Different Doses of Dexmedetomidine Combined With Esketamine in Women Undergoing Cesarean Delivery

Different Doses of Dexmedetomidine Combined With Esketamine for Analgesia in Women Undergoing Cesarean Delivery: a Pilot Randomized Trial

Esketamine is a commonly used analgesic during cesarean delivery, but may produce transient neuropsychiatric symptoms. Dexmedetomidine has both sedative and analgesic effects. When used in combination with esketamine, dexmedetomidine can reduce esketamine related neuropsychiatric effects after general anesthesia. The investigator speculate that combining low-dose dexmedetomidine with esketamine may also reduce neuropsychiatric adverse effects of esketamine in women undergoing cesarean section. This pilot trial is designed to determine the minimum dose of dexmedetomidine that can effectively prevent neuropsychiatric side effects of antidepressive dose esketamine (0.2mg/kg) in women undergoing cesarean delivery.

Esketamine is a commonly used anesthetic and analgesic drug during the perioperative period. Recent studies found that low-dose esketamine has rapid onset antidepressant effects and reduces postpartum depression when administered during cesarean delivery. However, even low-dose esketamine produces transient neuropsychiatric symptoms.

Dexmedetomidine is a high selective alpha2-adrenoceptor agonist and has both sedative and analgesic effects. When used in combination with esketamine, dexmedetomidine reduces esketamine related neuropsychiatric adverse reactions in patients undergoing general anesthesia.

The investigator speculate that combining low-dose dexmedetomidine with esketamine may also reduce neuropsychiatric adverse effects of esketamine in women undergoing cesarean delivery. The purpose of this pilot trial is to determine the minimum dose of dexmedetomidine that can effectively prevent neuropsychiatric side effects of antidepressve dose esketamine (0.2mg/kg) in women undergoing cesarean delivery.

Inclusion criteria:

• Pregnant women aged ≥18 years.
• Scheduled for elective or emergency cesarean delivery under neuraxial anesthesia.

Exclusion criteria:

• A previous history of schizophrenia;
• Severe complications of pregnancy, such as pre-eclampsia, placenta accreta spectrum, or HELLP (intravascular haemolysis, elevated liver enzymes, and low platelet count) syndrome; or American Society of Anesthesiologists classification III or higher;
• Any contraindications to ketamine or esketamine, such as refractory hypertension, severe cardiovascular disease, or hyperthyroidism;
• Any contraindications to dexmedetomidine, such as sick sinus syndrome, severe sinus bradycardia (<50 beats per minute), or second-degree or above atrioventricular block without pacemaker;
• Other conditions that are considered unsuitable for study participation.