Dexmedetomidine-esketamine Combination and Moderate-to-severe Pain After Spinal Surgery

Phase 4Not Yet RecruitingNCT07523321

Peking University First Hospital274 enrolled

Overview

Spinal surgery is generally followed by severe postoperative pain, and poor pain control may cause adverse outcomes such as cardiovascular events, neurocognitive disorders, and chronic postsurgical pain (CPSP). In previous studies, perioperative use of dexmedetomidine or esketamine is each associated with improved analgesia after surgery. Recent studies suggest that combined use of dexmedetomidine and esketamine may produce synergetic effects in improving analgesia. This trial is designed to test the hypothesis that perioperative combined use of dexmedetomidine and esketamine may improve analgesia and reduce moderate-to-severe pain in patients after spinal surgery.

Spinal surgery is genrally followed by severe pain due to extensive trauma. The reported rate of moderate-to-severe pain ranged from 30% to 63%. Uncontrolled postoperative pain is associated with worse outcomes including cardiovascular events, neurocognitive complications, and chronic postsurgical pain. Opioids are the main stay of analgesia after spinal surgery. However, high dose opioids provoke side effects such as nausea and vomiting, delirium, and even respiratory depression. Multimodel analgesia is suggested for these patients. Dexmedetomidine is a highly selective alpha 2 adrenergic receptor agonist with sedative, analgesic, and anxiolytic effects. A meta-analysis suggest that, for patients undergoing spinal surgery, intraoperative dexmedetomidine improved early postoperative analgesia, but the effect did not persist beyond 6 hours. Ketamine is a noncompetitive N-Methyl-D-aspartic acid (NMDA) receptor antagonist and has been used as an anesthetic and analgesic for decades. Esketamine is the S-enantiomer of ketamine and has an analgesic potent of approximately 2 times of that of ketamine. Small sample size studies in patients undergoing spinal surgery showed that intra- or postoperative use of subanesthetic dose esketamine improved analgesia and reduced rescue analgesics. The analgesic effects of dexmedetomidine and esketamine are dose-dependent. However, routine dose dexmedetomidine may increase bradycardia and hypotension, and even subanethetic dose esketamine may produce neuropsychiatric symptoms. Combined use of dexmedetomdine and esketamine may augment analgesic and sedative effects while decreasing side effects. In a previous study, using low-dose dexmedetomidine (1 ug/ml) and esketamine (0.25 mg/ml) as supplements to self-controlled sufentanil analgesia improved pain relief and sleep quality after spinal surgery, but the rate of moderate-to-severe pain remained high. In a recent study, when used as a supplement to sufentanil analgesia, increasing esketamine dose to 0.5 mg/ml did not significantly improve analgesia, whereas increasing esketamine dose to 0.75 mg/ml increased nausea and vomiting. In available studies, use of dexmedetomidine and/or esketamine were mostly limited to either intra- or postoperative period. Introperative use of the combination only improve early postoperative analgesia. Whereas postoperative use of the combination did not have effects on peak intraoperative stress. It is reasonable to hypothesize that using dexmedetomidine-esketamine combination during both the intra- and postoperative periods may provide better analgesia in patients after spinal surgery.

Interventions

Combined dexmedetomidine-esketamine administrationDRUG

During anesthesia, a loading dose (0.2 ml/kg) of dexmedetomidine-esketamine (DEX-ESK) combination (DEX 2 ug/ml; ESK 1 mg/ml) will be infused after anesthesia induction (DEX 0.4 ug/kg; ESK 0.2 mg/kg), followed by a continuous infusion at 0.1 ml/kg/h (DEX 0.2 ug/kg/h; ESK 0.1 mg/kg/h) until 1 hour before the expected end of surgery. After surgery, patient-controlled intravenous analgesia will be established with dexmedetomidine (DEX 1.5 ug/ml), esketamine (ESK 0.5 mg/ml), and sufentanil (1.25 ug/ml), programmed to deliver 2-ml boluses (DEX 3.0 ug, ESK 1 mg, and sufentanil 2.5 ug) with a 8-10-minute lockout interval and a 1-ml/h (DEX 1.5 ug/h, ESK 0.5 mg/h, and sufentanil 1.25 ug/h) background infusion, and used for up to 48 hours.

Placebo administrationDRUG

During anesthesia, a loading dose (0.2 ml/kg) of normal saline will be infused after anesthesia induction, followed by a continuous infusion at 0.1 ml/kg/h until 1 hour before the expected end of surgery. After surgery, patient-controlled intravenous analgesia will be established with sufentanil (1.25 ug/ml), programmed to deliver 2-ml boluses (sufentanil 2.5 ug) with a 8-10-minute lockout interval and a 1-ml/h (sufentanil 1.25 ug/h) background infusion, and used for up to 48 hours.

Eligibility

Sex: ALLMin age: 40 YearsMax age: 80 Years

Medical Language ↔ Plain English

Inclusion Criteria: 1. Aged \>= 40 years but \< 80 years; 2. Scheduled to undergo elective posterior cervical, thoracic, or lumbar spine surgery with an expected duration \>= 2 hours under general anesthesia; 3. Required patient-controlled intravenous analgesia (PCIA) after surgery. Exclusion Criteria: 1. Uncontrolled preoperative hypertension (ward systolic blood pressure \> 180 mmHg or diastolic blood pressure \> 110 mmHg); 2. Severe bradycardia (heart rate \<= 50 bpm), sick sinus syndrome, atrioventricular block of grade II or higher without pacemaker implantation, a history of myocardial infarction within one year, or presence of rapid ventricular arrhythmia; 3. History of schizophrenia, epilepsy, Parkinson's disease, or myasthenia gravis, or prresence of intracranial hypertension; 4. Uncontrolled hyperthyroidism or pheochromocytoma; 5. Inability to communicate due to coma, severe dementia, or language barrier; 6. Severe cardiac insufficiency (preoperative left ventricular ejection fraction \< 30% or New York Heart Association Functional classification IV), severe hepatic dysfunction (Child-Pugh class C), severe renal dysfunction (preoperative dialysis), or American Society of Anesthesiologists physical status \>= IV; 7. Other conditions that are considered unsuitable for study participation.

Outcomes

Primary Outcomes

Incidence of moderate-to-severe pain within 72 hours after surgery

Pain intensity will be assessed at 1 and 6 hours, and then twice daily (8:00-10:00, 18:00-20:00) until 72 hours after surgery, using the Numerical Rating Scale (NRS; an 11-point scale where 0=no pain and 10=the worst pain) both at rest and with movement (e.g., bed turning, walking). NRS pain scores 1-3 points indicate mild pain, 4-6 points indicate moderate pain, and 7-10 points indicate severe pain.

Time frame: Up to 72 hours after surgery

Secondary Outcomes

Incidence of delayed neurocognitive recovery at postoperative day 5

Cognitive function will be assessed with the Montreal Cognitive Assessment (MoCA; scores range from 0 to 30, with higher scores indicating better function) at baseline and on the 5th day or before hospital discharge after surgery. Delayed neurocognitive recovery is defined as a decline of MoCA score of \>= 1 stndard deviation (SD) from baseline.

Time frame: Up to 5 days after surgery

Incidence of cardiovascular events within 30 days after surgery

Cardiovascular events include myocardial injury after non-cardiac surgery (MINS; including myocardial infarction), non-fatal cardiac arrest, stroke, and all-cause mortality. The diagnosis of MINS will strictly follow the consensus of the American Heart Association (AHA).

Time frame: Up to 30 days after surgery