Anesthesia techniques: 1st stage labor
- Variable duration
- Starts at onset of labor
- Complete when the rate of cervical dilation increases (~ 3 cm)
- acceleration phase
- phase of maximal slope
- deceleration phase
Normal active labor should progress 1 cm/hr Most common measure of uterine activity is the Montevideo unit (avg intensity frequency per 10 minutes)
Stage II : interval between maximal dilation and delivery (20-120 mins)
Stage III : placental delivery (5-20 mins)
In the first stage of labor, pain travels via sympathetic nerve fibers (going through the inferior hypogastric plexus on the way to the sympathetic chain) that originate from the T10-L1 segments of the spinal cord (referred to the back as well as abdominal wall).
Common techniques include systemic medication administration (single doses of < 1 ucg/kg or lower appear to have no effects on fetal APGAR scores).