Obstetrics Flashcards
(20 cards)
What are the three types of fetal deceleration phenomena?
Early, late, and variable
What causes early decelerations?
Head compression
Uterine contractions compress the fetal head, increasing vagal tone.
How does the timing of early decelerations relate to uterine contractions?
Onset and offset parallels uterine contraction
What is the heart rate change associated with early decelerations?
HR < 20 bpm from baseline
Is there a risk of fetal hypoxemia with early decelerations?
No risk
What condition leads to late decelerations?
Uteroplacental insufficiency
What is the pattern of FHR in late decelerations?
FHR falls after peak of contraction then returns to baseline after contraction
What causes late decelerations?
Maternal hypotension, hypovolemia, acidosis, preeclampsia
Is there a risk of fetal hypoxemia with late decelerations?
Yes, requires urgent assessment of fetal status
What is the cause of variable decelerations?
Umbilical cord compression
What is the relationship between FHR and uterine contractions in variable decelerations?
No consistent pattern
What effect does umbilical compression have on FHR?
Baroreceptor mediated reduction in FHR
Are variable decelerations usually self-limiting?
Yes
What happens to FHR variability during variable decelerations?
Maintains variability during deceleration
Is there a risk of fetal hypoxemia with variable decelerations?
Yes, requires urgent assessment of fetal status
What mnemonic can be used to remember the types of decelerations and their causes?
VEAL CHOP
What does ‘V’ in VEAL CHOP stand for?
Variable decels: Cord compression
What does ‘E’ in VEAL CHOP stand for?
Early decels: Head compression
What does ‘A’ in VEAL CHOP stand for?
Accelerations: OK or give oxygen
What does ‘L’ in VEAL CHOP stand for?
Late decels: Placental insufficiency
