix and to efface the cervix
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qNormal uterine activity is defined as five or fewer
contractions in 10 minutes, averaged during a 30-minute
span
qTachysystole is more than five contractions in 10 minutes,
averaged over 30 minutes
ØTachysystole can be applied to spontaneous or induced labor
ØMost significantly associated with FHR decelerations
qThe term hyperstimulation is currently abandoned
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ØInjury to the fetal scalp, vessels, placenta and uterine
perforation
ØAscending infection and cranial osteomyelitis
ØCord compression
ØSpurious recording
üMaternal human immunodeficiency virus (HIV)
üHerpes simplex virus (HSV) and
üHepatitis B, C, D and E virus
üSignificant meconium and maternal sepsis
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Summary Qn ❶
Which setting is most appropriate for fetal vibroacoustic
stimulation:
A. 38 weeks, active labor, FHR baseline 140 beats per minute, minimal
variability, no accelerations, no decelerations
B. 40 weeks, active labor, FHR baseline 150 beats per minute, moderate
variability, prolonged deceleration to 60 beats per minute for 8 minutes
C. 39 weeks, active labor, FHR baseline 115 beats per minute, minimal
variability, frequent accelerations, occasional late decelerations
D. 35 weeks, frequent contractions without cervical change, FHR baseline
180 beats per minute, moderate variability, frequent accelerations,
frequent late decelerations
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Summary Qn ❷
Category II tracing
A. Predicts abnormal fetal acid-base status
B. Excludes abnormal fetal acid-base status
C. Is not predictive of abnormal fetal acid-base status
D. Is always predictive of normal feta acid-base status
E. None of the above
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Try to comment FHR Pattern to Physiology!
And
Never Ever try to comment just Patterns!!
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1. Williams Obstetrics, 25th edition-Intrapartum assessment (Chapter 24 P-1001 to 1065)
2. DC Dutta’s Text book of Obstetrics, 8th edition-Special topics in Obstetrics (Chapter 39
P-692 t0 698)
3. Gabbe’s Obstetrics Essentials, 8th edition-Intrapartum Fetal Evaluation (Chapter 15 P-
272 to 289)
4. Review of the 2008 NICHD Research Planning Workshop: Recommendations for FHR
Terminology and Interpretation
5. NICE Clinical Guideline on Intrapartum care for healthy women and babies(NICECG190)
6. FIGO Consensus Guidelines on Intra-partum Fetal Monitoring-2015
7. Handbook of CTG interpretation from patterns to Physiology-Cambridge University
Press 2017
8. ACOG Practice Bulletin No-106: Intra-partum Fetal Heart Rate Monitoring
9. Electronic Fetal Monitoring: Past, Present and Future-doi:10.1016/j.clp.2010.12.002
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Intrapartum fetal monitoring

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