Preoperative Anxiety's Impact on the Median Effective Dose of Esketamine for Alleviating Propofol Injection Pain in Patients Undergoing Painless abortion: A Randomized, Double-Blind, Controlled Trial.

Background: Propofol injection pain (PIP) is a frequent adverse effect during anesthesia induction, impacting patient comfort and satisfaction. Esketamine has been shown to alleviate PIP, but the optimal dose, especially in relation to preoperative anxiety levels, remains unclear. Preoperative anxiety may heighten pain perception and influence analgesic requirements. Methods: A randomized, double-blind, controlled trial was conducted at The Affiliated Women and Children's Hospital of Ningbo University. A total of 150 eligible patients scheduled for painless abortion were assessed using the Spielberger State Anxiety Inventory - State form (STAI-S) and categorized into non-anxious (STAI-S score <40) and anxious (STAI-S score ≥40) groups. Patients were randomized using a computer-generated random number table to receive one of five escalating doses of esketamine (0.10, 0.12, 0.14, 0.17, or 0.20 mg/kg) prior to propofol administration. The primary outcome was the occurrence of PIP, assessed using Ambesh's four-point pain scale. Secondary outcomes included hemodynamic parameters and adverse events such as hypotension, bradycardia, and hypoxemia. Results: A clear dose-response relationship was observed, with higher doses of esketamine significantly reducing the incidence of PIP in both groups. Anxious patients required higher doses of esketamine to achieve comparable pain relief to non-anxious patients. The effective dose for 50% of patients (ED Conclusion: Preoperative anxiety significantly increases the ED