Effects of Ultrasound-Guided SGB Combined with Dexmedetomidine Hydrochloride Nasal Spray on Perioperative Depression, Pain and Inflammatory Factors in Parturients Undergoing Non-Emergent Cesarean Section: A Randomized, Controlled, Double-Blind Trial

INTERVENTION: Intervention group:Intranasal administration of single‐dose dexmedetomidine hydrochloride nasal spray at 0.8 µg/kg;Control group:None; CONDITION: Perioperative stress response of cesarean section, acute postoperative pain, perioperative anxiety, postpartum depression PRIMARY OUTCOME: EPDS scores and PPD positive rate; SECONDARY OUTCOME: Serum stress hormones, inflammatory factors and lactation‐related factors;Athens Insomnia Scale (AIS) scores at 24 hours and 48 hours postoperatively;postoperative recovery;NRS resting and movement pain scores at postoperative 12h, 24h, 48h and 72h; INCLUSION CRITERIA: 1. Elective cesarean delivery (Emergency cesarean delivery is defined as fetal delivery completed within 30 minutes from receipt of obstetric emergency call); 2.Full‐term gestation (gestational age >= 37 weeks); 3.Voluntarily sign the informed consent form to participate in this trial.