Effect of Dezocine Versus Nalbuphine Combined With Sufentanil on Postoperative Analgesia, Complications, and Free Flap Survival in Patients Undergoing Oral Cancer Radical Surgery: A Randomized Controlled Clinical Trial.

Effect of Dezocine Versus Nalbuphine Combined With Sufentanil on Postoperative Analgesia, Complications, and Free Flap Survival in Patients Undergoing Oral Cancer Radical Surgery: A Randomized Controlled Clinical Trial.

Background: Oral cancer radical surgery often requires free flap reconstruction. Postoperative pain is severe, and traditional opioids like sufentanil have side effects and may adversely affect tumor biology. Dezocine and nalbuphine are opioid agonist-antagonists with potentially better safety profiles. Their comparative effects on analgesia, complications, and flap survival in oral cancer surgery are unknown.

Objective: To compare the efficacy of dezocine versus nalbuphine, both combined with sufentanil, for postoperative analgesia, and to evaluate their impact on postoperative complications and free flap survival/function in patients undergoing oral cancer radical surgery with flap reconstruction.

Methods: This is a prospective, randomized, double-blind, controlled trial. Sixty eligible patients (aged 18-70, ASA I-III) will be randomly assigned (1:1) to receive postoperative patient-controlled intravenous analgesia (PCIA) with either Sufentanil + Dezocine or Sufentanil + Nalbuphine. The primary outcome is pain intensity assessed by the Visual Analogue Scale (VAS) at 2, 24, and 48 hours postoperatively. Secondary outcomes include flap survival status, sensory function recovery, incidence of adverse events (e.g., nausea, vomiting), and hospitalization duration.

Potential Impact: This study may identify a superior postoperative analgesic regimen that provides effective pain relief while potentially improving flap outcomes and minimizing side effects for oral cancer patients.

Design: Single-center, prospective, randomized, double-blind, active-controlled, parallel-group trial.

Interventions:

Group D: Sufentanil (1.0 µg/kg) + Dezocine (0.4 mg/kg) diluted to 150ml with normal saline for PCIA (no basal infusion, bolus 2.5 ml, lockout 15 min).

Group N: Sufentanil (1.0 µg/kg) + Nalbuphine (1.0 mg/kg) diluted to 150ml with normal saline for PCIA (parameters identical to Group D).

Standardized general anesthesia protocol for both groups.

Primary Outcome: Postoperative pain scores (VAS, 0-10) at rest at 2, 24, and 48 hours after surgery.

Secondary Outcomes:

Flap survival status (e.g., hematoma, dehiscence, necrosis, infection) on postoperative days 1-7.

Flap sensory function: static/dynamic two-point discrimination and Semmes-Weinstein monofilament test on days 1-7.

Incidence of postoperative adverse events (nausea, vomiting, pruritus, dizziness, sedation).

Postoperative hospital stay duration.

Ramsay sedation scores at 2, 24, and 48 hours.

Intraoperative hemodynamics and blood loss.

Sample Size: 60 patients (30 per group). The calculation is based on a pilot study detecting a difference in 24h VAS scores (1.52 vs 2.35, SD=0.89) with 90% power and α=0.05, accounting for a 20% dropout rate.

Inclusion Criteria:

1. Diagnosed with oral malignant tumor.
2. Scheduled for oral cancer radical surgery with free flap reconstruction at Sun Yat-sen Memorial Hospital.
3. Age between 18 and 70 years.
4. Sign informed consent.

Exclusion Criteria:

1. Use of analgesic medications within two weeks prior to surgery.
2. History of diabetes, arteriosclerosis, or peripheral vascular disease.
3. Use of hormones, chemotherapy, or immunosuppressants.
4. Severe cardiac, pulmonary, hematological, hepatic, or renal diseases.
5. Known allergy to the study drugs.