Local anesthetic requirements are greater in XXXX than in normal labor.

@entity1 @entity398 @entity1266 @entity409 @entity1337 @entity1341 @entity158
BACKGROUND: @entity1266 is characterized by abnormal progress of labor and is a common contemporary indication for cesarean delivery in the United States. There has been considerable controversy as to whether @entity409 leading to cesarean delivery for @entity1266 . The minimum local analgesic concentration (MLAC) is a clinical model used to determine the relative potencies of local anesthetics in the first stage of labor. In this article, the authors report a prospective study determining the MLAC of @entity1341 in early labor of parturients who eventually delivered either vaginally or via cesarean section. METHODS: An up-down sequential allocation technique was used to determine the MLAC of @entity1341 in 57 nulliparous parturients assigned to either vaginal delivery or cesarean section arms. In addition, @entity1 were assigned to groups receiving or not receiving intravenous @entity398 at the time of epidural placement. Only @entity1 who delivered by the assigned delivery mode were included in the MLAC analyses. RESULTS: Parturients who later delivered vaginally had 25% and 31% lower MLAC values (0.078% and 0.085% wt/vol @entity1341 , receiving or not receiving intravenous @entity398 , respectively) than those who later delivered by cesarean section (0.102% and 0.106% wt/vol @entity1341 , receiving or not receiving intravenous @entity398 , respectively). CONCLUSIONS: These data suggest that an increased local anesthetic requirement for epidural labor @entity1337 is associated with more @entity158 related to @entity1266 . @entity1 in early, clinically normal labor but who later develop @entity1266 require more local anesthetic and, by inference, are experiencing more severe @entity158 than @entity1 who deliver vaginally. This association should be considered when studying the relation between the method of labor @entity1337 and the course of labor.
