Fetal Heart Monitoring - Moulton

Question 1

***2 external monitors on the external abdomen for fetal monitorint

Answer 1

Doppler ultrasound transducer – sound waves of heart

Pressure-sensitive tocodynanmometer – FREQUENCY of contractions (NOT strength)

Question 2

How to measure STRENGTH of contractions?

Answer 2

Intrauterine pressure catheter (IUPC)

Question 3

What is fetal scalp electrode (FSE)?

Answer 3

Internal way to monitor fetal EKG – screw it into baby’s skull

Question 4

Fetal scalp pH less than 7.2…means what?

Answer 4

Baby is hypoxic (due to anaerobic metabolism, causing metabolic acidosis)

Question 5

How does fetal heart rate change w/ uterine contractions?

Answer 5

Contraction causes myometrial vessel compression, baby gets hypoxic, increases HR

Question 6

• ***Fetal monitoring strip…
  
  • Each big vertical line?
  • Upper tracing?
  • Lower tracing?

Answer 6

1 minute

Fetal heart rate over time

Uterine pressure (contractions) over time

Question 7

***Baseline (middle horizontal line) in upper fetal strip?

***Each small line above/below?

Answer 7

120 bpm

+/- 10 bpm

Question 8

***Normal uterine contraction rate

Tachysystole?

Answer 8

5 or less in 10 minutes, averaged over 30 minutes

More than 5 in 10 minutes, averaged over 30 minutes

Question 9

***Given an IUPC strip (Montevideo units - MVUs)…how to know if contractions are strong enough for cervical change?

Answer 9

Add heights of all the contraction peaks together - over the course of every 10 minutes

Must be > 200 for at least 2 hrs

Question 10

***Normal range of fetal heart rate

Answer 10

110 - 160

Question 11

NORMAL (moderate) variability in fetal heart rate baseline

Measured how?

Answer 11

+/- 6-25 from that baby’s normal

Peak to trough as it fluctuates

Question 12

***What are the possible changes in fetal heart rate over time? (including sub-categories)

Answer 12

• No change
• Acceleration
  
  • Prolonged = >2 min
  • Baseline ∆ = > 10 min
• Deceleration
  
  • Early, variable, late
  • Prolonged

Question 13

***Types of FHR decelerations (3) - explain each

Answer 13

Early (mirrors contractions – from head compression - high ICP) - GOOD

Variable (abrupt, random, due to cord compression) - 15+ for 15+ minutes for under 2 min - from umbilical vein compression

Late (after peak of contraction – due to uteroplacental insufficiency – BAD if repetitive – means acidosis)

Question 14

Sinusoidal pattern of FHR - means what?

Answer 14

Severe fetal anemia - BAD

Question 15

***Recurrent variable decelerations – defined as what?

***Should do what? How? Why?

Answer 15

Variable decel’s in >50% of contractions

Amnioinfusion through the IUPC – to avoid acidemia

Question 16

FHR strip shows reduced variability but no decelerations. What quick test can you do to test for acidemia?

Differentiates between what 2 fetal states?

Answer 16

Fetal scalp stimulation – will see acceleration (reactive) if pH is >7.2

Acidemia vs. sleep

Question 17

***Pregnant woman in labor is doing well. All of a sudden gets spontaneous rupture of membranes. FHTs go from 120s to 50s with no variability. Not fully dilated. What is happening?

Do what? (4)

If normal fixes don’t work, do what? How long does this take?

Answer 17

Cord compression

Stop any oxytocin, roll on L side, oxygen, check cervix

Emergent C-section - 30 min

Question 18

Pregnant woman in labor is doing well. All of a sudden gets spontaneous rupture of membranes. FHTs go down to 50s. Fully dilated…

Best way to deliver if possible?

Answer 18

Forceps

Quickest

Question 19

MOST babies that are showing non-reassuring FHR patterns are born (healthy/poor)

Answer 19

HEALTHY

Question 20

**Degrees of vaginal laceration

Answer 20

1st - vaginal mucosa
2nd - w/ some other perineum
3rd - anal sphincter
4th - rectal mucosa

Question 21

Category 1 FHR

Answer 21

Normal baseline w/ normal variability, no late or variable decels

Question 22

Category 3 FHR

Answer 22

Recurrent variable or late decels, no variability, sinusoidal pattern, bradycardia

Question 23

Category 2 FHR

Answer 23

Normal baseline, some variable decels