Effect of Lidocaine Ointment Applied on Endotracheal Tube Cuff on Hemodynamic Response in Controlled Hypertensive Patients Undergoing General Anesthesia

Abstract

Background: Laryngoscopy and endotracheal intubation produce transient sympathetic stimulation, resulting in increases in heart rate and blood pressure. These responses may be more clinically relevant in patients with hypertension. Topical application of lidocaine ointment to the endotracheal tube cuff may reduce tracheal stimulation and attenuate these hemodynamic changes. Objective: To evaluate the effect of lidocaine ointment applied to the endotracheal tube cuff on the hemodynamic response in controlled hypertensive patients undergoing general anesthesia. Methods: A cross-sectional study was conducted at District Headquarters Hospital Batkhela, Malakand, over four months after approval of the research synopsis. A total of 81 controlled hypertensive patients aged 30–65 years, classified as ASA physical status II and scheduled for elective surgery under general anesthesia, were selected through consecutive sampling. Approximately 1–2 mL of 2% lidocaine ointment was applied uniformly to the external surface of the endotracheal tube cuff before intubation. Heart rate, systolic blood pressure, diastolic blood pressure, and mean arterial pressure were recorded before induction, immediately after intubation, and at 1, 3, 5, and 10 minutes after intubation. Hemodynamic parameters were also assessed during extubation and at 1, 3, and 5 minutes afterward. Coughing, bucking, straining, laryngospasm, desaturation, and adverse effects were documented. Data were analyzed using SPSS version 26.0, with p <0.05 considered statistically significant. Results: The mean age of participants was 51.2 ± 7.8 years, and 47 (58.0%) were male. The mean duration of hypertension was 5.8 ± 2.9 years. Following intubation, mean heart rate increased from 76.8 ± 7.1 to 91.6 ± 9.2 beats/min, while systolic blood pressure increased from 132.6 ± 7.8 to 153.8 ± 11.6 mmHg immediately after intubation. These parameters gradually returned toward baseline over the subsequent 10 minutes. During extubation, the mean heart rate and systolic blood pressure increased to 88.7 ± 8.8 beats/min and 146.2 ± 10.5 mmHg, respectively. Moderate-to-severe coughing occurred in 18 (22.2%) patients, while bucking or straining occurred in 17 (21.0%). Six patients (7.4%) required pharmacological treatment for intraoperative hemodynamic changes. Only one patient (1.2%) experienced a minor local adverse reaction, and no systemic lidocaine toxicity was observed. Conclusion: In this study, application of lidocaine ointment to the endotracheal tube cuff was associated with transient increases in hemodynamic parameters following intubation and extubation, with values generally returning toward baseline within several minutes. The technique appeared to be well tolerated, with few adverse effects.