General anesthesia tracheal intubation causes sympathetic activation and hemodynamic stress response, which increases perioperative cardiovascular risk, especially in elderly subjects. Tegileridine fumarate is a novel μ-opioid receptor G protein-biased agonist. However, the optimal dose of tegileridine to suppress intubation-induced hemodynamic fluctuations during anesthesia induction remains unclear.

This is an open-label, single-center, age-stratified biased coin up-and-down sequential trial. Subjects undergoing elective surgery requiring tracheal intubation will be divided into young adult group (18-64 years) and elderly group (≥65 years). The primary objective is to determine the ED90 of intravenous tegileridine for inhibiting hemodynamic response to tracheal intubation using centered isotonic regression. Secondary outcomes include induction-related adverse events, serial hemodynamic parameters and sedation scale. This study will provide evidence for rational dosing of tegileridine in clinical anesthesia induction.