A premix of 50% nitrous oxide - 50% oxygen for sedation during dental procedures.

The use of a premixed source of 50% N(2)O and 50% O(2) diluted with room air was evaluated in a series of 32 patients undergoing a routine dental procedure. Dependent variables observed were the flow rates of gas necessary to achieve adequate sedation, patient acceptance of the administration method and clinical signs of hypoxia. The median flow rate observed when patients were sedated was 3 liters per minute (range 1 to 5 liters per minute). Twenty-four patients tolerated the dental procedure without need to alter the initial dose, 6 required an increased dose and 2 required less of the gas mixture. No clinical signs of diffusion hypoxia were noted in this small sample. The results of this open clinical evaluation suggest that use of a premixture of 50% N(2)O and 50% O(2) results in adequate sedation, is well tolerated by patients and dose not result in any clinically obvious signs of hypoxia.