Comparison of Laryngeal Mask Airway with Tracheal Tube for Ophthalmic Surgery in Paediatric Patients

Abstract

This study of sixty ASA grade 1 or 2 children, aged 1 to 12 years, undergoing elective ophthalmic procedures, compared the use of the laryngeal mask airway (LMA) with that of an endotracheal tube. Changes in intraocular pressure and haemodynamic parameters, and intraoperative and postoperative complications were measured. Patients were randomly allocated into two groups of 30 patients. In group 1, the airway was secured with an LMA and in group 2 with an endotracheal tube. A standard technique of general anaesthesia incorporating positive pressure ventilation was used in both groups. The changes in intraocular pressure, heart rate (HR) and mean arterial pressure (MAP) were observed before and after insertion of the airway device, two minutes after insertion, and pre and post removal of the device. The incidence of airway complications was also noted. There was no significant change in mean intraocular pressure after insertion of the LMA, but removal caused a significant increase to 19.3± 7.6 mmHg (from a baseline of 13.9±4.3 mmHg). In the endotracheal tube group, intubation increased the mean intraocular pressure significantly to 19.9±7.3 mmHg (from a baseline of 13.1±4.0 mmHg) and extubation caused an increase to 24.6±10.4 mmHg which was clinically as well as statistically significant. The incidence of postoperative coughing was lower in the LMA group, but the incidence of vomiting higher. Two patients had displacement of the LMA during the procedure. We conclude that the use of an LMA is associated with less increase in intraocular pressure than the use of an endotracheal tube in children.