The parameters of mean arterial pressure ( MAP ) , heart rate ( HR ) , pressure of end-tidal carbon dioxide ( P ETCO@ ) , respiratory rate , blood oxygen saturation ( SpO@ ) , observer 's assessment of alertness/sedation ( OAA/S ) and verbal rating score ( VRS ) were recorded at @ min ( baseline ) , @ min ( T@ ) , @ min ( T@ ) , @ min ( T@ ) , @ min ( T@ ) , @ min ( T@ ) and @ min ( T@ ) after the dosing of Dex .