PB 116: Management of intrapartum fetal heart rate tracings Flashcards Preview

Practice bulletins > PB 116: Management of intrapartum fetal heart rate tracings > Flashcards

Flashcards in PB 116: Management of intrapartum fetal heart rate tracings Deck (19)
Loading flashcards...
1
Q

Definition of normal uterine activity vs. tachysystole?

A

Normal: 5 or fewer contractions in 10 minutes over a 30 minute period

Tachysystole: >5 contractions in 10 minutes over a 30 minute period

2
Q

Definition of baseline HR?

A

Rate for a minimum of 2 minutes over a 10 minute period

3
Q

Moderate variability is?

A

6-25 bpm

4
Q

Definition of accelerations?

A

Increase in FHR that is <30s from onset to peak and lasting <2 minutes

Rise has to be 15x15 if >32w, 10x10 if <32w

5
Q

How do early and late decels differ from variables?

A

Early (head compression, nadir matches peak of contraction) and late (placental insufficiency, starts after contraction) are GRADUAL with 30s or more between onset to the beginning of the decel’s nadir

Variable decels are abrupt with onset to the beginning of nadir lasting <30s and decreasing 15x15 at least

6
Q

Definition of “prolonged” accel or decel?

A

> 2min but <10 min

7
Q

What is a FHR sinusoidal pattern?

A

FHR rapidly cycles - have 3-5 up and down cycles per minute persisting for 20+ minutes

8
Q

What are “recurrent” variables?

A

Occur with >50% of contractions; caused by cord compression

9
Q

What can cause late decelerations?

A

Transient or chronic uteroplacental insufficiency: maternal hypotension (e.g. postepidural), uterine tachysystole, maternal hypoxia

Late decels have low predictive value for acidemia and a high false-positive rate for fetal neurological injury

10
Q

What makes category III tracings different from category II?

A

Must have ABSENT variability

Category II tracings with moderate variability and accels are highly predictive of a normal fetal acid-base status even with recurrent variables and lates

11
Q

Dr. Linder’s order for fetal resuscitation in response to a bad strip?

A

Bad strip: big decel

  1. Watch for 2 min - it may still resolve
  2. Reposition (can move baby off cord or mom’s IVC), fluid bolus (can help alleviate tachysystole, provide more circulating fluid), oxygen (gives baby O2 bolus by boosting circulating oxygen), check cervix (baby’s head may have come down, cord prolapse)
  3. In 4-5 min - stop pitocin if on, ask for terb in the room, ask for ultrasound to scan baby’s heart -> give terbutaline (0.25 mg) if stopping pitocin not helpful - takes 2 min or so to work
  4. In 8-10 min - roll back to OR for stat section
12
Q

How often should you be reviewing a Category I strip?

A

Every 30 min in first stage of labor, every 15 min in second stage

13
Q

How can you help promote fetal oxygenation and improve uteroplacental blood flow?

A

Recurrent late decels: initiate lateral positioning

Prolonged decels or bradycardia: administer oxygen (increases baby’s oxygen reserve)

Minimal or absent FHR variability: give IVF bolus - can reduce uterine contraction frequency if baby is stressed by tachysystole

14
Q

Techniques to reduce uterine activity?

A

Tachysystole with category II or III tracing: IVF bolus, d/c oxytocin or cervical ripening agents, administer tocolytic meds (e.g. terbutaline)

15
Q

Techniques to alleviate umbilical cord compression?

A

Recurrent variable decels: initiate maternal repositioning

Prolonged decels or bradycardia: if ruptured can place IUPC and initiate amnioinfusion; check cervix and if prolapsed cord is noted, elevate head and prep for operative delivery

16
Q

What is fetal tachycardia and how do you treat it?

A

FHR > 160 bpm

Evaluate for underlying causes → infection (chorioamnionitis, pyelonephritis, etc.), medications (terbutaline, cocaine, other stimulants), maternal medical disorders (hypothyroidism), obstetric conditions (placental abruption, fetal bleed), fetal tachyarrhythmias (FHR often >200 bpm in those cases) → treat underlying cause

17
Q

What is considered intrapartum bradycardia and what is the ddx?

A

Bradycardia: <110 bpm for 10 minutes

Underlying causes → maternal hypotension (postepidural), umbilical cord prolapse or occlusion, rapid fetal descent, tachysystole, placental abruption, or uterine rupture

18
Q

What is minimal variability and what causes it?

A

Minimal: <5 bpm variability

Potential causes → maternal opioid administration (should return to moderate in 1-2h), mag sulfate, fetal sleep cycle (20-60 min with return to moderate afterwards), fetal acidemia (which requires resuscitation maneuvers)

19
Q

What are the serious associations with category III tracings and what is the timeline for delivery when you see one?

A

Associated with increased risk of neonatal encephalopathy, cerebral palsy, neonatal acidosis

No acceptable time frame for going from Category III tracing to delivery is agreed on - colloquially 30-minute rule from decision-to-incision time has existed but evidence does not support that waiting longer increases risks of adverse neonatal outcomes