Bispectral Index and First-Pass Intubation

This prospective observational study aims to evaluate the association between anesthetic depth, measured by the Bispectral Index (BIS), and first-pass endotracheal intubation success in adult patients undergoing rapid sequence intubation (RSI) in the emergency department. Endotracheal intubation is one of the most critical procedures performed in emergency medicine. Multiple intubation attempts are associated with an increased risk of adverse events, including hypoxemia, aspiration, cardiovascular complications, and death. Although several factors influence first-pass intubation success, the contribution of anesthetic depth at the time of intubation has not been adequately investigated in the emergency department. Patients for whom the treating emergency physician decides to perform RSI will undergo noninvasive BIS monitoring using a disposable forehead sensor. The physician performing the intubation will remain blinded to the BIS value throughout the procedure and will perform intubation according to routine clinical practice. A separate investigator, who is not involved in patient management, will record the BIS value at the time of intubation. The BIS measurements will not be disclosed to the treating team and will not influence clinical decision-making, medication dosing, or patient management. The study is purely observational and does not evaluate the performance or effectiveness of the BIS device itself. The primary objective is to determine whether patients who achieve first-pass intubation success differ in anesthetic depth from those requiring multiple intubation attempts.

Inclusion Criteria: * Adults aged 18 years or older * Patients undergoing rapid sequence intubation (RSI) in the emergency department * No traumatic injury to the frontal region that would interfere with placement of the Bispectral Index (BIS) sensor Exclusion Criteria: * Age younger than 18 years * Pregnant patients * Patients with cardiac arrest or hemodynamic instability at the time of enrollment * Patients intubated without the rapid sequence intubation (RSI) protocol * Refusal to participate in the study (by the patient or, where applicable, a legally authorized representative)