Dexmedetomidine for Intermittent Epidural Boluses Versus Continuous Epidural Infusion for Labour Epidural Analgesia

Inclusion Criteria: * Age 18 - 45 years * Scheduled for normal vaginal delivery * ASA physical status ӀI-IӀӀ. * Singleton non-complicated pregnancy. * At least 36 weak of gestation. * Vertex presentation. Exclusion Criteria: * Patient refusal to epidural analgesia. * History of cardiac, liver, or kidney diseases. * History of allergy to amide local anesthetics or study medications. * Any neurological problem. * History of chronic opioid analgesic use. * Any contraindication of regional anesthesia. * Evidence of intrauterine growth restriction or fetal compromise. * Failed or unsatisfactory analgesic block. * Body mass index ≥40 kg/m2