Rr. Gaiser et al., COMPARISON OF 0.255-PERCENT ROPIVACAINE AND BUPIVACAINE FOR EPIDURAL ANALGESIA FOR LABOR AND VAGINAL DELIVERY, Journal of clinical anesthesia, 9(7), 1997, pp. 564-568
Study Objective: Part 1: To measure ropivacaine levels in the mother a
nd infant at delivery after continuous lumbar epidural infusion. Part
2: To compare epidural ropivacaine to epidural bupivacaine for labor a
nalgesia in regard to effectiveness, motor blockade, and maternal and
neonatal effects. Design: Part 1: Open-labelled, non-blind study. Part
2: Randomized, double-blind study. Setting: Labor and delivery units
of two academic hospitals. Patients: Part 1: 20 ASA physical status I
and II parturients in active labor. Part 2: 81 ASA physical status I a
nd II parturients in active labor. Interventions: For Part 1, 8 to 12
ml of 0.25% ropivacaine was administered through a lumbar epidural cat
heter to achieve a T-10 dermatomal sensory level. An infusion of 0.25%
ropivacaine, 8 to 10 ml/hr, maintained this sensory level. Maternal a
nd umbilical cord blood samples obtained at delivery were analyzed for
ropivacaine concentration. For Part 2, anesthetic management was simi
lar to that previously described except patients were randomized to re
ceive either 0.25% ropivacaine or 0.25% bupivacaine. Onset, regression
, maximal spread of sensory block, and onset and degree of motor block
age were measured. Contraction pain as assessed using a visual analog
scale (VAS), maternal blood pressure, and heart rate were determined e
very 5 minutes until a stable VAS-contraction score was achieved, and
every 30 minutes thereafter. Neonatal assessment included Apgar scores
and neurologic and adaptive capacity scores (NACS) at 15 minutes, 2 h
ours, and 24 hours. Measurements and Main Results: For Part 1, the tot
al and free maternal arterial concentrations of ropivacaine at deliver
y were 0.64 +/- 0.14 mu g/ml and 0.10 +/- .02 mu g/ml, respectively; t
he umbilical venous total and free concentrations were 0.19 +/- 0.03 m
u g/ml and 0.12 +/- 0.07 mu g/ml, respectively (n = 12). The umbilical
arterial and venous concentrations did not differ for both the free a
nd total concentrations. For Part 2, there was no difference between r
opivacaine and bupivacaine in the variables measured. Umbilical cord g
ases and Apgar scores were not different between the two groups; NACS
were higher at 15 minutes and 2 hours in the ropivacaine group (p < 0.
05) than the bupivacaine group. Conclusion: Both ropivacaine and bupiv
acaine produced excellent analgesia for labor with no major adverse ef
fect on the mother or neonate. (C) 1997 by Elsevier Science Inc.