This stage of labor includes the onset of labor to complete cervical dilation.  This stage is also often subdivided into early (also called the latent phase), active, and transition stages. 

1) What stage am I?

2) How dilated is the cervix before transition to another stage?

3) What dermatomes are involved?

4) What is effective at relieving pain at this stage of labor?

1) Stage 1

2) 10 cm

3) T 10 to L1

4) An epidural

1) Which stage of labor starts with the cervix dilated to 10 cm and ends with delivery of a baby?

2) What causes most of the pain in this stage?

3) How can this pain be relieved?

1) Stage II

2) Stretching of the pelvic musculature and ligaments produces pain mediated by the sacral plexus (S2-S4).

3) This pain is often not covered by an epidural, but can be effectively relieved with a pudendal block.

1) What stage involves delivery of the placenta?

2) What dermatomes are involved?

1) Stage 3

2) T10 to L1  (sympathetic fibers)

1) Does Labor Epidural Anesthesia slow the progression of labor?

2) What does an unnecessarily dense block accomplish?

1) It is accepted that epidural anesthesia slows the latent phase but has little effect on the active phase of labor.

2) Impacts the progression of labor by eliminating the womans ability to bear down and push during the second stage.  Also-may knock out the motor fibers which also removes the ability to fully push.

1) What do we utilize to monitor fetal well being that is not a specific predictor but is the most readily available we have? 

2) What are the 2 types? Describe them.

1) Fetal HR monitor

2) Noninvasive: an abdominal ultrasound probe is aimed at the fetal heart and a probe is placed over the upper uterine wall. 

Invasive: Pressure catheter is slid beside the baby and a fetal scalp monitor is embedded 2mm into the baby's scalp.  This method requires a head down position, ruptured amniotic sac and slightly dilated cervix. 

1) The normal Fetal heart rate is what?

2) Fetal bradycardia to _______ bpm is generally well tolerated if it lasts less than 2 minutes?

3) Does a low gestational age fetus have a higher or lower heart rate?

4) When is fetal bradycardia deemed "severe"?

5) When is the fetal heart rate considered tachycardic?

1) 120-160

2) 100

3) higher

4) below 80

5) 160

1) What is the term used to describe changes in FHR?

It is the single best non-invasive clinical indicator of fetal well being.

1) How do we know if an infant is becoming hypoxic and acidotic? 

2) What meds/types of meds do we give moms that decrease FHR variability?

1) If an infant becomes hypoxic and acidotic this depresses the CNS which in turn would affect the vagal nerve which mediates beat to beat heart rate variation.   Therefore we would see a decrease in variability. 

2) Opiods and Magnesium

1) Fetal Heart rate slows and quickens in time with what?

2) Are early decelerations a cause for alarm?

3) With Early Decelerations the heart rate usually does not decrease more than?

4) What is the mechanism thought to produce early decelerations? 

5) Women who push too early against a less than fully dilated cervix can produce what?

1) Labor contractions

2) No. The fetus is responding properly to labor and delivery.

3) 20 Bpm

4) Compression of the fetal head as it passes through the birth canal is thought to be the cause of early decelerations via vagal stimulation.

5)  early decels.

1) Occur with each uterine contraction

2) Start and end with the contraction

3) Mild decrease in HR < 20 bpm

4) Loss in beat to beat variability only during contraction.

True or False regarding variable declerations:

1) They resemble the letters U, V, and W and may not bear a constant relationship to uterine contractions.

2) They are the rarely encountered patterns during labor

3) Occur frequently in patients who have experienced premature rupture of membranes and decreased amniotic fluid. 

4) Variable decelerations are caused by the approximation of the sutures of the fetal skull during the birthing process.

1) True

2) False:  Most commonly encountered patterns

3) True

4) False: compression of the umbilical chord

Regarding Variable Decelerations:

1) Pressure on the umbilical cord initially occludes the umbilical vein which then results in what?

2) Is this a healthy or unhealthy response? (regarding #1 above)

3) What happens after #1 above?

1) An acceleration (the shoulder of the deceleration)

2) This indicates a healthy response.

3) Occlusion of the umbilical artery which results in the sharp downslope (seen on the fetal monitor)

Tell me, if you will, about the recovery phase of of a variable deceleration.

2) What may follow the recovery phase?

1) Recover phase is d/t relief of compression on the cord and the sharp return to baseline.  

2) Recovery may be followed by another healthy brief acceleration or shoulder.

Tell me about the 4 main points (or outline) if you will,  variable decelerations: 

1) How is the appearance?

2) Is the onset fast or slow?

3) Beat to beat variability?

4) when is the decleration considered severe?

1) Varied appearance, depth and shape

2) Abrupt onset and recovery

3) Maintain beat to beat variability

4) Deceleration is considered severe if drop in HR by 60 bpm, or HR < 60 bpm or duration lasts longer than 60 seconds.