Bl. Leighton et al., Lumbar sympathetic blocks speed early and second stage induced labor in nulliparous women, ANESTHESIOL, 90(4), 1999, pp. 1039-1046
Citations number
24
Categorie Soggetti
Aneshtesia & Intensive Care","Medical Research Diagnosis & Treatment
Background Rapid cervical dilation reportedly accompanies lumbar sympatheti
c blockade, whereas epidural analgesia is associated with slow labor. The a
uthors compared the effects of initial lumbar sympathetic block with those
of epidural analgesia on labor speed and delivery mode in this pilot study.
Methods: At a hospital not practicing active labor management, full-term nu
lliparous patients whose labors were induced randomly received initial lumb
ar sympathetic block or epidural analgesia. The latter patients received 10
mi bupivacaine, 0.125%; 50 mu g fentanyl; and 100 pg epinephrine epidurall
y and sham lumbar sympathetic blocks. Patients to have lumbar sympathetic b
locks received 10 mi bupivacaine, 0.5%; 25 mu g fentanyl; and 50 mu g epine
phrine bilaterally and epidural catheters, Subsequently, all patients recei
ved epidural analgesia.
Results: Cervical dilation occurred more quickly (57 is, 120 min/cm cervica
l dilation; P = 0.05) during the first 2 h of analgesia in patients having
lumbar sympathetic blocks (n = 17) than in patients having epidurals (n = 1
9). The second stage of labor was briefer in patients having lumbar sympath
etic blocks than in those having epidurals (105 vs. 270 min; P < 0.05). Nin
e patients having lumbar sympathetic block and seven having epidurals deliv
ered spontaneously, whereas seven patients having lumbar sympathetic block
and seven having epidurals had instrument-assisted vaginal deliveries. Cesa
rean delivery for fetal bradycardia occurred in one patient having lumbar s
ympathetic block. Cesarean delivery for dystocia occurred in five patients
having epidurals compared with no patient having lumbar sympathetic block (
P = not significant). Visual analog pain scores differed only at GO min aft
er block.
Conclusions: Nulliparous parturients having induced labor and receiving ini
tial lumbar sympathetic blocks had faster cervical dilation during the firs
t 2 h of analgesia, shorter second-stage labors, and a trend toward a lower
dystocia cesarean delivery rate than did patients having epidural analgesi
a. The effects of lumbar sympathetic block on labor need to be determined i
n other patient groups. These results may help define the tocodynamic effec
ts of regional labor analgesia.