The Efficacy and Safety of Pre-operative Bolus Intravenous Lidocaine for Intraoperative Awareness in Cesarean Section: A Randomized Clinical Trial

Abstract

Background: Caesarean section (CS) under general anesthesia (GA) can be associated with an increased risk of intraoperative awareness (IOA). However, the safe pharmacological options are limited in CS. Objectives: This study investigated the effect of preoperative intravenous lidocaine on IOA in CS. Methods: This clinical trial was conducted at Alzahra Teaching Hospital, a referral center in northern Iran affiliated with Guilan University of Medical Sciences (GUMS). From August 2023 to November 2024, eligible women candidates for CS under GA were enrolled in the study and divided into two groups: Lidocaine (n = 26) and placebo (n = 26). In the postpartum stage, a questionnaire containing demographic information and questions about different stages of anesthesia was completed via direct interview. Heart rate (HR) and mean arterial pressure (MAP) were recorded at four time points: before injection of lidocaine (T0), immediately after intubation (T1), at the end of surgery (T2), and after extubation (T3). Results: Of the 52 eligible women, 15.3% experienced IOA. Among the 8 women (15.3%) who experienced IOA, 15 cases of different states of awareness were detected. "Dreaming during surgery and anesthesia" was reported by 53.3%, and "feeling the manipulation of the surgical area" by 26.6% were the most common types of detected awareness states. In terms of MAP and HR changes, a significant difference was recorded only at T1 (P < 0.0001). Conclusions: Preoperative lidocaine could be safely administered in CS with no adverse events and showed positive effects on hemodynamic status. However, at this dosage and timing, it had no significant effect on the incidence of IOA.