Intravenous versus topical lidocaine gel administered at intubation for prevention of peri-extubation airway complications in adults undergoing orthopaedic surgery: protocol for a randomised controlled trial.

Abstract

Peri-extubation airway complications such as coughing, laryngospasm and oxygen desaturation remain common during emergence from general anaesthesia and may contribute to postoperative morbidity. Lidocaine is widely used to reduce airway reactivity during extubation; however, evidence comparing intravenous and topical administration routes in adults remains limited. In particular, little evidence exists regarding topical lidocaine gel applied at the time of endotracheal intubation. This trial aims to compare intravenous lidocaine with topical lidocaine gel for prevention of peri-extubation airway complications in adults undergoing elective orthopaedic surgery. This is a prospective, single-centre, randomised, observer-blinded, parallel-group controlled trial. A total of 120 adult patients undergoing elective orthopaedic surgery under general anaesthesia with endotracheal intubation will be randomly allocated in a 1:1 ratio to receive either intravenous lidocaine 1.5 mg/kg before intubation or topical 2% lidocaine gel applied to the endotracheal tube before intubation. The primary outcome is a composite of severe cough, laryngospasm or oxygen desaturation within 10 min after extubation. Secondary outcomes include assessment of individual airway complications, postoperative sore throat, dysphonia, haemodynamic responses and recovery characteristics in the postanaesthesia care unit. Data will be analysed according to the intention-to-treat principle. Ethical approval has been obtained from the Ethics Committee of Tehran University of Medical Sciences (approval number: IR.TUMS.SPH.REC.1404.293) and the Institutional Review Board of Al-Hussein Teaching Hospital, Iraq. Written informed consent will be obtained from all participants before enrolment. The results of the study will be disseminated through peer-reviewed journal publication and presentation at national and international scientific conferences. IRCT20260209068811N1.