Pethidine Versus Nitrous Oxide for Pain Relief During Labor
Pethidine Versus Nitrous Oxide for Pain Relief During Labor
Systematic opioids and inhaled nitrous oxide (N2O ) are common methods for pain relief during
 labor. The aim of the current study is to evaluate the efficacy of systemic pethidine
 compared to N2O given for pain relieve in term, multiparous women in labor.
Pain relief during labor and delivery is an essential part of good obstetrical care. Labor
 pain and its relief have implications on the course of labor, maternal and fetal outcomes and
 the satisfaction with childbirth overall. Many women would like to have a choice in pain
 relief during labor but also would like to avoid invasive methods of pain management in labor
 (as epidural). Both, inhaled analgesia and parenteral opioids are common pharmacological
 interventions aim to relieve the pain of labor.Nitrous oxide in a 50/50 mix with oxygen is
 the most common concentration used for labor pain management. It is self-administered via
 facemask, intermittently, and has rapid onset and offset effect. Main side effects, including
 nausea, vomiting, dizziness and drowsiness. Pethidine is one of the most frequently used
 opiate agonists. It can be given intravenous or intramuscularly. Its analgesic effect starts
 within 10-20 minutes and lasts 2-4 hours. Reported maternal side effects include nausea,
 vomiting and dysphoria. Pethidine may lead to changes in fetal heart rate tracing during
 labor, respiratory depression, impaired sucking reflex and restlessness.

 Given the fact that these two routine interventions are given in different ways and have
 different side effects profile, the investigators aim in this randomized controlled trial to
 compare the analgesic effect of these two methods and their maternal and perinatal secondary
 effects in multiparous laboring women.
Inclusion Criteria:

 1. Multiparity (para 2 or more).

 2. Term pregnancy: 37-42 weeks of gestation.

 3. Singleton pregnancy.

 4. Vertex presentation.

 5. In labor: at least 2 contraction in ten minutes and cervical dilatation of 2
 centimeters or more.

 Exclusion Criteria:

 1. Women who desire epidural as a first line analgesia during labor.

 2. Women receiving pethidine during the last 24 hours (prior to entering labor room).

 3. Contra-indication for vaginal delivery.

 4. Contra-indication or allergic reaction to either pethidine or nitrous oxide.

 5. History of drug abuse.

 6. Previous cesarean delivery.