PB 116: Management of intrapartum fetal heart rate tracings Flashcards
Definition of normal uterine activity vs. tachysystole?
Normal: 5 or fewer contractions in 10 minutes over a 30 minute period
Tachysystole: >5 contractions in 10 minutes over a 30 minute period
Definition of baseline HR?
Rate for a minimum of 2 minutes over a 10 minute period
Moderate variability is?
6-25 bpm
Definition of accelerations?
Increase in FHR that is <30s from onset to peak and lasting <2 minutes
Rise has to be 15x15 if >32w, 10x10 if <32w
How do early and late decels differ from variables?
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
Definition of “prolonged” accel or decel?
> 2min but <10 min
What is a FHR sinusoidal pattern?
FHR rapidly cycles - have 3-5 up and down cycles per minute persisting for 20+ minutes
What are “recurrent” variables?
Occur with >50% of contractions; caused by cord compression
What can cause late decelerations?
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
What makes category III tracings different from category II?
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
Dr. Linder’s order for fetal resuscitation in response to a bad strip?
Bad strip: big decel
- Watch for 2 min - it may still resolve
- 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)
- 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
- In 8-10 min - roll back to OR for stat section
How often should you be reviewing a Category I strip?
Every 30 min in first stage of labor, every 15 min in second stage
How can you help promote fetal oxygenation and improve uteroplacental blood flow?
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
Techniques to reduce uterine activity?
Tachysystole with category II or III tracing: IVF bolus, d/c oxytocin or cervical ripening agents, administer tocolytic meds (e.g. terbutaline)
Techniques to alleviate umbilical cord compression?
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
