Anesthesia Student Survival Guide.pdf - Index of

PhysiOlOGy And AnesthesiA FOr OBstetriCs ● 311
Apgar Score of the newborn. The score ranges from 0 to 10, with 7–10 generally
considered normal.
Anesthesia for Vaginal Delivery
The coordinated uterine movements and cervical dilation cause significant
discomfort commonly known as labor pain. Labor itself can be divided into
three stages:
● the first stage of labor begins with contractions and ends with complete
cervical dilatation
● the second stage of labor begins with full cervical dilation and ends when
the fetus is delivered
● the third stage of labor begins with the delivery of the fetus and ends with
delivery of the placenta
The majority of pain during the latent phase of labor is visceral in quality
and uterine in origin. During the first stage of labor, pain is due to cervical
dilatation and uterine contractions. The pain pathway involves visceral afferents
that enter the spinal cord at T10-L1. As labor progresses to second stage, it is
increasingly accompanied by somatic pain, which reaches the spinal cord via
pudental afferents (S2–S4). Fig. 19.5 depicts pain pathways in the parturient.
T
L
S
10
11
12
1
2
3
4
Figure 19.5 Pain pathways for the first and second stages of labor. (From Datta, S. Obstetric
Anesthesia Handbook, 4th ed. Springer, 2006).