Tubeless anaesthesia for microlaryngeal surgery

An anaesthetic technique for laryngeal microsurgery is described and evaluated using intravenous propofol infusion and topical lignocaine with the patient breathing spontaneously without an endotracheal tube. Eighty adult patients divided into two groups according to their ASA status (Group A; 58 ASA I and II; Group B; 22 ASA III and IV) were analysed. Operating conditions were good in all but one case. Good anaesthesia was achieved in about 70% of patients. The requirement for propofol was less in Group B. Blood pressures decreased significantly following induction (P less than 0.001) but returned towards the preoperative values after ten minutes in Group A patients whereas the recovery was slower in Group B. Apnoea occurred on induction in about 40% of patients overall. PaCO2 showed a similar small increase in both groups. Oxygenation was adequate. The results show that propofol as an infusion in this simple tubeless technique is satisfactory. As the technique was considered potentially hazardous in those patients with upper airway obstruction, such patients were not included in this study.