Fetal Heart Monitoring Dr. Moulton

Question 1

External Electronic Fetal Heart Monitoring 2 devices

Answer 1

1. Doppler US transducer = records sound waves from fetal heart
2. Pressure Sensitive Tocodynanmometer transducer = defects contractions (f of contractions) , + fetal response to it (can be off if mother is obese)
   = does NOT reduce cerebral palsy cases

Question 2

Internal Electronic Fetal Heart Monitoring 2 devices

Answer 2

1. Fetal Scalp Electrode (FSE) =rupture through sac and screw on to baby’s head, accurate Heart monitoring
2. Intrauterine Pressure Catheter (IUPC : catheter placed giving STRENGTH of contractions

= membrane is ruptured in both, more accurate

Question 3

O2 to baby during contractions

1. What determines fetal HR
2. PH in hypoxia

Answer 3

Is interrupted, so if there is good oxygenation between contractions then baby wound have hypoxia = hypoxia in fetus will build up lactic acid and get acidosis (contractions effect fetal HR)

1. Atrial pacemaker
2. PH = 7.25-7.30 normal, pH = under 7.20 is hypoxia

Question 4

Fetal Monitoring Strip is set up how

Answer 4

1. Top line is fetal HR
2. Bottom line is Contractions in uterus

= 1 small box is 10sec across and 10beats up, 1 big box is 1min

Question 5

Normal uterine contractions

Tachysystole uterine contractions

Answer 5

1. Normal = 5 Contractions or less in 10min (average in 30min)
2. Tachysystole = more then 5 contractions in 1min (average in 30min) (check for decelerations )

Question 6

Montevideo Units (MVUs)

1. What is this
2. How can you get this

Answer 6

1. Sum of all contraction strengths in 10min for at least 2hrs
2. IUPC
3. Over 200, then dont continues giving pitocin (if still not ready to deliver then another of the 3Ps is the problem)

Question 7

Fetal HR is normal, tachy, and Brady

Answer 7

1. Normal = 110-160
2. Tachycardia = over 160
3. Bradycardia = under 110

Question 8

Things that can cause fetal Bradycardia

Answer 8

1. Fetal Hypoxia - late sign
2. Anesthesia or Pitocin
3. Maternal Typotension
4. Compressed umbilical cord
5. Heart block

Question 9

Reasons for fetal tachycardia

Answer 9

1. Fetal hypoxia (early sign)
2. Oxytocin (excessive)
3. Arrhythmia
4. Prematurity
5. Maternal Fever
6. Fetal Infection**

Question 10

Variability in Fetal HR

Answer 10

Peak to most bottom on the fetal strip

1. Absent = no range
2. Minimal = less then 5bpm
3. Moderate = NORMAL from 6bpm-25bpm**
4. Marked = over 25bpm

Question 11

cause of low HR variability of fetus

Answer 11

Usually from hypoxia leading to acid environments

1. Prematurity
2. Sleep
3. Maternal Fever
4. Fetal Tachycardia
5. Hyperthyroidism mother
6. Mother illicit drugs, fetal congenital anomalies

Question 12

Acceleration in fetal HR means what

Answer 12

Abrupt increase in HR (normal)

1. If over 32 weeks = 15bpm over baseline for 15sec -2min
2. Less then 32 weeks = 10bpm over baseline for 10sec-2min

Question 13

Prolonged acceleration vs change in baseline

Answer 13

1. Prolonged = over 2min

2. Change in baseline = over 10min

Question 14

Causes of accelerations

Answer 14

1. Fetal movement
2. Scalp stimulaiton or vibroacustic stimulation
3. Vaginal examination

Question 15

Decelerations are what

Answer 15

Decrease in Fetal HR after a contraction

= early, variable, late

Question 16

Early Decelerations

Answer 16

GOOD
= secondary to head compression (increased intracranial P —> lower BF—> activated central vagus N —> lower HR)
= happens at the same time as contraction

Question 17

Variables Decelerations happen how and means

Answer 17

Can be good or bad

1. Secondary to Umbilical cord compression (especially after rupture)
2. Can happen before during or after contraction (sharp peaks usually more then 15bpm down)

Question 18

Late decelerations means what and happens when

Answer 18

1. bad
2. Uterine placental insufficiency (UPI)
   = fetal acidosis, low arterial pH
   = after the contractions

Question 19

Prolonged Decelerations are what and means

Answer 19

1. HR decrease more the 15bpm for over 2min -10min

2. O2 disruption to fetus (usually during maternal pushing)

Question 20

Sinusoidal Pattern of fetal HR means what and happens when

Answer 20

1. not good
2. Fetal anemia need EM c-section useless giving birth
   = curve goes up and down like a sine curve

Question 21

Category 1 pregnancy means

Answer 21

Baby will do good

1. HR 110-160
2. Moderate variability
3. Early decelerations + accelerations can be present

Question 22

Category 2 pregnancy means

Answer 22

Baby can do fine

1. Variable decelerations (less the 50% of them) = baby is fine
2. Variable decelerations (more then 50%) = umbilical cord compression , acidemia —-> modify how mom sits, aminoinfusion, stop pushing for a bit
3. No variability = improve oxygenation , position mom to left recumbent

Question 23

Amnioinfusion is what

Answer 23

Normal Saline through IUPC to prevent cord compression

Question 24

Category 3 what to do

Answer 24

bad things you see, fetus can not do that fine
1. Recurrent late decelerations
2. Bradycardia
3. Sinusoidal pattern
4. Recurrent variable decelerations (over 50%)
= prepare for delivery, O2, IV saline, scalp stimulation, reposition mother

Question 25

EM C-section how many minutes do you have to get baby out

Answer 25

30min

Question 26

Spontaneous rupture happens and baby has no variability and 50HR what do you do

Answer 26

When where cord is, reposition mom, ask if pitocin has been started , if nothing helps = EM c- section

Question 27

Reactive Stress Test what (GOOD STRESS TEST)

Answer 27

15bpm above base line lasting 15sec , 2 times within 20min

Question 28

Fetal HR for compression umbilical cord

Answer 28

Variable decelerations Prolonged deselection Fetal Bradycardia