Extreme bradycardia during microsurgery of the larynx

Abstract

Introduction: Successful anesthetic management of microlaryngeal cases requires a high degree of cooperation with the surgeon, a reciprocal understanding of the potential problems, and adequate preparation on both sides to meet the anticipated challenges that may arise.
Case description: A 55-year-old male patient (weight 104 kg, height 176 cm), ASA III, was admitted to our hospital for microlaryngeal surgery because of tumor formation of the larynx. The preoperative evaluation revealed no significant personal or family history for adverse reaction to anesthetics. A general anesthesia was scheduled for this patient. Fentanyl 0.3 mg, atropine 0.5 mg, propofol 220 mg and succinylcholine 130 mg were administered for anesthesia induction. After intubation 2.5% sevoflurane was used for anesthesia maintenance. After endotracheal intubation was performed surgeon tried to put on the tube of Kleinsasser. During this procedure the heart rate of the patient extremely dropped from 85 to 25 beats per minute.
Discussion: Performance of conventional and operative direct laryngoscopy, supraglottic tissue distention, and laryngeal stimulation elicit intense cardiovascular responses, resulting in tachycardia, arterial and pulmonary hypertension, and arrhythmias. Although these responses are usually short lived, myocardial ischemia and compromise of cerebral circulation may occur in high-risk patients, resulting in adverse outcomes.
Conclusion: There is a risk of severe bradycardia after putting on the tube of Kleinsasser during microlaryngeal surgery, which can cause hemodynamic