[Obstetric epidural analgesia: relationship between obstetric variables and the course of labor].
OBJECTIVE
To analyze the relationship between epidural analgesia and diverse obstetric and fetal variables as well as the impact of epidural analgesia on the rates of instrumental and cesarean delivery.


METHODS
Observational study of women who gave birth at Fundación Hospital Alcorcón over a period of 3 years. All the women were offered obstetric epidural analgesia based on 0.0625% bupivacaine plus 2 microg/mL of fentanyl. The following data were recorded: age, nulliparity (yes/no) administration of epidural analgesia (yes/no), induction of labor (yes/no), stimulation of uterine activity with oxytocin (yes/no), type of delivery, fetal weight, duration of dilation, duration of expulsion, cause of cesarean.


RESULTS
The records of 4364 women were gathered. The percentages of inductions, nulliparas, oxytocin stimulation, and fetal weight greater than 4 kg and less than 2.5 kg were higher among women taking epidural analgesia. The age of women who received epidurals was significantly lower. The durations of dilation and expulsion were longer among women receiving epidural analgesia, and epidural analgesia was associated with greater risk of instrumental and cesarean deliveries. The significant increase in administration of epidural blocks over the 3-year period of the study was not accompanied by an increased rate of instrumentally assisted deliveries or cesareans.


CONCLUSIONS
It is difficult to evaluate the real influence of epidural analgesia on certain aspects of labor and its evolution. The strength of the association between epidural analgesia and greater risk of increased rates of instrumental and cesarean deliveries may be influenced by factors not considered in the present study.
Fernández-Guisasola
J
J
Unidad de Anestesia-Reanimación, Area de Anestesia, Reanimación y Cuidados Críticos, Fundación Hospital Alcorcón, Madrid. jfguisasola@fhalcorcon.es
Rodríguez Caravaca
G
G
Serrano Rodríguez
Maria L
ML
Delgado González
T
T
García del Valle
S
S
Gómez-Arnau
J I
JI
D000328:Adult; D015360:Analgesia, Epidural / Q000009:adverse effects / Q000706:statistics & numerical data; D016362:Analgesia, Obstetrical / Q000009:adverse effects / Q000706:statistics & numerical data; D000700:Analgesics / Q000494:pharmacology; D002045:Bupivacaine / Q000494:pharmacology; D002585:Cesarean Section / Q000706:statistics & numerical data; D015331:Cohort Studies; D005260:Female; D005283:Fentanyl / Q000494:pharmacology; D006801:Humans; D007743:Labor, Obstetric / Q000187:drug effects; D007744:Obstetric Labor Complications / Q000209:etiology; D009772:Obstetrical Forceps / Q000706:statistics & numerical data; D010121:Oxytocin / Q000627:therapeutic use; D011247:Pregnancy; D012189:Retrospective Studies; D013030:Spain
D000700:Analgesics; D010121:Oxytocin; D005283:Fentanyl; D002045:Bupivacaine