INTRA-PARTUM MONITORING

Vaginal Exam   membrane status  cervical effacement (thinning), dilatation, consistency, position, application  fetal presenting part...

Vaginal Exam 

1. membrane status 
2. cervical effacement (thinning), dilatation, consistency, position, application 
3. fetal presenting part, position, and station 
4. bony pelvis size and shape

Intrapartum Fetal Cardiotocography (CTG)

• external (doppler) vs. internal (scalp electrode) monitoring
• describe in terms of baseline FHR, variability (short term, long term) and periodicity(accelerations, decelerations)

• baseline FHR

normal range is 120-160 bpm
a parameter of fetal well-being vs. distress 

• variability

1. short term - beat to beat (requires scalp monitor)
2. long term - described with respect to frequency and amplitude of change in baseline
3. frequency is defined as number of times in a 1 minute period with an increase or decrease of at least 5 bpm lasting 5 seconds (average frequency is 3)
4. amplitude is based on difference between highest and lowest FHR within a 1 minute period (11-25 bpm is average)

periodicity

• accelerations

excursion of 15 bpm or more lasting for at least 15 seconds, in  response to fetal  movement or uterine contraction

• decelerations

describe in terms of shape, onset, depth, duration, recovery, occurrence, and impact on baseline FHR and  variability

• early decelerations

1. uniform shape with onset early in contraction, returns to baseline by end of contraction; slow gradual deceleration
2. often repetitive, no effect on baseline FHR or variability
3. due to vagal response to head compression
4. benign, usually seen with cervical dilatation of 4-7cm

• variable decelerations

1. most common type of periodicity seen during labour
2. variable in shape, onset and duration
3. may or may not be repetitive
4. often with abrupt rapid drop in FHR, usually no effect on baseline FHR or variability
5. due to cord compression or, in second stage, forceful pushing with contractions
6. benign unless repetitive, with slow recovery, or when associated with other abnormalities of FHR

• late decelerations

1. uniform (symmetric) in shape, with onset late in contraction, lowest depth after peak of contraction, and returns to baseline after end of contraction
2. may cause decreased variability and change in baseline FHR
3. must see 3 in a row, all with the same shape to define as late deceleration
4. due to fetal hypoxia and acidemia, maternal hypotension, or uterine hypertonus
5. usually a sign of uteroplacental insufficiency (ominous)
6. manage with position change to left lateral decubitus,oxygen, stopping oxytocin, C/S

Approach to Abnormal FHR

1. if external monitor, ensure fetal tracing and not maternal
2. change position of mother
3. give 100% oxygen by mask and discontinue oxytocin
4. rule out cord prolapse consider fetal scalp electrode to assess beat-to-beat variability and fetal scalp blood sampling if abnormality persists
5. immediate delivery if recurrent prolonged bradycardia

Fetal Scalp Blood Sampling

1. indicator of fetal distress
2. > 7.25 pH is normal
3. < 7.25 indicates that test should be repeated in 30 minutes
4. < 7.20 indicates fetal acidosis severe enough to warrant immediate delivery

Meconium in the Amniotic Fluid

1. usually not present early in labour
2. may occur prior to ROM or after rupture has occurred with passage of clear fluid
3. classified as thick or thin
4. thin meconium appears as a lightly stained yellowish or greenish fluid
5. thick meconium appears dark green or black and may have pea-soup

consistency

• associated with lower APGARS and increased risk of meconium aspiration
• call pediatrics to delivery
• may indicate undiagnosed breech

    6.   increasing amount during labour may be a sign of fetal distress

---

"It will take only 2 sec to say thanks and will take only 10 sec to write a comment it will be a nice encouragement for uploaders "

---