Abstracts: Third Meeting of the International Society for Medical Gases (ISMG); Heidelberg, Germany, 29 September-1 October 1999
ABSTRACT NO: 019
Introduction: For 20 years, it has been well known that high concentrations of the inert gas xenon produce general anaesthesia without causing haemodynamic instability. Therefore, we examined the effect of xenon on intraocular pressure (IOP).
Methods: We examined the effect of xenon vs. isoflurane-N2O or isoflurane-air anaesthesia on IOP in 18 pigs weighing 19 ± 1.2 kg. After premedication and induction with thiopental and pancuronium, all the animals were orally intubated and connected to a Physioflex ventilator (Physio BV, Haarlem, The Netherlands). Ventilator settings were fixed throughout the study. No PEEP was used. Analgesia maintenance was achieved by continuous infusion of 0.1 μg kg−1 min−1 remifentanil. Haemodynamic variables, mean arterial (MAP) and central-venous pressure (CVP) as well as end-tidal CO2 (ETCO2) were collected continuously by a monitoring system (Datex, Finland). IOP was measured at the end of each study period by indentation tonometry with a Schiötz tonometer (Winter, Germany). Statistical analysis was performed with a one-way ANOVA for repeated measurements with Bonferroni correlation. After baseline measurements, we studied in a randomized order in all animals the effect of three different anaesthesia regimens on IOP over 2 h. TABLE 1
Results: Measured IOP at baseline corresponded to previous studies . None of the anaesthesia regimens had any effect on the IOP-influencing parameters or on the IOP itself. TABLE 2
Conclusions: Xenon anaesthesia did not increase IOP. Therefore, xenon might be used for anaesthesia in ophthalmic surgery.
1 Jantzen JP. Anaesthesia and intraocular pressure. Anaesthesist
The publication of this supplement has been supported by the sponsors of the Third ISMG Meeting: Abbott, AGA, AstraZeneca, Dräger, Janssen, Medex Medical, Messer Austria, Ohmeda, Pharmacia & Upjohn, Scott Medical Products, Siemens